JPH11191369A - Electron emitting element and manufacture of image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electron emitting element having safe and uniform electron emitting characteristic by use of a frit glass paste having no influence on the element by using a glass frit agent consisting of a glass frit of main component, an inorganic particle of thickener, and a solvent or water. SOLUTION: An organic metal solution is applied to a substrate 1 having element electrodes 2, 3 formed thereon by ink jet, and heated and baked to form a conductive thin film. When a current is carried between the element electrodes 2, 3 as a forming method by current-carrying, an electron emitting part 5 consisting of a structurally changed high-resistance crack is formed in the position of a conductive thin film 4. The element after forming is preferably subjected to the processing of activating step. When silica fine particle is used as the thickener for a mixture of frit glass 8, generation of a reductive gas by combustion decomposition can be avoided to eliminate the forming failure. Since the discharge current of this element is increased by applying a threshold voltage, the electron emission can be controlled by an input signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device having an electron-emitting device and a display device used therefor, and more particularly, to sealing an outer frame and an atmospheric pressure-resistant spacer using frit glass (low-melting glass powder). And an electron-emitting device used for the flat-panel image display device.

[0002]

2. Description of the Related Art Conventionally, two types of electron-emitting devices using a thermionic electron-emitting device and a cold-cathode electron-emitting device have been known. The cold cathode electron-emitting device includes a field emission type (hereinafter, referred to as an FE type), a metal / insulating layer / metal type (hereinafter, referred to as an MIM type), a surface conduction electron-emitting device, and the like.

As an example of the FE type, WPDyke & W.W.Dola
n, “Field Emission”, Advance in Electron Physics,
8,89 (1956) or CASpindt, “PHYSICAL Properti
es ofthin-film field emission cathodes with molybd
enium cones ", J. Appl. Phys., 47, 5248 (1976). An example of the MIM type is CA.
Mead, “Operation of Tunnel-Emission Devices”, J. Ap
pl.Phys., 32, 646 (1961) and the like are known.

Examples of the surface conduction electron-emitting device type include:
M.I.Elinson, Radio Eng. Electron Phys., 10, 1290 (1965)
And the like. Surface conduction electron-emitting device
Is a thin film of small area formed on a substrate,
Utilize the phenomenon that electron emission occurs by passing current
Things. As an example of this surface conduction electron-emitting device
Is SnO by Elinson et al._TwoUsing a thin film,
Au thin film [G. Dittmer: “Thin Solis Films,”
9,317 (1972)], In _TwoO_Three/ SnO_TwoBy thin film [M.Hart
well and C.G.Fonstad: “IEEE Trans.E D Conf.”, 519
(1975)], using a carbon thin film [Hisashi Araki et al .: Vacuum,
Vol. 26, No. 1, page 22 (1983)] and the like.
You.

Conventionally, in these surface conduction electron-emitting devices, the electron-emitting portion 5 is subjected to an energization process called energization forming before the conductive thin film 4 is emitted.
It was common to form That is, energization forming means applying a DC voltage or a very slowly increasing voltage, for example, about 1 V / min, to both ends of the conductive thin film 4 and energizing the conductive thin film 4 to locally destroy, deform or alter the conductive thin film. The purpose is to form the electron-emitting portion 5 in a state of high resistance. In the electron emitting portion 5, a crack is generated in a part of the conductive thin film 4, and electrons are emitted from the vicinity of the crack. The surface conduction type electron-emitting device that has been subjected to the energization forming process causes the electron-emitting portion 5 to emit electrons by applying a voltage to the conductive thin film 4 and causing a current to flow through the device.

Further, in order to improve electron emission characteristics,
A process referred to as “activation” may be performed. By the activation treatment, a (carbon) film made of carbon or a carbon compound is formed around the cracks in the electron-emitting portion. In this step, there is a method in which a pulse voltage is applied to the device in an atmosphere containing an organic substance to deposit carbon and a carbon compound around the crack. Furthermore, in order to obtain stable electron emission characteristics, the carbon and the carbon compound are prevented from unnecessarily accumulating,
A step called “stabilization” may be applied.

The above-described surface conduction electron-emitting device has an advantage that a large number of devices can be arranged and formed over a large area because the structure is simple and the production is easy. Therefore, various applications that make use of this feature are being studied. For example, a charged beam source, a display device, and the like can be given. As an example in which a large number of surface conduction electron-emitting devices are arranged and formed, as described later, surface conduction electron-emitting devices are arranged in parallel,
Electron sources (for example, JP-A-64-31332, JP-A-1-257552, and JP-A-1-257552) in which both ends of each element are connected by wiring (also referred to as common wiring), and rows each connected to each other are arranged in many rows.
83749).

In recent years, particularly in image forming apparatuses such as display apparatuses, flat display apparatuses using liquid crystal have been increasingly used in CRTs.
However, since it is not a self-luminous type, there is a problem that a backlight must be provided, and the development of a self-luminous type display device has been desired. As the self-luminous display device, an image forming device (for example, an image forming device that is a display device combining an electron source having a large number of surface conduction electron-emitting devices and a phosphor that emits visible light by electrons emitted from the electron source) , USP 5,066,883).

Conventionally, in order to manufacture an image forming apparatus using these electron sources, a rear plate having an electron source in which a large number of surface conduction electron-emitting devices are arranged, and a face having a phosphor for emitting visible light. An image display device is formed by combining a plate with a support frame connected outside of the display unit and further with other components such as an exhaust pipe. Further, a spacer for connecting the substrates in the display unit to support the atmospheric pressure may be used. CRT,
Alternatively, the same frit glass as that used for assembly in another image forming apparatus or the like is generally used.

[0010] Conventionally, alteration of frit glass has caused various problems. In particular, there was a problem when PbO, which is a main component of the frit glass, was reduced to Pb. For example, a CRT causes dielectric breakdown. Another problem is that necessary connection strength cannot be generally obtained due to poor sealing.

The reduction of frit glass is caused by a reducing gas at a high temperature. For example, an organic gas for forming a face plate and a gas generated when a frit agent is thermally decomposed into a vehicle have become problems. For this reason, some measures have been taken to prevent the frit glass itself from being reduced even in these atmospheres. For example, there is a study of adding a powder additive to frit glass (Japanese Patent Publication No. 62-56095) and a study of a vehicle composition (Japanese Patent Publication No. 57-3613).

[0012]

SUMMARY OF THE INVENTION In the prior art, the main purpose is to prevent the reduction of frit glass. Therefore, no consideration is given to completely preventing the reducing gas generated during the thermal decomposition of the vehicle. When such a frit agent is assembled in an image forming apparatus using a surface conduction electron-emitting device as an electron beam source, the following problems may occur.

FIG. 21 shows an example of a conventional method for manufacturing an image forming apparatus using a surface conduction electron-emitting device. Substrate 1
An electron source substrate 81 on which an electron emission portion 5 is formed is manufactured by forming a matrix wiring and a conductive thin film 4 thereon, and further performing processing such as forming and activation.
4. Face plate 86 made of metal back 85 and the like
Is produced.

A portion (joining portion) where the spacer 89 of the rear plate 81 and the face plate 86, which are the electron source substrates, is arranged, and a portion where the support frame 82 is arranged,
Frit agent 1 which is a mixture of frit glass and vehicle
31 and 132 are applied respectively (see FIG. 21A). The frit glass is a powder, and the vehicle has a function of adjusting the viscosity to an appropriate value for application of the frit glass, and maintaining its shape up to the softening point of the frit glass. To that end, the vehicle comprises at least an organic binder and another solvent.

Thereafter, preheating may be performed,
This heating is called calcination. The vehicle is removed from the frit agents 131 and 132 by the pre-baking, and the frit glass is in a state of poor fluidity 133 and 134 (see FIG. 21B).

Thereafter, the spacer 89 and the support frame 82 are
It is aligned and heated to the sealing temperature of the frit glass. By this sealing, the rear plate 81 and the face plate 86 are connected to the spacer 89 and the support frame 82 via the glass frit 80, 90, thereby forming an envelope of the image forming apparatus (see FIG. 21C). ).

As described above, in the image forming apparatus formed by the conventional manufacturing method, the amount of electron emission from the element is sometimes small, and in the worst case, almost no image is displayed. This is considered to be because the electron-emitting portion was altered (deteriorated) during the preliminary firing. In order to prevent deterioration of the electron-emitting portion, a method of forming the conductive thin film, assembling it as an image forming apparatus, and then forming the electron-emitting portion by forming, activating, or the like is considered.

In this case, the resistance of the element becomes high, so that the normal forming process may not be performed. Also, even if the forming process is performed, the electron emission amount is generally small, and the image tends to be dark. This is considered to be due to the deterioration of the conductive thin film during the preliminary firing.

Further, in any case, a distribution occurs in the luminance of the display section, and the luminance tends to be darker in the peripheral portion than in the central portion, and the luminance around the spacer tends to be lower. Therefore, this distribution depends on the position of the frit agent, and it is presumed that the gas generated from the frit agent (organic binder) during the preliminary firing is the cause of the deterioration.
In the case of configuring an image forming apparatus having a larger area, not only the total amount of frit glass increases, but also a spacer in the display unit is required to secure the supporting strength as described above, and the element unit and the frit agent are not included. I have to get closer. Therefore, the vicinity of the spacer is more susceptible to the influence of the gas from the frit agent. Therefore, in the conventional method, it is difficult to form a high-luminance, uniform, large-area image forming apparatus using the surface conduction electron-emitting device as an electron beam source.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the prior art, and it is an object of the present invention to use a frit glass paste which does not affect an electron-emitting device, and to use a frit glass paste which is stable. An object of the present invention is to provide a display element having uniform electron emission characteristics, an image forming apparatus having the element, and a method of manufacturing the apparatus.

[0021]

The above objects and objects are solved and achieved by the present invention described below. That is, the present invention relates to a manufacturing method for assembling an image forming apparatus having an electron-emitting device via a glass frit, wherein the glass frit agent includes glass frit as a main component, inorganic fine particles as a thickener, a solvent or water. A method for manufacturing an image forming apparatus characterized by comprising:

In the method of manufacturing an image forming apparatus according to the present invention, the inorganic fine particles are mainly composed of silica fine particles obtained by a gas phase reaction, and the silica fine particles have a particle diameter of 1 to 100 nm. And the content of the silica fine particles is in the range of 1 to 50 wt% with respect to a solvent or water, and the electron-emitting device has a conductive property between opposing electrodes. It is a surface conduction electron-emitting device forming an electron-emitting portion made of a thin film, the conductive thin film is made of fine particles, and the conductive thin film is Pd or PdO. It is characterized by the following.

Further, the present invention provides an electron-emitting device obtained by the above-described manufacturing method, an image display device using the electron-emitting device, and using the image display device. An image forming apparatus is disclosed.

The image display apparatus using the frit glass paste provided by the present invention, which has been achieved to achieve the above object, is as follows. That is, in the present invention, viscosity is imparted by containing silica fine particles instead of the organic binder in the frit glass mixture.

The silica fine particles used in the present invention are desirably fine anhydrous silica fine particles produced by reacting a volatile compound containing silicon in the gas phase, and specific examples thereof include Nippon Aerosil under the trade name of AEROSIL. It has been released by the company. The following effects are expected by mixing the silica fine particles into the frit glass paste.

Conventionally, when a reducing gas, such as carbon monoxide or hydrogen, generated by burning and decomposing an organic binder when frit glass is fired, comes into contact, for example, at a temperature higher than the temperature at which the conductive thin film deteriorates, the resistance value changes. Or agglomeration. For this reason, an organic binder that does not generate a combustion decomposition gas such as the above-described reducing gas and has a thickening effect has been required.

According to the present invention, instead of the organic binder, silica fine particles having a particle size of 1 to 100 nm produced by a gas phase reaction are added to the frit glass powder in a proportion of several wt% to several tens wt% with respect to the solvent or water. The mixed material can be made into a paste by the thickening action of the silica fine particles, and can be applied to a predetermined position.

In addition, there is no need to decompose the binder as in the case of using an organic binder at the time of frit firing, and since no reducing gas is generated, no deterioration of the conductive thin film occurs, and forming defects and unevenness are avoided. be able to. In addition, since silica fine particles are used for bonding as a glass component, they exhibit good adhesive strength.

[0029]

Next, embodiments of the present invention will be specifically described. Hereinafter, first, a preferred embodiment of the frit glass component will be described. As a material of the frit glass powder, for example, a low melting point glass frit such as PbO—B ₂ O ₃ is used.
It is desirable that the sealing temperature is in the range of 400 to 550 ° C. The frit glass powder is used in the form of a paste with an appropriately adjusted viscosity in order to improve workability during application. At this time, as a thickener, a particle size of 1 to 100 nm
Use fine silica particles. The fine particle silica is preferably fine particle anhydrous silica produced by reacting a volatile compound containing silicon in the gas phase, and a specific example is sold by Nippon Aerosil Co. under the trade name of AEROSIL.

The Aerosil was first introduced in 1942 by Degussa
Developed by the company (Germany), produced by high-temperature hydrolysis of silicon tetrachloride in an oxyhydrogen flame. This feature has a very high purity, the particles are almost completely spherical and uniform in particle size, have less cohesiveness, a lower bulk density,
Good dispersibility. In addition, the thickening effect of the liquid is large, and FIG. 16 shows the thickening effect of Aerosil in various liquids. FIG. 17 shows a particle size distribution diagram (electron micrograph) of a typical AEROSIL 200 and a primary particle size distribution curve.

The thickening effect of Aerosil can be explained as follows. When Aerosil is dispersed in a liquid, the silanol groups on the solid surface begin to interact directly or indirectly with the liquid molecules. This affinity is due to hydrogen cross-linking, which temporarily results in a three-dimensional network that is visible to the naked eye as a thickening effect. When a mechanical load is applied by agitation or vibration, the mesh is broken again, and the viscosity of the system is reduced. However, when the applied force is removed, the network is regenerated in a short time and the viscosity is increased again. . This process is called thixotropy (see FIG. 15).

As is clear from FIG. 16, the thickening and thixotropic effects of Aerosil depend on the polarity of the system. In that case, the best results are obtained in a rather non-polar system. Polarity here is to be understood as the possibility that liquid molecules can form hydrogen cross-links.
In order to adjust the rheology of strongly polar substances such as water and dimethylformamide, it has been proven that a mixed system with aluminum oxide fine particles is good.

The use of a non-polar or weakly polar solvent as a solvent for dispersing the same provides a greater thickening effect. Solvents having a high boiling point may remain even after drying, and may decompose similarly to the organic binder to generate a reducing gas. If the boiling point is about 200 ° C. or less, it can be volatilized and used. Specific examples include methyl acetate, carbon tetrachloride, chloroform, chlorobenzene, n-hexanol and the like.

Of the below-described materials constituting the conductive thin film, for example, a thin film composed of Pd fine particles is 60 in vacuum.
It has been confirmed that although hydrogen does not coagulate even at 0 ° C., it coagulates at about 350 ° C. in the presence of hydrogen. Also, carbon monoxide is expected to have a function similar to hydrogen.

It is known that when a polar solvent such as water or ethanol is used, a large thickening effect (see FIG. 18) can be obtained by using a mixture of silica fine particles and aluminum oxide fine particles. The mixing ratio with respect to the solvent and water varies depending on the desired viscosity.
%, Preferably 1 to 10% by weight.

The frit glass paste after application is 12
Dry at about 0 ° C to remove solvent or water. At this time,
The three-dimensional network structure of the silica fine particles formed as shown in FIG. 15 can maintain its shape without being destroyed even after the solvent or water evaporates. Next, it is fired at a sealing temperature of 400 to 550 ° C. to obtain a frit glass fired body to obtain a fixed medium such as a spacer.

Second, a preferred embodiment of an image forming apparatus using the frit will be described. First, an electron source used in the present invention will be described. The cold cathode electron source used in the present invention has a simple configuration, and a surface conduction electron-emitting device that is easy to manufacture is suitable. Hereinafter, the present invention will be described with reference to the drawings. FIG. 1 is a schematic view showing one example of the surface conduction electron-emitting device of the present invention.

FIG. 1 is a schematic view showing the structure of a flat surface conduction electron-emitting device to which the present invention can be applied.
1A is a plan view, and FIG. 1B is a cross-sectional view. In FIG. 1, 1 is a substrate, 2 and 3 are device electrodes, 4 is a conductive thin film, 5
Denotes an electron emission portion.

Examples of the substrate 1 include quartz glass, glass having a reduced impurity content such as Na, blue plate glass, a glass substrate obtained by laminating SiO ₂ on a blue plate glass by sputtering or the like, ceramics such as alumina, and Si substrate. Can be used.

An offset printing method is suitable for forming the opposing element electrodes 2 and 3 because the transfer film thickness of the ink can be reduced and high-definition printing can be performed. A resinate paste made of an organic metal is used as a material for printing the electrodes, and examples of the metal material include metals or alloys such as Ni, Cr, Au, Mo, W, Pt, Ti, Al, Uu, and Pd. Pd, Au, Ru
It can be appropriately selected from a printed conductor composed of a metal such as O ₂ or Pd-Ag or a metal oxide and glass.

The element electrode interval L, the element electrode length W, the shape of the conductive thin film 4, and the like are designed in consideration of the applied form and the like. The element electrode interval L can be in the range of several tens to several hundreds μm, and preferably in the range of several μm to several tens μm in consideration of the voltage applied between the element electrodes. The length W of the device electrode 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 thickness d of the device electrodes 2 and 3 can be in the range of several tens to several μm. Further, the wiring connected to the pair of electrodes can be formed by a screen printing method.

As the conductive thin film 4, a fine particle film composed of fine particles is preferably used in order to obtain good electron emission characteristics. The film thickness is appropriately set in consideration of the step coverage of the device electrodes 2 and 3, the resistance value between the device electrodes 2 and 3, a forming condition described later, and the like. The range is preferably 100 nm, more preferably 1 nm to 50 nm. The resistance value is such that Rs is 10 ² to 10 ⁷ Ω / □. Note that Rs appears when the resistance R of a thin film having a thickness t, a width w, and a length 1 is represented by R = Rs (l / w). Here, the forming process will be described by taking an energizing process as an example, but the forming process is not limited to this, and includes a process of forming a crack in the film to form a high resistance state. .

The material constituting the conductive thin film 4 is Pd, Pt,
Ru, Ag, Au, Ti, In, Uu, Cr, Fe, Zn, Sn, Ta, W, Pb
Metal _{etc., PdO, SnO 2, In 2} O 3, PdO, oxides such as _{Sb 2 O 3, HfB 2,} ZrB 2, LaB 6 .CeB 6, YB 4, GdB borides such as _4, TiC, ZrC , HfC, TaC, SiC, WC and the like, nitrides such as TiN, ZrN and HfN, semiconductors such as Si and Ge, carbon and the like.

The fine particle film described here is a film in which a plurality of fine particles are aggregated, and has a fine structure in a state where the fine particles are individually dispersed and arranged or in a state where the fine particles are adjacent to each other or overlap each other (when some fine particles are formed). To form an island-like structure as a whole). The particle size of the fine particles is in the range of several times 0.1 nm to several hundred nm, preferably in the range of 1 to 20 nm.

Hereinafter, the term “fine particles” is frequently used, and its meaning will be described. Small particles are called "fine particles" and smaller ones are called "ultra fine particles". It is widely practiced to call a “cluster” smaller than “ultrafine particles” and having a few hundred atoms or less.

However, each boundary is not strict and changes depending on what kind of property is focused on. In addition, “fine particles” and “ultrafine particles” may be collectively referred to as “fine particles”, and the description herein is in line with this.

The following is described in “Experimental Physics Course 14 Surface / Particles” (edited by Kinoshita Yoshio, published by Kyoritsu Shuppan, September 1, 1986).

"In the present case, the particle diameter is about 2 to 3 μm to about 10 nm in the case of fine particles, and the particle diameter is about 10 nm to 2 to 10 nm especially in the case of ultrafine particles.
It means up to about 3 nm. The two are collectively simply written as fine particles, so they are not strictly accurate, but are approximate. When the number of atoms constituting a particle is two to several tens to several hundreds, it is called a cluster. (Pp. 195, lines 22-26).

In addition, the definition of “ultrafine particles” in the New Technology Development Corporation “Hayashi / Ultrafine Particle Project” is as follows, with the lower limit of the particle size being smaller. "Creative Science and Technology Promotion System" Ultra Fine Particle Project "(198
1 to 1986), the size (diameter) of the particles is approximately 1 to 1
Ultra-fine particles in the range of 100 nm (utlra fine pa
rticle). Then, one ultrafine particle is an aggregate of about 100 to 108 atoms. Ultra-fine particles are large to giant particles on an atomic scale. ("Ultra Fine Particles and Creative Science and Technology" Hayashi Tax, Ryoji Ueda, Akira Tazaki, ed., Mita Publishing, 1988, page 2, lines 1 to 4)
"A particle smaller than an ultrafine particle, that is, a single particle composed of several to several hundred atoms is usually called a cluster" (p. 2, lines 12 to 13).

[0050] Based on the general notation as described above,
In the present specification, “ultrafine particles” refers to an aggregate of a large number of atoms and molecules, and the lower limit of the particle size is several times to 0.1 nm to about 1 nm, and the upper limit is about several μm.

The electron-emitting portion 5 is constituted by a high-resistance crack formed in a part of the conductive thin film 4 and depends on the thickness, film quality, material, and a method such as energization forming described later of the conductive thin film 4. It will be. In some cases, conductive fine particles having a particle size in the range of several times 0.1 nm to several tens nm are present inside the electron emitting portion 5. The conductive fine particles contain some or all of the elements of the material constituting the conductive thin film 4. The electron emitting portion 5 and the conductive thin film 4 in the vicinity thereof can also contain carbon and a carbon compound.

Hereinafter, an example of the manufacturing method will be described with reference to FIGS. 2, the same parts as those shown in FIG. 1 are denoted by the same reference numerals as those shown in FIG.

(1) After sufficiently washing the substrate 1 with a detergent, pure water, an organic solvent, or the like, a resinate paste made of an organic metal is printed and baked by offset printing, and the device electrodes 2, 3 are formed on the substrate 1. Is formed (see FIG. 2A).
In addition, the element electrode is not limited to the offset printing method, and is appropriately selected.

(2) On the substrate 1 provided with the device electrodes 2 and 3,
Application of organometallic solution by inkjet method (Fig. 2
(See (b)) to form an organometallic thin film. As the organic metal solution, a solution of an organic metal compound containing the metal of the material of the conductive film 4 as a main element can be used. Particularly, a solution mainly composed of these aqueous solutions is desirable. This organic metal thin film is heated and baked at 200 to 500 ° C. to form a conductive thin film 4 (see FIG. 2C).

Although the description has been given here of the application method of the organic metal solution by the ink jet method, the present invention is not limited to this. The vacuum evaporation method, the sputtering method, the chemical vapor deposition method, the dispersion coating method, the dipping method, and the like. It may be formed by a spinner method or the like.

(3) Subsequently, a forming step is performed.
As an example of this forming step method, a method by an energization process will be described. When power is applied between the device electrodes 2 and 3 using a power supply (not shown), an electron-emitting portion 5 having a changed structure is formed at a portion of the conductive thin film 4 (see FIG. 2D). According to the energization forming, a portion where the structure such as destruction, deformation or alteration is locally formed in the conductive thin film 4 is formed. The portion becomes the electron emission portion 5. FIG. 3 shows an example of the voltage waveform of the energization forming.

The voltage waveform is preferably a pulse waveform. The method shown in FIG. 3A in which a pulse having a pulse peak value of a constant voltage is continuously applied and the method shown in FIG. 3B in which a voltage pulse is applied while increasing the pulse peak value are applied. There is.

T1 and T2 in FIG. 3A are the pulse width and pulse interval of the voltage waveform. Normally T1 is 1μ
Seconds to 10 ms, and T2 is set in the range of 10 μs to 100 ms. The peak value of the triangular wave (peak voltage at the time of energization forming) is appropriately selected according to the surface conduction electron-emitting device. Under such conditions, for example, a voltage is applied for several seconds to several tens minutes. The pulse waveform is not limited to a triangular wave, and a desired waveform such as a rectangular wave can be adopted.

T1 and T2 in FIG. 3B can be the same as those shown in FIG. The peak value of the triangular wave (peak voltage during energization forming) can be increased by, for example, about 0.1 V steps.
The end of the energization forming process is performed during the pulse interval T2.
By applying a voltage that does not locally destroy or deform the conductive thin film 4, the current can be measured and detected. For example, when a device current flowing by applying a voltage of about 0.1 V is measured and a resistance value is obtained, and a resistance of 1 MΩ or more is indicated,
The energization forming is terminated.

(4) It is preferable to perform a process called an activation step on the element after the forming. The activation step is a step in which the element current If and the emission current Ie are significantly changed by this step. The activation step can be performed, for example, by repeatedly applying a pulse in an atmosphere containing an organic substance gas, similarly to the energization forming. This atmosphere can be formed using an organic gas remaining in the atmosphere when the inside of the vacuum vessel is evacuated using, for example, an oil diffusion pump or a rotary pump,
It can also be obtained by introducing a gas of an appropriate organic substance into a vacuum once sufficiently evacuated by an ion pump or the like.
The preferable gas pressure of the organic substance at this time varies depending on the above-described application form, the shape of the vacuum vessel, the type of the organic substance, and the like, and is appropriately set according to the case.

Examples of suitable organic substances are alkanes,
Alkenes, aliphatic hydrocarbons of alkynes, aromatic hydrocarbons, alcohols, aldehydes, ketones, amines, phenols, carboxyls, organic acids such as sulfonic acids and the like, and specifically, Saturated hydrocarbons represented by C _n H _{2n + 2} such as methane, ethane and propane; unsaturated hydrocarbons represented by a composition formula such as C _n H _2n such as ethylene and propylene; benzene, toluene, methanol, ethanol and formaldehyde , Acetaldehyde, acetone,
Methyl ethyl ketone, methylamine, ethylamine, phenol, formic acid, acetic acid, propionic acid and the like can be used.

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. The end of the activation step is determined as appropriate while measuring the device current If and the emission current Ie. The pulse width, pulse interval, pulse crest value, and the like are set as appropriate.

Carbon and carbon compounds include, for example, graphite (including so-called HOPG, PG (GC),
HOPG has a nearly perfect graphite crystal structure, PG has a crystal grain of about 20 nm and has a slightly disordered crystal structure, GC
Are amorphous carbon (refer to amorphous carbon and a mixture of amorphous carbon and the above-mentioned graphite microcrystal), and the film thickness thereof is about 2 nm, and the disorder of the crystal structure is further increased. 50
nm or less, and more preferably 30 nm or less.

(5) The electron-emitting device obtained through such a step is preferably subjected to a stabilization step. This step is a step of exhausting the organic substance in the vacuum vessel. 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. Specifically, a vacuum exhaust device such as a sorption pump and an ion pump can be used.

In the activation step, when an oil diffusion pump or a rotary pump is used as an exhaust device and an organic gas derived from an oil component generated from the oil diffusion pump or the rotary pump is used, the partial pressure of this component needs to be kept as low as possible. . The partial pressure of the organic component in the vacuum vessel is preferably 1.3 × 10 ⁻⁶ Pa or less, more preferably 1.3 × 10 ⁻⁸ Pa or less, at which the above-mentioned carbon and carbon compounds hardly newly deposit. Particularly preferred.
Further, when evacuating the inside of the vacuum vessel, it is preferable to heat the entire vacuum vessel to facilitate evacuating the organic substance molecules adsorbed on the inner wall of the vacuum vessel and the electron-emitting device. The heating conditions at this time are desirably 5 hours or more at 80 to 200 ° C., but are not particularly limited to these conditions, and are appropriately selected according to various conditions such as the size and shape of the vacuum vessel and the configuration of the electron-emitting device. Do. The pressure in the vacuum vessel needs to be as low as possible, and is preferably 1.3 to 3.9 × 10 ⁻⁵ Pa or less, more preferably 1.3 × 10 ⁻⁶ Pa or less.
After performing the stabilization step in place of the organic binder, the atmosphere during driving is preferably to maintain the atmosphere at the time of completion of the stabilization treatment, but is not limited thereto, and the organic substance is sufficiently removed. In this case, even if the degree of vacuum itself is slightly reduced, it is possible to maintain sufficiently stable characteristics. By adopting such a vacuum atmosphere, the deposition of new carbon or carbon compound can be suppressed, and as a result, the device current I
f, the emission current Ie is stabilized.

The basic characteristics of the electron-emitting device to which the present invention can be applied obtained through the above-described steps will be described with reference to FIGS. FIG. 4 is a schematic view showing an example of a vacuum processing apparatus, and this vacuum processing apparatus also has a function as a measurement evaluation apparatus. 4, the same parts as those shown in FIG. 1 are denoted by the same reference numerals as those shown in FIG. In FIG. 4, reference numeral 65 denotes a vacuum vessel, and 66 denotes an exhaust pump.

An electron-emitting device is provided in the vacuum vessel 65. That is, 1 is a base constituting an electron-emitting device, 2 and 3 are device electrodes, 4 is a conductive thin film, and 5 is an electron-emitting portion. Reference numeral 61 denotes a device voltage Vf applied to the electron-emitting device.
, A current meter 60 for measuring a device current If flowing through the conductive thin film 4 between the device electrodes 2 and 3, and a emission current I 64 emitted from an electron emission portion of the device.
This is an anode electrode for capturing e. 63 is a high-voltage power supply for applying a voltage to the anode electrode 64, and 62 is an ammeter for measuring the emission current Ie emitted from the electron emission section 5 of the device. As an example, the measurement can be performed with the voltage of the anode electrode in the range of 1 to 10 kV and the distance H between the anode electrode and the electron-emitting device in the range of 2 to 8 mm.

The vacuum vessel 65 is provided with equipment required for measurement in a vacuum atmosphere, such as a vacuum gauge (not shown), so that measurement and evaluation in a desired vacuum atmosphere can be performed. . The exhaust pump 66 is composed of a normal high vacuum device system including a turbo pump and a rotary pump, and an ultra-high vacuum device system including an ion pump and the like. The entire vacuum processing apparatus provided with the electron source substrate shown here can be heated to 200 ° C. by a heater (not shown). Therefore, by using this vacuum processing apparatus, the steps after the above-described energization forming can also be performed.

FIG. 5 shows the emission current Ie, the device current If, and the device voltage V measured using the vacuum processing apparatus shown in FIG.
It is the figure which showed the relationship of f typically. In FIG.
Since the emission current Ie is significantly smaller than the element current If, it is shown in arbitrary units. The vertical and horizontal axes are linear scales. As apparent from FIG. 5, the surface conduction electron-emitting device to which the present invention can be applied has three characteristic properties with respect to the emission current Ie.

(I) When an element voltage of a certain voltage (referred to as a threshold voltage, Vth in FIG. 5) or more is applied to the present element, the emission current Ie sharply increases, and on the other hand, the threshold voltage Vth or less. In this case, the emission current Ie is hardly detected.
That is, a clear threshold voltage Vt for the emission current Ie
h is a non-linear element. (ii) Since the emission current Ie depends monotonically on the device voltage Vf, the emission current Ie can be controlled by the device voltage Vf. (iii) The emission charge captured by the anode electrode 64 depends on the time during which the device voltage Vf is applied. That is, the amount of charge captured by the anode electrode 64 can be controlled by the time during which the device voltage Vf is applied.

As understood from the above description, the surface conduction type electron-emitting device to which the present invention can be applied can easily control the electron emission characteristics according to the input signal.
If this property is used, it can be applied to various fields such as an electron source and an image forming apparatus having a plurality of electron-emitting devices.

FIG. 5 shows an example in which the element current If monotonically increases with respect to the element voltage Vf (hereinafter referred to as MI characteristic). In some cases, the element current If indicates a voltage-controlled negative resistance characteristic (hereinafter, referred to as VCNR characteristic) with respect to the element voltage Vf (not shown). These characteristics can be controlled by controlling the aforementioned steps.

An application example of the electron-emitting device to which the present invention can be applied will be described below. By arranging a plurality of surface conduction electron-emitting devices to which the present invention is applicable on a substrate, for example, an electron source or an image forming apparatus can be configured.

Various arrangements of the electron-emitting devices can be adopted. As an example, each of a large number of electron-emitting devices arranged in parallel is connected at both ends, a large number of rows of electron-emitting devices are arranged (referred to as a row direction), and a direction perpendicular to the wiring (referred to as a column direction). There is a ladder-like arrangement in which electrons from the electron-emitting devices are controlled and driven by control electrodes (also referred to as grids) disposed above the electron-emitting devices. Separately, a plurality of electron-emitting devices are arranged in rows and columns in the X and Y directions, and one of the electrodes of the plurality of electron-emitting devices arranged in the same row is commonly connected to a wiring in the X direction. One example is one in which the other of the electrodes of a plurality of electron-emitting devices arranged in the same column is commonly connected to a wiring in the Y direction. This is a so-called simple matrix arrangement. First, the simple matrix arrangement will be described in detail below.

The surface conduction electron-emitting device to which the present invention can be applied has the above-mentioned characteristics (i) to (iii) as described above. That is, when the electron emission from the surface conduction electron-emitting device is equal to or higher than the threshold voltage, it can be controlled by the peak value and the width of the pulse voltage applied between the opposing device electrodes. On the other hand, when the voltage is equal to or lower than the threshold voltage, almost no light is emitted. According to this characteristic, even when a large number of electron-emitting devices are arranged, if a pulse-like voltage is appropriately applied to each of the devices, a surface-conduction electron-emitting device is selected according to an input signal to emit electrons. You can control the amount.

Hereinafter, an electron source substrate obtained by disposing a plurality of electron-emitting devices to which the present invention can be applied based on this principle will be described with reference to FIG. In FIG. 6, reference numeral 81 denotes an electron source substrate, 82 denotes an X-direction wiring, and 83 denotes a Y-direction wiring.
84 is a surface conduction electron-emitting device, and 85 is a connection. The surface conduction electron-emitting device 84 may be of the above-mentioned flat type or vertical type.

The m X-direction wirings 82 are Dx1, Dx2,
.., Dxm, and can be made of a conductive metal or the like formed by a vacuum deposition method, a printing method, a sputtering method, or the like. The material, thickness, and width of the wiring are appropriately designed.
The Y-direction wiring 83 is composed of n wirings Dy1, Dy2,..., Dyn, and is formed in the same manner as the X-direction wiring 82. An interlayer insulating layer (not shown) is provided between the m X-directional wirings 82 and the n Y-directional wirings 83, and electrically separates them (m and n are both common). Positive integer).

The interlayer insulating layer (not shown) is made of SiO ₂ or the like formed by using a vacuum deposition method, a printing method, a sputtering method, or the like. For example, the film 81 is formed in a desired shape on the entire surface or a part of the substrate 81 on which the X-directional wiring 82 is formed. The production method is appropriately set. The X-direction wiring 82 and the Y-direction wiring 83 are led out as external terminals.

A pair of electrodes (not shown) constituting the surface conduction electron-emitting device 84 are electrically connected to m X-directional wires 82 and n Y-directional wires 83 by a connection 85 made of a conductive metal or the like. Have been. Some or all of the constituent elements of the material forming the wiring 82 and the wiring 83, the material forming the connection 85, and the material forming the pair of element electrodes may be the same or different. These materials are appropriately selected, for example, from the above-described materials for the device electrodes. When the material forming the element electrode is the same as the wiring material, the wiring connected to the element electrode can also be called an element electrode.

The X-direction wiring 82 is connected to a scanning signal applying means (not shown) for applying a scanning signal for selecting a row of the surface conduction electron-emitting devices 84 arranged in the X direction. On the other hand, a modulation signal generating means (not shown) for modulating each column of the surface conduction emission devices 84 arranged in the Y direction according to an input signal is connected to the Y direction wiring 83. The driving voltage applied to each electron-emitting device is supplied as a difference voltage between a scanning signal and a modulation signal applied to the device. In the above configuration, individual elements can be selected and driven independently using simple matrix wiring.

An image forming apparatus constructed using such an electron source having a simple matrix arrangement will be described with reference to FIGS. 7, 8 and 9. FIG. 7 is a schematic diagram illustrating an example of a display panel of the image forming apparatus, and FIG. 8 is a schematic diagram of a fluorescent film used in the image forming apparatus of FIG. FIG. 9 shows NT
It is a block diagram which shows an example of the drive circuit for performing a display according to a television signal of SC system.

In FIG. 7, reference numeral 81 denotes an electron source substrate on which a plurality of electron-emitting devices are arranged; 91, a rear plate on which the electron source substrate 81 is fixed; 96, a fluorescent film 94 on the inner surface of a glass substrate 93;
And a face plate on which a metal back 95 and the like are formed. Reference numeral 92 denotes a support frame, and a rear plate 91 and a face plate 96 are connected to the support frame 92 using frit glass or the like. Reference numeral 98 denotes an envelope, which is sealed, for example, by firing in air or nitrogen at a temperature range of 400 to 500 ° C. for 10 minutes or more. 84
Corresponds to the electron emission section 5 in FIG. 82,83
Are X-direction wiring and Y-direction wiring connected to a pair of device electrodes of the surface conduction electron-emitting device.

The envelope 98 includes the face plate 96, the support frame 92, and the rear plate 91 as described above. Since the rear plate 91 is provided mainly for the purpose of reinforcing the strength of the substrate 81, if the substrate 81 itself has sufficient strength, the separate rear plate 91 can be unnecessary. That is, the support frame 92 is directly sealed to the substrate 81,
The envelope 98 may be constituted by the face plate 96, the support frame 92, and the substrate 81. On the other hand, face plate 9
6. By installing a support (not shown) called a spacer between the rear plates 91, an envelope 98 having sufficient strength against atmospheric pressure can be formed.

FIG. 8 is a schematic diagram showing a fluorescent film. The fluorescent film 94 can be composed of only a phosphor in the case of monochrome. In the case of a color fluorescent film, it can be composed of a black conductive material 101 called a black stripe or a black matrix and a fluorescent material 102 depending on the arrangement of the fluorescent materials. The purpose of providing the black stripes and the black matrix is to make the mixed portions inconspicuous by making the painted portions between the phosphors 102 of the necessary three primary color phosphors black in the case of color display,
In suppressing a decrease in contrast due to reflection of external light. As the material of the black stripe, a material having conductivity and having little light transmission and reflection can be used in addition to a material mainly containing graphite which is generally used.

The method of applying the fluorescent substance on the glass substrate 93 can employ a precipitation method, a printing method or the like irrespective of monochrome or color. Usually, a metal back 95 is provided on the inner surface side of the fluorescent film 94. The purpose of providing a metal back is
Light emitted to the inner surface side of the light emitted from the phosphor is transferred to the face plate 9.
Improve the brightness by specular reflection on the 6 side, act as an electrode for applying electron beam acceleration voltage, protect the phosphor from damage due to collision of negative ions generated in the envelope, etc. It is. The metal back can be produced by performing a smoothing treatment (usually called filming) on the inner surface of the phosphor film after producing the phosphor film, and then depositing Al by vacuum deposition or the like.

The face plate 96 may be provided with a transparent electrode (not shown) on the outer surface of the fluorescent film 94 in order to further increase the conductivity of the fluorescent film 94. When performing the above-described sealing, in the case of color, it is necessary to make each color phosphor correspond to the electron-emitting device, and sufficient alignment is indispensable.
The image forming apparatus shown in FIG. 7 is manufactured, for example, as follows.

The envelope 98 is evacuated through an exhaust pipe (not shown) by an exhaust device that does not use oil, such as an ion pump and a sorption pump, while appropriately heating, as in the above-described stabilization process. Sealing is performed after setting the atmosphere of a vacuum degree of about ^10-5 Pa to a sufficiently low level of the organic substance. In order to maintain the degree of vacuum after sealing the envelope 98, a getter process may be performed. This is because the getter arranged at a predetermined position (not shown) in the envelope 98 is heated by heating using resistance heating or high-frequency heating immediately before or after the envelope 98 is sealed. This is a process for forming a deposited film. The getter is usually composed mainly of Ba or the like.
The pressure is maintained at 0 ^-3 or 1.3 × 10 ^-5 Pa. Here, steps after the forming process of the surface conduction electron-emitting device can be appropriately set.

Next, an example of the configuration of a drive circuit for performing television display based on NTSC television signals on a display panel configured using electron sources in a simple matrix arrangement will be described with reference to FIG. . In FIG. 9, 1
Reference numeral 11 denotes an image display panel, 112 denotes a scanning circuit, 113 denotes a control circuit, and 114 denotes a shift register. 115 is a line memory, 116 is a synchronization signal separation circuit, 117 is a modulation signal generator, and Vx and Va are DC voltage sources.

The display panel 111 has terminals Dox1 to Do
xm, terminals Doy1 to Doyn, and a high voltage terminal Hv are connected to an external electric circuit. Terminal Dox1
Doxm has an electron source provided in the display panel,
That is, a scanning signal is applied to sequentially drive the surface conduction electron-emitting device groups arranged in a matrix of M rows and N columns, one row at a time (N elements).

A modulation signal for controlling an output electron beam of each of the surface conduction electron-emitting devices in one row selected by the scanning signal is applied to the terminals Dy1 to Dyn. The high-voltage terminal Hv is connected to the DC voltage source Va, for example, by one.
A DC voltage of 0 K [V] is supplied, which is an accelerating voltage for applying sufficient energy to the electron beam emitted from the surface conduction electron-emitting device to excite the phosphor.

Next, the scanning circuit 112 will be described. This circuit includes M switching elements inside (in the figure, S1 to Sm are schematically shown). Each switching element is connected to the output voltage of the DC voltage source Vx or 0
[V] (ground level) is selected and electrically connected to the terminals Dx1 to Dxm of the display panel 111. Each of the switching elements S1 to Sm operates based on the control signal Tscan output from the control circuit 113, and can be configured by combining switching elements such as FETs, for example.

In the case of the present embodiment, the DC voltage source Vx uses a drive voltage applied to an unscanned element based on the characteristics (electron emission threshold voltage) of the surface conduction type electron emission element. It is set to output a constant voltage that is equal to or lower than the voltage.

The control circuit 113 has a function of matching the operation of each unit so that appropriate display is performed based on an image signal input from the outside. The control circuit 113 generates control signals Tscan, Tsft, and Tmry for each unit based on the synchronization signal Tsync sent from the synchronization signal separation circuit 116.

The synchronizing signal separating circuit 116 is a circuit for separating a synchronizing signal component and a luminance signal component from an NTSC television signal input from the outside, and uses a general frequency separating (filter) circuit or the like. Can be configured. The synchronizing signal separated by the synchronizing signal separating circuit 116 includes a vertical synchronizing signal and a horizontal synchronizing signal, but is shown here as a Tsync signal for convenience of explanation. The luminance signal component of the image separated from the television signal is referred to as a DATA signal for convenience. The DATA signal is input to the shift register 114.

The shift register 114 is for serially / parallel converting the DATA signal input serially in time series for each line of an image, and is based on a control signal Tsft sent from the control circuit 113. Works. (That is, it can be said that the control signal Tsft is a shift clock of the shift register 114). The data for one line of the serial / parallel-converted image (corresponding to drive data for N electron-emitting devices) is output from the shift register 114 as N parallel signals Idl to Idn.

The line memory 115 is a storage device for storing data for one line of an image for a required time, and stores the contents of Idl to Idn as appropriate according to a control signal Tmry sent from the control circuit 113. The stored contents are output as I'dl to I'dn and input to the modulation signal generator 117.

The modulation signal generator 117 outputs the image data I '
dl to I'dn are signal sources for appropriately driving and modulating each of the surface conduction electron-emitting devices in accordance with each of dl to I'dn. Applied to the emitting element.

As described above, the electron-emitting device to which the present invention can be applied has the following basic characteristics with respect to the emission current Ie. That is, electron emission has a clear threshold voltage Vth, 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. Therefore, when a pulse-like voltage is applied to the device, for example, when a voltage lower than the electron emission threshold is applied, electron emission does not occur, but when a voltage higher than the electron emission threshold is applied. Outputs an electron beam. that time,
The intensity of the output electron beam can be controlled by changing the peak value Vm of the pulse. In addition, it is possible to control the total amount of charges of the output electron beam by changing the pulse width Pw.

Therefore, as a method of modulating the electron-emitting device according to the input signal, a voltage modulation method, a pulse width modulation method, or the like can be employed. When implementing the voltage modulation method, a circuit of a voltage modulation method that generates a voltage pulse of a fixed length and modulates the peak value of the pulse appropriately according to input data is used as the modulation signal generator 117. be able to.

When implementing the pulse width modulation method,
As the modulation signal generator 117, a pulse width modulation type circuit that generates a voltage pulse having a constant peak value and appropriately modulates the width of the voltage pulse according to input data can be used.

The shift register 114 and the line memory 11
5 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.

When the digital signal type is used, it is necessary to convert the output signal DATA of the synchronizing signal separating circuit 116 into a digital signal. For this purpose, an A / D converter may be provided at the output section of the 116. In connection with this, the line memory 11
Depending on whether the output signal of 5 is a digital signal or an analog signal,
The circuit used for modulation signal generator 117 is slightly different. That is, in the case of the voltage modulation method using a digital signal, the modulation signal generator 117 includes, for example, D / A
A conversion circuit is used, and an amplification circuit and the like are added as necessary.
In the case of the pulse width modulation method, the modulation signal generator 117 includes:
For example, a circuit combining a high-speed oscillator, a counter (counter) for counting the number of waves output from the oscillator, and a comparator (comparator) for comparing the output value of the counter with the output value of the memory is used. If necessary, an amplifier for amplifying the voltage of the pulse width modulated signal output from the comparator to the drive voltage of the surface conduction electron-emitting device can be added.

In the case of the voltage modulation method using an analog signal, for example, an amplification circuit using an operational amplifier or the like can be used as the modulation signal generator 117, and a level shift circuit or the like can be added as necessary. In the case of the pulse width modulation method, for example, a voltage-controlled oscillation circuit (VCO) can be employed, and an amplifier for amplifying the voltage up to the drive voltage of the surface conduction electron-emitting device can be added as necessary.

In the image display device to which the present invention can be applied, which has such a configuration, by applying a voltage to each electron-emitting device via the external container terminals Dox1 to Doxm and Doy1 to Doyn, the electron-emitting device can emit electrons. Occurs. A high voltage is applied to the metal back 95 or a transparent electrode (not shown) via the high voltage terminal Hv to accelerate the electron beam. The accelerated electrons collide with the fluorescent film 94 and emit light to form an image.

The configuration of the image forming apparatus described here is an example of an image forming apparatus to which the present invention can be applied, and various modifications can be made based on the technical idea of the present invention. For the input signal, the NTSC system has been described, but the input signal is not limited to this, and in addition to the PAL, SECAM system, etc.
A TV signal composed of a large number of scanning lines (for example,
A high-definition TV system such as the MUSE system can also be adopted.

Next, a ladder-type arrangement of the electron source and the image display device will be described with reference to FIGS. 10 and 11. FIG.
FIG. 10 is a schematic diagram illustrating an example of an electron source having a ladder-type arrangement. In FIG. 10, reference numeral 120 denotes an electron source substrate, and 121 denotes an electron-emitting device. 122, Dx1 to Dx10 are common wirings for connecting to the electron-emitting device 121. A plurality of electron-emitting devices 121 are arranged in parallel in the X direction on the substrate 120 (this is called an element row). A plurality of the element rows are arranged to constitute an electron source. By applying a drive voltage between the common wires 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 an element row that wants to emit an electron beam, and a voltage equal to or lower than the electron emission threshold is applied to an element row that does not emit an electron beam. Common wiring Dx between each element row
2 to Dx9, for example, Dx2 and Dx3 can be the same wiring.

FIG. 11 is a schematic view showing an example of a panel structure in an image forming apparatus having a ladder-type electron source. 130 is a grid electrode, 131 is a hole through which electrons pass, and 132 is Dox1, Dox2,.
oxm. Reference numeral 133 denotes an external terminal composed of G1, G2,..., Gn connected to the grid electrode 120, and reference numeral 134 denotes an electron source substrate in which the common wiring between the element rows is the same.

In FIG. 11, the same parts as those shown in FIGS. 7 and 10 are denoted 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 the simple matrix arrangement shown in FIG. 7 is that the electron source substrate 120 (or 81) and the face plate 9
6 whether or not the grid electrode 130 is provided.

In FIG. 11, a grid electrode 130 is provided between the substrate 120 and the face plate 96. The grid electrode 130 modulates the electron beam emitted from the surface conduction electron-emitting device. In order to allow the electron beam to pass through a stripe-shaped electrode provided orthogonal to the ladder-shaped arrangement element row, A circular opening 131 is provided one by one corresponding to the element. The shape and installation position of the grid are not limited to those shown in FIG. For example, a large number of passage openings may be provided in the form of a mesh as openings, and a grid may be provided around or near the surface conduction electron-emitting device. The outer container terminal 132 and the outer grid container terminal 133 are electrically connected to a control circuit (not shown).

In the image forming apparatus of this embodiment, a modulation signal for one line of an image is simultaneously applied to the grid electrode rows in synchronization with sequentially driving (scanning) the element rows one by one. This makes it possible to control the irradiation of each electron beam to the phosphor and display an image one line at a time. The image forming apparatus of the present invention can be used as an image forming apparatus as an optical printer configured using a photosensitive drum or the like, in addition to a display device for television broadcasting, a display device for a video conference system, a computer, and the like. it can.

[0111]

EXAMPLES The present invention will be described in detail below with reference to specific examples, but the present invention is not limited to these examples, and each element within a range in which the object of the present invention is achieved. This also includes those in which substitutions or design changes have been made.

[Example 1] In Example 1, as the frit glass powder, PbO having the same component as LS-3081 which is a commercially available low melting point frit glass manufactured by NEC Corporation was used.
A frit glass powder containing -B ₂ O ₃ as a main component and a filler were used. Its softening point is 362 ° C. AEROSIL20 manufactured by Nippon Aerosil Co., Ltd.
0 (average particle diameter of primary particles is about 12 nm) was mixed and dispersed in methyl acetate at 10 wt%, and mixed with frit glass powder to obtain a frit glass paste. At this time, 5 parts of frit glass powder were added to AEROSIL20.
0 was 1 part by weight. The viscosity at this time is about 10
000 mPas.

A method for manufacturing an image forming apparatus using the frit pace will be described below. As the electron-emitting device, an electron-emitting device of the type shown in FIGS. 1A and 1B was prepared. FIG. 1A is a plan view of the device, and FIG. 1B is a cross-sectional view. 1 (a) and 1 (b), reference numeral 1 denotes an insulating substrate, 2 and 3 denote a pair of device electrodes for applying a voltage to the device, 4 denotes a conductive thin film, and 5 denotes an electron emitting portion. In the drawing, L represents the electrode interval between the device electrodes 2 and 3, and W represents the width of the electronic electrode.

A method for fabricating the electron-emitting device of this embodiment will be described with reference to FIG. Using a blue board as the insulating substrate 1,
This was sufficiently washed with an organic solvent and pure water and dried with hot air at 200 ° C. Element electrodes 2 and 3 were formed on the substrate by offset printing (see FIG. 2A).

In this example, a Pt resinate paste composed of an organic metal was used as the ink. The ink on the quartz substrate is formed as a Pt element electrode by drying at about 70 ° C. and baking at about 580 ° C. The thickness of the Pt electrode after firing was as thin as about 100 nm. The dimension between the device electrodes on which the electron-emitting materials are arranged was set to 30 μm.

Next, a BJ type ink jet apparatus (C
anion BJ-10V), 70% by weight of water
A solution in which palladium monoethanolamine (hereinafter abbreviated as PAME) was adjusted to 1 wt% in a solution containing 30 wt% of PA + ethylene glycol + PVA was placed on the device electrode treated as described above (FIG. 2 (b)). See)) dried. This was heated to 300 ° C. to form a fine particle film composed of PdO fine particles, which was used as a conductive thin film 4 (FIG. 2C).
reference).

The average particle size of the fine particle film was 9 nm. The thickness of the conductive thin film 4 was 10 nm, and the sheet resistance was 5 × 10 ⁴ Ω / □. Next, the device electrodes 2,
A voltage was applied between the electrodes 3 and the conductive thin film 4 was subjected to an energizing process (forming process) to form an electron-emitting portion 5 (see FIG. 2D).

FIG. 3 shows a voltage waveform of the forming process. In FIG. 3, T1 and T2 are the pulse width and pulse interval of the voltage waveform. In this embodiment, T1 is 1 ms, and T2 is 1
0 ms, the peak value of the triangular wave (peak voltage at the time of forming) is 4 V, and the forming process is about 1.3 × 10
^This was performed for 60 seconds under a pressure atmosphere of ^-4 Pa.

Next, a display panel of an image forming apparatus as shown in FIG. 12 was prepared using the electron-emitting device thus prepared. FIG. 13 is a sectional view (A-
A 'part of the section). FIG. 12 is basically the same as FIG. 7 except that a spacer 89 is provided. That is, the substrate 81 on which the conductive thin film is formed by the above-described method is replaced with the rear plate 9 made of blue glass.
1, a face plate 96 made of soda lime glass (formed by forming a fluorescent film 94 and a metal back 95 on the inner surface of a glass substrate 93) is placed 5 mm above the substrate 81. A spacer 89 having a thickness of 300 μm was assembled by polishing a soda lime glass and placing the spacer 89 therebetween.

Next, the face plate 96, the support frame 9
2. Apply the frit glass paste prepared according to the above specifications to the joint of the rear plate 91,
After drying for 0 minutes to volatilize the solvent, baking was performed at 410 ° C. for 10 minutes or more to seal. FIG. 20 shows a process flow chart at this time.

The resulting frit glass fired body 8
The bonding strength of 0 is sufficient, and the electron-emitting devices around the frit glass (around the support frame and the spacer) do not undergo deterioration such as reduction or aggregation, and show no change in resistance and have good electron emission characteristics. showed that. In addition, the image forming apparatus exhibited bright and favorable display with little variation in luminance.

Example 2 In Example 2, the same frit glass powder as in Example 1 was used. In this example, AEROSI manufactured by Nippon Aerosil Co., Ltd. was used as a thickener.
LCIT84 (a 5: 1 mixture of SiO ₂ and Al ₂ O ₃ , suitable for thickening water and other polar systems) mixed with 5 wt% of water and dispersed is used to mix frit glass powder. Into a frit glass paste. The dispersion of AEROSILCOK84 was 1 part by weight with respect to 5 parts by weight of the frit glass powder at this time. The viscosity at this time is about 17000 mP
as. Figure 18 shows AEROSILCOK84 in water
And a thickening effect of 200.

Using this frit paste, Example 1
An electron-emitting device was prepared in the same manner as in Example 1, and a display panel of the image forming apparatus was formed in the same manner as in Example 1. FIG. 20 shows a process flow chart at this time. The fixing strength of the fired frit glass body obtained as a result was sufficient as in Example 1, and no deterioration of the electron-emitting device in the periphery of the frit glass was observed, indicating good electron emission characteristics.

Comparative Example The same frit glass powder as in Example 1 was used, and a frit glass paste was prepared by mixing an acrylic resin binder as a thickener with 10 wt% dissolved in terpineol. The mixing ratio at this time was 5 parts by weight of the frit glass powder and 1 part by weight of the binder solution. At this time, the viscosity was about 20,000 mPa.

Using this frit paste, Example 1
An electron-emitting device was prepared in the same manner as in Example 1, and a display panel of the image forming apparatus was formed in the same manner as in Example 1. At this time, in order to decompose the binder, between the drying and baking of the solvent, 3
It was necessary to add a calcination step at 80 ° C. for several minutes. FIG. 20 shows a process flow chart at this time.

Further, a large amount of gas was generated due to the combustion decomposition of the binder during the preliminary firing. In particular, the reducing gas such as hydrogen or carbon monoxide in the contact with the electron-emitting device around the frit glass causes deterioration such as reduction and aggregation, and the resistance value was increased. . As a result, forming failure occurred, and good electron emission characteristics could not be obtained. Further, in the image forming apparatus, a decrease in brightness and a variation occurred near the spacer and the support frame.

[0127]

As described above, according to the present invention, by using silica fine particles instead of an organic binder as a thickening agent for a frit glass mixture, the frit glass mixture can be used as in the case of using an organic binder during frit firing. Generation of reducing gas due to combustion decomposition can be avoided.

As a result, the conductive fine particles in the vicinity of the frit agent are not deteriorated such as reduction or agglomeration.
Therefore, a forming failure can be avoided. Furthermore, even when a large number of electron-emitting devices are formed over a large area, uniform electron-emitting characteristics can be obtained, and a favorable display device and an excellent image forming apparatus can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic plan view and a cross-sectional view illustrating a configuration of a surface conduction electron-emitting device to which the present invention can be applied.

FIG. 2 is a process explanatory view showing an example of a method for manufacturing a surface conduction electron-emitting device to which the present invention can be applied.

FIG. 3 is a graph showing an example of a voltage waveform in an energization forming process that can be employed in manufacturing a surface conduction electron-emitting device to which the present invention can be applied.

FIG. 4 is a schematic view illustrating an example of a vacuum processing apparatus having a measurement evaluation function.

FIG. 5 is a graph showing an example of the relationship between the emission current Ie, the device current If, and the device voltage Vf for a surface conduction electron-emitting device to which the present invention can be applied.

FIG. 6 is a schematic diagram showing an example of an electron source arranged in a simple matrix to which the present invention can be applied.

FIG. 7 is a partially cutaway perspective view showing an example of a display panel of an image forming apparatus having a simple matrix arrangement to which the present invention can be applied.

FIG. 8 is a schematic view illustrating an example of a fluorescent film.

FIG. 9 is a block diagram illustrating an example of a drive circuit for performing display on an image forming apparatus according to an NTSC television signal.

FIG. 10 is a schematic view showing an example of an electron source having a ladder arrangement to which the present invention can be applied.

FIG. 11 is a partially cutaway perspective view showing an example of an image forming apparatus display panel having a ladder arrangement to which the present invention can be applied.

FIG. 12 is a partially cutaway perspective view showing a configuration of an image forming apparatus to which the method of the present invention is applied.

FIG. 13 is a schematic sectional view showing a part of the image forming apparatus (FIG. 12) to which the method of the present invention is applied.

FIG. 14 is a schematic view showing an example of a Hartwell surface conduction electron-emitting device.

FIG. 15 is an explanatory diagram showing an interaction between AEROSIL particles in a liquid.

FIG. 16 is a graph showing the thickening effect of various liquids of AEROSIL 200 (manufactured by Nippon Aerosil Co., Ltd.).

FIG. 17 is a graph (electron micrograph) showing the particle size distribution of AEROSIL 200 (manufactured by Nippon Aerosil Co., Ltd.) and a graph showing a particle size distribution curve of primary particles of various AEROSILs.

FIG. 18. AEROSIL200 and AEROSILCOK8 in water
4 is a graph showing the thickening effect of No. 4.

FIG. 19 is an exploded perspective view showing an outline of a conventional image forming display device with spacers, and a longitudinal sectional view thereof.

FIG. 20 is a process flow chart showing steps of an example and a comparative example.

FIG. 21 is an explanatory process diagram showing a conventional method for manufacturing an image forming apparatus using a surface conduction electron-emitting device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Substrate 2, 3 Device electrode 4 Conductive thin film 5 Electron emission part 60 Ammeter for measuring device current If flowing through conductive thin film 4 between device electrodes 2 and 3 61 Apply device voltage Vf to an electron emission device Power supply 62 for measuring the emission current Ie flowing between the electron emission section 5 and the anode electrode 64 63 high voltage power supply for applying a voltage to the anode electrode 64 64 emission current emitted from the electron emission section of the element Ie
Anode electrode 65 for capturing air 65 Vacuum device 66 Exhaust pump 80 Frit glass 81 Electron source substrate 82 X-directional wiring 83 Y-directional wiring 84 Surface conduction electron-emitting device 85 Connection 89 Spacer 91 Rear plate 92 Support frame 93 Glass substrate 94 Fluorescence Film 95 metal back 96 face plate 97 high voltage terminal 98 envelope 101 black conductive material 102 phosphor 111 display panel 112 scanning circuit 113 control circuit 114 shift register 115 line memory 116 synchronous signal separation circuit 117 modulation signal generator 120 electron source substrate 121 Electron-emitting device 122 Dx1 to Dx10 (common wiring for wiring the electron-emitting device) 130 Grid electrode 131 Hole for passing electrons 132 Dox1, Dox2,... 133 connected to the grid electrode 130 G1, G2,
... External container terminal composed of Gn Vx, Va DC voltage source

Claims (10)

[Claims] In a manufacturing method of assembling an image forming apparatus having an electron-emitting device via a glass frit, a glass frit agent comprises glass frit as a main component, inorganic fine particles as a thickener, a solvent or water. A method for manufacturing an image forming apparatus, comprising: 2. The method according to claim 1, wherein the inorganic fine particles are mainly composed of silica fine particles obtained by a gas phase reaction. 3. The particle size of the silica fine particles is 1 to 1
The method for manufacturing an image forming apparatus according to claim 1, wherein the thickness is in a range of 00 nm. 4. The method for manufacturing an image forming apparatus according to claim 1, wherein the content of the silica fine particles is in a range of 1 to 50 wt% based on a solvent or water. 5. The electron-emitting device according to claim 1, wherein the electron-emitting device is a surface-conduction electron-emitting device having an electron-emitting portion formed of a conductive thin film between opposing electrodes.
The method for manufacturing an image forming apparatus according to any one of the above. 6. The method according to claim 1, wherein the conductive thin film is made of fine particles. 7. The method for manufacturing an image forming apparatus according to claim 1, wherein said conductive thin film is made of Pd or PdO. 8. An electron-emitting device obtained by the manufacturing method according to claim 1. 9. An image display device comprising the electron-emitting device according to claim 8. 10. An image forming apparatus comprising the image display device according to claim 9.