Light emitting device and electronic equipment using the same

In the present invention, a light emitting device formed on a substrate, for example, an organic light emitting device (OLED: Organic Li) ght Emitting Device) is related to an OLED panel in which a ght Emitting Device) is enclosed between the substrate and a cover material. In addition, in an OLED module in which an IC including a controller is mounted on the OLED panel. Related. In this specification, the OLED panel and the OLED module are collectively referred to as a light emitting device. Refer to. The present invention further relates to an electronic device using the light emitting device.

Since OLED emits light by itself, it has high visibility and is a buckler required for liquid crystal displays (LCDs). It does not require a light and is ideal for thinning, and there is no limit to the viewing angle. Therefore, in recent years OLE Light emitting devices using D are attracting attention as display devices that replace CRTs and LCDs.

OLED has luminescence (Electroluminescence) generated by applying an electric field. A layer containing the obtained organic compound (organic light emitting material) (hereinafter referred to as an organic light emitting layer) and an anode layer. , With a cathode layer. Luminescence in organic compounds starts from the singlet excited state. Emission (fluorescence) when returning to the ground state and emission (phosphorescence) when returning from the triplet excited state to the ground state ), But the light emitting device of the present invention uses one of the above-mentioned light emission. Or both luminescences may be used.

In this specification, all the layers provided between the anode and the cathode of the OLED are referred to as an organic light emitting layer. Define. Specifically, the organic light emitting layer includes a light emitting layer, a hole injection layer, an electron injection layer, a hole transport layer, and electricity. Child transport layer and the like are included. Basically, OLED has a structure in which an anode / light emitting layer / cathode are laminated in this order. In addition to this structure, anode / hole injection layer / light emitting layer / cathode and anode / hole injection It may have a structure in which layers, light emitting layers, electron transport layers, cathodes, etc. are laminated in this order.

<p num="0005"> The problem in putting a light emitting device into practical use is OLE due to deterioration of organic light emitting materials. It was a decrease in the brightness of D.</p><p num="0006"> Organic luminescent materials are vulnerable to moisture, oxygen, light and heat, which accelerate their deterioration. Specifically, the structure of the device that drives the light emitting device, the characteristics of the organic light emitting material, the electrode material, and the production. The rate of deterioration depends on the conditions in the manufacturing process, the driving method of the light emitting device, and the like.</p><p num="0007"> Even if the voltage applied to the organic light emitting layer is constant, if the organic light emitting layer deteriorates, the brightness of the OLED will change. It is degraded and the displayed image becomes unclear. In the present specification, organic light emission is emitted from a pair of electrodes. The voltage applied to the layer is defined as the OLED drive voltage (Vel).</p><p num="0008"> In addition, a colorization table using three types of OLEDs corresponding to R (red), G (green), and B (blue). In the method shown, the organic light emitting material constituting the organic light emitting layer depends on the corresponding color of the OLED. different. As a result, the organic light emitting layer of the OLED deteriorates at a different rate for each corresponding color. Sometimes. In this case, over time, the brightness of the OLED will vary from color to color. It becomes impossible to display an image having a desired color on the light emitting device.</p><p num="0009"> In view of the above, the present invention reduces the brightness of the OLED even if the organic light emitting layer deteriorates. It is an object of the present invention to provide a light emitting device capable of performing a clear and desired color display. To.</p>

<p num="0010"> The present inventor keeps the OLED drive voltage constant to emit light and the current flowing through the OLED. In the latter case, the decrease in OLED brightness due to deterioration is smaller than when the light is emitted while keeping the value constant. I paid attention to the last thing. In this specification, the current flowing through the OLED is referred to as the OLED drive current. Called (Iel).</p><p num="0011"> Figure 2 shows when the OLED drive voltage is constant and when the OLED drive current is constant. , Shows the change in OLED brightness. As shown in Fig. 2, it is better to keep the OLED drive current constant. , The decrease in brightness due to deterioration is small.</p><p num="0012"> Therefore, the present inventor has an OLED drive voltage even if the OLED drive current decreases due to deterioration or the like. We devised a light emitting device that can always keep the OLED drive current constant by correcting the above.</p><p num="0013"> Specifically, the light emitting device of the present invention has a first means for measuring an OLED drive current and an OLED drive. A second means of calculating the ideal value (reference value) of the dynamic current from the video signal, and the measured value By correcting the OLED drive voltage with the third means of comparing the reference values, the measured values and the reference values It has a fourth means of reducing the difference in values.</p><p num="0014"> With the above configuration, the light emitting device of the present invention keeps the OLED current constant even if the organic light emitting layer deteriorates. Therefore, it is possible to suppress the decrease in brightness, and as a result, a clear image is displayed. Can be</p><p num="0015"> And colorization using three types of OLED corresponding to R (red), G (green), B (blue) In the case of the display method, the OLED drive current is measured for each OLED of each color, and the OLED drive voltage is calculated. You may try to correct it. With this configuration, the organic light emitting layer of the OLED becomes the corresponding color. Even if it deteriorates at a different speed, it prevents the brightness of each color from being out of balance and displays the desired color. Can be shown.</p><p num="0016"> The temperature of the organic light emitting layer depends on the outside air temperature and the heat generated by the OLED panel itself. In general, the value of the current flowing through OLED changes depending on the temperature. Figure 3 shows the temperature of the organic light emitting layer. The change in the voltage-current characteristics of the OLED when the degree is changed is shown. Organic when the voltage is constant As the temperature of the light emitting layer increases, the OLED drive current increases. And with the OLED drive current Since the brightness of OLED is proportional, the larger the OLED drive current, the more OL The brightness of the ED increases. In Fig. 2, the brightness at constant voltage goes up and down in a cycle of about 24 hours. This is because the temperature difference between day and night is reflected. However, with the light emitting device of the present invention Is an OLED drive voltage that corrects the OLED drive voltage even if the temperature of the organic light emitting layer changes. The flow can be kept constant at all times. Therefore, a constant brightness can be obtained regardless of temperature changes. In addition, it is possible to prevent the power consumption from increasing as the temperature rises.</p><p num="0017"> In addition, in general, depending on the type of organic luminescent material, the OLED drive current in temperature changes Since the degree of change is different, the brightness of the OLED of each color changes depending on the temperature in the color display. It can change into a rapala. However, the light emitting device of the present invention is affected by temperature changes. Since it is possible to obtain a constant brightness without having to do so, it is possible to prevent the brightness of each color from being out of balance. It can display the desired color.</p><p num="0018"> Further, in the light emitting device of the present invention, when measuring the OLED current, a table is displayed contrary to the intention of the user. It is very convenient because it is not necessary to change the displayed screen.</p><p num="0019"> Also, in a general light emitting device, the wiring itself that supplies current to each pixel has resistance, so wiring The potential drops slightly depending on the length of. And this drop in potential depends on the image to be displayed. But it's very different. In particular, in multiple pixels to which current is supplied from the same wiring, the number of gradations As the proportion of high pixels increases, the current flowing through the wiring increases, and the potential drops significantly. Is done. As the potential drops, the voltage applied to the OLED of each pixel decreases, so each The current supplied to the pixel becomes smaller. Therefore, a constant gradation is displayed in a predetermined pixel. Even if you try, if the number of gradations of other pixels to which current is supplied from the same wiring changes, Along with this, the current supplied to the predetermined pixel changes, and as a result, the number of gradations also changes. However In the light emitting device of the present invention, the measured value and the reference value are obtained for each displayed image, and the OLED current is corrected. Therefore, even if the displayed image changes, the desired number of gradations can be displayed by correction. Can be done.</p>

<p num="0020"> According to the above configuration, the present invention suppresses a decrease in the brightness of the OLED even if the organic light emitting layer deteriorates. As a result, a clear image can be displayed. In addition, OLE corresponding to each color In the case of a color display light emitting device using D, the organic light emitting layer of the OLED is for each corresponding color. Even if it deteriorates at different speeds, it prevents the brightness of each color from being out of balance and displays the desired color. be able to.</p><p num="0021"> In addition, the temperature of the organic light emitting layer may be affected by the outside air temperature or the heat generated by the OLED panel itself. , It is possible to suppress the change in the brightness of the OLED, and the power consumption increases as the temperature rises. It can be prevented from growing. Also, in the case of a color display light emitting device, it depends on the temperature change. Since it is possible to suppress the change in the brightness of the OLED of each color without doing so, the brightness of each color is balanced. Can be prevented from collapsing and a desired color can be displayed.</p><p num="0022"> The correction circuit shown in the present specification is a digital amount in each circuit of the correction circuit. The processing may be performed using either the analog amount or the analog amount. And A / D conversion circuit and D / The designer can arbitrarily decide which circuit to install the A conversion circuit after.</p>

<figref num="1">The block diagram of the light emitting device of this invention.</figref><figref num="2">Changes in brightness due to deterioration during constant current drive or constant voltage drive.</figref><figref num="3">Changes in current due to the temperature of the organic light emitting layer.</figref><figref num="4">The pixel circuit diagram of the light emitting device of this invention.</figref><figref num="5">Block diagram of the correction circuit.</figref><figref num="6">Block diagram of the correction circuit.</figref><figref num="7">Relationship diagram of deviation current and correction voltage.</figref><figref num="8">Block diagram of the correction circuit.</figref><figref num="9">The figure which shows the driving method of the light emitting device of this invention.</figref><figref num="10">The pixel circuit diagram of the light emitting device of this invention.</figref><figref num="11">The figure which shows the driving method of the light emitting device of this invention.</figref><figref num="12">Block diagram of pixel counter circuit.</figref><figref num="13">The figure which shows the operation of the memory for a pulse counter.</figref><figref num="14">Block diagram of the correction circuit.</figref><figref num="15">Block diagram of voltage value calculation circuit.</figref><figref num="16">Block diagram of the drive circuit.</figref><figref num="17">The external view of the light emitting device of this invention.</figref><figref num="18">The external view of the light emitting device of this invention.</figref><figref num="19">Change in voltage due to correction.</figref><figref num="20">The figure which shows the manufacturing method of the light emitting device of this invention.</figref><figref num="21">The figure which shows the manufacturing method of the light emitting device of this invention.</figref><figref num="22">The figure which shows the manufacturing method of the light emitting device of this invention.</figref><figref num="23">The figure which shows the manufacturing method of the light emitting device of this invention.</figref><figref num="24">The figure of the electronic device using the light emitting device of this invention.</figref>

Hereinafter, the configuration of the present invention will be described.

FIG. 1 shows the configuration of the OLED panel of the present invention in a block diagram. 101 is the pixel part, A plurality of pixels 102 are formed in a matrix. 103 is the source line drive circuit, 1 04 is a gate line drive circuit.

In FIG. 1, the source line drive circuit 103 and the gate line drive circuit 104 are combined with the pixel unit 101. Although formed on the same substrate, the present invention is not limited to this configuration. With source line drive circuit The 103 and the gate line drive circuit 104 are formed on a substrate different from the pixel portion 101, and the FPC or the like is formed. It may be connected to the pixel unit 101 via the connector of. Also, in Figure 1, the source line The drive circuit 103 and the gate line drive circuit 104 are provided one by one, and the present invention has this structure. Not limited to Naru. The number of source line drive circuits 103 and gate line drive circuits 104 is left to the designer. It can be set at will.

Further, in FIG. 1, the source lines S1 to Sx, the power supply lines V1 to Vx, and the gate line G1 are connected to the pixel portion 101. ~ Gy is provided. The number of source lines and power lines is not always the same. .. In addition to these wirings, another different wiring may be provided.

An OLED 105 is provided for each pixel 102. OLED105 has anode and cathode In this specification, when the anode is used as a pixel electrode (first electrode), the cathode is opposed to each other. It is called an electrode (second electrode), and when the cathode is used as a pixel electrode, the anode is called a counter electrode.

The pixel electrodes of the OLED 105 of each pixel 102 are power lines via one or more TFTs. It is connected to any one of V1 to Vx. And all power lines V1 ~ Vx are ammeter 10 It is connected to the variable power supply 106 via 7. In addition, the counter electrode of OLED105 is all Is connected to the variable power supply 106. Note that the OLED105 has one or more counter electrodes. It may be connected to the variable power supply 106 via the element of.

In the present specification, the variable power supply is a power supply that supplies current or voltage to a circuit or an element. Moreover, it means a power source in which the supplied voltage or current is variable. In Figure 1, the variable power supply 10 6 is kept at a high potential (Vdd) on the power line side and a low potential (Vss) on the counter electrode side. Is connected to the sea urchin. However, the present invention is not limited to this configuration, and the variable power supply 106 is an OLED. It suffices if the current flowing through 105 is connected so as to have a forward bias.

In Fig. 1, all power lines V1 to Vx are connected in series with the ammeter 107. Some of the source lines V1 to Vx are connected to the variable power supply 106 via an ammeter 107, and the remaining power The source line may be connected to the variable power supply 106 without going through the ammeter 107.

The position where the ammeter 107 is provided must be between the variable power supply 106 and the power supply line. It may be between the variable power supply 106 and the counter electrode. The ammeter used in the present invention is wiring. Any configuration may be used as long as it can detect changes in the current value flowing through the circuit. I.

And 108 is a correction circuit, and the value of the current measured by the ammeter 107 (measured value). Controls the voltage supplied from the variable power supply 106 to the counter electrode and power supply lines V1 to Vx based on To do. A video signal is input to the correction circuit 108, and the video signal is ideal. Calculate the reference value, which is the value of the current.

The ammeter 107, the variable power supply 106, and the correction circuit 108 each have a pixel portion 101 formed therein. It is formed on a board different from the board on which it is mounted, and is connected to the pixel unit 101 via a connector or the like. It may be formed on the same substrate as the pixel portion 101 if it can be manufactured.

In the case of the colorized display method, a variable power supply and ammeter are provided for each color, and the OLED for each color is equipped. Then, the OLED drive voltage may be corrected. At this time, the correction circuit is for each color. It may be provided, or a correction circuit common to OLEDs of a plurality of colors may be provided.

Figure 4 shows the detailed configuration of each pixel. The pixels shown in FIG. 4 are source lines Si (i = 1 to x). , Gate line Gj (j = 1 ~ y), Power line Vi, Switching TFT110, Drive TF It has a T111, a capacitor 112 and an OLED105. Note that the pixels shown in Fig. 4 The configuration is just an example, and the number, types, and connections of wiring and elements that a pixel has are shown in Fig. 4. It is not limited to the configuration. The light emitting device of the present invention uses a variable power supply 106 to generate an OLED for each pixel. Any configuration may be used as long as the OLED drive voltage of the above can be controlled.

In Fig. 4, the gate electrode of the switching TFT110 is connected to the gate wire Gj. .. And the source area and drain area of the switching TFT110 are the source line S on one side. The other is connected to i and the other is connected to the gate electrode of the driving TFT111. And drive T The source area and drain area of the FT111 are one for the power supply line Vi and the other for the OLED1. It is connected to the pixel electrode of 05. The capacitor 112 is the gate electrode of the driving TFT 111. It is formed between the power line Vi and the power line Vi.

In the pixel shown in FIG. 4, the potential of the gate line Gj is controlled by the gate line drive circuit 104. A video signal is input to the source line Si by the source line drive circuit 103. Switch When the ching TFT110 is turned on, the video signal input to the source line Si will switch. It is input to the gate electrode of the driving TFT 111 via the ching TFT 110. And drive When the dynamic TFT111 is turned on by the video signal, the variable power supply 106 makes the OLED10 Since the OLED drive voltage is applied between the pixel electrode and the counter electrode of 5, OLED105 Lights up.

The ammeter 107 has a first means of measuring the OLED current flowing through all the pixels. .. When the OLED 105 is emitting light, the current is measured by the ammeter 107. Current The period for measuring is different depending on the performance of the ammeter 107, and it should be longer than the measurable length. And are needed. In the ammeter 107, the average value or the maximum value of the current flowing during the measurement period Make sure that the high value is read.

The current flowing through the ammeter includes leakage current due to the off current of the transistor, etc. There is a possibility. Therefore, a video signal that does not allow current to flow through the OLED of all pixels. Is input, and the current value flowing through the ammeter at that time is measured. And actually measure the current At that time, subtract the memorized current value. Then, instead of leakage current etc. An accurate current value can be obtained by removing the represented noise component.

The measured value obtained by the ammeter 107 is sent to the correction circuit 108 as data. one On the other hand, a video signal is input to the correction circuit 108. Figure 5 shows the configuration of the correction circuit 108. Shown in the figure.

120 is a current value calculation circuit, 121 is a current value comparison circuit, and 122 is a power supply control circuit. Den The flow value calculation circuit 120 is an ideal current flowing from the input video signal to the ammeter 107. It has a second means of calculating a value (reference value) from a video signal.

The current value comparison circuit 121 has a third means for comparing the measured value with the reference value.

Then, in the power supply control circuit 122, when there is a certain difference between the measured value and the reference value. In addition, the OLED drive voltage is corrected by controlling the variable power supply 106, and the difference between the measured value and the reference value is calculated. It has a fourth means of shrinking. Specifically, the voltage between the power supply lines V1 to Vx and the counter electrode By correcting, the OLED drive voltage in the OLED 105 of each pixel 102 Is corrected and an OLED drive current of the desired magnitude flows.

The OLED drive voltage may be corrected by controlling the potential on the power supply line side. However, it may be corrected by controlling the potential on the counter electrode side. Also, the potential on the power line side It may be corrected by controlling both the potential on the counter electrode side and the potential on the counter electrode side.

In addition, the gate voltage of the driving TFT111 cannot be secured due to the voltage correction. It is desirable to adjust the potential of the video signal in advance so that

FIG. 19 shows the OL of each color when controlling the potential on the power supply line side in the color light emitting device.The change of OLED drive voltage of ED is shown. In FIG. 19, Vr is a supplement in OLED for R. The front OLED drive voltage, Vr₀Is the corrected OLED drive voltage. Similarly, V g is the OLED drive voltage before correction in the OLED for G, and Vg₀Is the corrected OLED It is a drive voltage. Vb is the OLED drive voltage before correction in OLED for B, Vb₀Is the corrected OLED drive voltage.

In the case of FIG. 19, the potential of the counter electrode (opposite potential) is fixed at the same height in all OLEDs. Has been done. Measure the OLED drive current for each OLED of each color, and the potential of the power supply line (power supply potential) ) Is controlled by a variable power supply to correct the OLED drive voltage.

According to the above configuration, the present invention suppresses a decrease in the brightness of the OLED even if the organic light emitting layer deteriorates. As a result, a clear image can be displayed. In addition, OLE corresponding to each color In the case of a color display light emitting device using D, the organic light emitting layer of the OLED is for each corresponding color. Even if it deteriorates at different speeds, it prevents the brightness of each color from being out of balance and displays the desired color. be able to.

In addition, the temperature of the organic light emitting layer may be affected by the outside air temperature or the heat generated by the OLED panel itself. , It is possible to suppress the change in the brightness of the OLED, and the power consumption increases as the temperature rises. It can be prevented from growing. Also, in the case of a color display light emitting device, it depends on the temperature change. Since it is possible to suppress the change in the brightness of the OLED of each color without doing so, the brightness of each color is balanced. Can be prevented from collapsing and a desired color can be displayed.

Further, in the light emitting device of the present invention, when measuring the OLED current, a table is displayed contrary to the intention of the user. It is very convenient because it is not necessary to change the displayed screen.

In a general light emitting device, the wiring that supplies current to each pixel (power line in Fig. 1) itself is a resistance. Therefore, the potential drops slightly depending on the length of the wiring. And this drop in potential is It also varies greatly depending on the image to be displayed. In particular, multiple pixels that receive current from the same wiring As the proportion of pixels with a high number of gradations increases, the current flowing through the wiring increases and the potential increases. The descent of is noticeable. When the potential drops, the voltage applied to the OLED of each pixel is small. Therefore, the current supplied to each pixel becomes small. Therefore, in a predetermined pixel Even if you try to display a constant gradation, the number of gradations of other pixels to which current is supplied from the same wiring As a result, the current supplied to the predetermined pixel changes accordingly, and as a result, the number of gradations also changes. Change. However, in the light emitting device of the present invention, the measured value and the reference value are obtained for each image to be displayed, and the OL Since the ED current can be corrected, the desired gradation can be corrected even if the displayed image changes. The number can be displayed.

In the present invention, the current may be corrected arbitrarily at any time by the user. It may be automatically performed when it is decided in advance by the setting.

Hereinafter, examples of the present invention will be described.

<p num="0055"> In this embodiment, an image is displayed using a digital video signal (digital video signal). A more detailed configuration of the correction circuit 108 shown in FIG. 5 of the light emitting device will be described.</p><p num="0056"> FIG. 6 shows the configuration of the correction circuit 108 of this embodiment as a block diagram. The correction circuit 108 is an electric circuit. It has a flow value calculation circuit 120, a current value comparison circuit 121, and a power supply control circuit 122.</p><p num="0057"> The current value calculation circuit 120 includes a counter circuit 123, a division circuit 124, and an A / D conversion circuit. It has 129 and a reference current value register 125. Obtained in ammeter 107 The measured value data is converted to digital by the A / D conversion circuit 129, and the division circuit 12 Entered in 4. The measured value obtained by the ammeter 107 is not analog but digital. If this is the case, it is not necessary to provide the A / D conversion circuit 129.</p><p num="0058"> The digital video signal input to the current value calculation circuit 120 is sent to the counter circuit 123. Entered. In the counter circuit 123, the appearance of a pulse of the input digital video signal From this period, the number of pixels emitting light when the current value is measured is calculated. The number of pixels is excluded It is sent as data to the arithmetic circuit 124.</p><p num="0059"> In the division circuit 124, each image that emits light is based on the input measured value and the number of pixels that are emitting light. Calculate the value of the current flowing through the OLED (pixel measurement value). Pixel measurement value is data Then, it is input to the current value comparison circuit 121.</p><p num="0060"> The current value comparison circuit 121 includes the subtraction circuit 126, the tolerance value register 127, and the comparison times. It has a road 128.</p><p num="0061"> The pixel measurement value input to the current value comparison circuit 121 is input to the subtraction circuit 126. on the other hand , The reference current value register 125 contains the ideal OLED current value (reference value) for each pixel. It is remembered. The reference value may be fixed data determined by the design of the mask or the like. , The data may be rewritable by a CPU, DIP switch, or the like.</p><p num="0062"> The reference value stored in the reference current value register 125 is input to the subtraction circuit 126. .. Then, in the subtraction circuit 126, the pixel measurement value input from the division circuit 124 and the reference value are Calculate the difference (hereinafter, deviation current).</p><p num="0063"> The deviation current is input to the comparison circuit 128 as data. On the other hand, paired with power lines V1 to Vx If the voltage between the counter electrodes that changes due to the correction is used as the correction voltage, the tolerance value register A value that determines the range of the deviation current without voltage correction is stored in the data 127. Voltage The correction of is performed many times until the deviation current converges within this range. Temporarily by voltage correction If the deviation current becomes completely 0, the tolerance value register 127 does not have to be provided. However, in reality, the measurement variation of the ammeter 107 and the calculation error in the subtraction circuit 126 Deviation current often continues to fluctuate minutely due to differences, noise, and the like. In this case, the deviation current Allowed to prevent meaningless repeated voltage corrections according to small fluctuations in Provide an error value register 127 to determine the range of deviation current values without voltage correction. Is extremely effective. It should be noted that the tolerance value register 127 is biased without voltage correction. In addition to the range of the difference current value, the value of the correction voltage corresponding to the deviation current value may be stored. .. The relationship between the deviation current and the correction voltage is shown, for example, as shown in FIG. In Fig. 7, the deviation current is constant. The correction voltage changes with a certain magnitude each time it changes with the width of.</p><p num="0064"> The relationship between the deviation current and the correction voltage does not necessarily have to follow the graph shown in Fig. 7. I. The deviation current and correction voltage are such that the value of the current actually flowing through the ammeter approaches the reference value. Any relationship is fine. For example, the deviation current and the correction voltage may have a linear relationship. The deviation current may be proportional to the square of the correction voltage.</p><p num="0065"> The relationship between the deviation current and the correction voltage stored in the tolerance value register 127 is a mask, etc. It may be fixed data determined by the design of, or it depends on the CPU, DIP switch, etc. The data may be rewritable.</p><p num="0066"> In the comparison circuit 128, the deviation current data input from the subtraction circuit 126 is the permissible error value. It should be out of the range of the deviation current value stored in the register 127 without voltage correction. If so, the correction voltage of a predetermined value is input to the power supply control circuit 122 as data. It should be noted that The value of the predetermined correction voltage is predetermined in the comparison circuit 128, and the deviation current corrects the voltage. When it is out of the range where it is not performed, the value of the predetermined correction voltage is set to the power supply control circuit 122. Make sure to enter in.</p><p num="0067"> The power supply control circuit 122 controls the variable power supply 106 based on the input correction voltage value. As a result, the voltage between the power supply lines V1 to Vx and the counter electrode is corrected by the value of the correction voltage. Above structure Due to the formation, the OLED drive voltage is corrected in the OLED 105 of each pixel 102. , The OLED drive current approaches the desired magnitude.</p><p num="0068"> The OLED drive voltage may be corrected by controlling the potential on the power supply line side. However, it may be corrected by controlling the potential on the counter electrode side. Also, the potential on the power line side It may be corrected by controlling both the potential on the counter electrode side and the potential on the counter electrode side.</p><p num="0069"> Then, in the correction of the voltage in the correction circuit 108, the value of the deviation current is the register for the tolerance value. It is repeated many times until it converges within the range where the voltage stored in the data 127 is not corrected. ..</p><p num="0070"> As shown in FIG. 7, the value of the correction voltage corresponding to the value of the deviation current is the tolerance value register 1. When stored in 27, in comparison circuit 128, the deviation voltage input from subtraction circuit 126 Relationship between flow data and deviation current and correction voltage stored in the tolerance value register 127 The value of the correction voltage is determined by comparing with and. In this case, even if the deviation current value is large, The deviation current can be reduced with a small number of voltage corrections.</p><p num="0071"> Instead of the counter circuit 123, a full adder and a memory may be used in combination. I.</p><p num="0072"> Further, in this embodiment, the subtraction circuit 126 is used, but how far the measured value and the reference value are from each other. Any circuit that can recognize whether or not it is used is sufficient. For example, a division circuit is used instead of the subtraction circuit 126. You may use it. When the division circuit is used, the ratio of the measured value to the reference value is calculated in the division circuit. To. Then, the value of the correction voltage is determined in the comparison circuit 128 from the ratio of the measured value and the reference value. Will be done.</p><p num="0073"> With the above configuration, the light emitting device of the present invention keeps the OLED current constant even if the organic light emitting layer deteriorates. Therefore, it is possible to suppress the decrease in brightness, and as a result, a clear image is displayed. Can be Further, in the light emitting device of the present invention, even if the temperature of the organic light emitting layer changes, OLE By correcting the D drive voltage, the OLED drive current can be kept constant at all times. Therefore, A constant brightness can be obtained regardless of temperature changes, and power consumption increases as the temperature rises. Can be prevented from becoming large. Further, in the light emitting device of the present invention, measurement is performed for each displayed image. Since the OLED current can be corrected by obtaining the constant value and the reference value, the displayed image changes. However, the desired number of gradations can be displayed by correction.</p><p num="0074"> The configuration of the correction circuit shown in this embodiment is only an example, and the present invention is limited to this configuration. I can't. The correction circuit used in the present invention is for the OLED drive current flowing through all or each pixel. A means of calculating an ideal value (reference value) from a video signal and a method of comparing a measured value with a reference value If there is a certain difference between the step and the measured value and the reference value, O to reduce the difference. It suffices to have a means for correcting the LED drive voltage.</p>

<p num="0075"> In this embodiment, the configuration of the correction circuit 108 shown in FIG. 5 different from that of the first embodiment will be described. To do.</p><p num="0076"> FIG. 8 shows the configuration of the correction circuit 108 of this embodiment as a block diagram. Correction circuit 1 of this embodiment In 08, the current value calculation circuit 120, the current value comparison circuit 121, and the power supply control circuit are the same as in the first embodiment. Has 122.</p><p num="0077"> The current value calculation circuit 120 includes a counter circuit 130, a reference current value register 131, and a power of the counter circuit 130. It has an arithmetic circuit 132 and an A / D conversion circuit 133. Obtained in ammeter 107 The measured value data is converted to digital by the A / D conversion circuit 133, and the current value comparison times. Entered on road 121. The measured value obtained by the ammeter 107 is not analog. If it is digital, it is not necessary to provide the A / D conversion circuit 133.</p><p num="0078"> The digital video signal input to the current value calculation circuit 120 is sent to the counter circuit 130. Entered. In the counter circuit 130, the appearance of a pulse of the input digital video signal From this period, the number of pixels emitting light when the current value is measured is calculated. The number of pixels is the power It is sent as data to the arithmetic circuit 132.</p><p num="0079"> On the other hand, the reference current value register 131 contains the ideal OLED current value (reference) for each pixel. Value) is memorized. Even if the reference value is fixed data determined by the design of the mask etc. The data may be rewritable by a CPU, DIP switch, or the like.</p><p num="0080"> The reference value stored in the reference current value register 131 is used as data in the multiplication circuit 132. Is entered in. In the multiplication circuit 132, from the input reference value and the number of emitting pixels, Calculate the reference value of the total of the OLED drive currents flowing through all the pixels.</p><p num="0081"> The total reference value calculated in the multiplication circuit 132 is the current value comparison circuit 12 as data. Entered in 1.</p><p num="0082"> Both the measured value input to the current value comparison circuit 121 and the total reference value data are subtraction circuit 1 Entered in 34. In the subtraction circuit 134, the difference between the input measured value and the total reference value data. (Hereinafter, deviation current) is calculated. The calculated deviation current is sent to the comparison circuit 137 as data. Entered.</p><p num="0083"> On the other hand, the tolerance value register 135 is used for correction between the power supply lines V1 to Vx and the counter electrode. Therefore, assuming that the voltage of the change is the correction voltage, the range of the deviation current without voltage correction is It is stored as a ratio to the total reference value. For voltage correction, the deviation current is within this range. It is done many times until it is bundled. If the deviation current becomes completely 0 due to the voltage correction, The tolerance value register 135 does not have to be provided. But in reality, the measurement of ammeter 107 The deviation current is very small due to the above variation, calculation error in the subtraction circuit 134, noise, etc. Often continues to fluctuate. In this case, the electric current is meaningless according to the minute fluctuation of the deviation current. In order to prevent repeated pressure correction, a tolerance value register 135 is provided to provide a voltage. It is extremely effective to determine the range of deviation current values that are not corrected for. In addition, permissible error In the difference value register 135, in addition to the range of the deviation current value without voltage correction, the deviation current The value of the correction voltage corresponding to the value may be stored. Deviation current and correction voltage are real on the ammeter The relationship may be such that the value of the current flowing at that time approaches the reference value. For example, deviation current and supplement The positive voltage may have a linear relationship, and the deviation current is proportional to the square of the correction voltage. You may.</p><p num="0084"> The relationship between the deviation current and the correction voltage stored in the tolerance value register 135 is a mask, etc. It may be fixed data determined by the design of, or it depends on the CPU, DIP switch, etc. The data may be rewritable.</p><p num="0085"> In the comparison circuit 137, the range of the deviation current without voltage correction is set to the tolerance value register. Calculated from the ratio of the total to the reference value stored in 135. And the subtraction circuit 1 If the deviation current data input from 34 is out of the range, the specified value is corrected. The voltage is input to the power supply control circuit 122 as data. The value of the predetermined correction voltage is predetermined in the comparison circuit 137, and the deviation current supplements the voltage. When it is out of the range where the positive is not performed, the value of the predetermined correction voltage is set to the power supply control circuit 1 Try to enter in 22.</p><p num="0086"> The power supply control circuit 122 controls the variable power supply 106 based on the input correction voltage value. As a result, the voltage between the power supply lines V1 to Vx and the counter electrode is corrected by the value of the correction voltage. Above structure Due to the formation, the OLED drive voltage is corrected in the OLED 105 of each pixel 102. , The OLED drive current approaches the desired magnitude.</p><p num="0087"> The OLED drive voltage may be corrected by controlling the potential on the power supply line side. However, it may be corrected by controlling the potential on the counter electrode side. Also, the potential on the power line side It may be corrected by controlling both the potential on the counter electrode side and the potential on the counter electrode side.</p><p num="0088"> Then, in the correction of the voltage in the correction circuit 108, the value of the deviation current is the register for the tolerance value. It is repeated many times until it converges within the range where the voltage stored in the data 135 is not corrected. ..</p><p num="0089"> The value of the correction voltage corresponding to the value of the deviation current is stored in the tolerance value register 135. If so, in the comparison circuit 137, the data of the deviation current input from the subtraction circuit 134 and Compare the relationship between the deviation current and the correction voltage stored in the tolerance value register 135. Then, the value of the correction voltage is determined. In this case, even if the deviation current value is large, the small voltage is compensated. The deviation current can be reduced by the number of positive times.</p><p num="0090"> Also, instead of the counter circuit 130, a full adder and a memory may be used in combination. I.</p><p num="0091"> Further, in this embodiment, the subtraction circuit 134 is used, but what is the measured value and the total reference value? Any circuit that can recognize whether it is far apart is sufficient, for example, division instead of subtraction circuit 134. A circuit may be used. When the division circuit is used, the measured value and the total reference value in the division circuit The ratio is calculated. Then, from the ratio of the measured value to the total reference value, in the comparison circuit 137 The value of the correction voltage is determined.</p><p num="0092"> With the above configuration, the light emitting device of the present invention keeps the OLED current constant even if the organic light emitting layer deteriorates. Therefore, it is possible to suppress the decrease in brightness, and as a result, a clear image is displayed. Can be Further, in the light emitting device of the present invention, even if the temperature of the organic light emitting layer changes, OLE By correcting the D drive voltage, the OLED drive current can be kept constant at all times. Therefore, A constant brightness can be obtained regardless of temperature changes, and power consumption increases as the temperature rises. Can be prevented from becoming large. Further, in the light emitting device of the present invention, measurement is performed for each displayed image. Since the OLED current can be corrected by obtaining the constant value and the reference value, the displayed image changes. However, the desired number of gradations can be displayed by correction.</p><p num="0093"> The configuration of the correction circuit shown in this embodiment is only an example, and the present invention is limited to this configuration. I can't. The correction circuit used in the present invention is for the OLED drive current flowing through all or each pixel. A means of calculating an ideal value (reference value) from a video signal and a method of comparing a measured value with a reference value If there is a certain difference between the step and the measured value and the reference value, O to reduce the difference. It suffices to have a means for correcting the LED drive voltage.</p>

<p num="0094"> In this embodiment, the light emitting device having the pixels shown in FIG. 4 is driven by using a digital video signal. The operation method and the timing of voltage correction will be described.</p><p num="0095"> The driving method of this embodiment will be described with reference to FIG. In Fig. 9, the horizontal axis is time. The vertical axis indicates the position of the pixel connected to each gate line.</p><p num="0096"> First, when the writing period Ta is started, the potential of the counter electrode of the OLED 105 and the power supply line V The power potential of 1 to Vx is kept at the same height. And it is output from the gate line drive circuit 104. Of all the pixels (first line pixels) connected to the gate line G1 by the selection signal The switching TFT 110 is turned on.</p><p num="0097"> Then, the source line drive circuit 103 inputs 1 bit to the source line (S1 to Sx). The digital video signal of the first order is driven by TFT11 via switching TFT110. Input to the gate electrode of 1.</p><p num="0098"> Next, the switching TFT 110 of the first line pixel is turned off, and the first line pixel Similar to, the switch of the second line pixel connected to the gate line G2 by the selection signal The TFT 110 for running is turned on. Next, the first bit digital from the source line (S1 to Sx) The Talvideo signal is driven by the TF for driving via the switching TFT110 of the second line pixel. It is input to the gate electrode of T111.</p><p num="0099"> Then, in order, the first bit digital video signal is input to the pixels of all lines. all The period until the 1st bit digital video signal is input to the pixels of all lines is written. The period is Ta1. In this embodiment, the fact that a digital video signal is input to the pixels means that The gate of the driving TFT 111 where the digital video signal is driven via the switching TFT 110 It means that it is input to the electrode.</p><p num="0100"> When the writing period Ta1 ends, the display period Tr1 is set next. In display period Tr1, oncoming power The pole potential is high enough to have a potential difference from the power supply potential of the power supply line to the extent that the OLED emits light. become.</p><p num="0101"> And in this embodiment, when the digital video signal has the information of "0", the driving T The FT111 is in the off state. Therefore, the power potential is given to the pixel electrodes of the OLED105. I can't. As a result, the pixel to which the digital video signal having the information of "0" is input has OLED105 does not emit light.</p><p num="0102"> On the contrary, if the information of "1" is possessed, the driving TFT 111 is in the ON state. .. Therefore, the power supply potential is given to the pixel electrodes of the OLED 105. As a result, the information of "1" The OLED 105 of the pixel to which the digital video signal is input emits light.</p><p num="0103"> In this way, the OLED 105 is in a light emitting or non-light emitting state during the display period Tr1. Therefore, all pixels are displayed. The period during which the pixels are displaying is called the display period Tr. in particular The display period that starts when the 1st bit digital video signal is input to the pixel is called Tr1. Call.</p><p num="0104"> When the display period Tr1 ends, the writing period becomes Ta2, and the potential of the counter electrode of the OLED is displayed again. The power potential of the power line becomes the same height. And all the games in order as in the case of writing period Ta1 The grid line is selected and the second bit digital video signal is input to all pixels. All of Write the period until the second bit digital video signal is input to the pixel of the line. Called period Ta2.</p><p num="0105"> When the writing period Ta2 ends, the display period Tr2 is set, and the potential of the counter electrode is emitted by the OLED. The height becomes such that there is a potential difference between the power supply potential and the power supply potential of the power supply line. And all the pixels display.</p><p num="0106"> The above operation is repeated until the nth bit digital video signal is input to the pixel. Then, the writing period Ta and the display period Tr appear repeatedly. All display periods (Tr1 ~ Tr When n) is finished, one image can be displayed. Table one image in the specification The period shown is called the one-frame period (F). When one frame period ends, the next frame period The interval is started. Then, the writing period Ta1 appears again, and the above-mentioned operation is repeated.</p><p num="0107"> In a normal light emitting device, it is preferable to provide a frame period of 60 or more per second. 1 second When the number of images displayed in is less than 60, the flickering of the images begins to be noticeable visually. Sometimes.</p><p num="0108"> In this embodiment, the sum of the lengths of all the writing periods is shorter than the one-frame period, and The length ratio of the display period is Tr1: Tr2: Tr3: ...: Tr (n-1): Trn = 2⁰:2¹ :2²:...:2^(n-2):2^(n-1)It is necessary to be. Set of this display period 2 in totalⁿIt is possible to display a desired gradation among the gradations.</p><p num="0109"> By finding the sum of the lengths of the display period during which the OLED emitted light during one frame period The gradation displayed by the pixel in the frame period is determined. For example, when n = 8, all Assuming that the brightness when the pixel emits light during the display period of the part is 100%, in Tr1 and Tr2 When the pixel emits light, 1% brightness can be expressed, and when Tr3, Tr5, and Tr8 are selected. Can express 60% brightness.</p><p num="0110"> The display periods Tr1 to Trn may appear in any order. For example, 1 frame During the period, the display period is displayed in the order of Tr1, Tr3, Tr5, Tr2, ... It is also possible to make it appear.</p><p num="0111"> Next, the timing of current measurement and digital bidet to correct the OLED drive voltage. The timing of calculating the reference value from the o signal will be described.</p><p num="0112"> In this embodiment, a digital video signal is transmitted to each pixel during the writing period Ta1 to Tan. In parallel with being written, a digital video signal is also input to the current value calculation circuit. Soshi Then, as shown in Example 1 or Example 2, an image that emits light from a digital video signal. The number of elements is calculated in a counter circuit or the like.</p><p num="0113"> Then, using the number of emitting pixels, the pixel measurement value in Example 1 is used as the basis in Example 2. The quasi-value is calculated.</p><p num="0114"> And the timing to measure the current is the line in the display period Tr1 to Trn in this embodiment. ing. However, the timing at which each display period starts differs depending on the pixels of each line. ing. Therefore, after all the pixels have started the display period, and all the pixels When the display period is not over, the total of OLED currents in all pixels is summed up all at once. It is important to measure.</p><p num="0115"> The driving method shown in this embodiment is only an example, and the present invention shown in FIGS. 1 and 4 is shown in FIG. The driving method of the light emitting device is not limited to the driving method of this embodiment.</p><p num="0116"> Further, the configuration of the correction circuit shown in this embodiment is only an example, and the present invention is limited to this configuration. I can't. The correction circuit used in the present invention is for the OLED drive current flowing through all or each pixel. A means of calculating an ideal value (reference value) from a video signal and a method of comparing a measured value with a reference value If there is a certain difference between the step and the measured value and the reference value, O to reduce the difference. It suffices to have a means for correcting the LED drive voltage.</p><p num="0117"> It should be noted that this embodiment can be carried out in any combination with Example 1 or 2.</p>

<p num="0118"> In this embodiment, a pixel configuration different from that in FIG. 4 of the light emitting device of the present invention will be described.</p><p num="0119"> FIG. 10 shows the pixel configuration of this embodiment. Pixels 300 are included in the pixel portion of the light emitting device of this embodiment. Are provided in a matrix. Pixel 300 has a source line 301 and a first gate line 302. , 2nd gate line 303, power supply line 304, switching TFT305, drive TFT30 6. Has TFT309 and OLED307 for erasing.</p><p num="0120"> Then, the gate electrode of the switching TFT 305 is connected to the first gate wire 302. There is. The source area and drain area of the switching TFT 305 are the source line 30 on one side. One is connected to the gate electrode of the driving TFT 306.</p><p num="0121"> The gate electrode of the erasing TFT 309 is connected to the second gate wire 303. TF for erasing The source area and drain area of the T309 are one for the power supply line 304 and the other for the drive TF. It is connected to the gate electrode of T306.</p><p num="0122"> The source area of the drive TFT 306 is the power line 304, and the drain area is the OLED 307. It is connected to the pixel electrode. Capacitor 308 is the gate electrode and power supply of the driving TFT 306. It is formed between the wire 304 and the wire 304.</p><p num="0123"> The power line 304 is connected to the variable power supply 311 via an ammeter 310. In addition, OL All counter electrodes of the ED307 are connected to the variable power supply 311. Note that the variable power supply 3 is shown in Fig. 10. 11 is maintained at a high potential (Vdd) on the power supply line side and at a low potential (Vss) on the counter electrode side. It is connected like. However, the present invention is not limited to this configuration, and the variable power supply 311 is OLE. It suffices if the current flowing through D307 is connected so as to have a forward bias.</p><p num="0124"> The position where the ammeter 310 is installed must be between the variable power supply 311 and the power supply line 304. It may be between the variable power supply 311 and the counter electrode.</p><p num="0125"> And 312 is a correction circuit, the value of the current measured by the ammeter 310 (measured value) Controls the voltage supplied from the variable power supply 311 to the counter electrode and the power supply line 304 based on ..</p><p num="0126"> The ammeter 310, the variable power supply 311, and the correction circuit 312 are based on the pixels. It may be formed on a substrate different from the board and connected to the pixel portion via a connector or the like. If it can be manufactured, it may be formed on the same substrate as the pixel portion.</p><p num="0127"> In the case of the colorized display method, a variable power supply and ammeter are provided for each color, and the OLED for each color is equipped. Then, the OLED drive voltage may be corrected. At this time, the correction circuit is for each color. It may be provided, or a correction circuit common to OLEDs of a plurality of colors may be provided.</p><p num="0128"> Next, a method of driving the light emitting device of this embodiment will be described. About the driving method of this embodiment , FIG. 11 will be described. In FIG. 11, the horizontal axis is time and the vertical axis is in contact with each gate line. Indicates the position of the subsequent pixels.</p><p num="0129"> First, when the writing period Ta1 is started, the first gate line of the first line is selected, Switch of all pixels (pixels of the first line) connected to the first gate line of the first line The TFT 305 for running is turned on.</p><p num="0130"> Then, the first bit digital video signal input to all source signal lines 302 is It is input to the gate electrode of the driving TFT 306 via the switching TFT 305. So The drive TFT 306 is based on the "0" or "1" information contained in the digital video signal. The switching is controlled. OLED307 fires when drive TFT306 is off Does not shine. Conversely, the OLED307 emits light when the drive TFT306 is on.</p><p num="0131"> In this way, at the same time that the digital video signal is input to the pixels of the first line, the OLED The 307 is in a light emitting or non-light emitting state, and the pixel in the first line is in the display period Tr1. It should be noted that the timing at which the display period of the pixels of each line is started has a time difference. ..</p><p num="0132"> Next, the selection of the first gate line 302 of the first line is completed. And from the second line to the top The first gate line 302 of the latter line is selected in order, and the first line pixel in all pixels Similarly, one bit of digital video signal is input. And the smell of each line The display period Tr1 is started. In addition, Taimin that the display period of the pixel of each line starts. Each has a time lag. And the 1st bit digital video message for all pixels The period until the issue is input is the writing period Ta1.</p><p num="0133"> On the other hand, before or after the end of the write period Ta1, the first bit of the pixel is displayed. In parallel with the input of the digital video signal, the selection of the second gate line 303 of the first line is started. To. Then, all the pixels connected to the second gate line 303 of the first line (first line). (Pixels) for erasing TFT309 is turned on. And the power potential of the power supply line 304 is erased. It is given to the gate electrode of the driving TFT 306 via the driving TFT 309.</p><p num="0134"> When the power potential is applied to the gate electrode of the drive TFT 306, the drive TFT 306 is pressed. The potentials of the gate electrode and the source region become the same, and the gate voltage becomes 0V. Therefore, the drive TFT 306 is turned off. Therefore, the power potential becomes the pixel electrode of OLED307. It will not be given, and all OLED307s possessed by the first line pixel will be in a non-luminous state. ..</p><p num="0135"> The period during which the pixels do not display is called the non-display period Td. In the first line pixel, the second As soon as the gate line 303 is selected, the display period Tr1 ends and the non-display period Td1 is set. ..</p><p num="0136"> And when the selection of the second gate line 303 of the first line is completed, the last line from the second line The second gate line 303 of the inn is selected in order, and the non-display period Td1 starts in all pixels. Will be done. As with the display period, the timing at which the non-display period of each line starts is There is a gap. All 2nd gate lines Ge1 ~ Gey are selected and in all pixels The period until Td1 is started is the erasure period Te1.</p><p num="0137"> On the other hand, the write period starts again before or after the erase period Te1 ends. To. In the writing period Ta2 that appears next, the second bit digital video signal is applied to all pixels. Entered. When the second bit digital video signal is input to the pixels of each line, Display period Tr2 starts.</p><p num="0138"> The above operation is repeated until the nth bit digital video signal is input to the pixel. Then, the display period Tr and the non-display period Td appear repeatedly. The display period is the writing period If it is longer than, another display period may appear consecutively after the display period.</p><p num="0139"> The display period is the write period or non-display that appears next after the write period is started. The period until the period starts. In addition, the non-display period is the next after the deletion period is started. It is the period until the writing period that appears in is started.</p><p num="0140"> When all the display periods are over, one image can be displayed. In the present invention The period during which one image is displayed is called the one-frame period (F).</p><p num="0141"> And after the end of one frame period, the writing period of the next frame period is started again, and above The described operation is repeated.</p><p num="0142"> In this embodiment, it is important that the sum of the lengths of all write periods is shorter than the one-frame period. Is. Moreover, the length of the display period is Tr1: Tr2: Tr3: ...: Tr (n-1): Tr n = 2⁰:2¹:2²:...:2^(n-2):2^(n-1)It is necessary to. This display period set 2 in the matchⁿIt is possible to display a desired gradation among the gradations.</p><p num="0143"> By finding the sum of the lengths of the display period during which the OLED emitted light during one frame period The gradation displayed by the pixel in the frame period is determined. For example, when n = 8, all Assuming that the brightness when the pixel emits light during the display period of the part is 100%, in Tr1 and Tr2 When the pixel emits light, 1% brightness can be expressed, and when Tr3, Tr5, and Tr8 are selected. Can express 60% brightness.</p><p num="0144"> The display periods Tr1 to Trn may appear in any order. For example, 1 frame During the period, the display period is displayed in the order of Tr1, Tr3, Tr5, Tr2, ... It is also possible to make it appear.</p><p num="0145"> Next, the structure of the correction circuit in the light emitting device of this embodiment and the OLED drive voltage are corrected. Therefore, the timing of measuring the current and the timing of calculating the reference value from the digital video signal. Will be described.</p><p num="0146"> The correction circuit of this embodiment is a circuit that calculates the number of emitting pixels from a digital video signal. The configuration is different from the correction circuit of the first embodiment or the second embodiment only in the mechanism of. In other words, the truth In Example 1 or 2, the number of pixels emitting light is counted using only the counter circuit. However, in this embodiment, in addition to the counter circuit, a memory reset circuit and a pulse counter The number of pixels emitting light is counted using the memory and the addition circuit. In this embodiment , Includes memory reset circuit, pulse counter memory and adder circuit in addition to counter circuit The circuit for counting the number of emitting pixels is called a pixel counter circuit for convenience. Bu.</p><p num="0147"> FIG. 12 shows a block diagram of the configuration of the pixel counter circuit 300 of this embodiment. The pixel count counter circuit 300 includes a counter circuit 301, a pulse counter memory 303, and an addition. It has an arithmetic circuit 304. The correction circuit of this embodiment is the correction circuit 1 shown in FIG. 6 or FIG. In 08, the counter circuit 123 or 130 of the current value calculation circuit 120 is pixelated. It corresponds to the one replaced with the number counter circuit 300 as it is.</p><p num="0148"> In the pulse counter memory 303, for each pixel of each line connected to the same gate line. , Corresponding storage location is provided. Hereinafter, in the present specification, the location where the memory is stored is described. Called a block. If there are y gate lines, y or more blocks must be provided. Each bu Locks are numbered 303_1 to 303_y for each corresponding line.</p><p num="0149"> In this embodiment, a digital video signal is transmitted to each pixel during the writing period Ta1 to Tan. In parallel with being written, a digital video signal is also input to the pixel counter circuit 300. Is done. Then, in each writing period, the digital video signal has the number of pixels in order for each line. It is input to the unter circuit 300.</p><p num="0150"> For example, at the same time that the digital video signal is input to the pixels of the first line, the first line A digital video signal that has the same image information as the digital video signal input to the pixels of It is input to the counter circuit 301 of the prime number counter circuit 300. However, although the signal is input to the pixels of the first line by the parallel processing method, the counter circuit 3 A signal is input to 01 by a serial processing method.</p><p num="0151"> In the counter circuit 301, the first line emits light based on the input digital video signal. Calculate the number of pixels. The calculated number of pixels is 1 of the pulse counter memory 303. It is stored in the third block 303_1.</p><p num="0152"> Below, the digital video signals corresponding to the pixels of the 2nd to yth lines are also countered in order. It is input to the road 301. And similarly, the number of emitting pixels of each line is calculated, and the pair It is stored in the corresponding blocks 303_2 to 303_y, respectively.</p><p num="0153"> The number of pixels stored in each block is always input to the adder circuit 304. Addition times On the road 304, the total value of the number of pixels of each input block is calculated. The calculated total number of emitting pixels is sent as data to the subsequent circuit. In particular , In FIG. 6, it is input to the division circuit 124, and in FIG. 8, it is input to the multiplication circuit 132.</p><p num="0154"> On the other hand, if the display period is shorter than the write period, the erase period is before the end of the write period. Will be started. In this case, the number of emitting pixels is always 0, so the erasing period is By the memory reset circuit 302 in order from the block corresponding to the pixel of the started line. Data with 0 pixels is stored.</p><p num="0155"> FIG. 13 shows the operation of the pulse counter memory 303 when this erasing period is started. I will explain in detail. In FIG. 13, j is an arbitrary number from 3 to y.</p><p num="0156"> FIG. 13 (A) shows after the write period has started and before the erase period has started. , The operation of the pulse counter memory 303 is shown. Write from counter circuit 301 Data on the number of emitting pixels is input to each block in order from the line where the period started. Will be retained.</p><p num="0157"> FIG. 13 (B) shows the pulse counter when the erase period is started during the write period. The operation of the memory 303 is shown. The write period is started from the counter circuit 301. Data on the number of emitting pixels is input to and held in each block in order from the line. So It is held in each block in order from the line where the erasure period started, so that it will follow after that. The data of the number of emitting pixels is the data of the number of pixels 0 from the memory reset circuit 302. It has been rewritten as data.</p><p num="0158"> Figure 13 (C) shows the data after the writing period has expired and before the erasing period has expired. The operation of the memory 303 for the ruth counter is shown. Luminous light held in each block Memory reset circuit 30 in order from the line where the erasing period is started for the data of the number of pixels It has been rewritten to data with 0 pixels from 2.</p><p num="0159"> Then, the timing of measuring the OLED current of each pixel is displayed by the pixel of any line. It is good if it is during the period.</p><p num="0160"> With the above configuration, in the correction circuit of this embodiment, when the display period is shorter than the write period. Also, the correction voltage can be adjusted by calculating and comparing the reference value and the measured value.</p><p num="0161"> The pixel configuration shown in this embodiment is only an example, and the present invention is not limited to this configuration.</p><p num="0162"> Further, the configuration of the correction circuit shown in this embodiment is only an example, and the present invention is limited to this configuration. Not determined. The correction circuit used in the present invention is an OLED drive electric power flowing through all or each pixel. Compare the measured value with the reference value with the means to calculate the ideal value (reference value) of the flow from the video signal. If there is a certain difference between the measured value and the reference value, reduce the difference. It suffices to have a means for correcting the OLED drive voltage.</p><p num="0163"> The light emitting device having the pixels shown in this embodiment is the supplement shown in Example 1 or Example 2. The normal circuit may be used as it is. In this case, when all the pixels are in the display period, Measure the current, calculate the number of pixels that are emitting light using the video signal, and make corrections. ..</p>

<p num="0164"> In this embodiment, an analog video signal (an analog video signal) is used for a light emitting device having pixels having the configuration shown in FIG. Hereinafter, the configuration of the correction circuit when driven by using an analog video signal) will be described.</p><p num="0165"> FIG. 14 shows a block diagram of the configuration of the correction circuit of this embodiment. Correction circuit 403 of this embodiment Has a current value calculation circuit 404, a current value comparison circuit 408, and a power supply control circuit 412.</p><p num="0166"> The current value calculation circuit 404 includes a voltage value calculation circuit 405 and a reference current-voltage ratio register 406. It has a multiplication circuit 407 and an A / D conversion circuit 413. Obtained with ammeter 401 The measured value data is converted to digital by the A / D conversion circuit 413, and the current value is converted. It is input to the comparison circuit 408. The measured value obtained by the ammeter 401 is analog. There is no need to provide an A / D conversion circuit 413 if it is digital.</p><p num="0167"> The analog video signal input to the current value calculation circuit 404 is the voltage value calculation circuit 405. Is entered in. In the voltage value calculation circuit 405, the power of the analog video signal input to each pixel The total pressure value is calculated. The voltage value is sent as data to the multiplication circuit 407.</p><p num="0168"> On the other hand, the reference current-voltage ratio register 406 has an OL for the OLED drive voltage of each pixel. The ideal value (voltage-current ratio) of the ED current is stored. The voltage-current ratio is the setting of masks, etc. It may be fixed data determined by the total, or written by CPU, DIP switch, etc. The data may be replaceable.</p><p num="0169"> The voltage-current ratio stored in the reference current-voltage ratio register 410 is multiplied as data. Entered on road 407. In the multiplication circuit 407, the input voltage-current ratio and the input to each pixel are input. From the total voltage value of the analog video signal, the sum of the OLED drive currents flowing through all the pixels Calculate the reference value of the total.</p><p num="0170"> The reference value calculated in the multiplication circuit 407 is input to the current value comparison circuit 408 as data. Be empowered.</p><p num="0171"> Both the measured value and the reference value data input to the current value comparison circuit 408 are sent to the subtraction circuit 409. Entered. In the subtraction circuit 409, the difference between the input measured value and the reference value data (hereinafter, deviation). Current) is calculated. The calculated deviation current is input to the comparison circuit 411 as data.</p><p num="0172"> On the other hand, the tolerance value register 410 is used for correction between the power supply lines V1 to Vx and the counter electrode. Therefore, assuming that the voltage corresponding to the change is the correction voltage, the value of the correction voltage corresponding to the value of the deviation current is recorded. It is remembered. The deviation current and correction voltage are based on the value of the current actually flowing through the ammeter 401. Any relationship that approaches the value will do. For example, the relationship between the deviation current and the correction voltage has linearity. It may be present, or the deviation current may be proportional to the square of the correction voltage.</p><p num="0173"> The relationship between the deviation current and the correction voltage stored in the tolerance value register 410 is a mask, etc. It may be fixed data determined by the design of, or it depends on the CPU, DIP switch, etc. The data may be rewritable.</p><p num="0174"> In the comparison circuit 411, the deviation current data input from the multiplication circuit 407 and the permissible error value. The value of the correction voltage is determined from the relationship between the deviation current and the correction voltage stored in the register 410. To do. Then, the value of the correction voltage is input to the power supply control circuit 412 as data.</p><p num="0175"> The power supply control circuit 412 controls the variable power supply 402 based on the input correction voltage value. As a result, the voltage between the power supply lines V1 to Vx and the counter electrode is corrected by the value of the correction voltage. Above structure Due to the formation, the OLED drive voltage is corrected in the OLED 105 of each pixel 102. , OLED drive current of desired magnitude flows.</p><p num="0176"> The OLED drive voltage may be corrected by controlling the potential on the power supply line side. However, it may be corrected by controlling the potential on the counter electrode side. Also, the potential on the power line side It may be corrected by controlling both the potential on the counter electrode side and the potential on the counter electrode side.</p><p num="0177"> Next, the detailed configuration of the voltage value calculation circuit 405 of this embodiment will be described. Figure 15 shows the electricity The configuration of the pressure value calculation circuit 405 is shown in a block diagram.</p><p num="0178"> The voltage value calculation circuit 405 is an A / D conversion circuit 414, a counter circuit 415, and a voltage value holding circuit. It has a memory 416 and an adder circuit 417.</p><p num="0179"> The voltage value holding memory 416 has a pair for each pixel of each line connected to the same gate line. A corresponding storage place (block) is provided. If there are y gate lines, block Must be provided in y or more. For each block, 416_1 ~ 416_ for each corresponding line Number y.</p><p num="0180"> In this embodiment, A / D conversion is performed in parallel with writing an analog video signal to each pixel. An analog video signal is also input to circuit 414. And in each writing period, Anna The log video signal is input to the A / D conversion circuit 414 in order for each line.</p><p num="0181"> For example, in parallel with the analog video signals being sequentially input to each pixel of the first line, 1 An analog bidet that has the same image information as the analog video signal input to each pixel of the line. The signal is input to the A / D conversion circuit 414. However, parallel processing is applied to the pixels of the first line. The signal is input by the physical method, but the signal is input to the A / D conversion circuit 414 by the serial processing method. Will be done.</p><p num="0182"> The analog video signal input to the A / D conversion circuit 414 is converted to digital and cowed. Input to the input circuit 415. Here is the reason why analog video signals are converted to digital This is because the memory 416 is easier to store in digital quantities. Therefore, memory 416 If it can be stored in analog quantity such as CCD or SH capacity, it is necessary to convert it to digital Absent.</p><p num="0183"> In the counter circuit 415, the first line image is based on the input digital video signal. Calculate the total of the raw OLED drive voltage. Calculated OLED drive power of the first line pixel The total pressure is stored in the first block 416_1 of the voltage value holding memory 416.</p><p num="0184"> Below, the analog video signals corresponding to the pixels of the 2nd to yth lines also change A / D in order. It is converted to digital in the conversion circuit 414 and input to the counter circuit 415. And the same As a result, the total OLED drive voltage is calculated for each line, and the corresponding block 416_2 ~ It is stored in 416_y respectively.</p><p num="0185"> The total OLED drive voltage stored in each block is always input to the adder circuit 417. It has been. In the addition circuit 417, the total of the input OLED drive voltages of each block is added up. Add up to calculate the total value. The calculated sum of the OLED drive voltages of all pixels is the multiplication circuit. Sent to 407 as data.</p><p num="0186"> When one frame period ends and an analog video signal for the next frame period is input, 1 Starting from the second block, the total data of the OLED drive voltage for the previous frame period is erased. Then, the total data of the OLED drive voltage for the next frame period is stored.</p><p num="0187"> Then, the timing of measuring the OLED current of each pixel is displayed by the pixel of any line. It is good if it is during the period.</p><p num="0188"> With the above configuration, the light emitting device of the present invention keeps the OLED current constant even if the organic light emitting layer deteriorates. Therefore, it is possible to suppress the decrease in brightness, and as a result, a clear image is displayed. Can be Further, in the light emitting device of the present invention, even if the temperature of the organic light emitting layer changes, OLE By correcting the D drive voltage, the OLED drive current can be kept constant at all times. Therefore, A constant brightness can be obtained regardless of temperature changes, and power consumption increases as the temperature rises. Can be prevented from becoming large. Further, in the light emitting device of the present invention, measurement is performed for each displayed image. Since the OLED current can be corrected by obtaining the constant value and the reference value, the displayed image changes. However, the desired number of gradations can be displayed by correction.</p><p num="0189"> The configuration of the correction circuit shown in this embodiment is only an example, and the present invention is not limited to this configuration. I. The correction circuit used in the present invention is an ideal OLED drive current flowing through all or each pixel. A means for calculating the value (reference value) to be used from the video signal, and a means for comparing the measured value with the reference value. , If there is some difference between the measured value and the reference value, OLE to reduce the difference It suffices to have a means for correcting the D drive voltage.</p><p num="0190"> In this embodiment, the analog video signal input to the current value calculation circuit 404 is a gun. This is the signal before correction. Current value calculation circuit 4 for analog video signal after gamma correction When inputting to 04, return the analog video signal to the potential before gamma correction, and then voltage. Input to the value calculation circuit 405.</p><p num="0191"> Further, in this embodiment, the drive is performed in a region where the gate voltage and the drain current are substantially proportional to each other. Adjust the potential of the analog video signal so that the TFT can operate.</p>

<p num="0192"> In this embodiment, the source line drive times used to drive the pixel portion of the light emitting device of the present invention. The detailed configuration of the road and gate line drive circuits will be described.</p><p num="0193"> FIG. 16 shows a block diagram of the drive circuit of the light emitting device of this embodiment. Figure 16 (A) Is the source line drive circuit 601, the shift register 602, the latch (A) 603, and the latch. It has (B) 604.</p><p num="0194"> In the source line drive circuit 601, the clock signal (CLK) is sent to the shift register 602. And the start pulse (SP) is input. The shift register 602 sets these clocks. Timing signals are generated in sequence based on the signal (CLK) and start pulse (SP), Timing signals are sequentially input to the subsequent circuit through a buffer or the like (not shown).</p><p num="0195"> The timing signal from the shift register 602 is buffered and amplified by a buffer or the like. Because many circuits or elements are connected to the wiring to which the timing signal is input. Large load capacitance (parasitic capacitance). The timing signal rises due to this large load capacitance. This buffer is provided to prevent "blunting" of rising or falling. In addition, It is not always necessary to provide a ufffa.</p><p num="0196"> The timing signal buffered and amplified by the buffer is input to latch (A) 603. .. Latch (A) 603 has multiple stages of latches for processing digital video signals. ing. The latch (A) 603 is a source line drive circuit when the timing signal is input. Digital video signals input from the outside of the 601 are sequentially written and held.</p><p num="0197"> When a digital video signal is written to the latch (A) 603, the latch (A) 6 Digital video signals may be written to the latches of multiple stages of 03 in order. .. However, the present invention is not limited to this configuration. Multiple stages of latch (A) 603 Latch is divided into several groups, and each group can be digitally videoed in parallel at the same time. So-called split drive in which a signal is written may be performed. The number of groups at this time Is called the number of divisions. For example, if you divide the latch into groups for each of the four stages, you can divide it into four. It is said to be split drive.</p><p num="0198"> One digital video signal write to latches on all stages of latch (A) 603 The time until the end is called the line period. Actually, the horizontal blanking interval is added to the above line period. May include the added period in the line period.</p><p num="0199"> At the end of the one-line period, a Latch Signal is sent to Latch (B) 604. Entered. At this moment, the digital video written and held on the latch (A) 603 The signals are sent to the latch (B) 604 all at once, and the latch (B) Written and retained in the latches of all 604 stages.</p><p num="0200"> For latch (A) 603, which has finished sending the digital video signal to latch (B) 604, Based on the timing signal from the register 602, the digital video signal is written in order. It will be done next.</p><p num="0201"> During this first line period of the second order, it is written to and held in latch (B) 604. A digital video signal is input to the source line.</p><p num="0202"> FIG. 16B is a block diagram showing a configuration of a gate line drive circuit.</p><p num="0203"> The gate line drive circuit 605 has a shift register 606 and a buffer 607, respectively. There is. In some cases, it may have a level shift.</p><p num="0204"> In the gate line drive circuit 605, the timing signal from the shift register 606 is backed up. It is input to the fa 607 and is input to the corresponding gate line. One line of fraction on the gate line The TFT gate electrode of the element is connected. And the TFT of one line of pixels Since it must be turned on all at once, the buffer should be able to carry a large current. Used.</p><p num="0205"> The drive circuit shown in this embodiment is only an example. This example is the same as Examples 1 to 4. It can be implemented in any combination.</p>

<p num="0206"> In this embodiment, the appearance of the light emitting device of the present invention will be described with reference to FIG.</p><p num="0207"> FIG. 17 (A) is a top view of the light emitting device, and FIG. 17 (B) is A-A'of FIG. 17 (A). FIG. 17 (C) is a sectional view taken along the line B-B'of FIG. 17 (A).</p><p num="0208"> Pixel part 4002 provided on the board 4001, source line drive circuit 4003, and the first A sealing material 4009 is provided so as to surround the second gate wire drive circuits 4004a and b. Has been done. In addition, the pixel section 4002, the source line drive circuit 4003, and the first and second games A sealing material 4008 is provided on the wire drive circuits 4004a and b. Therefore, the picture Element part 4002, source line drive circuit 4003, and first and second gate line drive circuits 400 4a and b are filled with the substrate 4001, the sealing material 4009, and the sealing material 4008. Sealed with filler 4210.</p><p num="0209"> In addition, the pixel section 4002 provided on the board 4001 and the source line drive circuit 4003, and the first The first and second gate line drive circuits 4004a and b have a plurality of TFTs. Figure 17 In (B), it is typically included in the source line drive circuit 4003 formed on the base film 4010. TFTs for drive circuits (however, n-channel type TFTs and p-channel type TFTs are shown here. The drive TFT (controls the current to the OLED) included in the 4201 and the pixel section 4002. TFT) 4202 is illustrated.</p><p num="0210"> In this embodiment, the drive circuit TFT4201 has a p-channel type T manufactured by a known method. FT or n-channel TFT is used, and the driving TFT 4202 is manufactured by a known method. The p-channel type TFT is used. In addition, the pixel section 4002 has a drive TFT 420. A holding capacity (not shown) connected to the gate electrode of 2 is provided.</p><p num="0211"> Interlayer insulating film (flattening film) 4 on the drive circuit TFT4201 and drive TFT4202 Pixel electricity is formed on which 301 is formed and electrically connected to the drain of the driving TFT 4202. A pole (anode) 4203 is formed. Transparent conductivity with a large work function for the pixel electrode 4203 Membranes are used. As a transparent conductive film, a compound of indium oxide and tin oxide, an oxide-in A compound of zinc and zinc oxide, zinc oxide, tin oxide or indium oxide can be used. it can. Further, a transparent conductive film to which gallium is added may be used.</p><p num="0212"> Then, an insulating film 4302 is formed on the pixel electrode 4203, and the insulating film 4302 is a pixel. An opening is formed on the electrode 4203. In this opening, the pixel electrode 4203 An organic light emitting layer 4204 is formed on the top. The organic light emitting layer 4204 is a known organic light emitting material or Can use an inorganic luminescent material. In addition, low-molecular-weight (monomer-based) organic light-emitting materials There are materials and polymer-based (polymer-based) materials, but either one may be used.</p><p num="0213"> As a method for forming the organic light emitting layer 4204, a known vapor deposition technique or coating method technique may be used. The structure of the organic light emitting layer is a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer or an electron injection. The layers may be freely combined to form a laminated structure or a single layer structure.</p><p num="0214"> On the organic light emitting layer 4204, a conductive film having a light-shielding property (typically aluminum, copper, if Cathode 420 composed of a conductive film containing silver as a main component or a laminated film of them and another conductive film) 5 is formed. In addition, water and oxygen existing at the interface between the cathode 4205 and the organic light emitting layer 4204. It is desirable to eliminate as much as possible. Therefore, the organic light emitting layer 4204 has a nitrogen or noble gas atmosphere. It is necessary to devise a way to form the cathode 4205 by forming it in the surrounding air and keeping it out of contact with oxygen and moisture. It is important. In this embodiment, a multi-chamber type (cluster tool type) film forming apparatus is used. This enables the above-mentioned film formation. And the cathode 4205 is given a predetermined voltage. ing.</p><p num="0215"> As described above, the pixel electrode (anode) 4203, the organic light emitting layer 4204 and the cathode 4205 OLED4303 consisting of is formed. And an insulating film that covers the OLED4303 A protective film 4209 is formed on the 4302. Protective film 4209 is on OLED4303 It is effective in preventing oxygen and water from entering.</p><p num="0216"> 4005a is a routing wire connected to the power supply line, and is the source of the driving TFT 4202. It is electrically connected to the area. The routing wiring 4005a is the sealing material 4009 and the board 40. FPC that FPC4006 has through the anisotropic conductive film 4300, passing between 01 It is electrically connected to the wiring 4301.</p><p num="0217"> Sealing materials 4008 include glass, metal (typically stainless steel), and ceramics. Mixed materials and plastic materials (including plastic films) can be used. Pu As a rustic material, FRP (Fiberglass-Reinforced Pla) stics) board, PVF (polyvinyl fluoride) Using film, mylar film, polyester film or acrylic resin film Can be Also, sandwich the aluminum foil between PVC film and Mylar film. It is also possible to use a sheet having a structure.</p><p num="0218"> However, if the direction of light emission from the OLED is toward the cover material side, the cover material is not transparent. Must be. In that case, glass plate, plastic plate, polyester film or Uses a transparent material such as an acrylic film.</p><p num="0219"> In addition to the inert gas such as nitrogen and argon, the filler 4210 is cured by ultraviolet rays. Resin or thermosetting resin can be used, PVC (polyvinyl chloride), acrylic , Polyimide, Epoxy Resin, Silicone Resin, PVB (Polyvinyl Butyral) or E VA (Ethylene Vinyl Acetate) can be used. In this embodiment, nitrogen is used as a filler. I used the element.</p><p num="0220"> Also, the filler 4210 will adsorb hygroscopic substances (preferably barium oxide) or oxygen. Recess 400 on the surface of the sealant 4008 on the substrate 4001 side to keep it exposed to substances 7 is provided to place a hygroscopic substance or a substance 4207 capable of adsorbing oxygen. And hygroscopic Recessed cover material 4208 so that substances or substances that can adsorb oxygen 4207 do not scatter Hygroscopic substances or substances capable of adsorbing oxygen 4207 are retained in recess 4007 To. The concave cover material 4208 has a fine mesh shape and allows air and moisture to pass through. , Hygroscopic substances or substances that can adsorb oxygen 4207 are not allowed to pass through. Hygroscopic Deterioration of OLED4303 is suppressed by providing substance 4207 that can adsorb substances or oxygen. You can control it.</p><p num="0221"> As shown in FIG. 17 (C), at the same time as the pixel electrode 4203 is formed, the routing wiring 4 A conductive film 4203a is formed so as to be in contact with the 005a.</p><p num="0222"> Further, the anisotropic conductive film 4300 has a conductive filler 4300a. Board 4 By thermocompression bonding 001 and FPC4006, the conductive film 4203a on the substrate 4001 Wiring 4301 for FPC on FPC4006 and electric by conductive filler 4300a Is connected.</p><p num="0223"> The ammeter, variable power supply, and correction circuit of the light emitting device of the present invention are different from those of the substrate 4001. Formed on a substrate (not shown) and on substrate 4001 via FPC4006 It is electrically connected to the power supply line and cathode 4205.</p><p num="0224"> It should be noted that this embodiment can be carried out in any combination with Examples 1 to 6.</p>

<p num="0225"> In this embodiment, the ammeter, the variable power supply, and the correction circuit included in the light emitting device of the present invention are provided in the pixel unit. Is formed on a substrate different from the substrate on which is formed, and the wire bonding method, COG (chitchi) Connect to the wiring on the board on which the pixel part is formed by means such as the p-on-glass method. An example will be described.</p><p num="0226"> FIG. 18 shows an external view of the light emitting device of this embodiment. Pixel section 50 provided on the substrate 5001 02, source line drive circuit 5003, and first and second gate line drive circuits 5004a, b A sealing material 5009 is provided so as to surround and. In addition, the pixel part 5002 and the saw Sea on the wire drive circuit 5003 and the first and second gate wire drive circuits 5004a, b A ring material 5008 is provided. Therefore, the pixel section 5002 and the source line drive circuit 500 3 and the first and second gate wire drive circuits 5004a and b are the substrate 5001 and the sealing material 5 Sealed with 009 and sealant 5008 along with filler (not shown).</p><p num="0227"> A hygroscopic substance or a hygroscopic substance is provided by providing a recess 5007 on the surface of the sealing material 5008 on the substrate 5001 side. Place a substance that can adsorb oxygen.</p><p num="0228"> The wiring (routed wiring) routed on the board 5001 is the sealing material 5009 and the substrate. Passes between the 5001 and connects to an external circuit or element of the light emitting device via the FPC5006. Has been done.</p><p num="0229"> The ammeter, variable power supply, and correction circuit of the light emitting device of the present invention are different from those of the substrate 5001. It is formed on a substrate (hereinafter referred to as a chip) 5020 and is a COG (chip on glass) method. A power supply line mounted on the board 5001 by means such as, etc., and formed on the board 5001. And is electrically connected to the cathode (not shown).</p><p num="0230"> In this embodiment, an ammeter, a variable power supply, and a chip 5020 in which a correction circuit is formed are used. By mounting on the board 5001 by the Yabonding method, COG method, etc., the light emitting device can be 1 It can be composed of a single substrate, which makes the device itself compact and increases its mechanical strength.</p><p num="0231"> As for the method of connecting the chip on the substrate, it is possible to use a known method. Is. In addition, the ammeter, variable power supply, and circuits and elements other than the correction circuit are mounted on the board 5001. You may attach it to.</p><p num="0232"> This embodiment can be carried out in any combination with Examples 1 to 7.</p>

<p num="0233"> In the present invention, an organic light emitting material capable of utilizing phosphorescence from triplet excitons for light emission is used. Therefore, the external emission quantum efficiency can be dramatically improved. This results in low OLED It enables power consumption, longer life, and lighter weight.</p><p num="0234"> Here, we show a report of improving the external emission quantum efficiency by using triplet excitons. (T.Tsutsui, C.Adachi, S.Saito, Photochemical Processes in Organized Molecular S ystems, ed.K.Honda, (Elsevier Sci.Pub., Tokyo, 1991) p.437.) </p><p num="0235">The molecular formulas of the organic light emitting materials (coumarin dyes) reported by the above papers are shown below.</p><p num="0236"><chemistry num="1"><img id="000002" he="50" wi="151" file="JP5771718B2_D0001.tif" img-format="tif" img-content="drawing" /></chemistry></p><p num="0237"> (MABaldo, DFO'Brien, Y.You, A.Shoustikov, S.Sibley, METhompson, SRForr est, Nature 395 (1998) p.151.) </p><p num="0238"> The molecular formulas of the organic light emitting materials (Pt complexes) reported by the above papers are shown below.</p><p num="0239"><chemistry num="2"><img id="000003" he="93" wi="151" file="JP5771718B2_D0001.tif" img-format="tif" img-content="drawing" /></chemistry></p><p num="0240"> (MABaldo, S.Lamansky, PEBurrrows, METhompson, SRForrest, Appl.Phys.Let t.,75 (1999) p.4.) (T.Tsutsui, M.-J.Yang, M.Yahiro, K.Nakamura, T.Watanabe, T.ts uji, Y.Fukuda, T.Wakimoto, S.Mayaguchi, Jpn.Appl.Phys., 38 (12B) (1999) L1502.)</p><p num="0241">The molecular formulas of the organic luminescent material (Ir complex) reported in the above paper are shown below.</p><p num="0242"><chemistry num="3"><img id="000004" he="93" wi="151" file="JP5771718B2_D0001.tif" img-format="tif" img-content="drawing" /></chemistry></p><p num="0243"> If phosphorescence from triplet excitons can be used as described above, in principle, from singlet excitons. It is possible to realize an external emission quantum efficiency that is 3 to 4 times higher than when using the fluorescence emission of.</p><p num="0244"> The configuration of this embodiment can be freely combined with any of the configurations of Examples 1 to 8. It is possible to carry out.</p>

<p num="0245"> An example of the method for manufacturing the light emitting device of the present invention will be described with reference to FIGS. 20 to 23. here Then, the switching TFT and the driving TFT of the pixel part are provided around the pixel part. The method of simultaneously manufacturing the TFT of the drive unit will be described in detail according to the process.</p><p num="0246"> First, in this embodiment, it is represented by Corning's # 7059 glass and # 1737 glass. Consists of glass such as barium borosilicate glass or aluminoborosilicate glass A substrate 900 is used. The substrate 900 is limited as long as it is a translucent substrate. Instead, a quartz substrate may be used. In addition, a plastic having heat resistance that can withstand the processing temperature of this example. A stick substrate may be used.</p><p num="0247"> Then, as shown in FIG. 20 (A), a silicon oxide film, a silicon nitride film or an acid is placed on the substrate 900. A base film 901 made of an insulating film such as a silicon nitriding film is formed. In this embodiment, the base film 901 A two-layer structure is used, but a single-layer film of the insulating film or a structure in which two or more layers are laminated is used. Is also good. As the first layer of the base film 901, the plasma CVD method is used, and SiH₄, NH₃, And And N₂Silicon oxide film 901a formed using O as a reaction gas is 10 to 200 nm (preferably). Or 50 to 100 nm). In this embodiment, the silicon oxide film 90 having a film thickness of 50 nm 1a (composition ratio Si = 32%, O = 27%, N = 24%, H = 17%) was formed. Then As the second layer of the base film 901, the plasma CVD method is used, and SiH₄, And N₂React O The silicon oxide film 901b formed as a gas is 50 to 200 nm (preferably 100 to 100). Laminated to a thickness of 150 nm). In this embodiment, a silicon oxide film with a film thickness of 100 nm 9 01b (composition ratio Si = 32%, O = 59%, N = 7%, H = 2%) was formed.</p><p num="0248"> Next, the semiconductor layers 902 to 905 are formed on the base film 901. Semiconductor layer 902 ~ 90 Reference numeral 5 denotes a known means (sputtering method, LPCVD method, or plastic film) for a semiconductor film having an amorphous structure. After film formation by Razuma CVD method, etc.), known crystallization treatment (laser crystallization method, thermal crystallization, etc.) A crystalline semiconductor film obtained by the method or a thermal crystallization method using a catalyst such as nickel). Is patterned into a desired shape. The thickness of the semiconductor layer 902 to 905 is 25 to 80 nm (preferably 30 to 60 nm). Form with. The material of the crystalline semiconductor film is not limited, but is preferably silicon. Is Silicon Germanium (Si_XGe_1-X(X = 0.0001 ~ 0.02)) Shaped with alloy etc. Good to do. In this example, a 55 nm amorphous silicon film is formed by using the plasma CVD method. After that, the solution containing nickel was held on the amorphous silicon film. Dehydrogenation on this amorphous silicon film After crystallization (500 ° C, 1 hour), thermal crystallization (550 ° C, 4 hours) is performed, and further crystallization is performed. A crystalline silicon film was formed by performing a laser animation treatment to improve the formation. And this Semiconductor layer 9 by patterning the crystalline silicon film of 02 ~ 905 was formed.</p><p num="0249"> Also, after forming the semiconductor layers 902 to 905, half to control the TFT threshold. The conductor layers 902 to 905 may be doped with trace amounts of impurity elements (boron or phosphorus). ..</p><p num="0250"> When a crystalline semiconductor film is produced by a laser crystallization method, a pulse oscillation type or a continuous type is used. Continuous emission type excimer laser, YAG laser, YVO₄Laser can be used .. When using these lasers, the laser light emitted from the laser oscillator is optically used. It is preferable to use a method of linearly condensing light with a system and irradiating the semiconductor film. The practitioner declares the conditions for crystallization It is a choice, but when using an excimer laser, the pulse oscillation frequency is 300 Hz. And the laser energy density is 100 ~ 400mJ / cm²(Typically 200 ~ 300m J / cm²). When using a YAG laser, the second harmonic is used for the pulse. The oscillation frequency is 30 to 300 kHz, and the laser energy density is 300 to 600 mJ / c. m²(Typically 350 ~ 500mJ / cm²). And width 100 ~ 1000μ A laser beam that is linearly focused at m, for example, 400 μm is irradiated over the entire surface of the substrate, and at this time. The superposition rate (overlap rate) of the linear laser light may be set to 50 to 90%.</p><p num="0251"> Next, the gate insulating film 906 covering the semiconductor layers 902 to 905 is formed. Gate insulating film 906 uses plasma CVD method or sputtering method, and silicon with a thickness of 40 to 150 nm. It is formed of an insulating film containing. In this example, the acid is produced at a thickness of 110 nm by the plasma CVD method. It was formed of a silicon nitriding film (composition ratio Si = 32%, O = 59%, N = 7%, H = 2%). Naughty In theory, the gate insulating film is not limited to the silicon oxide film, but simply an insulating film containing other silicon. It may be used as a layered or laminated structure.</p><p num="0252"> When a silicon oxide film is used, TEOS (Tetraethyl Ortho) is used by the plasma CVD method. silicate) and O₂The reaction pressure is 40 Pa, the substrate temperature is 300 to 400 ° C, and the circumference is high. Wave (13.56MHz) Power density 0.5 ~ 0.8W / cm²Can be formed by discharging with it can. The silicon oxide film thus produced is subsequently thermally annealed at 400 to 500 ° C. Therefore, good characteristics can be obtained as a gate insulating film.</p><p num="0253"> Then, the heat-resistant conductive layer 907 for forming the gate electrode on the gate insulating film 906 is 2 It is formed with a thickness of 00 to 400 nm (preferably 250 to 350 nm). Heat resistant conductive layer 9 07 may be formed in a single layer, or may be composed of multiple layers such as two or three layers as required. It may be a laminated structure. The heat-resistant conductive layer is an element selected from Ta, Ti, W, or the front An alloy containing the above elements as a component or an alloy film in which the above elements are combined is included. These heat resistance The conductive layer is formed by a sputtering method or a CVD method, and is contained in order to reduce the resistance. It is preferable to reduce the impurity concentration, especially the oxygen concentration should be 30 ppm or less. Is good. In this example, a W film is formed with a thickness of 300 nm. W film targets W It may be formed by the sputtering method, or it may be formed by tungsten hexafluoride (WF).₆) By thermal CVD method It can also be formed. In any case, low resistance is required for use as a gate electrode. The resistivity of the W film should be 20 μΩcm or less. W film has crystal grains It is possible to reduce the resistivity by increasing the size, but there are many impurity elements such as oxygen in W. In some cases, crystallization is inhibited and resistance is increased. From this, in the case of the sputtering method, the purity is 9 Uses 9.9999% W target, and no impurities are mixed in the gas phase during film formation. A resistivity of 9 to 20 μΩcm should be achieved by forming a W film with due consideration. Can be done.</p><p num="0254"> On the other hand, when a Ta film is used for the heat-resistant conductive layer 907, it is similarly formed by a sputtering method. And is possible. Ar is used as the sputter gas for the Ta film. Also suitable for gas during sputtering By adding an amount of Xe or Kr, the internal stress of the film to be formed can be relaxed and the film can be prevented from peeling. Can be done. The resistivity of the α-phase Ta film is about 20 μΩcm and should be used for the gate electrode. However, the resistivity of the β-phase Ta film is about 180 μΩcm, which makes it unsuitable for use as a gate electrode. It was suitable. Since the TaN film has a crystal structure close to the α phase, a TaN film is formed under the Ta film. If formed, an α-phase Ta film can be easily obtained. Also, although not shown, under the heat-resistant conductive layer 907 It is possible to form a phosphorus (P) -doped silicon film with a thickness of about 2 to 20 nm. It is effective. As a result, the adhesion of the conductive film formed on the conductive film is improved and oxidation is prevented at the same time. In addition, the gate insulating film in which the alkali metal element contained in a trace amount of the heat-resistant conductive layer 907 has the first shape. It can be prevented from spreading to 906. In any case, the heat-resistant conductive layer 907 has a resistivity. Is preferably in the range of 10 to 50 μΩcm.</p><p num="0255"> Next, a resist mask 908 is formed using photolithography techniques. .. Then, the first etching process is performed. In this embodiment, an ICP etching apparatus is used. Cl for the gas for hatching₂And CF₄3.2W / cm at a pressure of 1Pa²RF (13.5 6MHz) Power is applied to form plasma. 224 mW / cm on the substrate side (sample stage)²RF (13.56MHz) power input As a result, a substantially negative self-bias voltage is applied. Etching of W film under these conditions The speed is about 100 nm / min. The first etching process is based on this etching rate. Estimate the time when the W film is just etched, and increase the etching time by 20%. The time that was allowed to be allowed was defined as the etching time.</p><p num="0256"> Conductive layers 909 to 912 having a first tapered shape are formed by the first etching process. Will be done. The angle of the tapered portion of the conductive layer 909 to 912 is formed to be 15 to 30 °. To. Etching at a rate of about 10 to 20% in order to etch without leaving a residue Overetching shall be applied to increase the time. Silicon oxide for W film Since the selection ratio of the film (gate insulating film 906) is 2 to 4 (typically 3), the over-equation The exposed surface of the silicon oxide film is etched by about 20 to 50 nm by the ching process. Is done. (Fig. 20 (B))</p><p num="0257"> Then, the first doping treatment is performed to add a one-conductive impurity element to the semiconductor layer. This Here, the step of adding an impurity element that imparts n-type is performed. The machine that formed the conductive layer of the first shape The conductive layers 909 to 912 having the first taper shape are masked, leaving the desk 908 as it is. An impurity element that self-aligns n-type is added by the ion doping method. Give n type Impurity elements are passed through the tapered portion at the end of the gate electrode and the gate insulating film 906. , Add 1x10 dose to reach the semiconductor layer below it¹³~5× 10¹⁴atoms / cm²Then, the acceleration voltage is set to 80 to 160 keV. Give n type Elements belonging to Group 15 as impurity elements, typically phosphorus (P) or arsenic (As) Although it is used, phosphorus (P) was used here. The first impurity by such an ion doping method 1x10 for areas 914-917²⁰~1×10²¹atomic / cm³With n type in the concentration range of The giving impurity element is added. (Fig. 20 (C))</p><p num="0258"> In this step, depending on the doping conditions, the conductive layer 909 in which impurities have the first shape. It wraps under ~ 912, and the first impurity region 914 ~ 917 is the conductive layer 909 of the first shape. It can also overlap with ~ 912.</p><p num="0259"> Next, a second etching process is performed as shown in FIG. 20 (D). Etching process is the same Performed by ICP etching equipment, CF to etching gas₄And Cl₂Using the mixed gas of RF power 3.2W / cm²(13.56MHz), bias power 45mW / cm²(13.56 Etching is performed at MHz) and pressure of 1.0 Pa. Has a second shape formed under these conditions Conductive layers 918 to 921 are formed. A tapered portion is formed at the end portion, and from the end portion It has a tapered shape with a gradual increase in thickness toward the inside. Compare with the first etching process As a result, the bias power applied to the substrate side is reduced, and the proportion of isotropic etching increases. The angle of the super part is 30 to 60 °. Mask 908 is etched and the edges are scraped, It becomes 922. Further, in the process of FIG. 20 (D), the surface of the gate insulating film 906 is 4 Etched at about 0 nm.</p><p num="0260"> Then, the dose amount is lower than that of the first doping treatment, and n-type is added under the condition of high acceleration voltage. Doping impurities. For example, set the acceleration voltage to 70 to 120 keV and set it to 1 x 10¹³/cm²The first impurity region 924 to 92 where the impurity concentration increased after the dose amount of 7 and the second impurity regions 928-931 in contact with the first impurity regions 924 to 927. To form. In this step, depending on the doping conditions, impurities lead to a second shape. It wraps under the electric layers 918 to 921, and the second impurity region 928 to 931 leads to the second shape. It may overlap with the electric layers 918 to 921. The impurity concentration in the second impurity region is , 1x10¹⁶~1×10¹⁸atoms / cm³To be. (Fig. 21 (A))</p><p num="0261"> Then, as shown in (FIG. 21 (B)), the semiconductor layer 90 forming the p-channel TFT is formed. In 2,905, the impurity regions of the conductive type, which is the opposite of the conductive type, 933 (933a, 933b) and 9 Form 34 (934a, 934b). In this case as well, the conductive layers of the second shape 918, 921 Is used as a mask to add an impurity element that imparts p-type to form an impurity region in a self-aligned manner. .. At this time, the semiconductor layers 903 and 904 forming the n-channel TFT are the masses of the resist. Form 932 and cover the entire surface. Impurity regions 933 and 934 formed here are Borane (B)₂H₆) Is formed by the ion doping method. P-type of impurity regions 933 and 934 The concentration of the impurity element that imparts 2 × 10²⁰~2×10²¹atoms / cm³To be To.</p><p num="0262"> However, these impurity regions 933 and 934 specifically contain impurity elements that impart n-type. It can be divided into two regions containing it. The third impurity regions 933a and 934a 1x10²⁰~1×10²¹atoms / cm³Contains impurity elements that impart n-type at the concentration of 4th impurity regions 933b and 934b are 1 × 10¹⁷~1×10²⁰atoms / cm³Concentration Contains impurity elements that impart n-type in degrees. However, these impurity regions 933b, 9 The concentration of the impurity element that imparts the p-type of 34b is 1 × 10.¹⁹atoms / cm³That's all In the third impurity region 933a and 934a, the impurity element that imparts p-type By increasing the concentration to 1.5 to 3 times the concentration of the impurity element that imparts n-type. Functions as the source and drain regions of the p-channel TFT in the third impurity region Therefore, no problem arises.</p><p num="0263"> Then, as shown in FIG. 21 (C), the conductive layers 918 to 921 having the second shape and A first interlayer insulating film 937 is formed on the gate insulating film 906. The first interlayer insulating film 937 is Silicon oxide film, silicon nitride film, silicon nitride film, or a combination of these It may be formed of a layered film. In any case, the first interlayer insulating film 937 is formed from an inorganic insulating material. To be done. The film thickness of the first interlayer insulating film 937 is 100 to 200 nm. First interlayer insulating film 9 When using a silicon oxide film as 37, TEOS and O by plasma CVD method₂And mixed Combined, the reaction pressure is 40 Pa, the substrate temperature is 300 to 400 ° C, and the high frequency (13.56 MHz) electricity is used. Force density 0.5 ~ 0.8W / cm²It can be formed by discharging with. Also, the first interlayer insulation When a silicon oxide nitride film is used as the film 937, SiH is used by the plasma CVD method.₄, N₂O, NH₃Silicon oxynitride film made from, or SiH₄, N₂Acid made from O It may be formed of a silicon nitriding film. The production conditions in this case are a reaction pressure of 20 to 200 Pa. Substrate temperature 300-400 ° C, high frequency (60MHz) power density 0.1-1.0W / cm²Formed by can do. In addition, SiH is used as the first interlayer insulating film 937.₄, N₂O, H₂Made from The silicon oxide hydrogenated silicon film to be used may be applied. Similarly for the silicon nitride film, plasma C SiH by VD method₄, NH₃It can be made from.</p><p num="0264"> Then, it activates the impurity element that imparts n-type or p-type added at each concentration. Perform the process. This step is performed by a thermal annealing method using a furnace annealing furnace. Other , Laser annealing, or rapid thermal annealing (RTA method) Can be done. In the thermal annealing method, the oxygen concentration is 1 ppm or less, preferably 0.1 ppm or less. It is carried out at 400 to 700 ° C, typically 500 to 600 ° C in a bare atmosphere. In the example, heat treatment was performed at 550 ° C for 4 hours. In addition, the substrate 501 has a low heat resistant temperature. When using a backing substrate, it is preferable to apply the laser annealing method.</p><p num="0265"> Following the activation process, the atmosphere gas is changed in an atmosphere containing 3-100% hydrogen. , Heat treatment is performed at 300 to 450 ° C for 1 to 12 hours to hydrogenate the semiconductor layer. This process is in the semiconductor layer with thermally excited hydrogen 10¹⁶~10¹⁸/cm³Dunglin This is the process of terminating the bond. As another means of hydrogenation, plasma hydrogenation (to plasma) (Using more excited hydrogen) may be performed. In any case, the semiconductor layer 902 to 90 Defect density in 5 is 10¹⁶/cm³It is desirable to use the following, and hydrogen is 0.01 to 0 for that purpose. About .1 atomic% should be given.</p><p num="0266"> Then, the second interlayer insulating film 939 made of an organic insulating material has an average of 1.0 to 2.0 μm. Formed by film thickness. Organic resin materials include polyimide, acrylic, polyamide, and polyimi. Doamide, BCB (benzocyclobutene) and the like can be used. For example, paint on the board When using a type of polyimide that heat-polymerizes after clothing, use a clean oven at 300 ° C. Formed by firing. When using acrylic, use a two-component type and cure it with the main material. After mixing the agent, apply it to the entire surface of the substrate using a spinner, and then use a hot plate at 80 ° C for 6 Preheat for 0 seconds and bake in a clean oven at 250 ° C for 60 minutes to form. Can be done.</p><p num="0267"> In this way, by forming the second interlayer insulating film 939 with the organic insulating material, the surface is formed. It can be flattened well. In addition, organic resin materials generally have a low dielectric constant, so they are parasitic. Capacity can be reduced. However, since it has hygroscopicity and is not suitable as a protective film, it is as in this example. In addition, the silicon oxide film, the silicon oxide nitride film, and the nitriding formed as the first interlayer insulating film 937. It is recommended to use it in combination with a silicon film or the like.</p><p num="0268"> After that, a resist mask having a predetermined pattern is formed, and the resist mask is formed on each semiconductor layer. A contact hole is formed to reach an impurity region as a loose region or a drain region. Ko The contact hole is formed by a dry etching method. In this case, CF is added to the etching gas.₄, O₂First, the second interlayer insulating film 939 made of an organic resin material is etched using a mixed gas of He and He. And then CF the etching gas₄, O₂As the first interlayer insulating film 937 To itch. Furthermore, in order to increase the selectivity with the semiconductor layer, the etching gas is CHF.₃By switching to and etching the gate insulating film 570 of the third shape, the contact lens Can be formed.</p><p num="0269"> Then, a conductive metal film is formed by a sputtering method or a vacuum vapor deposition method, and patterned with a mask. After that, by etching, the source wiring 940 ~ 943 and the drain wiring 944 ~ 94 Form 6. Although not shown, in this embodiment, this wiring is used, and T with a film thickness of 50 nm. It was formed by a laminated film of an i film and an alloy film having a film thickness of 500 nm (an alloy film of Al and Ti).</p><p num="0270"> Next, a transparent conductive film having a thickness of 80 to 120 nm is formed on the transparent conductive film and patterned. The pixel electrode 947 is formed by (Fig. 22 (A)). In this embodiment, the transparent electrode is used. Indium tin oxide (ITO) film and indium oxide with 2 to 20 [%] zinc oxide (Z) Use a transparent conductive film mixed with nO).</p><p num="0271"> Further, the pixel electrode 947 is driven by being formed in contact with the drain wiring 946 and overlapping. An electrical connection is formed with the drain area of the active TFT.</p><p num="0272"> Next, as shown in FIG. 22 (B), a second having an opening at a position corresponding to the pixel electrode 947. The interlayer insulating film 949 of 3 is formed. The third interlayer insulating film 949 has insulating properties and is a van. It functions as a function and has a role of separating the organic light emitting layers of adjacent pixels. In this example A third interlayer insulating film 949 is formed using a resist.</p><p num="0273"> In this embodiment, the thickness of the third interlayer insulating film 949 is about 1 μm, and the opening is the pixel electrode 9. It is formed so as to have a so-called reverse taper shape, which becomes wider as it gets closer to 47. This is After forming the gist, cover the area other than the part where the opening is to be formed with a mask and irradiate with UV light. It is formed by exposing and removing the exposed portion with a developing solution.</p><p num="0274"> By forming the third interlayer insulating film 949 into a reverse taper shape as in this embodiment, it can be used in a later process. When the organic light emitting layer is formed, the organic light emitting layer is divided between adjacent pixels. Even if the coefficient of thermal expansion of the machine light emitting layer and the third interlayer insulating film 949 are different, the organic light emitting layer is cracked. It is possible to prevent cracking and peeling.</p><p num="0275"> In this embodiment, a film made of resist is used as the third interlayer insulating film. , In some cases polyimide, polyamide, acrylic, BCB (benzocyclobutene) , Silicon oxide film and the like can also be used. The third interlayer insulating film 949 is a substance having insulating properties. If there is, either an organic substance or an inorganic substance may be used.</p><p num="0276"> Next, the organic light emitting layer 950 is formed by a vapor deposition method, and further, a cathode (MgAg electrode) is formed by a vapor deposition method. ) 951 and protective electrode 952 are formed. At this time, the organic light emitting layer 950 and the cathode 951 are Prior to formation, the pixel electrode 947 is heat-treated to completely remove water. Is desirable. In this example, the MgAg electrode is used as the cathode of the OLED, but it is known. It may be another material.</p><p num="0277"> A known material can be used as the organic light emitting layer 950. Positive in this example Hole transporting layer and Emitting layer The two-layer structure consisting of is an organic light emitting layer, but there is no hole injection layer, electron injection layer or electron transport layer. There may be a gap. In this way, various examples of combinations have already been reported. Any of the above configurations may be used.</p><p num="0278"> In this embodiment, polyphenylene vinylene is formed as a hole transport layer by a vapor deposition method. Also As a light emitting layer, polyvinylcarbazole and P of 1,3,4-oxadiazole derivative A BD with 30-40% molecular dispersion is formed by the vapor deposition method and used as a green light emitting center. About 1% of Marine 6 is added.</p><p num="0279"> In addition, the protective electrode 952 can also protect the organic light emitting layer 950 from moisture and oxygen. However, it is more preferable to provide a protective film 953. In this example, as a protective film 953 A silicon nitride film having a thickness of 300 nm is provided. This protective film also does not release to the atmosphere after the protective electrode 952 It may be formed continuously with.</p><p num="0280"> In addition, the protective electrode 952 is provided to prevent deterioration of the cathode 951, and is mainly made of aluminum. A typical example is a metal film to be separated. Of course, other materials may be used. Also, organic light emitting layer 950, shade Since the pole 951 is very sensitive to moisture, it is continuously formed without releasing the protective electrode 952 to the atmosphere. However, it is desirable to protect the organic light emitting layer from the outside air.</p><p num="0281"> The film thickness of the organic light emitting layer 950 is 10 to 400 [nm] (typically 60 to 150 [nm]). The thickness of the cathode 951 may be 80 to 200 [nm] (typically 100 to 150 [nm]).</p><p num="0282"> In this way, a light emitting device having a structure as shown in FIG. 22 (B) is completed. The pixel electrode 947 , The overlapping portion 954 of the organic light emitting layer 950 and the cathode 951 corresponds to the OLED.</p><p num="0283"> The p-channel TFT960 and n-channel TFT961 are TFTs that the drive circuit has. Yes, forming CMOS. TFT962 for switching and TFT963 for driving It is the TFT of the pixel part, and the TFT of the drive circuit and the TFT of the pixel part are formed on the same substrate. can do.</p><p num="0284"> In the case of a light emitting device using OLED, the voltage of the power supply of the drive circuit is about 5 to 6 V, the maximum. However, about 10V is enough, so there is not much question about deterioration due to hot electrons in TFT. It doesn't matter. Also, since it is necessary to operate the drive circuit at high speed, the gate capacitance of the TFT is Smaller is preferable. Therefore, as in this embodiment, the drive rotation of the light emitting device using the OLED. In the road, the second impurity region 929 and the fourth impurity region 933 of the semiconductor layer of the TFT It is preferable that b does not overlap with the gate electrodes 918 and 919, respectively.</p><p num="0285"> The manufacturing method of the light emitting device of the present invention is not limited to the manufacturing method described in this example. The light emitting device of the present invention can be manufactured by using a known method.</p><p num="0286"> It should be noted that this embodiment can be carried out in any combination with Examples 1 to 9.</p>

<p num="0287"> In this embodiment, a method of manufacturing a light emitting device different from that of the tenth embodiment will be described.</p><p num="0288"> The process up to forming the second interlayer insulating film 939 is the same as in Example 5. Figure 23 (A ), After forming the second interlayer insulating film 939, it comes into contact with the second interlayer insulating film 939. As a result, the passivation film 939 is formed.</p><p num="0289"> In the passivation film 939, the moisture contained in the second interlayer insulating film 939 is contained in the pixel electrode 9 Effective in preventing entry into the organic light emitting layer 950 via 47 or the third interlayer insulating film 982. Is. When the second interlayer insulating film 939 has an organic resin material, the organic resin material has moisture. It is particularly effective to provide the passivation film 939 because it contains a large amount of the passivation film 939.</p><p num="0290"> In this example, a silicon nitride film was used as the passivation film 939.</p><p num="0291"> After that, a resist mask having a predetermined pattern is formed, and the resist mask is formed on each semiconductor layer. A contact hole is formed to reach an impurity region as a loose region or a drain region. Ko The contact hole is formed by a dry etching method. In this case, CF is added to the etching gas.₄, O₂First, the second interlayer insulating film 939 made of an organic resin material is etched using a mixed gas of He and He. And then CF the etching gas₄, O₂As the first interlayer insulating film 937 To itch. Furthermore, in order to increase the selectivity with the semiconductor layer, the etching gas is CHF.₃By switching to and etching the gate insulating film 570 of the third shape, the contact lens Can be formed.</p><p num="0292"> Then, a conductive metal film is formed by a sputtering method or a vacuum vapor deposition method, and patterned with a mask. After that, by etching, the source wiring 940 ~ 943 and the drain wiring 944 ~ 94 Form 6. Although not shown, in this embodiment, this wiring is used, and T with a film thickness of 50 nm. It was formed by a laminated film of an i film and an alloy film having a film thickness of 500 nm (an alloy film of Al and Ti).</p><p num="0293"> Next, a transparent conductive film having a thickness of 80 to 120 nm is formed on the transparent conductive film and patterned. The pixel electrode 947 is formed by (Fig. 23 (A)). In this embodiment, the transparent electrode is used. Indium tin oxide (ITO) film and indium oxide with 2 to 20 [%] zinc oxide (Z) Use a transparent conductive film mixed with nO).</p><p num="0294"> Further, the pixel electrode 947 is driven by being formed in contact with the drain wiring 946 and overlapping. An electrical connection is formed with the drain area of the active TFT.</p><p num="0295"> Next, as shown in FIG. 23 (B), a second having an opening at a position corresponding to the pixel electrode 947. The interlayer insulating film 982 of 3 is formed. In this embodiment, when forming the opening, wet etching A tapered side wall was formed by using the ang method. Unlike the case shown in Example 5, the third Since the organic light emitting layer formed on the interlayer insulating film 982 is not divided, the side wall of the opening is sufficient. If it is not gentle, the deterioration of the organic light emitting layer due to the step becomes a remarkable problem. Caution must be taken.</p><p num="0296"> In this embodiment, a film made of silicon oxide is used as the third interlayer insulating film 982. However, in some cases, polyimide, polyamide, acrylic, BCB (benzocyclobu) An organic resin film such as ten) can also be used.</p><p num="0297"> Then, before forming the organic light emitting layer 950 on the third interlayer insulating film 982, the third interlayer is interrupted. The surface of the peripheral film 982 is subjected to plasma treatment using argon, and the table of the third interlayer insulating film 982 is applied. It is preferable to make the surface dense. With the above configuration, organic from the third interlayer insulating film 982 It is possible to prevent moisture from entering the light emitting layer 950.</p><p num="0298"> Next, the organic light emitting layer 950 is formed by a vapor deposition method, and further, a cathode (MgAg electrode) is formed by a vapor deposition method. ) 951 and protective electrode 952 are formed. At this time, the organic light emitting layer 950 and the cathode 951 are Prior to formation, the pixel electrode 947 is heat-treated to completely remove water. Is desirable. In this example, the MgAg electrode is used as the cathode of the OLED, but it is known. It may be another material.</p><p num="0299"> A known material can be used as the organic light emitting layer 950. Positive in this example Hole transporting layer and Emitting layer The two-layer structure consisting of is an organic light emitting layer, but there is no hole injection layer, electron injection layer or electron transport layer. There may be a gap. In this way, various examples of combinations have already been reported. Any of the above configurations may be used.</p><p num="0300"> In this embodiment, polyphenylene vinylene is formed as a hole transport layer by a vapor deposition method. Also As a light emitting layer, polyvinylcarbazole and P of 1,3,4-oxadiazole derivative A BD with 30-40% molecular dispersion is formed by the vapor deposition method and used as a green light emitting center. About 1% of Marine 6 is added.</p><p num="0301"> In addition, the protective electrode 952 can also protect the organic light emitting layer 950 from moisture and oxygen. However, it is more preferable to provide a protective film 953. In this example, as a protective film 953 A silicon nitride film having a thickness of 300 nm is provided. This protective film also does not release to the atmosphere after the protective electrode 952 It may be formed continuously with.</p><p num="0302"> In addition, the protective electrode 952 is provided to prevent deterioration of the cathode 951, and is mainly made of aluminum. A typical example is a metal film to be separated. Of course, other materials may be used. Also, organic light emitting layer 950, shade Since the pole 951 is very sensitive to moisture, it is continuously formed without releasing the protective electrode 952 to the atmosphere. However, it is desirable to protect the organic light emitting layer from the outside air.</p><p num="0303"> The film thickness of the organic light emitting layer 950 is 10 to 400 [nm] (typically 60 to 150 [nm]). The thickness of the cathode 951 may be 80 to 200 [nm] (typically 100 to 150 [nm]).</p><p num="0304"> In this way, a light emitting device having a structure as shown in FIG. 23 (B) is completed. The pixel electrode 947 , The overlapping portion 954 of the organic light emitting layer 950 and the cathode 951 corresponds to the OLED.</p><p num="0305"> The p-channel TFT960 and n-channel TFT961 are TFTs that the drive circuit has. Yes, forming CMOS. TFT962 for switching and TFT963 for driving It is the TFT of the pixel part, and the TFT of the drive circuit and the TFT of the pixel part are formed on the same substrate. can do.</p><p num="0306"> The manufacturing method of the light emitting device of the present invention is not limited to the manufacturing method described in this example. The light emitting device of the present invention can be manufactured by using a known method.</p><p num="0307"> It should be noted that this embodiment can be carried out in any combination with Examples 1 to 9.</p>

<p num="0308"> Since the light emitting device used in the electronic device of the present invention is a self-luminous type, it is compared with a liquid crystal display. It has excellent visibility in bright places and has a wide viewing angle. Therefore, it is used for the display of various electronic devices. Can be</p><p num="0309"> As the electronic device of the present invention, a video camera, a digital camera, a goggle type display ( Head-mounted display), navigation system, sound reproduction device (car audio) E, audio components, etc.), notebook personal computers, game machines, mobile information edges Ends (mobile computers, mobile phones, handheld game consoles, e-books, etc.), recording media Plays back recording media such as the built-in image playback device (specifically, DVD: Digital Versatile Disc) However, a device equipped with a display capable of displaying the image) and the like can be mentioned. Especially diagonally Since the wide viewing angle is important for mobile information terminals, which often look at the screen from the direction, the light emitting device It is desirable to use a device. Specific examples of these electronic devices are shown in FIG.</p><p num="0310"> FIG. 24A shows the organic light emitting display device of the present invention, which includes the housing 2001, the support base 2002, and the table. Includes display 2003, speaker 2004, video input terminal 2005, etc. Light emission of the present invention The device can be used for the display unit 2003. Since the light emitting device is a self-luminous type, it is backlit. The display unit can be thinner than the liquid crystal display without the need for a display. In addition, organic light emission The display device is a display device for displaying all information such as for personal computers, for receiving TV broadcasts, and for displaying advertisements. Is included.</p><p num="0311"> FIG. 24B shows the digital still camera of the present invention, which is the main body 2101 and the display unit 2102. , Image receiving part 2103, operation key 2104, external connection port 2105, shutter 2106, etc. including. The light emitting device of the present invention can be used for the display unit 2102.</p><p num="0312"> FIG. 24 (C) shows the notebook personal computer of the present invention, which includes the main body 2201 and the housing. 2202, display 2203, keyboard 2204, external connection port 2205, pointy Includes Ngmouth 2206 and others. The light emitting device of the present invention can be used for the display unit 2203. ..</p><p num="0313"> FIG. 24 (D) shows the mobile computer of the present invention, which is the main body 2301 and the display unit 2302. , Switch 2303, operation key 2304, infrared port 2305, etc. Light emission of the present invention The device can be used for the display unit 2302.</p><p num="0314"> FIG. 24 (E) shows the portable image playback device of the present invention provided with a recording medium (specifically, DVD reproduction). Raw device), main body 2401, housing 2402, display unit A2403, display unit B2404, Recording medium (DVD, etc.) Reading unit 2405, operation key 2406, speaker unit 2407, etc. including. The display unit A2403 mainly displays image information, and the display unit B2404 mainly displays sentences. Character information is displayed, but the light emitting device of the present invention is used for these display units A, B2403, and 2404. Can be The image playback device equipped with a recording medium also includes home-use game machines and the like. Is done.</p><p num="0315"> FIG. 24 (F) shows the goggle type display (head-mounted display) of the present invention. Includes the main body 2501, the display 2502, and the arm 2503. The light emitting device of the present invention displays It can be used for part 2502.</p><p num="0316"> FIG. 24 (G) shows the video camera of the present invention, which includes a main body 2601, a display unit 2602, and a housing 2. 603, external connection port 2604, remote control receiver 2605, image receiver 2606, battery -Includes 2607, voice input unit 2608, operation keys 2609, etc. The light emitting device of the present invention displays Can be used in part 2602.</p><p num="0317"> Here, FIG. 24 (H) shows the mobile phone of the present invention, which includes a main body 2701, a housing 2702, and a display unit. 2703, audio input unit 2704, audio output unit 2705, operation key 2706, external connection port Includes 2707, antenna 2708, etc. The light emitting device of the present invention is used for the display unit 2703. Can be done. The display unit 2703 displays white characters on a black background to display a mobile phone. Power consumption can be suppressed.</p><p num="0318"> If the emission brightness of the organic light emitting material becomes high in the future, the light including the output image information will be emitted. It is also possible to magnify and project with a projector and use it for front type or rear type projectors. Become.</p><p num="0319"> In addition, the above electronic devices are used for electronic communication such as the Internet and CATV (cable TV). More often the information delivered through the line is displayed, especially the opportunity to display video information I'm doing it. Since the response speed of organic light emitting materials is very high, light emitting devices are preferred for moving image display. I.</p><p num="0320"> In addition, since the light emitting part of the light emitting device consumes power, the light emitting part is reduced as much as possible. It is desirable to display the information as such. Therefore, mobile information terminals, especially mobile phones and sound reproduction When a light emitting device is used for a display unit that mainly uses character information such as a device, the non-light emitting portion is used as the background. It is desirable to drive the character information so as to be formed by the light emitting portion.</p><p num="0321"> As described above, the scope of application of the present invention is extremely wide, and it can be used for electronic devices in all fields. It is possible. Further, the electronic device of this embodiment has a light emitting device having any configuration shown in Examples 1 to 11. You may use a table.</p>