A display device and method for manufacturing thereof

Display device and its manufacturing method

The present invention relates to a display device using an organic light-emitting device. The display device has an anode, a cathode, and an organic compound that emits light by applying an electric field (hereinafter referred to as an organic thin film). Specifically, the present invention relates to a high-reliability display device driven by a low voltage. The organic thin film contains an organic compound as a light-emitting material, and may also contain an inorganic compound as other constituent elements. The term display device in this specification refers to an image display device that uses an organic light-emitting device as the light-emitting device. The definition of display device also includes: module, in which connectors such as anisotropic conductive film (FPC, that is flexible printed circuit), TAB (Tape Automatic Bonding) tape, or TCP (Tape Carrier Package) The connector of) is fixed to the module of the organic light-emitting device; the module in which the printed circuit board is provided on the TAB tape or the end of the TCP; and the IC (integrated circuit) is directly mounted by the COG (chip on glass) method To the module of the organic light-emitting device.

When an electric field is applied, the organic light emitting device emits light. The light-emitting mechanism is described below. A voltage is applied to the organic film sandwiched between the electrodes, causing electrons injected from the cathode and holes injected from the anode to recombine in the organic film, and the excited molecules (hereinafter referred to as molecular excitons) return due to In the ground state, it releases energy and emits light.

There are two types of molecular excitons from organic compounds; one is singlet excitons and the other is triplet excitons. This specification includes two cases where singlet excitation causes luminescence and triplet excitation causes luminescence.

In the organic light-emitting device as described above, the organic thin film is usually made to a thickness of less than 1 micron. In addition, since the organic light-emitting device is a self-light-emitting device, the light itself is emitted from the organic thin film, so the backlight required by the conventional liquid crystal display is not required. Therefore, the significant advantage of the organic light emitting device is that it is very thin and light.

For example, when the thickness of the organic thin film is about 100-200 nm, according to the mobility of the carriers in the organic thin film, recombination occurs within several tens of nanoseconds after the carriers are injected. Considering the process from carrier recombination to light emission, the organic light-emitting device is ready to emit light within a few microseconds. Therefore, quick response is also one of the advantages of organic light emitting devices.

Since the organic light-emitting device is a carrier injection type, it can be driven by a DC voltage and generates little noise. Regarding the driving voltage, it is reported that using an ultra-thin organic film with a uniform thickness of about 100nm, selecting an electrode material that can reduce the carrier injection barrier of the organic film, and further introducing a heterojunction structure (double-layer structure) at 5.5V Obtained 100cd/m²(Reference 1: CWTang and SA Vanslyke, "Organic electroluminescent diodes", Applied Physics Letters, vol. 51, no. 12, 913-915 (1987)).

It can be considered that the feature of the organic light-emitting device described in Reference 1 is the separation of the functions of the hole transport layer and the electron transport light-emitting layer. The hole transport layer is specified to transport holes and the electron transport light-emitting layer is specified. Transmission of electrons and light. The idea of functional separation has been developed in the double heterojunction structure (three-layer structure), in which the light-emitting layer is sandwiched between the hole transport layer and the electron transport layer (Reference 2: Chihaya ADACHI, Shizuo TOKITO, Tetsuo TSUTSUI, and Shogo Saito, "Electroluminescence in Organic Films with Three-Layered Structure", Japanese Journal of Applied Physics, vol. 27, No. 2, L269-L271 (1988)) .

The advantage of functional separation is that since it is not necessary to provide various functions (luminescence, carrier transport, and carrier injection from the electrode) for an organic material at the same time, it expands the freedom of molecular design (for example, it makes it unnecessary to search for bipolar materials. ). In other words, by combining a material with excellent light-emitting characteristics and a material with excellent carrier transport ability, high light-emitting efficiency can be easily obtained.

Regarding the separation of functions, the concept of a cathode buffer layer and an anode buffer layer is proposed to introduce a carrier injection function to reduce the driving voltage. It is reported that by inserting a material that lowers the energy barrier into the interface between the cathode and its organic film to enhance carrier injection, the driving voltage is reduced (Reference 3: Takeo Wakimoto, Yoshinori Fukuda, Kenichi Nagayama, Akira Yokoi, Hitoshi Nakada, and Masami Tsuchida, "Organic EL Cells Using Alkaline Metal Compounds as Electron Injection Materials", IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 44, NO. 8, 1245-1248 (1997)). In Reference 3, it is disclosed that Wakimoto et al. used Li₂O acts as a cathode buffer layer to reduce the driving voltage. (Organic EL element using alkali metal recombination as electron injection material)

Regarding the buffer layer, a polymer-containing buffer layer has received particular attention in recent years (Reference 4: Yoshiharu Sato, Molecular Electronics and Bioelectronics (The Japan Society of Applied Physics), vol. 11, No. 1, 86-99 (2000)) . In Reference 4, it is disclosed that the use of an anode buffer layer containing a polymer promotes lower voltage, longer life, and higher heat resistance. Since the conductivity is improved by introducing appropriate receptors, the anode buffer layer containing the polymer can be made thick. As a result, flatness can be improved, and it is expected that short circuits can be reduced.

Taking advantage of these features, including thinner and lighter, fast response, and DC low-voltage drive, organic light-emitting devices are attracting attention as the next generation of flat panel display devices. In addition, because it is a self-luminous type and has a wide viewing angle, organic light-emitting devices have better visibility, and are therefore considered to be particularly suitable for display screens for in-vehicle products and portable devices. Organic light-emitting devices are actually used in specific area color displays of car audio.

Another feature of organic light emitting devices is to emit light of various colors. A variety of excellent colors are obtained from the diversity of its own organic compounds. In other words, due to its flexibility, a variety of colors can be obtained, and with the help of molecular design (for example, the introduction of substitutes), materials that emit different colors can be developed.

Based on this, it can be said that the most promising application of organic light-emitting devices lies in full color displays, not to mention monochrome and specific range displays. Various methods have been proposed to display full colors while considering the characteristics of organic light emitting devices. Currently, there are three main methods for manufacturing full-color displays with organic light-emitting devices. One of these main methods is to use shadow mask technology to separately produce red light emitting organic light emitting devices, green light emitting organic light emitting devices, and blue light emitting organic light emitting devices. Red, green, and blue are the three primary colors of light, and each of the three organic light-emitting devices forms a pixel. Hereinafter, this method is referred to as the RGB method. Another main method uses a blue organic light-emitting device as a light emitting source to obtain the three primary colors of light, and converts blue light into green light and red light through a color conversion layer made of organic fluorescent materials. Hereinafter, this method is referred to as the CCM method. The last method is to obtain the three primary colors by emitting white light from a white organic light emitting device used as a light emitting source through a color filter used in a liquid crystal display device or the like. Hereinafter, this method is referred to as the CF method.

In any of these structures, driving methods such as passive matrix driving (simple matrix type) and active matrix driving (active matrix type) are used for display devices formed by arranging organic light-emitting devices in a matrix of pixels . In addition, in the case of increased pixel density, it should be said that the active matrix type that provides switches (for example, a non-linear element such as a transistor) in each pixel is superior to the passive matrix type because it can be driven at a low voltage.

At the same time, as described above, the polymer-containing buffer layer described in Reference 4 promotes lower voltage, longer life, and higher heat resistance. When trying to use an organic light-emitting device having a buffer layer (mainly an anode buffer layer) containing these materials by means of being arranged in a matrix of individual pixels of a display device, problems have occurred. This problem is crosstalk.

In most buffer layers containing polymers, a donor or acceptor is added to the polymer containing the π-conjugated system in order to give it conductivity. This polymer is usually applied to the entire surface by spin coating or the like, which causes current overflow and leakage between the polymer and the wiring.

For example, it has been reported that the use of conductive polymer polydihydroxythiophene ethylene/polystyrene sulfonic acid (hereinafter referred to as "PEDT/PSS") with receptors as the anode buffer layer is used to form a passive matrix display device, causing Crosstalk (Reference 5: A. Elschner, F. Jonas, S. Kirchmeyer, K. Wussow, "High-Resistivity PEDT/PSS for Reduced Crostalk in Passive Matrix OELs" PEDT/PSS)", Asia Display/IDW'01,1427-1430(2001)). In Reference 5, it is described that the resistivity of PEDT/PSS is made higher in order to avoid crosstalk.

However, if the resistivity is made high, the polymer-containing buffer layer cannot be made into a thick film (that is, the current does not easily pass through the organic light-emitting device). Therefore, the characteristic of avoiding short circuit caused by thickening the film to smooth the surface of the electrode is lost. The high resistivity spontaneously leads to a high driving voltage. As a result, the advantage of low driving voltage is also lost.

Therefore, the object of the present invention is to apply a conductive buffer layer using a polymer to a display device composed by arranging organic light-emitting elements as pixels in a matrix form without causing crosstalk. With the above method, it is also a problem to provide a display device with low driving voltage, excellent reliability and heat resistance, and few short-circuit defects.

Moreover, it is a problem to provide electronic appliances with low power consumption and long life by manufacturing using this display device.

The present invention is a display device having a plurality of pixels arranged in a matrix, which includes: a substrate; a plurality of first electrodes provided on an insulating surface of the substrate and corresponding to the plurality of pixels; An insulating dam above the surface of an electrode; an organic conductor film provided on the insulating dam and the first electrode; an organic thin film provided on the organic conductive film and containing an organic compound capable of causing electroluminescence; and a first provided on the organic thin film Two electrodes.

Specifically, the organic conductive film is characterized by containing a high polymer added with an acceptor or a donor body. Moreover, considering the flatness, the organic conductive film is preferably a film made by a wet method. The wet method can be a spin coating process, an inkjet process, or a spray process. By the way, the conductivity of the organic conductive film is preferably 10^-6S/cm or above and 10^-2S/cm or less.

At the same time, the insulating dam is characterized by a tapered shape that gradually decreases toward the top of the base. In this case, the taper angle of the tapered shape is preferably 60 degrees or more and 80 degrees or less. Moreover, in the case where the insulating dam has at least one curvature radius center on the edge line of the insulating dam on the base side, or the insulating dam has at least one curvature radius center on the edge line of the insulating dam on the base side and at the base When the opposite side of the side has a curved surface shape with at least one center of curvature radius to the edge line of the insulating dam, it can be particularly suitable for spin coating.

Moreover, in the present invention, the display device is characterized by further including a data signal line, a scanning signal line, and a non-linear element connected to the data signal line, the scanning signal line, and the first electrode. In this case, it is preferable to use a combination of a thin film transistor and a capacitor connected to each other or a combination of a thin film transistor and a parasitic capacitor of the thin film transistor to form a nonlinear element.

At the same time, as long as it is a display device, any surface of the display device must be sufficiently transparent to the visible part of the light. Therefore, the feature of the present invention is that the substrate and the first electrode are transparent to visible light, or the second electrode is transparent to visible light.

In the present invention, as a method of manufacturing the above-mentioned display device, a manufacturing process of a display device having a plurality of pixels arranged in a matrix includes: forming a pattern of a plurality of first electrodes corresponding to the plurality of pixels on an insulating surface of a substrate A step of forming an insulating bank that surrounds the first electrode and protruding on the surface of the first electrode; a step of providing an organic conductive film on the insulating bank and the first electrode; The step of forming an organic thin film of an organic compound; and the step of forming a second electrode on the organic thin film.

In the present invention, the step of providing an organic conductive film on the insulating dam and the first electrode is a wet process. In this case, the wet process is preferably a process of spray coating, spin coating, or ink-jet coating of the material solution or material suspension of the organic conductive film.

Moreover, in the present invention, the patterning process is characterized by the steps of forming data signal lines, scanning signal lines, and non-linear elements connected to the data signal lines, scanning signal lines, and the first electrode. In this case, it is preferable to use a combination of a thin film transistor and a capacitor connected to each other or a combination of a thin film transistor and a parasitic capacitor of the thin film transistor to form a nonlinear element.

Figure 1 shows a conceptual diagram of the present invention. In FIG. 1A, the insulating bank 103a is provided in a form surrounding the pixel portion 110a so as to form the first electrode 102a and the pixel 110a in a strip shape (vertically in the figure) on the substrate. Meanwhile, in FIG. 1B, the insulating bank 103b is provided in a form surrounding the pixel 110b so as to form the island-shaped first electrode 102b and the pixel portion 110b on the substrate. In any case, a cross-sectional view along the line A-A' in the figure is shown in Figure 1C. 101 is the substrate, 102 is the first electrode, and 103 is the insulating dam.

Various methods are known to make such a dam, as disclosed in JP-A-8-227276 (Reference 6). Reference 6 has a structure in which a plurality of first display electrodes are formed on the surface of a substrate, an electrically insulating barrier that surrounds the first display electrode and protrudes on the substrate, and at least one organic layer is formed on the first display electrode in the barrier. A thin film of electroluminescent medium and a second display electrode jointly fabricated on a plurality of electroluminescent medium films.

At this time, it is assumed that the entire surface is coated with an organic conductive film 104 represented by conductive polymer PEDOT/PSS or the like by a wet method. In this case, under the influence of the insulating bank 103, the thickness of the organic conductive film 104 has a form of T2>T1>T3. Therefore, the resistance of the T3 portion in the lateral direction increases, making it possible to prevent crosstalk. Also, since the thickness of the T2 portion is increased, the electric field intensity at and around the pixel portion is weakened. This makes it possible to prevent degradation of the organic light emitting element around the pixel.

When the organic conductive film is coated by a wet method, this form can be effectively obtained. However, when the organic conductive film is made by a dry process such as vacuum deposition, this form can be similarly obtained. Therefore, both dry and wet processes are effective in making the organic conductive film 104.

If applied to the passive matrix type, this concept provides the form shown in Figures 2A and 2B. Fig. 2A is a top view, and Fig. 2B is a cross-sectional view taken along the line BB' in Fig. 2A. That is, the strip-shaped first electrode 202 is fabricated on the substrate 201, and the insulating bank 203 is fabricated to protrude on the first electrode 202 and surround the pixel P. An organic conductive film 204 (represented by a conductive polymer) is provided, and an organic thin film 205 containing an organic compound capable of causing electroluminescence is further produced. The second electrode 206 is formed on it, orthogonal to the first electrode.

Note here that using a metal mask, the organic thin film 205 is separately coated on each pixel, showing a form suitable for full-color display. Of course, for single colors, continuous coating can be used instead of separate coating.

At the same time, if applied to the active matrix type, this concept provides the form of Figures 3A and 3B. Fig. 3A is a top view, and Fig. 3B is a cross-sectional view taken along the line CC' in Fig. 3A. That is, the island-shaped first electrode 302 is fabricated on the substrate 301, and the insulating bank 303 is fabricated to protrude on the first electrode 302 and surround the pixel. An organic conductive film 304 is provided thereon, and an organic thin film 305 containing an organic compound capable of causing electroluminescence is further fabricated. The second electrode 306 is formed thereon by a continuous coating method.

Furthermore, a data signal line 307, a scanning signal line 308, and a non-linear element 309 connected to the data signal line 307 and the scanning signal line 308 are provided. The non-linear element is connected to the first electrode 302 through the contact point 310. This enables individual pixels to be switched on and off. Typically, the non-linear element 309 is formed by a method of combining a thin film transistor and a capacitor connected to each other, or combining a thin film transistor and a parasitic capacitor of the thin film transistor.

By the way, in FIGS. 2 and 3, the structure of the organic thin film may adopt the structure of a known organic light-emitting element. Either of the first electrode and the second electrode may have visible light transparency. When the first electrode is an anode, the second electrode may be a cathode. When the first electrode is a cathode, the second electrode may be an anode.

For organic conductive films, proper coating is a method of providing dark conductivity by incorporating acceptors or donors into organic semiconductors. Regarding the film forming process, those using dry processes such as vacuum deposition, and those using wet processes such as spin coating are included.

As an example, the method of co-depositing low-molecular organic semiconductors and acceptors or donors is usually used to fabricate the organic conductive film to be fabricated by a dry process. An organic conductive film co-deposited with a p-type organic semiconductor and an acceptor is preferably used as a hole injection layer. An organic conductive film co-deposited with an n-type organic semiconductor and a donor is preferably used as an electron injection layer.

Low-molecular p-type organic semiconductors include 4,4'-bis[N-(1-naphthalene)-N-phenyl-amino]-biphenyl (abbreviated as α-NPD) and 4,4',4"-tri( N,N-diphenylamino)-triphenylamine (abbreviated as TDATA) and 4,4',4"-tris[N-(3-methylphenyl)-N-phenylamino]-triphenylamine (abbreviated as MTDATA) ) And other aromatic amine compounds. Low-molecular n-type organic semiconductors include, for example, tris(8-hydroxyline) aluminum (abbreviated as Alq3) and bis[2-(2-hydroxyphenyl)-benzoxazole] zinc (abbreviated as Zn(BOX)2) Class metal complexes, such as 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviated as PBD) and 1,3-bis [5-p-tert-butylphenyl]-1,3,4-oxadiazole-2-type] oxadiazole derivatives such as benzene (abbreviated as OXD-7), such as 5-(4-biphenyl Class)-3-(4-tert-butylphenyl)-4-phenyl-1,2,4-triazole (abbreviated as TAZ) and 5-(4-biphenyl)-3-(4-tert Triazole derivatives such as butylphenyl)-4-(4-ethylphenyl)-1,2,4-triazole (abbreviated as p-EtTAZ), and triazole derivatives such as angiophenanthroline (abbreviated as BPhen ) And phenanthroline derivatives such as cuprous reagent (abbreviated as BCP).

Those examples that are effectively used as receptors and are to be evaporated typically include such as TCNQ, TCE, DDQ, benzoquinone, 2-6-naphthoquinone, p-fluoranes, tetrachlorodiphenol benzoquinone, Those used as Lewis acids, such as nickel diphenyl oxime sugar. Examples of those effectively used as donors and to be evaporated, in addition to organic compounds such as TTF, TTT, methylphenothiazine, and N-isopropyl oxazole, also representatively include alkalis with strong donor properties. Metals and alkaline earth metals are used as those used as Lewisites.

As an example, an organic conductive film represented by a conductive polymer is waiting to be deposited by a wet process that usually includes a wet coating of a solution of a high polymer having a π-conjugated system mixed with an acceptor or a donor body. If the film-forming properties are good, low-molecular organic compounds can be used instead of high polymers. In this case, the organic conductive film mixed with the acceptor is preferably also used as the hole injection layer, and the organic conductive film mixed with the donor is preferably used as the electron injection layer.

In addition to practical materials such as polydihydroxythiophene ethylene (abbreviated as PEDOT), polyaniline (abbreviated as PAni), polypyrazine, and the like, high polymers with π-conjugated systems also include, for example, polyphenylene derivatives , Polythiophene derivatives, and polyvinylidene-p-benzene derivatives.

These above can be used as acceptors or donors. However, using receptors for water-soluble polymers such as polystyrene sulfonic acid (PSS), it is possible to perform wet coating in a water-solvent system. It is known that PEDOT/PSS and PAni/PSS are particularly suitable for hole injection layers.

At the same time, the tapered insulating dam is explained for the example of Figs. 1-3. But when the insulating dam takes other forms, similar or greater effects can be obtained. Figures 14A-C show some typical drawings in which the tapered insulating dam of Figure 1C is made in another form.

FIG. 14A is a case where the insulating dam 103 is made into a curved shape at its end, and has a radius of curvature R1 at the inner side of the insulating dam 103. In this case, as shown in FIG. 14A, since the insulating dam exhibits an arc shape at its end, it is easy to form a state of T2>T1>T3. To be precise, since the thickness of T3 decreases as it approaches the top of the insulating dam, it plays a great role in preventing crosstalk.

FIG. 14B is a case where the insulating dam 103 is made into a curved shape at its end, with a radius of curvature R1 at the inner side of the insulating dam 103 and a radius of curvature R2 at the outer side of the insulating dam 103. In this case, as shown in FIG. 14B, since the insulating dam shows an S shape at its end, it is also easy to form a state of T2>T1>T3. In this case, since the thickness of T3 decreases as it approaches the top of the insulating dam, it has a great effect in preventing crosstalk.

The shape of the insulating dam shown in FIGS. 14A and 14B is particularly effective in the case of wet coating by a spin coating process. This is because the slowly changing end of the insulating dam during the coating process causes the liquid to spread easily and uniformly.

By the way, in the case where hydrogen atoms or molecules pre-exist in the organic conductive film 104, 204, or 304 due to hydrogen plasma or hydrogen ion doping and diffuse due to heating after the organic thin film 205 or 305 is formed, When an unpaired bond (or group of atoms) in the organic thin film 205 or 305 is caused during the advancing process, it can be paired again, thereby preventing degradation.

Fig. 4 shows a conceptual diagram of a device for manufacturing the display device shown in Figs. 2 and 3. This equipment is based on the example of the production of organic thin films by the vacuum deposition method. That is, it is composed of a transfer cabin for transferring the substrate, a throwing cabin for putting the substrate, a deposition cabin for making various thin films, and a sealed cabin for sealing. Each compartment has an evacuation device to obtain the required vacuum or a device to generate a gas atmosphere such as nitrogen. The various compartments are connected to each other by valves and the like. The transfer robot is used to transfer the substrate.

First, the substrate 401c (although pixel regions, driving circuits, interconnections, electrodes, protective films, etc. have been previously fabricated, but hereinafter simply referred to as "substrate") is placed in the loading compartment 400 from the outside. Generally, TFTs are used in the pixel area and the driving circuit area.

The substrate 401c in the loading chamber 400 is transferred to the transfer chamber 401a by the transfer robot 401b, and then to the pretreatment chamber 402. Usually, heating, O₂In the plasma treatment and other methods, the substrate 401c is pretreated in the pretreatment chamber 402. The purpose of the pretreatment is to improve the characteristics of the OLED. This is also used to make the coated surface of the substrate hydrophilic, thereby improving the wettability of the water-soluble conductive polymer while waiting to be coated as an organic conductive film.

The substrate after the pretreatment is returned to the loading compartment again to receive nitrogen purge. Then, under normal pressure (nitrogen gas environment), the substrate is transferred to the transfer chamber 420, and is reversed to the normal position in the inversion chamber 422. Then, an organic conductive film (specifically, a conductive polymer such as PEDOT/PSS) is coated in the coating chamber 421. Although the coating method includes spin coating or dip coating, the film formation here uses spraying technology. After coating, the substrate is transferred by the transfer chamber 420 to the inversion and vacuum baking chamber 423. In this cabin, inversion and vacuum baking are carried out.

In this way, the vacuum baking here is performed in an inverted state (that is, in a state where the surface of the substrate faces downward). However, it is known that the relationship T2>T1>T3 in FIGS. 1A-1C or 14A-14B can be maintained without any problem when the surface is facing downward (see Embodiment 8 later).

After the vacuum baking, the substrate is transferred to the transfer chamber 404 through the transfer chamber 401a and the dropping chamber 403. In the transfer compartment 404, a transfer robot installed therein serves to transfer the substrate to each compartment connected to the transfer compartment 404. The transfer chamber 404 is connected to a deposition chamber for making an organic layer. The respective deposition chambers 406R, 406G, and 406B are built to produce RGB color light-emitting layers in order to manufacture a full-color OLED display device. Furthermore, in order to make layers common to each color, that is, the carrier transport layer and the carrier injection layer, a deposition chamber 405 is established. These deposition chambers usually use a vacuum deposition process. In order to obtain full-color light emission, deposition can be carried out with a shadow mask for separate coating, so that each light-emitting layer used to emit RGB light is arranged in a stripe, mosaic, or delta shape. By the way, in the case where the organic conductive material is applied to the entire surface by a spin coating or dip coating process, before the organic layer is deposited, the pretreatment chamber 402 is combined with a mask.₂Plasma processing. This can remove an undesirable part of the organic conductor film (a part to be coated with a sealant or a part on the interconnection).

After the organic layer deposition is completed, the substrate is transferred to the transfer chamber 408 via the drop-in chamber 407. In the transfer compartment 408, a transfer robot installed therein serves to transfer the substrate to each compartment connected to the transfer compartment 408. The transfer chamber 408 is connected to a deposition chamber for making back electrodes or protective films. In the deposition chamber 409, the electrode metal (for example, AlLi alloy or MgAg alloy) is evaporated by a vacuum evaporation process or an EB process. In the deposition chamber 411, a sputtering process or a chemical vapor deposition (CVD) process is usually used to deposit a transparent conductive film (such as ITO or IZO) required for light emission on the top surface of the substrate. In the deposition chamber 412, a passivation film (such as a SiN or SiOx film) for surface protection is usually deposited by sputtering or CVD.

The substrate on which the film is completed is transferred to the transfer chamber 414 via the drop-in chamber 413. The transfer compartment 414 is connected to a plurality of compartments for sealing. In the transfer compartment 414, the transfer robot installed therein serves to transfer the substrate or the sealed substrate to the respective compartments connected to the transfer compartment 414.

First, a substrate for sealing needs to be prepared. To this end, a sealed glass substrate preparation chamber 415a and a sealed plastic substrate preparation chamber 418 are provided.

In the sealing glass substrate preparation chamber 415a, reverse glass is placed from the outside to perform glass sealing on the manufactured OLED. If necessary, a desiccant for OLED waterproof can be placed on the reverse glass. For example, the sheet-like desiccant can be bonded to the smoothed small area portion previously formed in the reverse glass with a double-sided tape or the like.

On the other hand, in the sealed plastic substrate preparation chamber 418, preparation is performed to plastic seal the manufactured OLED. This operation can be fully automated or partly manual by providing glass balls.

The prepared sealing glass or plastic substrate is transferred to the configuration chamber 416 to apply an adhesive (not shown) for later bonding with the substrate. This embodiment uses a UV cured adhesive. If necessary, a desiccant (not shown) for OLED waterproofing can be reserved in the configuration compartment 416 instead of during the placing of the glass in the sealing glass substrate preparation compartment 415a. For example, the sheet-shaped desiccant can be bonded to the small area portion that was previously formed on the reverse glass and is flattened with a double-sided tape or the like. This eliminates the need to dispose of desiccant in the air. This operation can be fully automated or partly manual with the help of providing balls. Especially when the sealing plastic substrate has bending and elasticity, the adhesive can be coated in a curved or straight shape.

The deposited substrate and the sealed glass or plastic substrate coated with an adhesive are transferred to the sealed chamber 417 and bonded together. During the bonding process, a suitable clamp (not shown) needs to be used to apply pressure. In the case that the sealing plastic substrate has bending and elasticity, the bonding can be completed in a straightened state. This operation can be fully automated or partly manual by means of providing balls.

Then, the substrate and the sealing substrate bonded together in the sealing chamber 417 are transferred to the UV radiation chamber 418 to be irradiated with ultraviolet rays to cure the adhesive.

The bonded substrate and the sealing substrate in the UV radiation chamber 418 can be taken out from the dropping chamber 419.

[Example 1]

This embodiment uses the display device disclosed in the present invention as an example to illustrate the passive matrix display device. Figure 5A shows its top view. 5B shows a cross-sectional view along the line P-P' in FIG. 5A.

In FIG. 5A, reference numeral 501 denotes a substrate, and plastic materials and glass are used to make the substrate. Sheet or film polyimine, polyamine, acrylic resin, epoxy resin, PES (polyether agglomerate), PC (polycarbonate), PET (polyethylene terephthalate), or PEN (polyether Nitrile) can be used as this plastic material.

Reference numeral 502 denotes a scanning line (anode) composed of a conductive oxide film. The conductive oxide film used in this embodiment was obtained by using indium tin oxide (ITO) which is transparent to visible light. Reference numeral 506 denotes a data line (cathode) including a metal film. Use CaF₂\Al electrode, the data line is made into a striped pattern. Reference number 503 denotes an insulating dam composed of acrylic resin. The scan line 502 and the data line 506 are respectively made into strips. The two graphics are orthogonal to each other. Although not shown in FIG. 5A, the conductive polymer (PEDOT/PSS) 504 and the organic thin film 505 are sandwiched between the scan line 502 and the data line 506. The cross member 507 serves as a pixel.

The scan line 502 and the data line 506 are connected to an external driving circuit through the TAB tape 508. Reference numeral 509 denotes a set of wiring, which is a large number of scanning lines 502. 510 denotes a set of wiring, which is a large number of connection wirings 511 connected to the data line 506. Although not shown, TCP obtained by mounting the IC on the TAB tape can be connected instead of the TAB tape 508.

In FIG. 5B, 512 denotes a sealing member, and 513 denotes a covering member bonded to the substrate 501 with the sealing member 512. A photocurable resin can be used for the sealing member 512. The sealing element 512 is preferably made of a material that is not easy to outgas and absorb moisture. The material of the covering element is preferably the same as that of the substrate 501, and may be made of glass (including quartz glass) or plastic. Glass is used here.

The light-emitting device of the present invention composed of the above-mentioned elements can be manufactured by a very simple process because the pixel member is composed of the scan line 502, the data line 506, the insulating bank 503, the conductive polymer 504, and the organic thin film 505.

The polarizer may be provided on the display screen of the display device shown in this embodiment (on which an image is displayed). The function of the polarizer is to minimize the reflection of light entering the display screen from the outside, so as to prevent the observer from being reflected on the display screen. Usually circular polarizers are used. However, the display device preferably has a configuration that makes it difficult to cause internal reflection by adjusting the refractive index so as to prevent the light radiated from the organic film from returning to the inside by the reflection of the polarizing plate.

[Example 2]

In this embodiment, a display device including the organic light emitting device disclosed in the present invention will be explained. Fig. 6 shows an active matrix type display device. Figure 6A shows a top view. Fig. 6B shows a cross-sectional view taken along the line P-P' in Fig. 6A.

Note that although thin film transistors (hereinafter referred to as TFTs) are used as the active device in this embodiment, MOS transistors may also be used. In addition, although a top-gate TFT (actually a planar TFT) is exemplified as a TFT, a bottom-gate TFT (typically an anti-interleaved TFT) can also be used.

6A and 6B, reference numeral 601 denotes a substrate. In order to observe the light passing through the substrate in the display device, the substrate must be transparent to visible light. In fact, glass substrates, quartz substrates, crystallized glass substrates, or plastic substrates (including plastic films) can be used. Note that the substrate 601 includes an insulating film provided on the surface thereof.

The pixel member 621 and the driving circuit 622 are provided on the substrate 601. The pixel member 621 is first explained below.

The pixel member 621 is an area where image display is performed. A plurality of pixels are fabricated on the substrate, and each pixel is equipped with a TFT 611 (hereinafter referred to as a current control TFT) for controlling the current flowing in the organic light-emitting device, a pixel electrode (anode) 602, a conductive polymer film 604, and an organic thin film 605 , And cathode 606. Each pixel is surrounded by an insulating bank 603. In addition, reference numeral 612 denotes a TFT (hereinafter referred to as a switching TFT) used to control the voltage applied to the gate of the current control TFT.

Both n-channel type TFT and p-channel type TFT can be used for the current control TFT 611. However, it is preferable to use a p-channel type TFT here because, as shown in FIGS. 6A and 6B, in a case where the current control TFT is connected to the anode of the organic light emitting device, the p-channel type TFT is excellent in suppressing electric power consumption. Note, however, that the switching TFT may be an n-channel TFT or a p-channel TFT.

It should be noted that the drain of the current control TFT 611 is electrically connected to the pixel electrode 602. In this embodiment, since a conductive material with a power function of 4.5-5.5 eV is used to make the pixel electrode 602, the pixel electrode 602 is used as the anode of the organic light-emitting device. The pixel electrode 602 is generally made of a material that is transparent to light, such as indium oxide, tin oxide, zinc oxide, or a compound thereof (for example, ITO). The conductive polymer 604 and the organic thin film 605 are fabricated on the pixel electrode 602.

Furthermore, the cathode 606 is formed on the organic thin film 605. It is advisable to use a conductive material with a power function of 2.5-3.5 eV to make the cathode 606. The cathode 606 is usually made of a conductive film containing an alkali metal element or a rare metal element or a conductive film containing aluminum, and a conductive film of aluminum or silver is laminated on the above-mentioned conductive film.

The layer containing the cathode 606 is covered by a protective film 607. The protective film 607 is made to prevent oxygen and water from penetrating into the organic light emitting device. Silicon nitride, silicon oxynitride, aluminum oxide, tantalum oxide, or carbon (typically diamond-like carbon) can be used as the material for forming the protective film 607. Especially in the case where diamond-like carbon is used for the protective film 607, hydrogen atoms are contained in the protective film 607. As described above, the diffusion of hydrogen atoms into the organic film due to heating is beneficial to prevent the degradation of the organic film by stopping the dangling bonds (or groups of atoms) generated in the organic film during the advancement process.

Next, the driving circuit 622 will be explained. The driving circuit 622 is an area that controls the timing of the signals (gate signal and data signal) sent to the pixel member 621, and is equipped with a shift register, a buffer, a latch, an analog switch (transfer gate), or a level shift Device. In FIGS. 6A and 6B, a CMOS circuit composed of an n-channel TFT 613 and a p-channel TFT 614 is shown as the basic components of these circuits.

The circuit structure of the shift register, buffer, latch, analog switch (transmission gate), or level shifter can be designed to have a generally well-known structure. In addition, although the pixel member 621 and the driving circuit 622 are provided on the same substrate in FIGS. 6A and 6B, it is also possible to electrically connect the IC and the LSI without providing the driving circuit 622.

Reference numeral 623 denotes a gate signal line driving circuit, and 622 denotes a data signal line driving circuit. The signal is transmitted from the TAB (Tape Automatic Bonding) tape 616 to the gate signal line driving circuit 623 and the data signal line driving circuit 622 through the input wiring 615. Although not shown, a TCP (Tape Carrier Package) obtained by mounting an IC (Integrated Circuit) to a TAB (Tape Automatic Bonding) tape may be connected instead of the TAB tape 616.

Reference numeral 608 denotes a covering member coated on the top of the display device by means of a sealing member 609 containing resin. Any material that does not allow penetration of oxygen and water can be used for the covering element 608. The covering element is composed of glass 608a with grooves and desiccant 608b. Thus, the organic light emitting device is completely sealed in the closed space 610 by the sealing element 609. The enclosed space 610 may be filled with inert gas (typically nitrogen or rare gas), resin, or inert liquid (for example, liquid fluorocarbon such as perfluoroalkane). In addition, it is effective to place the absorbent and the oxygen scavenger in the enclosed space 610.

It is shown in FIGS. 6A and 6B that the pixel electrode (anode) 602 is electrically connected to the current control TFT 611. But the display device may be configured in which the cathode is connected to the current control TFT. In this case, the same material as that used to form the cathode 606 may be used for the pixel electrode, and the same material as the material used to form the pixel electrode (anode) 602 may be used for the cathode. This situation requires the current control TFT to be an n-channel TFT.

The polarizer may be provided on the display screen of the display device shown in this embodiment (on which an image is displayed). The function of the polarizer is to minimize the reflection of light entering the display screen from the outside, so as to prevent the observer from being reflected on the display screen. Usually circular polarizers are used. However, the display device preferably has a configuration that makes it difficult to cause internal reflection by adjusting the refractive index so as to prevent the light radiated from the organic film from returning to the inside by the reflection of the polarizing plate.

[Example 3]

In this embodiment, a display device is taken as an example to explain the active matrix display device. In this embodiment, a display device whose structure is different from that shown in Embodiment 2 is shown in which light is emitted from the counter substrate of the fixed active device (hereinafter referred to as top emission). Figure 7 shows its cross-sectional view.

Note that although thin film transistors (hereinafter referred to as TFTs) are used as the active device in this embodiment, MOS transistors may also be used. In addition, although a top gate type TFT (actually a planar TFT) is exemplified as a TFT, a bottom gate type TFT (typically an inverted trapezoidal TFT) can also be used.

In this embodiment, except for the first electrode, the second electrode, the protective film, and the covering element, it may have the same structure as that shown in Embodiment 2.

Since the first electrode 602 connected to the current control TFT 611 is used as an anode in this embodiment, it is preferable to use a conductive material with a large power function for the electrode. Typical examples of such conductive materials include metals such as nickel, palladium, tungsten, gold, and silver. In this embodiment, the first electrode 602 is preferably opaque to light, and is preferably composed of a highly reflective material.

Since the top emission structure is exemplified here, the second electrode 606 used in the display device is transparent to light. Therefore, when metal is used for the second electrode 606, the second electrode 606 is preferably made as an ultra-thin film with a thickness of 20 nm.

The protective film 607 is made to protect the organic light emitting device from oxygen and water. In this embodiment, any material can be used for the protective film as long as it is transparent to light.

Reference numeral 608 denotes a covering member bonded by a sealing member 609 containing resin. As long as the material does not allow penetration of oxygen and water and is transparent to light, any material can be used for the covering element 609. In this embodiment, glass is used to cover the element. The enclosed space 610 may be filled with inert gas (typically nitrogen or rare gas), resin, or inert liquid (for example, liquid fluorocarbon such as perfluoroalkane). In addition, it is effective to place the absorbent and the oxygen scavenger in the enclosed space 610.

It is shown in FIG. 7 that the first electrode (anode) 602 is electrically connected to the current control TFT 611. But the display device may be configured in which the cathode is connected to the current control TFT. In this case, the same material as that used to form the cathode may be used for the first electrode, and the same material as the material used to form the anode may be used for the second electrode. This situation requires the current control TFT to be an n-channel TFT.

[Example 4]

This embodiment shows the display device shown in Embodiment 2 or 3 that is driven based on digital time gray scale display.

FIG. 8A shows the circuit structure of a pixel using an organic light-emitting device. Tr represents a transistor, and Cs represents a storage capacitor. In the circuit structure of FIG. 8A, the source line is connected to the source side of the transistor Tr1, and the gate line is connected to the gate side of the transistor Tr1. The power supply line is connected to the source side of the storage capacitor Cs and the transistor Tr2. Since the anode of the organic light emitting device of the present invention is connected to the drain side of the transistor Tr2, the cathode is made on the opposite side of the transistor Tr2 on the organic light emitting device.

In this circuit, when the gate line is selected, current flows from the source line to Tr1, and the voltage corresponding to this signal is accumulated in Cs. Then by the gate-source voltage of Tr2 (V_gs) The controlled current flows into Tr2 and the organic light-emitting device.

After Tr1 is selected, Tr1 is turned off to maintain the voltage of Cs (V_gs). Therefore, the current is dependent on V_gsThe number continues to flow.

Fig. 8B shows a timing chart for driving this circuit according to a digital time gray scale display. In digital time grayscale display, a frame is divided into multiple sub-frames. Fig. 8B shows 6-bit gray scale, in which a frame is divided into 6 sub-frames. SF1-SF6 represent the frame, and TA represents the write cycle. In this case, the ratio of the light-emitting period of each sub-frame is 32:16:8:4:2:1.

FIG. 8C schematically shows the driving circuit of the TFT substrate in this embodiment. In the circuit structure of FIG. 8C, the power supply line and the cathode shown in FIG. 8A are connected to the pixel member, in which each pixel is composed of the organic light emitting device of the present invention. The shift resistor is connected to the pixel member via the latch 1 and the latch 2 in this order. The digital signal is input to the latch 1, and the latch pulse is input to the latch 2, so as to transmit the image data to the pixel member.

The gate driver and the source driver are provided on the same substrate. In this embodiment, the pixel circuit and the driver are designed to be digitally driven. Therefore, the characteristic fluctuation of the TFT does not affect the device, and the device can display a uniform image.

[Example 5]

The display device of the present invention described in the above embodiments has the advantages of low power consumption and long life. Therefore, electrical appliances including these display devices as their display parts can operate with lower power consumption than conventional electrical appliances and have a long life. Especially for electrical appliances such as portable devices that use batteries as power sources, these advantages are very useful because low power consumption directly leads to convenience (long battery life).

This display device is self-luminous, and therefore does not require the backlight used in liquid crystal displays. The device has an organic thin film with a thickness of less than 1 micron. Therefore, the display device can be made thin and light. Therefore, the electric appliance including the display device as its display part is thinner and lighter than the conventional electric appliance. This also directly leads to convenience (lighter and more compact to carry), and is particularly useful for portable devices and other similar appliances. Moreover, in terms of transportation (can be transported in large quantities) and installation (saving space), thin (not large) is undoubtedly useful for all electrical appliances.

As a self-luminous device, this display device is characterized by its sharp visibility in bright places and a wider viewing angle than a liquid crystal display device. Therefore, an electrical appliance including this display device as its display part has the advantage of easy observation and display.

More specifically, in addition to the advantages of conventional organic light-emitting devices, that is, thinness/lightness and high visibility, the electrical appliances using the display device of the present invention also have the new features of low power consumption and long life, so they are very useful. .

This embodiment exemplifies an electrical appliance including the display device of the present invention as a display part. Specific examples are shown in Figs. 9 and 10. The organic light-emitting device included in the electrical appliance of this embodiment may be any element disclosed in the present invention. The light-emitting device included in the electrical appliance of this embodiment may have any structure shown in FIGS. 2, 3, and 5-8.

Fig. 9A shows a display using an organic light-emitting device. The display includes a case 901a, a supporting base 902a, and a display part 903a. Using the light-emitting device of the present invention as the display portion 903a, the display can be thin, light, and inexpensive. Therefore, transportation is simplified, the table top occupied is small, and the life span is long.

FIG. 9B shows a video camera including a main body 901b, a display portion 902b, a sound input portion 903b, an operation switch 904b, a battery 905b, and an image receiving portion 906b. Using the light-emitting device of the present invention as the display portion 902b, the power consumption of the video camera is smaller and the weight is lighter. Therefore, battery consumption is reduced and it is easier to carry.

FIG. 9C shows a digital camera, which includes a main body 901c, a display portion 902c, a finder frame 903c, and an operation switch 904c. Using the light-emitting device of the present invention as the display portion 902c, the power consumption of the digital camera is smaller and the weight is lighter. Therefore, battery consumption is reduced and it is easier to carry.

Figure 9D shows a video player equipped with a recording medium. This device includes a main body 901d, a recording medium (such as a CD, LD, or DVD) 902d, an operation switch 903d, a display portion A 904d, and a display portion B 905d. The display part A 904d mainly displays image information, and the display part B 905d mainly displays text information. Using the light-emitting device of the present invention as the display part A 904d and the display part B 905d, the power consumption of the video player is smaller, the weight is lighter, and the price is low. The video player equipped with a recording medium may be a CD player, a game machine, and the like.

FIG. 9E shows a mobile computer, which includes a main body 901e, a display portion 902e, an image receiving portion 903e, an operation switch 904e, and a memory socket 905e. Using the light-emitting device of the present invention as the display portion 902e, the mobile computer has lower power consumption and lighter weight. Therefore, battery consumption is reduced and it is easier to carry. This mobile computer has a recording medium integrated with fast memory and non-volatile memory, which can record and play information.

FIG. 9F shows a personal computer, which includes a main body 901f, a frame 902f, a display portion 903f, and a keyboard 904f. By using the light-emitting device of the present invention as the display portion 903f, the personal computer has lower power consumption, is thinner and lighter in weight. When used as a mobile computer, that is, when it needs to be carried, low power consumption and light weight are of great benefit.

Note that the above-mentioned various electrical appliances display information transmitted through electronic communication lines such as the Internet or radio communications such as radio waves in many cases, especially animation information with increased frequency. Since the organic light-emitting device has a very fast response speed, the above-mentioned electrical appliance is very suitable for this kind of animation display.

FIG. 10A shows a mobile phone which includes a main body 1001a, a sound output part 1002a, a sound input part 1003a, a display part 1004a, an operation switch 1005a, and an antenna 1006a. Using the light-emitting device of the present invention as the display part 1004a, the power consumption of the mobile phone is smaller, thinner and lighter. Therefore, the main body becomes compact, battery consumption is reduced, and it is easier to carry.

FIG. 10B is a sound playback device (specifically, a car audio system), which includes a main body 1001b, a display portion 1002b, and operation switches 1003b and 1004b. Using the light-emitting device of the present invention as the display part 1002b, the power consumption of the sound playback device is smaller and the weight is lighter. Although a car audio system is used as an example in this embodiment, it may be a home audio system.

In the electrical appliance shown in Figures 9-10, it is effective to further build an optical sensor to provide a means to detect the brightness of the use environment, thereby providing a function to modulate the brightness of the emitted light according to the use environment. of. If the user can ensure that the brightness in the contrast ratio compared to the brightness of the use environment is 100-150, the image or text can be recognized without difficulty. That is, when the environment is bright, the brightness of the image is increased so that the image can be easily seen, and when the environment is dim, the brightness of the image is suppressed, thereby reducing power consumption.

[Example 6]

The conductive polymer can be made into strips by a dispenser or an inkjet method instead of being applied to the entire surface by a spin coating process. FIG. 11 shows a method of making a conductive polymer 1106 on the pixel area 1102 of the substrate 1101 on which the data driving circuit 1104 is made by the inkjet method. The pixel area 1102 has strip-shaped banks 1105 so that a conductive polymer 1106 is formed between the banks. The dam 1105 is made so that the adjacent organic compound layers do not mix with each other in the process of forming the organic compound layer by the inkjet method.

The conductive polymer 1106 is formed by ejecting a constituent material containing a conductive polymer by the inkjet head 1107. The constituent materials are continuously ejected by the inkjet head to form a linear pattern.

FIG. 12A shows that the insulating bank 103a is provided in the form of surrounding the pixel 110a so as to form the first electrode 102a and the pixel 110a in a strip shape (vertical in the figure) on the substrate. FIG. 12B shows that the insulating bank 103b is raised to surround the pixel 110b so as to form the island-shaped first electrode 102b and the pixel 110b on the substrate. In either case, the cross-section along the line AA' in the figure is shown in Fig. 12C. That is, the conductive polymer 104 can be made in a separated form between the dams, instead of being formed on the dam 103. On the conductive polymer layer, a light-emitting layer or an electron injection layer/electron transport layer can be made of low-molecular compound materials.

In this case, under the influence of the insulating dam 103, the conductive polymer 104 has a thickness form of T2>T1>T3. Therefore, the T3 part has an increased lateral resistance, thereby preventing crosstalk. Moreover, since the T2 portion has an increased thickness, it is possible to weaken the intensity of the electric field around the pixel, thereby preventing degradation of the organic light-emitting element around the pixel.

[Example 7]

This embodiment shows an example of manufacturing an active matrix display device.

First, a plurality of TFTs (including a switching TFT and a current control TFT), a holding capacitor, a first electrode (anode) connected to the current control TFT, and a bank covering the end of the first electrode are fabricated on an insulating surface. The material of the first electrode can be selected from Ti, TiN, TiSi_xN_y, Ni, W, WSi_x, WN_x, WSi_xN_y, NbN, Mo, Cr, Pt, or Ti, Si, Ni, W, Nb, Cr, Zn, Sn, In, Mo alloys or compounds. In addition, the first electrode may be a thin film or a laminated film based on these materials with a total film thickness of 100-800 nm. In order to provide better coverage, the dam is made to have a curved surface with curvature at its upper and lower ends. For example, in the case where positive photosensitive acrylic is used as the dam material, it is better to provide only the insulator 1114 having a curved surface with a radius of curvature (0.2-3 microns) at the upper end thereof. For the dam, the negative type can be used to make it insoluble in the corrosive by means of photosensitive light, or the positive type can be used to make it dissolve in the corrosive by light.

Then, using a coating method, a hole injection layer is formed on the surface of the first electrode in the area not covered by the dam. For example, using a spin coating method, a polydihydroxythiophene/polystyrene sulfonic acid solution (PEDOT/PSS) used as a hole injection layer is applied to the entire surface, and then baked. After the hole injection layer is formed by the coating method, it is best to perform vacuum heating (at 100-200° C.) immediately before the film formation caused by the deposition process. For example, after washing the surface of the first electrode (anode) with a sponge, a polydihydroxythiophene/polystyrene sulfonic acid solution (PEDOT/PSS) is applied to the entire surface by a spin coating method to a set film thickness of 60 nm. Pre-baked at 80°C for 10 minutes, and then baked at 200°C for 1 hour. Moreover, immediately before deposition, vacuum heating (heating at 170°C for 30 minutes and cooling for 30 minutes) is performed immediately to form an organic thin film including a light-emitting layer without contact with air by a deposition process. Specifically, in the case of using an ITO film as the first electrode material in which there are concavities/convexes or fine particles on the surface, by providing PEDOT/PSS with a thickness of 30 nm or more, the influence can be reduced, and as a result, it can be Reduce point defects.

At the same time, the wettability of PEDOT/PSS coated on the ITO film is not satisfactory. Therefore, after first applying the PEDOT/PSS solution with a spin coating process, it is immediately washed with pure water to improve the wettability. The PEDOT/PSS solution was applied for the second time by the spin-coating process, and then baked to better form a uniform film. By the way, after the first application, washing with pure water provides the effect of improving the surface quality and removing fine particles.

In the case of the PEDOT/PSS film made by the spin coating process, the obtained film is on the entire surface. It is preferable to selectively remove the thin film in the end surface of the substrate and the peripheral edge area, the terminal area, and the connection area between the cathode and the lower interconnection. It is best to use oxygen ablation and other methods to remove.

Next, a second electrode (cathode) is formed on the organic thin film. The second electrode can be made of materials with a small power function (Al, Ag, Li, Ca or their alloys MgAg, MgIn, AlLi, CaF₂, CaN). It is better to evaporate the second electrode by a resistance heating process that causes less damage to the TFT.

FIG. 13A is a TEM photograph of the device after the second electrode is fabricated, which is observed by cutting the device. FIG. 13B is a typical diagram corresponding to FIG. 13A. In FIG. 13A, PEDOT/PSS is fabricated on the first electrode with a thickness of about 90 nm.

This embodiment forms a curved surface with curvature at the upper and lower ends of the dam. The feature provided is that even if the spin coating process is used, the thickness of the thin film between the gentle sidewall of the dam and the first electrode is also made smaller, and the structure is preferably made such that the conductive polymer as the hole injection layer does not exist in the dam. Upper part.

As shown in FIG. 13A, although PEDOT/PSS as a hole injection layer exists on the gentle sidewall of the dam with a small thickness, it has not been confirmed to be on the upper part of the dam. By providing the structure of FIG. 13A, the occurrence of crosstalk can be effectively suppressed.

This embodiment can be freely combined with any of the embodiments 1-6.

[Example 8]

In the case of manufacturing the organic light-emitting device of the present invention with the equipment shown in FIG. 4, in the baking process after coating the organic conductive material such as conductive polymer, the state of baking is that the coated surface is placed underneath, that is, the surface Face down. In this example, experiments were conducted to confirm that the form shown in Example 7 can be obtained by using this baking process.

First, spin coating technology is used to apply PEDOT/PSS to a substrate with an insulating dam having the same shape as the structure in FIG. 13. Then, baking was performed at 200°C with the coated surface facing down. The shape was observed by the cross-sectional TEM method, and its state is shown in Figure 15. 1501 is ITO, and 1502 is the PEDOT/PSS layer. The slightly whiter layer 1503 is a protective layer (carbon layer).

As shown in Fig. 15, it was confirmed that even when the organic conductive film was baked after wet coating in the face-down position, a shape very similar to Fig. 13 could be obtained. Therefore, regardless of the position of the substrate during the baking process, it can be formed into a shape that is a characteristic of the present invention.

[Example 9]

This embodiment shows an example of a light-emitting device in a top emission structure. Fig. 16 is a schematic diagram thereof.

Fig. 16A is a plan view showing the light emitting device. Fig. 16B is a cross-sectional view taken along the line AA' in Fig. 16A. Reference number 1601 indicates a source signal line driver circuit at the dotted line, reference number 1602 is a pixel area, and reference number 1603 is a gate signal line driver circuit. Reference number 1604 is a transparent sealing substrate, and reference number 1605 is a first sealing material. The transparent second sealing material 1607 is filled in the interior surrounded by the first sealing material 1605. The first sealing material 1605 includes a spacer material to maintain a gap between the substrates.

Reference number 1608 is an interconnection for transmitting signals to be input to the source signal line driver circuit 1601 and the gate signal line driver circuit 1603. It is used as an external input terminal to receive video or clock signals from FPC (flexible printed circuit) 1609. Note that although only the FPC is shown here, the FPC can also be fixed to the printed circuit board (PWB).

Next, the cross-sectional structure will be explained using FIG. 16B. Although the driving circuit and the pixel area are fabricated on the substrate 1610, the source signal line driving circuit and the pixel 1602 as the driving circuit are shown here.

The source signal line driver circuit 1601 is composed of a CMOS circuit composed of an n-channel TFT 1623 and a p-channel TFT 1624. The TFT forming the driving circuit may be composed of a well-known CMOS circuit, PMOS circuit, or NMOS. Although this embodiment shows a driver integrated drive circuit on the substrate, this structure is not necessarily required, that is, the drive circuit can be fabricated externally instead of on the substrate.

The pixel area 1602 is composed of a plurality of pixels including a switching TFT 1611, a current control TFT 1612, and a first electrode (anode) 1613 electrically connected to its drain. The current control TFT 1612 may be an n-channel TFT or a p-channel TFT. But when connected to the anode, it is best to use a p-channel TFT. At the same time, it is better to appropriately provide a holding capacitor (not shown). It should be noted that what is shown here is an example of a cross-sectional structure of one of a large number of arrayed pixels, in which two TFTs are used on one pixel. However, 3 or more TFTs can also be used appropriately.

Since the first electrode 1613 is structurally directly connected to the drain of the TFT, the layer under the first electrode 1613 is preferably composed of a silicon material capable of forming an ohmic contact with the drain, and is in contact with a layer containing an organic compound The uppermost layer is composed of materials with a large power function. For example, in the case of providing a three-layer structure having a titanium nitride film, an aluminum base film, and a titanium nitride film, the interconnection has favorable low resistance of ohmic contact, and serves as an anode. Meanwhile, the first electrode 1613 can be made as a single layer of a titanium nitride film, a chromium film, a tungsten film, a Zn film, or a Pt film, or three or more layers can be used.

Insulating dams (also called dams or barrier walls) 1614 are formed at both ends of the first electrode (anode) 1613. The insulating dam 1614 may be composed of an insulator containing organic resin or silicon. Here, an insulating dam in the shape of FIG. 16 is made of a positive photosensitive acrylic resin as the insulating dam 1614.

In order to achieve good coverage and uniform application of the organic conductive material, a curved surface with curvature is formed at the upper or lower end of the insulating dam 1614. For example, in the case of using positive photosensitive acrylic as the material of the insulating dam 1614, it is better to provide a curved surface with a radius of curvature of 0.2-3 micrometers only at the upper end of the insulating dam 1614. The insulating dam 1614 can be made of a negative type material, which is insoluble in the corrosive agent by means of photosensitive light, or a positive type material, which is dissolved in the corrosive agent by means of light.

At the same time, the insulating bank 1614 may be covered with a protective film aluminum nitride film, aluminum oxynitride film, carbon-based film, or silicon nitride film.

Here, the organic conductive film 1630 is formed on the first electrode (anode) 1613 and the insulating bank 1614. Although this embodiment shows an example in which the conductive polymer is coated by a spin coating process, another wet method may also be used. Alternatively, a dry method can be used to simultaneously evaporate the organic material and the acceptor or donor body. It should be pointed out that in the case of spin-coating using water-solvent-based materials such as PEDOT/PSS as conductive polymers, it is effective to apply a method such as UV ozone treatment or Ozone treatment on the coated surface in advance.₂Hydrophilic treatment such as plasma treatment followed by spin coating.

In this embodiment, since the organic conductive film 1630 is made by a spin coating process, it is coated on the entire substrate surface immediately after coating. Therefore, it is preferable to selectively remove the organic conductive film 1630 in the end surface of the substrate and the peripheral edge region, the terminal, and the region between the second electrode 1616 and the interconnection 1608. Best use O₂Ablation or laser ablation method to remove.

The organic thin film 1615 is selectively formed on the organic conductive film 1630 by a deposition process using a deposition mask or an inkjet process. Incidentally, the organic thin film 1615 in this embodiment can be assumed to be a thin film exhibiting white light emission.

Furthermore, the second electrode (cathode) 1616 is formed on the organic thin film 1615. This cathode can use materials with a small power function (Al, Ag, Li, Ca or their alloys MgAg, MgIn, AlLi, CaF₂, CaN). Here, in order to transmit the emitted light, the second electrode (cathode) 1616 uses a thinned metal thin film and a transparent conductive film (ITO (alloy of indium oxide and tin oxide), an alloy of indium oxide and zinc oxide (In₂O₃-ZnO), zinc oxide (ZnO) and the like). In this way, the organic light emitting element 1618 is composed of the first electrode (anode) 1613, the organic conductive film 1630, the organic thin film 1615, and the second electrode (cathode) 1616. Since the organic light-emitting element 1618 is made to emit white light as an example, it can be fully realized by providing a color filter having a color layer 1631 and a shielding layer (BM) 1632 (the coating layer is not shown here for simplification). Color display.

At the same time, in the case of selectively producing layers each containing an organic compound that obtains R, G, and B light emission, a full-color display can be obtained without using a color filter.

A transparent protective layer 1617 is made to seal the organic light emitting element 1618. The transparent protective layer 1617 preferably adopts an insulating film based on silicon nitride or silicon oxynitride obtained by a sputtering process (DC or RC method) or a PCVD process, or one of carbon (diamond-like carbon DLC film, carbon nitride CN film). Type) film, or a combination of layers. In the case where a silicon target is used for production in a gas environment containing nitrogen and argon, it is possible to obtain a silicon nitride film that has a strong barrier to impurities such as water or alkali metals. Otherwise, a silicon nitride target can be used. Deposition equipment can be used to make a transparent protective layer with remote plasma. In order to allow the emitted light to pass through the transparent protective layer, the film thickness of the transparent protective layer is preferably made to be as small as possible.

In order to seal the organic light emitting element 1618, the first sealing material 1605 and the second sealing material 1607 are used, and the sealing substrate 1604 is bonded in an inert gas. The first sealing material 1605 and the second sealing material 1607 are preferably made of epoxy resin. The first sealing material 1605 and the second sealing material 1607 are preferably materials that penetrate as little moisture or oxygen as possible.

In addition to glass or quartz, FRP plastic (glass fiber reinforced plastic), PVF (polyvinyl fluoride), Mylar, polyester, or acrylic can be used as the material of the sealing substrate 1604 in this embodiment. At the same time, after the first sealing material 1605 and the second sealing material 1607 are used to bond the sealing substrate 1604, a third sealing material may be used to cover the side surface (exposed surface) for further sealing.

As described above, by sealing the organic light-emitting element in the first sealing material 1605 and the second sealing material 1607, the organic light-emitting element can be completely isolated from the outside. This makes it possible to prevent intrusion from the outside of the substrate, such as moisture or oxygen, which accelerates the degradation of the organic compound layer. Thus, a reliable light-emitting device can be obtained.

Incidentally, in the case where a transparent conductive film is used for the first electrode 1613, it is possible to manufacture a light emitting device of a double-sided emission type.

By implementing the above-mentioned present invention, a conductive buffer layer using a polymer can be applied to a display device in which a matrix of organic light-emitting elements are arranged into pixels without causing crosstalk. Therefore, it is possible to provide a display device with low driving voltage, excellent reliability and heat resistance, and few short-circuit defects.

<p>101Base</p><p>102First electrode</p><p>103Insulation Levee</p><p>102aStrip-shaped first electrode</p><p>102bIsland-shaped first electrode</p><p>103aInsulating embankment</p><p>103bInsulating embankment</p><p>104Organic conductive film</p><p>110aPixel part</p><p>110bPixel part</p><p>201Base</p><p>202First electrode</p><p>203Insulating embankment</p><p>204Organic conductive film</p><p>205Organic film</p><p>206Second electrode</p><p>301Base</p><p>302First electrode</p><p>303Insulation Levee</p><p>304Organic conductive film</p><p>305Organic film</p><p>306Second electrode</p><p>307Data signal line</p><p>308Scanning signal line</p><p>309Non-linear element</p><p>310touch point</p><p>400Loading compartment</p><p>401aTransfer cabin</p><p>401bTransfer robot</p><p>401cBase</p><p>402Pretreatment chamber</p><p>420Transfer cabin</p><p>421Coating Chamber</p><p>422Inverted cabin</p><p>423Vacuum Baking Chamber</p><p>403dropping cabin</p><p>404Transfer cabin</p><p>405Deposition Chamber</p><p>406R, 406G, 406BDeposition chamber</p><p>407dropping cabin</p><p>408Transfer cabin</p><p>409Deposition Chamber</p><p>411Deposition Chamber</p><p>412Deposition Chamber</p><p>413dropping cabin</p><p>414Transfer cabin</p><p>415aSealed glass substrate preparation chamber</p><p>418Sealed plastic substrate preparation chamber</p><p>416Configuration cabin</p><p>417Sealed cabin</p><p>419dropping cabin</p><p>501Base</p><p>502Scan line (anode)</p><p>503Insulation Levee</p><p>504Conductive polymer</p><p>505Organic film</p><p>506Data line (cathode)</p><p>507Cross member</p><p>508TAB belt</p><p>509One set of wiring</p><p>510One set of wiring</p><p>511Connection wiring</p><p>512Sealing element</p><p>513covering element</p><p>601Base</p><p>602Pixel electrode (anode)</p><p>603Insulation Levee</p><p>604Conductive polymer film</p><p>605Organic film</p><p>606Cathode</p><p>621Pixel component</p><p>622Drive circuit</p><p>607Protective film</p><p>613n-channel TFT</p><p>614p-channel TFT</p><p>615Input wiring</p><p>616TAB tape (with automatic bonding)</p><p>608covering element</p><p>609Sealing element</p><p>608bDesiccant</p><p>608aGlass</p><p>610Closed space</p><p>611Current Control TFT</p><p>901aChassis</p><p>901bMain body</p><p>902bDisplay part</p><p>902aSupport base</p><p>903aDisplay part</p><p>903bVoice input section</p><p>904bOperation switch</p><p>905bBattery</p><p>906bImage receiving part</p><p>901cMain body</p><p>902cDisplay part</p><p>903cScene Frame</p><p>904cOperation switch</p><p>901dMain body</p><p>902dRecording media</p><p>903dOperation switch</p><p>904dDisplay part A</p><p>905dDisplay part B</p><p>901eMain body</p><p>902eDisplay part</p><p>903eImage receiving part</p><p>904eOperation switch</p><p>905eMemory socket</p><p>901fMain body</p><p>902fFrame</p><p>903fdisplay part</p><p>904fKeyboard</p><p>1001aMain body</p><p>1002aSound output section</p><p>1003aVoice input section</p><p>1004aDisplay part</p><p>1005aOperation switch</p><p>1006aantenna</p><p>1001bMain body</p><p>1002bDisplay part</p><p>1003bOperation switch</p><p>1004bOperation switch</p><p>1101Base</p><p>1102Pixel area</p><p>1104Data drive circuit</p><p>1105Strip dyke</p><p>1106Conductive polymer</p><p>1107Inkjet head</p><p>1114Insulator</p><p>1501ITO</p><p>1502PEDOT/PSS layer</p><p>1503Protection layer (carbon layer)</p><p>1601Source signal line drive circuit</p><p>1602pixel area</p><p>1603Gate signal line drive circuit</p><p>1604Transparent sealing substrate</p><p>1605First sealing material</p><p>1607Second sealing material</p><p>1608Interconnection</p><p>1609FPC (flexible printed circuit)</p><p>1610Base</p><p>1623n-channel TFT</p><p>1624p channel TFT</p><p>1611Switching TFT</p><p>1612Current control</p><p>1613First electrode (anode)</p><p>1614Insulation Levee</p><p>1630Organic conductive film</p><p>1615Organic film</p><p>1616Second electrode (cathode)</p><p>1618Organic light-emitting element</p><p>1631Color layer</p><p>1632Occlusion layer</p><p>1617Transparent protective layer</p>

Figures 1A-1C show the concept of the present invention; Figures 2A and 2B show the concept of the passive matrix display device of the present invention; Figures 3A and 3B show the concept of the active matrix display device of the present invention; Figure 4 shows the concept of the organic light-emitting device Manufacturing equipment; Figs. 5A and 5B show an embodiment of a passive matrix display device; Figs. 6A and 6B show an embodiment of an active matrix display device; Fig. 7 shows an embodiment of an active matrix display device; Figs. 8A-8C show a drive Example of the method; Figures 9A-9F show specific examples of electrical appliances; Figures 10A and 10B show specific examples of electrical appliances; Figure 11 shows the concept of continuous formation of conductive polymer by inkjet method; The invention uses the inkjet method to form the concept of continuous conductive polymer; Figures 13A and 13B show cross-sectional TEM photos; Figures 14A and 14B show the concept of the present invention; Figure 15 shows the cross-sectional TEM photos; and Figures 16A and 16B show the active matrix Examples of display devices.