Electron emission element, electron source, image forming device and manufacture of them

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to an electron emitting element, an electron source in which a large number of the electron emitting elements are arranged, an image forming apparatus such as a display device or an exposure apparatus configured by using the electron source, and a method for manufacturing the same.

【0002】

[Conventional technology]

Conventionally, there are roughly two types of electron emitting elements, a thermoelectron emitting element and a cold cathode electron emitting element. Cold cathode electron emitting elements include field emission type (hereinafter referred to as "FE type"), metal / insulating layer / metal type (hereinafter referred to as "MIM type"), surface conduction type electron emitting element, and the like. ..

【0003】

Examples of FE types are WP Dyke and WW Dolan, Field Emission, Advance in Electron Physics, 8,89 (1956) or CA Spindt, Physical Properties of thin-film field emission cathodes with molybdenum cones, J. Appl. The ones disclosed in Phys., 47,5248 (1976), etc. are known.

【0004】

As an example of the MIM type, those disclosed in CA Mead, Operation of Tunnel-Emission Devices, J. Appl. Phys., 32,646 (1961) and the like are known.

【0005】

Examples of surface-conducting electron-emitting elements are those disclosed in MI Elinson, Radio Eng. Electron Phys., 10, 1290 (1965) and the like.

【0006】

The surface-conduction electron emitting element utilizes a phenomenon in which electrons are emitted by passing an electric current through a thin film having a small area formed on an insulating substrate in parallel with the film surface. As this surface-conduction electron emitting element, SnO by the above-mentioned Erinson or the like₂ Using thin films, using Au thin films [G. Dittmer: Thin Solid Films, 9,317 (1972)], In₂ O₃ / SnO₂ Thin film [M. Hartwell and CG Fonstad: IEEE Trans. ED Conf., 519 (1975)], Carbon thin film [Hisashi Araki et al .: Vacuum, Vol. 26, No. 1, p. 22 (1983)) ] Etc. have been reported.

【0007】

As a typical example of these surface-conduction electron emitting devices, the device configuration of the above-mentioned M. Hartwell is schematically shown in FIG. In the figure, 1 is a substrate. Reference numeral 4 denotes a conductive film, which is made of a metal oxide thin film or the like formed in an H-shaped pattern, and an electron emitting portion 5 is formed by an energization process called energization forming, which will be described later. The element electrode spacing L in the figure is set to 0.5 to 1 mm, and W'is set to 0.1 mm.

【0008】

In these surface-conduction electron emitting elements, it is common that the conductive film 4 is preliminarily formed with an electron emitting portion 5 by an energizing process called energizing forming before emitting electrons. That is, energization forming means that a voltage is applied to both ends of the conductive film 4 to energize the conductive film 4, and the conductive film 4 is locally destroyed, deformed or altered to change its structure, resulting in electrons in an electrically high resistance state. This is a process for forming the discharge portion 5. In the electron emitting section 5, a crack is generated in a part of the conductive film 4, and electrons are emitted from the vicinity of the crack.

【0009】

Since the above-mentioned surface-conduction electron emitting element has a simple structure, it has an advantage that a large number of elements can be arranged in an array over a large area. Therefore, various applications for utilizing this feature are being studied. For example, it can be used for an image forming device such as a charged beam source and a display device.

【0010】

Conventionally, as an example of arranging a large number of surface-conducting electron emitting elements, surface conducting electron emitting elements are arranged in parallel, and both ends (both element electrodes) of the individual surface conducting electron emitting elements are wired (common wiring). An electron source in which a large number of rows are arranged (also referred to as a ladder type arrangement) in each of the rows connected in (also referred to as) is mentioned (for example, JP-A-64-31332, JP-A 1-283749, JP-A-2-257552). Issue).

【0011】

Further, particularly in a display device, a large number of surface-conduction electron emitting elements can be used as a flat plate type display device similar to a display device using a liquid crystal, and as a self-luminous display device that does not require a backlight. A display device that combines an arranged electron source and a phosphor that emits visible light by irradiating an electron beam from this electron source has been proposed (US Patent No. 5066883).

【0012】

[Problems to be Solved by the Invention]

The applicant has proposed a method for forming a conductive film as a manufacturing method advantageous for a large area in a method for manufacturing a surface-conduction electron-emitting element, regardless of a sputtering method or a thin-film deposition method using a vacuum. .. One example is a method for manufacturing an electron emitting element, in which a solution containing an organic metal is applied onto a substrate by a spinner, then patterned into a desired shape, and the organic metal is thermally decomposed to obtain a conductive film.

【0013】

Further, in Japanese Patent Application Laid-Open No. 8-171850, in the step of patterning a conductive film into a desired shape, an organic metal is used on a substrate by an ink jet method such as a bubble jet method or a piezo jet method without using a lithography method. We have proposed a manufacturing method for forming a conductive film having a desired shape by applying droplets of a solution containing the above.

【0014】

However, in the method for manufacturing an electron emitting element in which a solution containing an organic metal is applied to a substrate and the organic metal is thermally decomposed to obtain a conductive film, the surface energy of the substrate and the surface energy of the solution containing the organic metal are different. If it is not the desired one, a uniform film thickness cannot be obtained when it is applied with a spinner, and a desired shape may not be obtained when droplets are applied by an inkjet method.

【0015】

The electron emitting element using the conductive film thus formed has a problem that it affects the process of forming an electron emitting portion on the conductive film and the reproducibility of the electron emitting characteristics is poor. Further, in an electron source in which a plurality of electron emitting elements are arranged, there is a problem that the electron emitting characteristics vary. Further, even in an image forming apparatus in which an electron source and an image forming member such as a phosphor are arranged to face each other, there is a problem that variation in electron emission characteristics leads to deterioration of image quality.

【0016】

In view of the above problems, an object of the present invention is a novel configuration of an electron emitting element having good electron emitting characteristics, an electron source having high uniformity, an image forming apparatus having high uniformity and good display quality, and a good yield. The purpose is to provide those manufacturing methods that can be manufactured.

【0017】

[Means for solving problems]

The configuration of the present invention made to achieve the above object is as follows.

【0018】

That is, the first of the present invention is a step of forming a pair of element electrodes on a substrate, a step of adjusting the surface energy of the substrate, a step of applying droplets of a solution containing an organic metal, and a step of applying droplets. It has a step of thermally decomposing the material to form a conductive film and a step of forming an electron emitting portion on the conductive film by energizing between the element electrodes, and a step of adjusting the surface energy of the substrate. However, the step of measuring the surface energy state of the substrate on the spot, the step of comparing the measured surface energy of the substrate with the reference value thereof, and the step of comparing the surface energy of the substrate with the reference value, and when the surface energy of the substrate reaches the reference value, the surface energy is measured. It is a method for manufacturing an electron emitting element, which comprises a step of adjusting.

【0019】

The second aspect of the present invention lies in the electron emitting element produced by the first method of the present invention.

【0020】

The third aspect of the present invention is an electron source that emits electrons in response to an input signal, and is characterized in that a plurality of the second electron emitting elements of the present invention are arranged on a substrate. is there.

【0021】

The fourth aspect of the present invention is the method for producing the third electron source of the present invention, which comprises producing a plurality of electron emitting elements by the first method of the present invention. It is in the manufacturing method of the source.

【0022】

The fifth aspect of the present invention is a device that forms an image based on an input signal, and at least an image is formed by irradiation with the third electron source of the present invention and an electron beam emitted from the electron source. The image forming apparatus is characterized by having an image forming member to be formed.

【0023】

Further, the sixth aspect of the present invention is the method for manufacturing the fifth image forming apparatus of the present invention, wherein the electron source is produced by the fourth method of the present invention. It is in the manufacturing method.

【0024】

According to the present invention, since the step of adjusting the surface energy of the substrate includes the step of measuring the surface energy state on the spot, the surface energy can be monitored without interrupting the process, and the monitored surface energy can be monitored. Since the adjustment of the surface energy is completed when the value of is compared with the reference value and the reference value is reached, a substrate having a desired surface energy can be easily obtained in a short time.

【0025】

Further, even when the surface energy of a large number of substrates is adjusted, the variation in surface energy for each substrate is significantly reduced. Therefore, when applied with a spinner, a highly uniform film thickness can be obtained. Further, when the droplets are applied by the inkjet method, a desired shape can be obtained. Further, the surface energy of the substrate does not vary over a large number of substrates, and the yield can be improved.

【0026】

As described above, it is intended to provide an electron emitting element having good electron emitting characteristics, an electron source having high uniformity, an image forming apparatus having high uniformity and good display quality, and a manufacturing method thereof that can be manufactured with good yield. Can be done.

【0027】

BEST MODE FOR CARRYING OUT THE INVENTION

Next, a preferred embodiment of the present invention will be shown.

【0028】

FIG. 1 is a schematic view showing a configuration example of an electron emitting device of the present invention, FIG. 1 (a) is a plan view, and FIG. 1 (b) is a vertical cross-sectional view. Further, FIG. 2 is a schematic view showing another configuration example of the electron emitting device of the present invention. In FIGS. 1 and 2, 1 is a substrate, 2 and 3 are electrodes (element electrodes), 4 is a conductive film, and 5 is an electron emitting part.

【0029】

The substrate 1 is made of quartz glass, glass having a reduced impurity content such as Na, blue plate glass, blue plate glass, etc. by a sputtering method or the like.₂ It is possible to use a laminate obtained by laminating the above, ceramics such as alumina, a Si substrate, and the like.

【0030】

As the material of the opposing element electrodes 2 and 3, a general conductor material can be used, for example, metals or alloys such as Ni, Cr, Au, Mo, W, Pt, Ti, Al, Cu, Pd and the like. Pd, Ag, Au, RuO₂ , Pd-Ag and other metals or printed conductors composed of metal oxides and glass, In₂ O₃ -SnO₂ It is appropriately selected from transparent conductors such as, and semiconductor conductor materials such as polysilicon.

【0031】

The element electrode spacing L, the element electrode length W, the shape of the conductive film 4, etc. are designed in consideration of the applied form and the like. The element electrode spacing L can preferably be in the range of several hundred nm to several hundred μm, and more preferably in the range of several μm to several tens of μm in consideration of the voltage applied between the element electrodes. be able to. The element electrode length W can be in the range of several μm to several hundred μm in consideration of the resistance value of the electrode and the electron emission characteristics. The film thickness d of the element electrodes 2 and 3 can be in the range of several tens of nm to several μm.

【0032】

In addition to the configurations shown in FIGS. 1 and 2, a configuration in which the conductive film 4 and the element electrodes 2 and 3 are formed in this order on the substrate 1 can also be used. Further, depending on the manufacturing method, all of the opposing element electrodes 2 and 3 may function as electron emitting parts.

【0033】

The material constituting the conductive film 4 is appropriately selected from metals such as Pd, Pt, Ru, Ag, Au, Ti, In, Cu, Cr, Fe, Zn, Sn, Ta, W and Pb. To. These metals form organometallic compounds of conductive membrane materials.

【0034】

The film thickness of the conductive film 4 is appropriately set in consideration of step coverage to the element electrodes 2 and 3, the resistance value between the element electrodes 2 and 3, etc., but is usually in the range of several Å to several hundred nm. It is preferable that the temperature is in the range of 1 nm to 50 nm. Its resistance value is Rs of 10² Ω / to 10⁷ The value is preferably Ω / . Rs is a value that appears when the resistance R measured in the length direction of a thin film having a width of w and a length of l is set as R = Rs (l / w).

【0035】

In the present specification, the forming process will be described by taking an energization process as an example, but the forming process is not limited to this, and includes a process of causing a crack in the film to form a high resistance state. It is a thing.

【0036】

The electron emitting portion 5 is composed of high-resistance cracks formed in a part of the conductive film 4, and there may be conductive fine particles having a particle size in the range of several Å to several tens of nm inside. is there. The conductive fine particles contain some or all of the elements of the material constituting the conductive film 4. Further, the electron emitting portion 5 and the conductive film 4 in the vicinity thereof may have carbon or a carbon compound formed by the activation step described later.

【0037】

There are various methods for manufacturing the electron emitting device of the present invention, and an example thereof will be described with reference to FIG. Also in FIG. 3, the same parts as those shown in FIGS. 1 and 2 are designated by the same reference numerals.

【0038】

1) After depositing a device electrode material with a thickness of 500 Å on a cleaned blue plate glass substrate 1 by a vacuum deposition method, a sputtering method, etc., device electrodes 2 and 3 are formed using, for example, photolithography technology (Fig. 3 (Fig. 3). a)).

【0039】

2) Perform the step of initializing the surface energy of the substrate provided with the element electrodes 2 and 3. Specifically, the substrate provided with the element electrodes 2 and 3 is washed with warm water. By this step, the surface energy of the substrate becomes a hydrophilic surface.

【0040】

3) Next, the step of adjusting the surface energy of the initialized substrate is performed (Fig. 2 (b)). Specifically, the substrate initialized in the step 2) is placed in the chamber 31, dry nitrogen gas or the like is introduced to replace the inside of the chamber 31, and then the inside of the chamber 31 is appropriately diluted with nitrogen gas or the like. The organic compound gas is introduced to adjust the surface energy of the substrate.

【0041】

The organic compound gas is preferably one that adheres to the surface of the substrate and can provide a hydrophobic group such as a methyl group or an ethyl group on the substrate. , Silane coupling agent and the like can be used.

【0042】

When adjusting the surface energy of the substrate, the state of the surface energy is measured and inspected on the spot, the monitored surface energy value is compared with the reference value, and the surface energy is adjusted when the reference value is reached. finish.

【0043】

FIG. 4 is an explanatory diagram showing a process of adjusting the surface energy of the substrate, and FIG. 5 is a configuration diagram showing a device for adjusting the surface energy of the substrate. In FIG. 5, 31 is a chamber, 61 is a substrate on which element electrodes and the like are formed, 63 is a surface energy measuring means, 64 is a comparison circuit for comparing a measured value with a reference value, and 65 is a surface energy adjusting device control circuit. Is.

【0044】

The method for measuring and inspecting the state of the surface energy of the substrate may be any means capable of measuring an amount capable of directly or indirectly quantitatively expressing the state of the surface energy, for example, contact with a solution containing an organic metal. It can be carried out by measuring the angle, measuring the amount of carbon on the substrate, applying droplets of the above solution to the substrate by an inkjet method, and measuring the dot diameter of the applied droplets on the substrate. , It is possible to select a suitable method according to the surface energy adjustment method, the type of substrate, and the like.

【0045】

The area for monitoring the surface energy of the substrate is set in consideration of the area of the substrate and the monitoring method. FIG. 6 is a schematic diagram showing an installation example of the monitor area. In the installation example of FIG. 6, 10 monitor regions 181 are provided at each of the four corners of the substrate, which is the electron emitting element forming region 182. In addition, the means for the monitor may be movable or a plurality of means may be installed as needed.

【0046】

The method for adjusting the surface energy in this step is not limited to this, and the substrate is installed in the chamber, the inside of the chamber is evacuated, and then the organic compound gas is introduced into the chamber at an appropriate partial pressure. You may go in the air. In this step, the organic compound adheres to the surface of the substrate, and the surface state of the substrate changes from the water generation surface.

【0047】

The conditions for applying the organic compound gas to the substrate are set by the gas partial pressure and temperature of the organic compound. The temperature is not limited to room temperature, and an appropriate value may be selected depending on the type of gas and the type of the substrate, the desired surface energy value, and the adhesion rate of the organic compound.

【0048】

4) Next, a step of applying a solution containing an organic metal on the substrate is performed (Fig. 3 (c)). Specifically, droplets of an aqueous solution containing an organic metal are applied between the element electrodes 2 and 3 by an inkjet method such as a bubble jet method or a piezo jet method. The shape of the applied droplet 33 is determined by the surface energy of the main surface of the substrate prepared in advance in the step 3) and the surface energy of the droplet. The method of applying the aqueous solution containing an organic metal to the substrate may be a coating method using a spinner, but in this case, a patterning step is required to obtain a desired conductive film morphology.

【0049】

5) After that, the above solution applied on the substrate is thermally decomposed to form a conductive film (Fig. 3 (d)). The solution containing the organic metal applied on the substrate is thermally decomposed in an atmosphere such as the atmosphere on a firing furnace or a hot plate to form a conductive film 4 made of a metal or a metal oxide.

【0050】

6) Next, an energization process called forming is performed. When energization is applied between the element electrodes 2 and 3, an electron emitting portion 5 is formed at a portion of the conductive film 4 (FIG. 3 (e)). In the forming step, heat energy is instantaneously concentrated locally on a part of the conductive film 4, and an electron emitting part 5 having a changed structure is formed at that part.

【0051】

Figure 7 shows an example of the voltage waveform of energization forming.

【0052】

The voltage waveform is particularly preferably a pulse waveform. The methods shown in Fig. 7 (a), in which pulses with the pulse peak value as a constant voltage are continuously applied, and the method shown in Fig. 7 (b), in which pulses are applied while increasing the pulse peak value, are used. is there.

【0053】

First, the case where the pulse peak value is a constant voltage will be described with reference to FIG. 7 (a). T in Figure 7 (a)₁ And T₂ Is the pulse width and pulse interval of the voltage waveform. The peak value (peak voltage) of the triangular wave is appropriately selected according to the form of the electron emitting element. Under such conditions, for example, a voltage is applied for several seconds to several tens of minutes. The pulse waveform is not limited to a triangular wave, and a desired waveform such as a rectangular wave can be adopted.

【0054】

Next, a case where a voltage pulse is applied while increasing the pulse peak value will be described with reference to FIG. 7 (b). T in Figure 7 (b)₁ And T₂ Can be similar to that shown in FIG. 7 (a). The peak value (peak voltage) of the triangular wave can be increased by, for example, about 0.1 V step.

【0055】

The end of the energization forming process is the pulse interval T.₂ A voltage that does not locally destroy or deform the conductive film 4 is applied to the inside, and the current can be measured and detected. For example, the current flowing by applying a voltage of about 0.1V is measured, the resistance value is obtained, and when a resistance of 1 MΩ or more is shown, the energization forming is terminated.

【0056】

The electrical processing after the forming processing can be performed in a vacuum processing apparatus as shown in FIG. 8, for example. This vacuum processing device also has a function as a measurement evaluation device. Also in FIG. 8, the same parts as those shown in FIGS. 1 and 2 are designated by the same reference numerals.

【0057】

In FIG. 8, 55 is a vacuum vessel and 56 is an exhaust pump. An electron emitting element is arranged in the vacuum vessel 55. In addition, 51 is a power source for applying the element voltage Vf to the electron emitting element, 50 is a current meter for measuring the element current If flowing between the element electrodes 2 and 3, and 54 is emitted from the electron emitting part 5 of the element. The anode electrode for capturing the emission current Ie, 53 is a high-pressure power source for applying a voltage to the anode electrode 54, and 52 is a current meter for measuring the emission current Ie emitted from the electron emission unit 5. As an example, the voltage of the anode electrode 54 can be set in the range of 1 kV to 10 kV, and the distance H between the anode electrode 54 and the electron emitting element can be set in the range of 2 mm to 8 mm.

【0058】

The vacuum vessel 55 is provided with equipment necessary for measurement in a vacuum atmosphere, such as a vacuum gauge (not shown), so that measurement and evaluation can be performed in a desired vacuum atmosphere.

【0059】

The exhaust pump 56 is composed of a normal high vacuum device system including a turbo pump, a rotary pump and the like, and an ultra high vacuum device system including an ion pump and the like. The entire vacuum processing apparatus on which the electron emitting element substrate shown here is arranged can be heated by a heater (not shown).

【0060】

7) Next, the element that has been formed is subjected to a process called an activation step (Fig. 3 (f)).

【0061】

The activation step can be performed, for example, in an atmosphere containing a gas of an organic substance by repeatedly applying a pulse between the element electrodes 2 and 3 in the same manner as the energization forming. By this process, the element current If , The emission current Ie will change significantly.

【0062】

The atmosphere containing the gas of the organic substance in the activation step can be formed by utilizing the organic gas remaining in the atmosphere when the inside of the vacuum vessel is exhausted by using, for example, an oil diffusion pump or a rotary pump. It can also be obtained by introducing an appropriate organic substance gas into a vacuum once sufficiently exhausted by an ion pump or the like that does not use oil. The preferable gas pressure of the organic substance at this time differs depending on the form of the element, the shape of the vacuum vessel, the type of the organic substance, and the like, and is therefore appropriately set depending on the case. Suitable organic substances include organic acids such as alkanes, alkenes, alkyne aliphatic hydrocarbons, aromatic hydrocarbons, alcohols, aldehydes, ketones, amines, phenols, carboxylics, and sulfonic acids. Can be, specifically, methane, ethane, propane, etc. C_n H_{2n + 2}Saturated hydrocarbons represented by, ethylene, propylene, etc. C_n H_2nUnsaturated hydrocarbons represented by the composition formulas such as, benzene, toluene, methanol, ethanol, formaldehyde, acetaldehyde, acetone, methyl ethyl ketone, methyl amine, ethyl amine, phenol, formic acid, acetic acid, propionic acid and the like can be used.

【0063】

By this treatment, carbon or a carbon compound is deposited on the device from the organic substance existing in the atmosphere, and the device current If and the emission current Ie change remarkably.

【0064】

Carbon or carbon compound is, for example, graphite (including so-called HOPG, PG, GC, HOPG has almost perfect graphite crystal structure, PG has crystal grains of about 20 nm and the crystal structure is slightly disordered, GC is crystal. The grains are about 2 nm and the disorder of the crystal structure is further increased.), Amorphous carbon (refers to amorphous carbon and a mixture of amorphous carbon and the fine crystals of graphite), and the thickness thereof. Is preferably in the range of 50 nm or less, and more preferably in the range of 30 nm or less.

【0065】

The end determination of the activation step can be appropriately performed while measuring the element current If and the emission current Ie.

【0066】

8) It is preferable that the electron emitting element obtained through such a step undergoes a stabilizing step. This step is a step of exhausting the organic substance in the vacuum vessel. As the vacuum exhaust device for exhausting the vacuum container, it is preferable to use a vacuum exhaust device that does not use oil so that the oil generated from the device does not affect the characteristics of the element. Specific examples thereof include vacuum exhaust devices such as soap pumps and ion pumps.

【0067】

The partial pressure of the organic component in the vacuum vessel is 10 at the partial pressure at which the above carbon or carbon compound is hardly newly deposited.^-6Pa or less is preferable, and even 10^-10 Pa or less is particularly preferable. Further, when exhausting the inside of the vacuum vessel, it is preferable to heat the entire vacuum vessel to facilitate exhaustion of the organic substance molecules adsorbed on the inner wall of the vacuum vessel and the electron emitting element. The heating conditions at this time are 80 to 250 ° C, preferably 150 ° C or higher, and it is desirable to process for as long as possible, but the treatment is not particularly limited to these conditions, and the size and shape of the vacuum vessel and the electron emitting element It is performed under the conditions appropriately selected according to various conditions such as the configuration. The pressure inside the vacuum vessel needs to be as low as possible, 10^-5Pa or less is preferable, and even 10^-6Pa or less is particularly preferable.

【0068】

The atmosphere at the time of driving after the stabilization step is preferably maintained at the end of the stabilization treatment, but the pressure itself is not limited to this, and if the organic substances are sufficiently removed, the pressure itself is not limited to this. Can maintain sufficiently stable characteristics even if it rises a little. By adopting such a vacuum atmosphere, the deposition of new carbon or carbon compound can be suppressed, and as a result, the element current If and the emission current Ie are stabilized.

【0069】

The basic characteristics of the electron emitting device of the present invention obtained through the above steps will be described with reference to FIG.

【0070】

FIG. 9 is a diagram schematically showing the relationship between the emission current Ie and the element current If measured by using the vacuum processing apparatus shown in FIG. 8 and the element voltage Vf. In FIG. 9, since the emission current Ie is significantly smaller than the element current If, it is shown in arbitrary units. Both the vertical and horizontal axes are linear scales.

【0071】

As is clear from FIG. 9, the electron emitting element of the present invention has the following three characteristic properties with respect to the emission current Ie.

【0072】

That is, first, when an element voltage higher than a certain voltage (called a threshold voltage; Vth in FIG. 9) is applied to this device, the emission current Ie increases sharply, while when the threshold voltage Vth or less, the emission current Ie is almost the same. Not detected. That is, it is a non-linear element having a clear threshold voltage Vth with respect to the emission current Ie.

【0073】

Second, since the emission current Ie depends on the element voltage Vf for a monotonous increase, the emission current Ie can be controlled by the element voltage Vf.

【0074】

Third, the emitted charge captured by the anode electrode 54 (see FIG. 8) depends on the time the element voltage Vf is applied. That is, the amount of charge captured by the anode electrode 54 can be controlled by the time when the element voltage Vf is applied.

【0075】

As understood from the above description, the electron emitting element of the present invention can easily control the electron emitting characteristics according to the input signal. Utilizing this property, it can be applied to various fields such as an electron source composed by arranging a plurality of electron emitting elements and an image forming apparatus.

【0076】

In FIG. 9, an example in which the element current If monotonically increases with respect to the element voltage Vf (MI characteristic) is shown, but the element current If has a voltage-controlled negative resistance characteristic (VCNR characteristic) with respect to the element voltage Vf. It may be shown (not shown). These characteristics can be controlled by controlling the above-mentioned steps.

【0077】

Next, an application example of the electron emitting device of the present invention will be described below. A plurality of electron emitting elements of the present invention can be arranged on a substrate to form, for example, an electron source or an image forming apparatus.

【0078】

Various arrangements of electron emitting elements can be adopted. As an example, a large number of electron emitting elements arranged in parallel are individually connected at both ends, a large number of rows of electron emitting elements are arranged (called a row direction), and a direction orthogonal to this wiring (called a column direction). There is a ladder-shaped arrangement in which electrons from the electron emitting element are controlled and driven by a control electrode (also referred to as a grid) arranged above the electron emitting element. Separately, a plurality of electron emitting elements are arranged in a matrix in the X and Y directions, and one of the electrodes of the plurality of electron emitting elements arranged in the same row is commonly connected to the wiring in the X direction. An example is one in which the other of the electrodes of a plurality of electron emitting elements arranged in the same row is commonly connected to the wiring in the Y direction. Such a thing is a so-called simple matrix arrangement. First, the simple matrix arrangement will be described in detail below.

【0079】

The electron emitting element of the present invention has three characteristics as described above. That is, the emitted electrons from the surface-conduction electron emitting element can be controlled by the peak value and width of the pulsed voltage applied between the electrodes of the opposing elements above the threshold voltage. On the other hand, below the threshold voltage, it is hardly emitted. According to this characteristic, even when a large number of electron emitting elements are arranged, if a pulsed voltage is appropriately applied to each element, the surface-conducting electron emitting element is selected according to the input signal and the amount of electrons emitted. Can be controlled.

【0080】

Hereinafter, an electron source substrate obtained by arranging a plurality of electron emitting elements of the present invention based on this principle will be described with reference to FIG. In FIG. 10, 71 is an electron source board, 72 is an X-direction wiring, and 73 is a Y-direction wiring. 74 is an electron emitting element, and 75 is a connection.

【0081】

The m X-direction wiring 72 is composed of Dx1, Dx2, ......, Dxm, and can be composed of a conductive metal or the like formed by a vacuum deposition method, a printing method, a sputtering method, or the like. .. The wiring material, film thickness, and width are appropriately designed. The Y-direction wiring 73 is composed of n wires of Dy1, Dy2 ...... Dyn, and is formed in the same manner as the X-direction wiring 72. An interlayer insulating layer (not shown) is provided between these m X-direction wires 72 and n Y-direction wires 73, and both are electrically separated (m and n are both). Positive integer).

【0082】

The interlayer insulating layer (not shown) is a SiO formed by a vacuum deposition method, a printing method, a sputtering method, or the like.₂ Etc. For example, the film thickness is formed on the entire surface or a part of the substrate 71 on which the X-direction wiring 72 is formed so as to withstand the potential difference at the intersection of the X-direction wiring 72 and the Y-direction wiring 73. The material and manufacturing method are set as appropriate. The X-direction wiring 72 and the Y-direction wiring 73 are each drawn out as external terminals.

【0083】

The pair of element electrodes (not shown) constituting the electron emitting element 74 are electrically connected to m X-direction wires 72 and n Y-direction wires 73, respectively, by a connection 75 made of a conductive metal or the like. There is.

【0084】

The material constituting the wiring 72 and the wiring 73, the material constituting the connection 75, and the material constituting the pair of element electrodes may be the same in part or all of the constituent elements, or may be different from each other. These materials are appropriately selected from, for example, the materials of the device electrodes described above. When the material constituting the element electrode and the wiring material are the same, the wiring connected to the element electrode can also be said to be the element electrode.

【0085】

A scanning signal applying means (not shown) for applying a scanning signal for selecting a row of electron emitting elements 74 arranged in the X direction is connected to the X-direction wiring 72. On the other hand, a modulation signal generating means (not shown) for modulating each row of the electron emitting elements 74 arranged in the Y direction according to the input signal is connected to the Y-direction wiring 73. The drive voltage applied to each electron emitting element is supplied as a difference voltage between the scanning signal and the modulation signal applied to the element.

【0086】

In the above configuration, individual elements can be selected and independently driven by using simple matrix wiring.

【0087】

An image forming apparatus configured by using an electron source having such a simple matrix arrangement will be described with reference to FIGS. 11 and 12. FIG. 11 is a schematic view showing an example of a display panel of the image forming apparatus, and FIG. 12 is a schematic diagram of a fluorescent film used in the image forming apparatus of FIG.

【0088】

In FIG. 11, 71 is an electron source substrate in which a plurality of electron emitting elements are arranged, 81 is a rear plate to which an electron source substrate 71 is fixed, and 86 is a face in which a fluorescent film 84, a metal back 85, etc. are formed on the inner surface of a glass substrate 83. It is a plate. Reference numeral 82 denotes a support frame, and the rear plate 81 and the face plate 86 are connected to the support frame 82 by using frit glass or the like. Reference numeral 88 is an enclosure, for example, which is formed by sealing by firing in the air or nitrogen in a temperature range of 400 to 500 ° C. for 10 minutes or more.

【0089】

Reference numeral 74 denotes an electron emitting element as shown in FIGS. 1 and 2. Reference numerals 72 and 73 are X-direction wiring and Y-direction wiring connected to a pair of element electrodes of the surface-conduction electron emitting element.

【0090】

As described above, the outer enclosure 88 includes a face plate 86, a support frame 82, and a rear plate 81. Since the rear plate 81 is provided mainly for the purpose of reinforcing the strength of the substrate 71, if the substrate 71 itself has sufficient strength, the separate rear plate 81 can be omitted. That is, the support frame 82 may be directly sealed to the substrate 71, and the enclosure 88 may be composed of the face plate 86, the support frame 82, and the substrate 71. On the other hand, by installing a support (not shown) called a spacer between the face plate 86 and the rear plate 81, an outer enclosure 88 having sufficient strength against atmospheric pressure can be configured.

【0091】

FIG. 12 is a schematic view showing a fluorescent film. In the case of monochrome, the fluorescent film 84 can be composed of only a phosphor. In the case of a color fluorescent film, it may be composed of a black conductive material 91 called a black stripe (Fig. 12 (a)) or a black matrix (Fig. 12 (b)) and a phosphor 92 depending on the arrangement of the phosphors. it can. The purpose of providing the black stripe and the black matrix is to make the color mixing etc. inconspicuous by blackening the painted portion between each of the three primary color phosphors 92, which is necessary for color display, and to make the outside of the fluorescent film 84 inconspicuous. The purpose is to suppress a decrease in contrast due to light reflection. As the material of the black conductive material 91, in addition to the commonly used material containing graphite as a main component, a material having conductivity and less light transmission and reflection can be used.

【0092】

As a method of applying the phosphor to the glass substrate 83, a precipitation method, a printing method, or the like can be adopted regardless of monochrome or color. A metal back 85 is usually provided on the inner surface side of the fluorescent film 84. The purpose of providing the metal back is to improve the brightness by specularly reflecting the light on the inner surface side of the light emitted from the phosphor toward the face plate 86 side, and to act as an electrode for applying the electron beam acceleration voltage. For example, to protect the phosphor from damage caused by the collision of negative ions generated in the enclosure. The metal back can be produced by smoothing the inner surface of the fluorescent film (usually called "filming") after producing the fluorescent film, and then depositing Al by vacuum vapor deposition or the like.

【0093】

The face plate 86 may be provided with a transparent electrode (not shown) on the outer surface side of the fluorescent film 84 in order to further increase the conductivity of the fluorescent film 84.

【0094】

In the case of color, it is necessary to make each color phosphor and an electron emitting element correspond to each other when performing the above-mentioned sealing, and sufficient alignment is indispensable.

【0095】

The image forming apparatus shown in FIG. 11 is manufactured as follows, for example.

【0096】

Since the inside of the outer enclosure 88 is not heated appropriately, it is exhausted through an exhaust pipe (not shown) by an exhaust device that does not use oil such as an ion pump or a soap pump.^-5Sealing is performed after creating an atmosphere with a sufficiently low degree of vacuum of organic substances of about Pa. Getter treatment can also be performed to maintain the degree of vacuum of the outer enclosure 88 after sealing. This is to heat a getter (not shown) arranged at a predetermined position in the enclosure 88 by heating using resistance heating or high frequency heating immediately before or after sealing the enclosure 88. This is a process for forming a vapor-deposited film. Getters are usually mainly composed of Ba and the like, and due to the adsorption action of the vapor deposition film, for example, 1 × 10^-5It maintains a degree of vacuum equal to or higher than Pa. Here, the steps after the forming process of the electron emitting element can be appropriately set.

【0097】

Next, an example of the method for manufacturing the image forming apparatus of the present invention will be described with reference to FIG. FIG. 13 is an explanatory diagram showing a manufacturing process of the image forming apparatus of the present invention.

【0098】

Process-1 First, the substrate, element electrodes, wiring, and the like are formed. An element electrode is produced on the substrate by the same method as in step 1) in the method for manufacturing an electron emitting element. Further, the row direction wiring and the column direction wiring are formed by a screen printing method, a known photolithography technique, and a method for producing a conductor such as a sputtering method.

【0099】

Process-2 Next, the surface energy of the substrate is initialized by the same method as in step 2) in the method for manufacturing the electron emitting device.

【0100】

Process-3 Then, the surface energy of the substrate is adjusted by the same method as in step 3) in the method for manufacturing the electron emitting device. In the case of an image forming apparatus, it is necessary to provide several or more surface energy measurement points on the substrate outside the image display area in consideration of increasing the area of the substrate, and also consider the distribution thereof.

【0101】

Process-4 Next, an aqueous solution containing an organic metal is applied to the substrate by the same method as in step 4) in the method for manufacturing an electron emitting device.

【0102】

Process-5 Further, the solution containing the organic metal applied on the substrate is thermally decomposed to form a conductive film by the same method as in step 5) in the method for manufacturing an electron emitting device.

【0103】

Process-6 The substrate on which the conductive film is formed is placed in the vacuum chamber, and the inside of the vacuum chamber is sufficiently exhausted. After that, energization forming is performed by the same method as in step 6) in the method for manufacturing an electron emitting element.

【0104】

Process-7 An organic gas is introduced into the vacuum chamber, and the activation treatment is performed by the same method as in step 7) in the method for manufacturing an electron emitting device.

【0105】

Process-8 The face plate 86, the support frame 82, and the rear plate 81 are adhered to each other via a frit to form an outer enclosure 88.

【0106】

Process-9 The outer enclosure 88 is sufficiently exhausted from an exhaust pipe (not shown), and stabilization treatment is performed by the same method as in step 8) in the method for manufacturing an electron emitting element. Finally, flash the getter.

【0107】

The method for manufacturing the image forming apparatus of the present invention as described above is not limited to this, and steps-8 and subsequent steps may be performed after forming the enclosure as in the examples described later. The order and process contents are not limited to this.

【0108】

Next, a configuration example of a drive circuit for displaying a television based on an NTSC television signal on a display panel configured by using an electron source arranged in a simple matrix will be described with reference to FIG. In FIG. 14, 101 is an image display panel, 102 is a scanning circuit, 103 is a control circuit, 104 is a shift register, 105 is a line memory, 106 is a synchronous signal separation circuit, 107 is a modulation signal generator, and Vx and Va are DC voltages. It is the source.

【0109】

The display panel 101 is connected to an external electric circuit via terminals Dox1 to Doxm, terminals Doy1 to Doyn, and a high-voltage terminal 87. Terminals Dox1 to Doxm are used to sequentially drive an electron source provided in the display panel 101, that is, a group of electron emitting elements matrix-wired in a matrix of m rows and n columns, one row (n elements) at a time. A scanning signal is applied. A modulation signal for controlling the output electron beam of each element of the electron emitting element in one line selected by the scanning signal is applied to the terminals Doy1 to Doyn. A DC voltage of, for example, 10 kV is supplied to the high-voltage terminal 87 from the DC voltage source Va, because the electron beam emitted from the electron emitting element is provided with sufficient energy to excite the phosphor. Acceleration voltage.

【0110】

The scanning circuit 102 will be described. The circuit is provided with m switching elements (schematically shown by S1 to Sm in the figure) inside. Each switching element selects either the output voltage of the DC voltage power supply Vx or 0 [V] (ground level), and is electrically connected to the terminals Dox1 to Doxm of the display panel 101. Each of the switching elements S1 to Sm operates based on the control signal Tscan output by the control circuit 103, and can be configured by combining switching elements such as FETs, for example.

【0111】

In the case of this example, the DC voltage source Vx has a constant voltage such that the drive voltage applied to the unscanned element is equal to or less than the electron emission threshold voltage based on the characteristics of the electron emission element (electron emission threshold voltage). It is set to output.

【0112】

The control circuit 103 has a function of matching the operations of each part so that an appropriate display is performed based on an image signal input from the outside. The control circuit 103 generates Tscan, Tsft, and Tmry control signals for each unit based on the synchronization signal Tsync sent from the synchronization signal separation circuit 106.

【0113】

The synchronous signal separation circuit 106 is a circuit for separating a synchronous signal component and a luminance signal component from an NTSC type television signal input from the outside, and can be configured by using a general frequency separation (filter) circuit or the like. .. The synchronization signal separated by the synchronization signal separation circuit 106 includes a vertical synchronization signal and a horizontal synchronization signal, which are shown here as Tsync signals for convenience of explanation. The luminance signal component of the image separated from the television signal is represented as a DATA signal for convenience. This DATA signal is input to the shift register 104.

【0114】

The shift register 104 is for serial / parallel conversion of the DATA signal serially input in time series for each line of the image, and operates based on the control signal Tsft sent from the control circuit 103. (That is, the control signal Tsft may be rephrased as the shift clock of the shift register 104). The serial / parallel-converted data for one line of the image (corresponding to the drive data for n elements of the electron emitting element) is output from the shift register 104 as an n-solid parallel signal of Id1 to Idn.

【0115】

The line memory 105 is a storage device for storing data for one image line only for a required time, and appropriately stores the contents of Id1 to Idn according to the control signal Tmry sent from the control circuit 103. The stored contents are output as Id'1 to Id'n and input to the modulation signal generator 107.

【0116】

The modulation signal generator 107 is a signal source for appropriately driving and modulating each of the electron emitting elements according to each of the image data Id'1 to Id'n, and the output signal thereof is passed through the terminals Doy1 to Doyn. It is applied to the electron emitting element in the display panel 101.

【0117】

As described above, the electron emitting element of the present invention has the following basic characteristics with respect to the emission current Ie. That is, there is a clear threshold voltage Vth for electron emission, and electron emission occurs only when a voltage equal to or higher than Vth is applied. For a voltage equal to or higher than the electron emission threshold, the emission current also changes according to the change in the voltage applied to the device. From this, when a pulsed voltage is applied to this element, for example, no electron emission occurs even if a voltage equal to or lower than the electron emission threshold voltage is applied, but when a voltage equal to or higher than the electron emission threshold voltage is applied, electrons are emitted. The beam is output. At that time, it is possible to control the intensity of the output electron beam by changing the peak value Vm of the pulse. Further, by changing the pulse width Pw, it is possible to control the total amount of electric charges of the output electron beam.

【0118】

Therefore, as a method of modulating the electron emitting element according to the input signal, a voltage modulation method, a pulse width modulation method, or the like can be adopted. When implementing the voltage modulation method, the modulation signal generator 107 is a circuit of the voltage modulation method that can generate a voltage pulse of a certain length and appropriately modulate the peak value of the voltage pulse according to the input data. Can be used. When implementing the pulse width modulation method, the modulation signal generator 107 is a pulse width modulation method that generates a voltage pulse having a constant peak value and appropriately modulates the width of the voltage pulse according to the input data. A circuit can be used.

【0119】

The shift register 104 and the line memory 105 can be either a digital signal type or an analog signal type. This is because the serial / parallel conversion and storage of the image signal may be performed at a predetermined speed.

【0120】

When the digital signal type is used, it is necessary to convert the output signal DATA of the synchronous signal separation circuit 106 into a digital signal. For this purpose, an A / D converter may be provided in the output section of the synchronous signal separation circuit 106. .. In relation to this, the circuit used for the modulation signal generator 107 is slightly different depending on whether the output signal of the line memory 105 is a digital signal or an analog signal. That is, in the case of the voltage modulation method using a digital signal, for example, a D / A conversion circuit is used for the modulation signal generator 107, and an amplifier circuit or the like is added as necessary. In the case of the pulse width modulation method, the modulation signal generator 107 includes, for example, a high-speed oscillator, a counter that counts the number of waves output by the oscillator, and a comparator that compares the output value of the counter with the output value of the memory. A circuit that combines (comparator) is used. If necessary, an amplifier for amplifying the pulse width-modulated modulated signal output by the comparator to the drive voltage of the electron emitting element can be added.

【0121】

In the case of the voltage modulation method using an analog signal, for example, an amplifier circuit using an operational amplifier or the like can be adopted for the modulation signal generator 107, and a level shift circuit or the like can be added as needed. In the case of the pulse width modulation method, for example, a voltage controlled oscillator circuit (VCO) can be adopted, and if necessary, an amplifier for amplifying the voltage to the drive voltage of the electron emitting element can be added.

【0122】

In the image forming apparatus of the present invention having such a configuration, electron emission occurs by applying a voltage to each electron emitting element via the terminals Dox1 to Doxm and Doy1 to Doyn outside the container. A high voltage is applied to the metal back 85 or the transparent electrode (not shown) via the high voltage terminal 87 to accelerate the electron beam. The accelerated electrons collide with the fluorescent film 84 and emit light to form an image.

【0123】

The configuration of the image forming apparatus described here is an example of the image forming apparatus of the present invention, and various modifications can be made based on the technical idea of the present invention. The NTSC system is mentioned as the input signal, but the input signal is not limited to this, and the PAL, SECAM system, etc., and the TV signal consisting of more scanning lines than these (for example, the MUSE system, etc.) High-definition TV) system can also be adopted.

【0124】

Next, the above-mentioned ladder-shaped arrangement of the electron source and the image forming apparatus will be described with reference to FIGS. 15 and 16.

【0125】

FIG. 15 is a schematic diagram showing an example of an electron source in a ladder type arrangement. In FIG. 15, 110 is an electron source substrate and 111 is an electron emitting element. Reference numerals 112 are common wirings Dx1 to Dx10 for connecting the electron emitting element 111, and these are drawn out as external terminals. A plurality of electron emitting elements 111 are arranged in parallel on the substrate 110 in the X direction (this is called an element row). A plurality of these element rows are arranged to form an electron source. By applying a drive voltage between the common wirings of each element row, each element row can be driven independently. That is, a voltage equal to or higher than the electron emission threshold is applied to the element row in which the electron beam is desired to be emitted, and a voltage equal to or lower than the electron emission threshold is applied to the element row in which the electron beam is not to be emitted. For the common wirings Dx2 to Dx9 located between each element line, for example, Dx2 and Dx3, Dx4 and Dx5, Dx6 and Dx7, and Dx8 and Dx9 can be integrated into the same wiring.

【0126】

FIG. 16 is a schematic view showing an example of a panel structure in an image forming apparatus provided with an electron source in a ladder type arrangement. 120 is a grid electrode, 121 is an opening for electrons to pass through, Dox1 to Doxm are terminals outside the container, and G1 to Gn are terminals outside the container connected to the grid electrode 120. Reference numeral 110 denotes an electron source board in which the common wiring between each element row is the same wiring. In FIG. 16, the same parts as those shown in FIGS. 11 and 15 are designated by the same reference numerals as those shown in these figures. The major difference between the image forming apparatus shown here and the image forming apparatus having a simple matrix arrangement shown in FIG. 11 is whether or not the grid electrode 120 is provided between the electron source substrate 110 and the face plate 86.

【0127】

In FIG. 16, a grid electrode 120 is provided between the substrate 110 and the face plate 86. The grid electrodes 120 are for modulating the electron beam emitted from the electron emitting element 111, and each of the grid electrodes 120 is for passing the electron beam through a striped electrode provided orthogonal to the element row of the ladder type arrangement. A circular opening 121 is provided for each element. The shape and arrangement position of the grid electrodes are not limited to those shown in FIG. For example, a large number of passage ports may be provided as openings in a mesh shape, and grid electrodes may be provided around or in the vicinity of the electron emitting element.

【0128】

The outer container terminals Dox1 to Doxm and the grid outer container terminals G1 to Gn are electrically connected to a control circuit (not shown).

【0129】

In the image forming apparatus of this example, the modulation signals for one line of the image are simultaneously applied to the grid electrode rows in synchronization with the sequential driving (scanning) of the element rows one by one. As a result, it is possible to control the irradiation of each electron beam to the phosphor and display the image one line at a time.

【0130】

The image forming apparatus of the present invention described above can be used as a display device for television broadcasting, a display device for a video conferencing system, a computer, or the like, as well as an image forming apparatus as an optical printer configured by using a photosensitive drum or the like. Can be used.

【0131】

[Example]

Hereinafter, the present invention will be described with reference to specific examples, but the present invention is not limited to these examples, and replacement of each element within the range in which the object of the present invention is achieved can be achieved. Includes those with design changes.

【0132】

[Example 1] The basic configuration of the electron emitting device according to this embodiment is the same as that in FIG. FIG. 17 is a substrate in which 10 elements having the same shape as that of FIG. 1 are arranged. Further, FIG. 18 is an explanatory diagram showing a method of manufacturing the electron emitting device in the first embodiment.

【0133】

Hereinafter, the manufacturing method of the electron emitting device in this embodiment will be described in order with reference to FIGS. 1, 17 and 18.

【0134】

Process-1 A photoresist (RD-2000N-41 manufactured by Hitachi Kasei Co., Ltd.) was formed on the cleaned blue plate glass substrate 1 as a pattern of element electrodes, and Pt having a thickness of 500 Å was deposited by a vacuum deposition method. The photoresist pattern was dissolved in an organic solvent, the sedimentary film was lifted off, and device electrodes 2 and 3 were formed. The element electrode spacing L was set to 30 μm. Further, it was washed with pure water.

【0135】

Process-2 The substrate 1 on which the element electrodes 2 and 3 were formed was washed with warm water.

【0136】

Process-3 The substrate prepared in step 2 was placed in the chamber, the inside of the chamber was replaced with nitrogen under atmospheric pressure, and then dimethyldiethoxysilane was introduced as an organic compound gas and left to stand. At this time, the temperature was 25 ° C and the partial pressure was 13 mmHg.

【0137】

The treatment is performed while measuring and inspecting the surface energy state of the substrate on the spot, and the method is to use an aqueous solution containing an organic metal in a monitor region provided in advance on the substrate without removing the substrate from the chamber. The method of measuring the contact angle of the above was used. Therefore, in the chamber used in this step, as a means for applying the solution for measuring the contact angle onto the substrate, a microsyringe that can be operated from outside the chamber and the shape of the applied droplets are observed. A CCD camera is installed as a means.

【0138】

Further, the means for measuring these contact angles is movable in order to enable the measurement of the contact angles a plurality of times. Of course, it is possible to perform a plurality of measurements by installing a plurality of sets of contact angle measuring means.

【0139】

For the measurement of the contact angle, an appropriate amount of droplets of an aqueous solution containing an organic metal was applied onto the substrate, and an image of the droplets on the substrate captured by the CCD camera was image-processed to calculate the contact angle.

【0140】

During the process, the surface energy state is measured and inspected several times, the measured surface energy value is compared with the reference value, and when the reference value is reached, this step (adjustment of surface energy) is completed, so it is organic. The introduction of the compound gas was stopped, replaced with nitrogen gas, and left to stand.

【0141】

The timing and number of times to measure and inspect the surface energy state are determined by considering the standard time required for the surface energy of the substrate to reach the desired value and the extent to which the variation range of the surface energy is allowed. However, in this embodiment, the contact angle is measured every 2 minutes from the time 50 minutes after the start of the treatment, and the treatment is terminated when the value of the contact angle shows a value of 44 degrees or more.

【0142】

As a result of treating 5 substrates by the method of this example, the time required to reach the desired value was 3 for 60 minutes and 2 for 64 minutes.

【0143】

Process-4 Droplets of an aqueous solution of a Pd organometallic compound (Pd concentration 0.15%), isopropyl alcohol 20%, and ethylene glycol 1% were applied four times between the element electrodes 2 and 3 by a bubble jet inkjet method.

【0144】

Process-5 The sample prepared in step-4 was calcined in the air at 350 ° C. In this way, the conductive film 4 made of PdO was formed. Through the above steps, the element electrodes 2 and 3 and the conductive film 4 and the like were formed on the substrate 1.

【0145】

Next, this sample was placed in the measuring device shown in Fig. 8, exhausted by a vacuum pump, and 1.3 × 10^-6After reaching the degree of vacuum of Pa, in order to measure the resistance of the conductive film to the element electrodes, a pulsed voltage of 0.1 V is applied between the element electrodes 2 and 3 of each element from the power supply, and each element electrode. The current flowing between them was measured. The voltage waveform of the pulse had a pulse width of 0.1 msec and a pulse interval of 10 msec, and the measurement was repeated 10 times, and the resistance value was obtained from the average value.

【0146】

As an example, the vacuum processing apparatus shown in FIG. 8 can measure the voltage of the anode electrode in the range of 1 kV to 10 kV and the distance H between the anode electrode and the electron emitting element in the range of 2 mm to 8 mm.

【0147】

[Comparative Example 1] Same as Example 1 except that the surface energy was adjusted only by time control (fixed for 60 minutes) without measuring and inspecting the surface energy state on the spot in Step 3 of Example 1. A conductive film of the electron emitting element was formed in the above step. At this time, for comparison, the contact angle after the above step-3 was completed was measured.

【0148】

Table 1 shows the measurement results of the contact angle in the middle of wo and the measurement results of resistance, etc. after completing Step 3 of Example 1 and Comparative Example 1. The results in Table 1 are the average values of 10 elements, and 5 substrates were treated for each.

【0149】

[table 1]

<img file="JP2000251663A_D0001.tif" />【0150】

From Table 1, the following was found. In adjusting the surface energy in step-3, the surface energy state is measured and inspected on the spot, the measured surface energy (contact angle) is compared with the reference value, and when the reference value is reached, this step is performed. By completing (adjustment of surface energy), it can be seen that the variation of surface energy between substrates is reduced as compared with the case where the surface energy is adjusted only by time management.

【0151】

Further, the resistance value of the conductive film also has little variation among the substrates. It is considered that this is because the shape of the conductive film was stabilized when the aqueous solution containing the organic metal was applied as droplets by the inkjet method, and as a result, the resistance value of the conductive film also had little variation among the substrates.

【0152】

[Example 2] This example is an example in which an electron emitting element is produced by further performing several steps after the step -5 of the first embodiment. The same process was performed for the electron emitting element of Comparative Example 1.

【0153】

Hereinafter, the steps after step 5 will be described step by step. In this embodiment, an element having the same shape as that shown in FIG. 2 was manufactured.

【0154】

Process-6 Following step 5, a forming process was performed in the measuring apparatus shown in FIG. When energization was applied between the element electrodes 2 and 3, cracks were formed at the site of the conductive film 4. The voltage waveform of the energization forming is a pulse waveform, and a voltage pulse that increases the pulse peak value from 0V in steps of 0.1V is applied. The pulse width of the voltage waveform was 1 msec, the pulse interval was 10 msec, and it was a triangular wave. The energization forming process was terminated when the resistance value of the conductive film reached 1 MΩ or more. FIG. 19 shows the forming waveform used in this example. In the element electrodes 2 and 3, a voltage is applied with one electrode having a low potential and the other having a high potential side.

【0155】

Process-7 The device that had been formed was subjected to an activation step. As described above, the activation step is a step in which the element current If and the emission current Ie are remarkably changed by forming carbon inside the crack formed by forming so that the crack becomes narrower.

【0156】

In the activation process, acetone gas is placed in the measuring device 1.3 x 10^-1It was introduced up to Pa, and the application of a rectangular wave pulse with a pulse peak value of 15 V, a pulse width of 1 msec, and a pulse interval of 10 msec was repeated for 20 minutes. Figure 20 shows the pulse waveform used in the activation step. In this embodiment, low and high potentials were alternately applied to the element electrodes 2 and 3 so as to be alternated at each pulse interval.

【0157】

Process-8 Subsequently, a stabilization step was performed. The stabilization step is a step of exhausting the organic gas existing in the atmosphere in the vacuum vessel, suppressing the deposition of carbon or a carbon compound, and stabilizing the element current If and the emission current Ie. The entire vacuum vessel was heated at 250 ° C. to exhaust the organic substance molecules adsorbed on the inner wall of the vacuum vessel and the electron emitting element. At this time, the degree of vacuum is 1.3 × 10.^-6It was Pa. Then, the characteristics of the electron emitting device were measured at this degree of vacuum.

【0158】

[Comparative Example 2] As described above, the electron emitting element of Comparative Example 1 was also subjected to a forming step, an activation step, and a stabilization step in the same manner as in Example 2.

【0159】

The characteristics of the electron emitting elements in each of the methods of Example 2 and Comparative Example 2 are the average values of 10 elements measured for each of the five substrates in Example 2, and the variation in the five substrates is the element current If. Was 2.0mA ± 0.02mA, and the emission current Ie was 3.0μA ± 0.04μA. On the other hand, the characteristics of the electron emitting device of Comparative Example 2 were that the element current If was 1.9 mA ± 0.1 mA and the emission current Ie was 2.5 μA ± 0.1 μA. As a result, it was found that the electron emission characteristics of Example 2 had less variation and were good characteristics as compared with Comparative Example 2.

【0160】

As described above, when the surface energy adjustment step of the substrate is performed, the surface energy state is measured and inspected on the spot, the measured surface energy (contact angle) is compared with the reference value, and the reference value is reached. It was found that by completing this step (adjustment of surface energy) at this point, it also contributes to the reduction of the fluctuation of the characteristics of the electron emitting element.

【0161】

[Example 3] This example is an example in which the amount of carbon on the substrate is measured as a means for inspecting and measuring the surface energy state of the substrate on the spot.

【0162】

An electron emitting device was manufactured in the same manner except for Step-3 of Examples 1 and 2.

【0163】

In this example, step-3 was performed as follows.

【0164】

The substrate prepared in Step 2 of Example 1 was placed in a chamber, the inside of the chamber was replaced with nitrogen under atmospheric pressure, and then an organic compound gas was introduced and left to stand. The organic compound gas used and its partial pressure are the same as in Example 1.

【0165】

The treatment was carried out while measuring and inspecting the surface energy state on the spot, and the method used the measurement of the amount of carbon on the substrate. The amount of carbon was measured in a monitor region provided in advance on the substrate, but it may be measured in a region where a conductive film is actually formed.

【0166】

In the chamber used in this step, a surface reflection type infrared absorption spectrum measuring device is incorporated as a means for measuring the amount of carbon on the substrate. Further, as a means for measuring the amount of carbon on the surface of the substrate, a means such as ellipsometry can be used.

【0167】

In actually using this method, a test substrate was used, surface treatment was performed with an organic compound gas in advance under some conditions, and step-4 was performed to obtain the shape of the droplets imparted onto the substrate. The relationship with the amount of carbon on the substrate (measured peak value of infrared absorption) at the end of the surface treatment was investigated, and the amount of carbon on the substrate at the end of the surface treatment was determined.

【0168】

In this method, the surface energy state (adhesion amount of carbon component) is always measured and inspected during the treatment, and the measured carbon component adhesion amount (measured peak value of infrared absorption) is used as a reference value. In comparison, when the reference value was reached, the introduction of the organic compound gas was stopped, replaced with nitrogen gas, and left to stand in order to end this step (adjustment of surface energy). FIG. 21 shows a diagram illustrating the process of this embodiment.

【0169】

Similar to Examples 1 and 2, the electron emitting element produced in this example also has a stable shape when an aqueous solution containing an organic metal is applied as a droplet by an inkjet method, and the resistance value of the conductive film is also different for each substrate. It was found that there was little variation in the electron emission characteristics, and there was little variation in the electron emission characteristics, which were good characteristics.

【0170】

[Example 4] In this embodiment, as a means for inspecting and measuring the surface energy state of the substrate on the spot, droplets of a solution containing an organic metal are applied to the substrate by an inkjet method, and the added droplets are subjected to. This is an example using the measurement of the dot diameter on the substrate.

【0171】

An electron emitting device was manufactured in the same manner except for Step-3 of Examples 1 and 2.

【0172】

In this example, step-3 was performed as follows.

【0173】

The substrate prepared in step 2 was placed in a chamber, the inside of the chamber was replaced with nitrogen under atmospheric pressure, and then an organic compound gas was introduced and left to stand. The organic compound gas used and its partial pressure are the same as in Example 1.

【0174】

The treatment is performed while measuring and inspecting the surface energy state on the spot, and the method is to apply droplets of a solution containing an organic metal to a substrate by an inkjet method, and dots on the substrate of the applied droplets. Diameter measurement was used.

【0175】

Therefore, in the chamber used in this step, an inkjet head that can be operated from outside the chamber as a means for applying a solution for measuring the dot diameter onto the substrate and for observing the dot diameter of the applied droplets. A CCD camera is installed as a means. These means are movable because they allow multiple measurements. Of course, it is possible to perform a plurality of measurements by having a plurality of sets of measuring means. The dot diameter was measured by forming droplets of an organic metal-containing aqueous solution on a substrate from an inkjet head and performing image processing on an image of the droplets on the substrate captured by a CCD camera to measure the dot diameter.

【0176】

It is also possible to strike a plurality of dots for one measurement and use the average value as the dot diameter value.

【0177】

During the treatment, the surface energy state is measured and inspected several times, the measured dot diameter is compared with the reference value, and when the reference value is reached, this step (adjustment of surface energy) is completed. The introduction of the compound was stopped, replaced with nitrogen gas, and left to stand. FIG. 22 shows a diagram illustrating the process of this embodiment.

【0178】

In this example, the reference value of the dot diameter was 80 μm in diameter. The reference value is set in consideration of a desired conductive film pattern, film thickness, ink to be used, and the like.

【0179】

The timing and number of times the surface energy state is measured and inspected are determined by considering the standard time required for the surface energy of the substrate to reach the desired value and the extent to which the surface energy variation range is allowed. However, in this embodiment, the dot diameter is measured every 2 minutes from the time 50 minutes after the start of the treatment, and the treatment is terminated when the dot diameter value shows a value of 80 μm (diameter) or more. ..

【0180】

Similar to Examples 1 and 2, the electron emitting element produced in this example also has a stable shape when an aqueous solution containing an organic metal is applied as a droplet by an inkjet method, and the resistance value of the conductive film is also different for each substrate. It was found that there was little variation in the electron emission characteristics, and there was little variation in the electron emission characteristics, which were good characteristics.

【0181】

[Example 5] This example is an example in which an image forming apparatus is created according to the process sequence shown in FIG. In the process sequence shown in FIG. 13, only the electron source substrate closely related to this embodiment is described in detail. FIG. 23 (a) is a plan view of a part of the electron source, and FIG. 23 (b) is a vertical sectional view thereof. In FIG. 23, 191 is a substrate, 198 is a row direction wiring corresponding to Dxm, 199 is a column direction wiring corresponding to Dyn, 194 is a conductive film, 192 and 193 are element electrodes, and 197 is an interlayer insulating layer. The image forming apparatus of this embodiment is the same as that shown in FIG. 10, but a substrate is used as the rear plate.

【0182】

Hereinafter, the method for manufacturing the electron source substrate will be specifically described in accordance with the process order.

【0183】

Process-1 The element electrodes 192 and 193 were created on the cleaned blue plate glass substrate 1 by the offset printing method. The element electrode spacing L was 20 μm, and the element electrode width W was 125 μm. Next, a row direction wiring 198 having a thickness of 20 μm, an interlayer insulating layer 197 having a thickness of 30 μm, and a column direction wiring 199 having a thickness of 20 μm were sequentially prepared by a screen printing method.

【0184】

Process-2 The substrate on which the row direction wiring, column direction wiring, and element electrodes prepared in step 1 were formed was washed with warm water.

【0185】

Process-3 Next, the substrate was placed in the chamber, the inside of the chamber was replaced with nitrogen under atmospheric pressure, and then the organic compound gas was introduced and left to stand. The organic compound gas used and its partial pressure were the same as in Example 1.

【0186】

The treatment was carried out by the same method and apparatus as in Step 3 of Example 2. As a method of measuring and inspecting the surface energy state on the spot, a method of measuring the contact angle with a solution containing an organometallic in a monitor region provided in advance on the substrate was used without removing the substrate from the chamber. ..

【0187】

During the process, the surface energy state is measured and inspected several times, the measured surface energy value is compared with the reference value, and when the reference value is reached, this step (adjustment of surface energy) is completed, so it is organic. The introduction of the compound gas was stopped, replaced with nitrogen gas, and left to stand.

【0188】

Process-4 Droplets of an aqueous solution of 0.15% Pd organometallic compound, 20% isopropyl alcohol, and 1% ethylene glycol were applied four times between each element electrode and the element electrode by an inkjet method such as a piezojet method.

【0189】

Process-5 The sample prepared in step-4 was calcined in the air at 350 ° C. A conductive film made of PdO thus formed was formed. By the above steps, row and column direction wirings 98,99, element electrodes 92,93, conductive film 94 and the like were formed on the substrate 1.

【0190】

Process-6 Next, a face plate was formed. The face plate was constructed by forming a fluorescent film on which a phosphor was arranged and a metal back on the inner surface of a glass substrate. The arrangement of the phosphors was provided with black stripes between the phosphors of the three primary color phosphors. As the material for the plaque stripe, a commonly used material containing graphite as a main component was used. All of these were formed by the screen printing method.

【0191】

Process-7 The substrate formed in steps -1 to 5 was used as a rear plate, and the face plate was sealed via a support frame. An exhaust pipe used for exhaust is bonded to the support frame in advance.

【0192】

Process-8 1.3 × 10^-6After exhausting to Pa, forming was performed for each line with a manufacturing device that can supply voltage to each element from each wiring Dxm and Dyn. The forming conditions are the same as in Example 2.

【0193】

Process-9 1.3 × 10^-5After exhausting to Pa, add 1.3 x 10 acetone.^-1Pa is introduced from the exhaust pipe, and a voltage is applied to each element so that the same pulse voltage as in Example 2 is applied to each element in a manufacturing device that can supply voltage to each element from each wiring Dxm and Dyn. Then, the activation step was carried out. When the voltage was applied for 25 minutes on each line and the element current on each line reached an average of 3 mA, the activation step was completed.

【0194】

Process-10 Subsequently, after sufficiently exhausting from the exhaust pipe, the entire container was exhausted while heating at 250 ° C. for 3 hours. Finally, the getter was flushed and the exhaust pipe was sealed.

【0195】

An image forming apparatus configured by using an electron source having a simple matrix arrangement created as described above is provided with a drive circuit for performing television display based on the NTSC television signal shown in FIG.

【0196】

With such a drive circuit, electron emission occurs by applying a voltage to each electron emitting element of the display panel via the terminals Dox1 to Doxm and Doy1 to Doyn outside the container. A high voltage is applied to the metal back via the high voltage terminal 87 to accelerate the electron beam. The accelerated electrons collide with the fluorescent film and emit light to form an image.

【0197】

By inputting the NTSC signal, the image forming apparatus formed by the above steps has little variation in brightness, a stable image forming apparatus has good reproducibility, and a high yield can be manufactured.

【0198】

[Example 6] FIG. 24 shows the image forming apparatus of the present invention configured so that image information provided by various image information sources such as television broadcasting can be displayed on a display panel (FIG. 11). It is a figure which shows an example.

【0199】

In the figure, 201 is the display panel, 1001 is the drive circuit of the display panel, 1002 is the display controller, 1003 is the multiplexer, 1004 is the decoder, 1005 is the input / output interface circuit, 1006 is the CPU, 1007 is the image generation circuit, 1008 and 1009 and 1010. Is an image memory interface circuit, 1011 is an image input interface circuit, 1012 and 1013 are TV signal receiving circuits, and 1014 is an input unit.

【0200】

When the image forming apparatus receives a signal including both video information and audio information, such as a television signal, the image forming apparatus naturally reproduces the sound at the same time as displaying the image. Circuits and speakers related to reception, separation, reproduction, processing, storage, etc. of audio information that are not directly related to the features will not be described.

【0201】

Hereinafter, the functions of each part will be described along with the flow of the image signal.

【0202】

First, the TV signal receiving circuit 1013 is a circuit for receiving a TV signal transmitted by using a wireless transmission system such as radio waves or spatial optical communication.

【0203】

The method of receiving the TV signal is not particularly limited, and any method such as NTSC method, PAL method, SECAM method, etc. may be used. Further, a TV signal composed of a larger number of scanning lines than these, for example, a so-called high-definition TV such as the MUSE method, is a signal suitable for taking advantage of the display panel suitable for increasing the area and the number of pixels. It is the source.

【0204】

The TV signal received by the TV signal receiving circuit 1013 is output to the decoder 1004.

【0205】

The TV signal receiving circuit 1012 is a circuit for receiving a TV signal transmitted by using a wired transmission system such as a coaxial cable or an optical fiber. Similar to the TV signal receiving circuit 1013, the method of receiving the TV signal is not particularly limited, and the TV signal received by this circuit is also output to the decoder 1004.

【0206】

The image input interface circuit 1011 is a circuit for capturing an image signal supplied from an image input device such as a TV camera or an image reading scanner, and the captured image signal is output to the decoder 1004.

【0207】

The image memory interface circuit 1010 is a circuit for capturing an image signal stored in a videotape recorder (hereinafter abbreviated as VTR), and the captured image signal is output to the decoder 1004.

【0208】

The image memory interface circuit 1009 is a circuit for capturing an image signal stored in a video disc, and the captured image signal is output to the decoder 1004.

【0209】

The image memory interface circuit 1008 is a circuit for capturing an image signal from a device that stores still image data, such as a still image disk, and the captured still image data is input to the decoder 1004.

【0210】

The input / output interface circuit 1005 is a circuit for connecting this display device to an external computer, a computer network, or an output device such as a printer. It is possible not only to input / output image data and character / graphic information, but also to input / output control signals and numerical data between the CPU 1006 provided in this image forming apparatus and the outside in some cases. ..

【0211】

The image generation circuit 1007 is based on image data, character / graphic information input from the outside via the input / output interface circuit 1005, or image data, character / graphic information output from the CPU 1006, and display image data. Is a circuit for generating. Inside this circuit, for example, a rewritable memory for storing image data and character / graphic information, a read-only memory for storing image patterns corresponding to character codes, a processor for performing image processing, etc. The circuits necessary for image generation are built in, including.

【0212】

The display image data generated by this circuit is output to the decoder 1004, but in some cases, it can also be output to an external computer network or printer via the input / output interface circuit 1005.

【0213】

The CPU1006 mainly performs operations related to operation control of this display device and generation, selection, and editing of display images.

【0214】

For example, a control signal is output to the multiplexer 1003, and an image signal to be displayed on a display panel is appropriately selected or combined. In that case, a control signal is generated for the display panel controller 1002 according to the image signal to be displayed, and the display device such as the screen display frequency, scanning method (for example, interlaced or non-interlaced), and the number of scanning lines on one screen is displayed. Control the operation as appropriate. Further, the image data and character / graphic information can be directly output to the image generation circuit 1007, or the image data and character / graphic information can be output by accessing an external computer or memory via the input / output interface circuit 1005. input.

【0215】

The CPU1006 may be involved in work for other purposes. For example, it may be directly involved in a function of generating or processing information, such as a personal computer or a word processor. Alternatively, as described above, it may be connected to an external computer network via the input / output interface circuit 1005, and work such as numerical calculation may be performed in cooperation with an external device.

【0216】

The input unit 1014 is for the user to input commands, programs, data, etc. to the CPU 1006. For example, in addition to a keyboard and a mouse, various input devices such as a joystick, a barcode reader, and a voice recognition device can be used. It can be used.

【0217】

The decoder 1004 is a circuit for inversely converting various image signals input from the 1007 to 1013 into three primary color signals, or a luminance signal, an I signal, and a Q signal. As shown by the dotted line in the figure, it is desirable that the decoder 1004 has an image memory inside. This is for handling television signals that require an image memory for reverse conversion, such as the MUSE method.

【0218】

By providing an image memory, it becomes easy to display a still image. Alternatively, in cooperation with the image generation circuit 1007 and the CPU 1006, there is an advantage that image processing and editing such as thinning, interpolation, enlargement, reduction, and composition of images become easy.

【0219】

The multiplexer 1003 appropriately selects a display image based on the control signal input from the CPU 1006. That is, the multiplexer 1003 selects a desired image signal from the inversely converted image signals input from the decoder 1004 and outputs the desired image signal to the drive circuit 1001. In that case, by switching and selecting an image signal within the one-screen display time, it is possible to divide one screen into a plurality of areas and display different images depending on the area, as in a so-called multi-screen television. ..

【0220】

The display panel controller 1002 is a circuit for controlling the operation of the drive circuit 1001 based on the control signal input from the CPU 1006.

【0221】

As related to the basic operation of the display panel, for example, a signal for controlling the operation sequence of the drive power supply (not shown) of the display panel is output to the drive circuit 1001. As related to the drive method of the display panel, for example, a signal for controlling the screen display frequency and the scanning method (for example, interlaced or non-interlaced) is output to the drive circuit 1001. In some cases, a control signal related to image quality adjustment such as brightness, contrast, color tone, and sharpness of the displayed image may be output to the drive circuit 1001.

【0222】

The drive circuit 1001 is a circuit for generating a drive signal applied to the display panel 201, and operates based on an image signal input from the multiplexer 1003 and a control signal input from the display panel controller 1002. Is.

【0223】

Although the functions of each part have been described above, the image forming apparatus can display the image information input from various image information sources on the display panel 201 by the configuration illustrated in FIG. 24. That is, various image signals such as television broadcasts are inversely converted by the decoder 1004, appropriately selected by the multiplexer 1003, and input to the drive circuit 1001. On the other hand, the display controller 1002 generates a control signal for controlling the operation of the drive circuit 1001 according to the image signal to be displayed. The drive circuit 1001 applies a drive signal to the display panel 201 based on the image signal and the control signal. As a result, the image is displayed on the display panel 201. These series of operations are collectively controlled by the CPU 1006.

【0224】

In this image forming apparatus, not only the image memory built in the decoder 1004, the image generation circuit 1007, and the information selected from the information are displayed, but also the image information to be displayed is, for example, enlarged, reduced, and rotated. It is also possible to perform image processing such as moving, edge enhancement, thinning, interpolation, color conversion, image aspect ratio conversion, and image editing such as compositing, erasing, connecting, replacing, and fitting. .. Further, although not particularly mentioned in the description of this embodiment, a dedicated circuit for processing or editing audio information may be provided as in the case of the above image processing and image editing.

【0225】

Therefore, this image forming apparatus includes a television broadcast display device, a video conference terminal device, an image editing device that handles still images and moving images, a computer terminal device, an office terminal device such as a word processor, a game machine, and the like. It is possible to combine the functions of the above with one unit, and the range of application is extremely wide for industrial or consumer use.

【0226】

The display device shown in FIG. 24 can be variously modified based on the technical idea of the present invention. For example, among the components shown in FIG. 24, circuits related to functions that are not necessary for the purpose of use may be omitted. On the contrary, further components may be added depending on the purpose of use. For example, when the present display device is applied as a TV telephone, it is preferable to add a TV camera, a voice microphone, a illuminator, a transmission / reception circuit including a modem, and the like to the components.

【0227】

In this display device, the depth of the display device can be reduced because it is easy to reduce the thickness of the display panel using the electron emitting element as the electron beam source. In addition, since it is easy to increase the area, the brightness is high, and the viewing angle characteristics are excellent, it is possible to display a powerful image with a sense of realism with good visibility. In addition, by using an electron source equipped with a large number of electron emitting elements having uniform characteristics, a high-quality color flat television that is extremely uniform and bright as compared with a conventional display device has been realized.

【0228】

[Effect of the invention]

As described above, according to the present invention, an electron emitting element having good electron emitting characteristics can be manufactured with good yield.

【0229】

In addition, in an electron source that emits electrons in response to an input signal by arranging a large number of electron emitting elements, it can be manufactured stably and with good yield, and due to the improvement of electron emitting characteristics, power consumption is low and peripheral circuits are used. It is possible to provide an inexpensive device by reducing the burden such as.

【0230】

Further, in an image forming apparatus using such an electron source, a low current, bright and high-quality image forming apparatus, for example, a color flat television is realized.

[Simple explanation of drawings]

[Figure 1]

It is a schematic diagram which shows an example of the electron emission element which concerns on this invention.

[Figure 2]

It is a schematic diagram which shows another example of the electron emission element which concerns on this invention.

[Fig. 3]

It is a figure for demonstrating the manufacturing method of the electron emitting element of this invention.

[Fig. 4]

It is a figure explaining the process of adjusting the surface energy of the substrate in this invention.

[Fig. 5]

It is a block diagram which shows the apparatus for adjusting the surface energy of the substrate in this invention.

[Fig. 6]

It is a schematic diagram which shows the installation example of the surface state monitor of the substrate in this invention.

[Fig. 7]

It is a schematic diagram which shows an example of the voltage waveform in the energization process which can be adopted in the manufacture of the electron emission element of this invention.

[Fig. 8]

It is a schematic block diagram which shows an example of the vacuum processing apparatus (measurement evaluation apparatus) which can be used for manufacturing the electron emission element of this invention.

[Fig. 9]

It is a figure which shows the electron emission characteristic of the electron emission element of this invention.

[Fig. 10]

It is a schematic diagram which shows an example of the electron source of the simple matrix arrangement of this invention.

[Fig. 11]

It is a schematic diagram which shows an example of the display panel of the image forming apparatus of this invention.

[Fig. 12]

It is a schematic diagram which shows an example of the fluorescent film in a display panel.

[Fig. 13]

It is a figure explaining the manufacturing process of the image forming apparatus of this invention.

[Fig. 14]

It is a block diagram which shows an example of the drive circuit for displaying in the image forming apparatus of this invention according to the television signal of the NTSC system.

[Fig. 15]

It is a schematic diagram which shows an example of the electron source of the ladder type arrangement of this invention.

[Fig. 16]

It is a schematic diagram which shows an example of the display panel of the image forming apparatus of this invention.

[Fig. 17]

It is a schematic diagram which shows the substrate in which a plurality of electron emission elements of this invention are arranged.

[Fig. 18]

It is a figure explaining the process of adjusting the surface energy of the substrate in Example 1. FIG.

[Fig. 19]

It is a schematic diagram which shows the voltage waveform in the energization forming process adopted in Example 2.

[Fig. 20]

It is a schematic diagram which shows the voltage waveform in the activation process adopted in Example 2.

[Fig. 21]

It is a figure explaining the process of adjusting the surface energy of the substrate in Example 3. FIG.

[Fig. 22]

It is a figure explaining the step of adjusting the surface energy of the substrate in Example 4.

[Fig. 23]

It is a schematic diagram which shows a part of the electron source of Example 5.

[Fig. 24]

It is a block diagram of the image display device of Example 6.

[Fig. 25]

It is a schematic diagram of the surface conduction type electron emitting element of the conventional example.

[Explanation of symbols]

1 board A few element electrodes 4 Conductive film 5 Electron emission section 31 chamber 50 Ammeter for measuring element current If 51 Power supply for applying the element voltage Vf to the electron emitting element 52 Ammeter for measuring the emission current Ie emitted from the electron emission section 5. 53 High voltage power supply for applying voltage to anode electrode 54 54 Anode electrode for capturing electrons emitted from electron emitting unit 5 55 Vacuum container 56 Exhaust pump 61 A substrate on which element electrodes, etc. are formed 63 Surface energy measuring means 64 Comparison circuit for comparing measured values with reference values 65 Surface energy regulator control circuit 71 Electron source board 72 X direction wiring 73 Y direction wiring 74 Electron emitting element 75 Wiring 81 rear plate 82 Support frame 83 Glass substrate 84 Fluorescent film 85 metal back 86 face plate 87 High voltage terminal 88 enclosure 91 Black conductive material 92 Fluorescent material 101 display panel 102 scanning circuit 103 control circuit 104 shift register 105 line memory 106 Synchronous signal separation circuit 107 Modulated signal generator Vx, Va DC voltage source 110 electron source board 111 Electron emitting element 112 Common wiring for wiring electron emitting elements 120 grid electrodes 121 Aperture for electrons to pass through 181 Monitor area 182 Electron emitting element formation region 191 board 192,193 Element electrode 194 Conductive membrane 197 Interlayer insulation layer Row direction wiring corresponding to 198 Dxm Column direction wiring corresponding to 199 Dyn 201 display panel 1001 Display panel drive circuit 1002 display controller 1003 multiplexer 1004 decoder 1005 I / O interface circuit 1006 CPU 1007 Image generation circuit 1008, 1009, 1010 Image memory interface circuit 1011 Image input interface circuit 1012, 1013 TV signal receiving circuit 1014 Input section