JP2000082384A - Electron emitting device, electron source, image forming apparatus, and method of manufacturing electron emitting device - Google Patents

Abstract

(57) [Problem] To provide an electron-emitting device having a high electric heat resistance temperature. SOLUTION: In a surface conduction electron-emitting device in which a pair of device electrodes and a conductive thin film having an electron-emitting portion between the device electrodes are formed on a substrate, the conductive thin film is made of a platinum group element, At least on the surface in contact with the conductive thin film has a subbing film containing SiO ₂ as a main component and containing bismuth oxide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface conduction electron-emitting device, an electron source using the electron-emitting device, and an image forming apparatus using the electron source.

[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 “FE type”), a metal / insulating layer / metal type (hereinafter, referred to as “MIM type”), a surface conduction type electron emitting device, and the like. An example of the FE type is WPDyke & W.
W. Dolan, “Field Emission”, Advance in Electoron Ph
ysics, 8, 89 (1956), or CASpindt, “Physical
Properties of Thin-Film Field Emission Cathodes wi
th Molybdenium cones ”, J. Apply.Phys., 47, 5248 (1976)
And the like are known. CAMead, “Operation of Tunnel-Emission Device” is an example of the MIN type.
s ”, J. Apply. Phys., 32, 646 (1961) and the like. Examples of surface conduction electron-emitting devices include MIElinson, Recio Eng. ElectronPhys., 10, 1290 ( 19
65). The surface conduction electron-emitting device utilizes the phenomenon that electron emission occurs when a current flows in a small-area thin film formed on a substrate in parallel with the film surface. Examples of the surface conduction electron-emitting device include a device using an SnO ₂ thin film by Elinson et al. And a device using an Au thin film [G. Dittmer: “Thin Solid Film”.
s ”, 9,317 (1972)], using an In ₂ O ₃ / SnO ₂ thin film [M. Hartwell and CGFonstad:“ IEEE Trans.ED Con
f. ”519 (1975)], based on carbon thin film [Hisashi Araki et al .:
Vacuum, Vol. 26, No. 1, p. 22 (1983)] and the like.

A typical example of these surface conduction electron-emitting devices is M. FIG. 16 schematically shows an element configuration of the Hartwell. In FIG. 1, reference numeral 1 denotes a substrate. Reference numeral 4 denotes a conductive thin film, which is formed of a metal oxide thin film or the like formed by sputtering in an H-shaped pattern, and the electron emitting portion 5 is formed by an energization process called energization forming described later. still,
In the figure, the element electrode interval L is 0.5 to 1 mm, and W is 0.
It is set to 1 mm. Conventionally, in these surface conduction electron-emitting devices, the electron-emitting portion 5 is generally formed by applying an energization process called energization forming to the conductive thin film 4 before emitting electrons. That is, the 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, and electrically. This is to form the electron-emitting portion 5 in a high-resistance state. 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.

[0004]

SUMMARY OF THE INVENTION The present applicant has disclosed, for example, Japanese Patent Application Laid-Open No. 7-235255,
It has been reported that it is preferable to form a conductive thin film including an electron-emitting portion using an appropriate material different from the device electrode. As a material of the conductive thin film, a platinum group metal such as Pd or an oxide thereof is preferably used. However, under a specific atmosphere containing a gas that promotes aggregation of the conductive thin film, such as hydrogen gas, the electric heat resistant temperature is 40 ° C.
In some cases, the temperature was 0 ° C. or lower, which was a constraint on the manufacturing process. Note that, in this specification, the “electrically heat-resistant temperature” refers to a temperature at which the aggregation of the conductive thin film progresses and conduction cannot be achieved.

An object of the present invention is to provide an electron-emitting device having a high electric heat resistance temperature.

[0006]

Means for Solving the Problems The present invention has been made by intensive studies in order to solve the above-mentioned problems, and has the following configuration. That is, the surface conduction electron-emitting device of the present invention is a surface conduction electron-emitting device in which a pair of device electrodes and a conductive thin film having an electron-emitting portion are formed between the device electrodes. The thin film is made of a platinum group element, and at least a surface of the substrate in contact with the conductive thin film contains SiO ₂ as a main component, and
An electron-emitting device comprising a subbing film containing bismuth oxide particles.

Further, the conductive thin film is made of a platinum group element -P
d, Pt, and Ru are preferred, and Pd is particularly preferred.

The platinum group compound is not particularly limited as long as it is a complex or a salt which can be fired, but an amine complex which is stable in an aqueous solution is preferred.

The undercoating film has a SiO ₂ film as a main component, and among the bismuth oxide particles contained therein, the bismuth oxide particles present on the surface in contact with the conductive thin film are formed of the entire metal contained in the conductive thin film. Is preferably 1 to 10 mol% when the value is 100 mol%.

Further, the present invention includes an electron source and an image forming apparatus.

An electron source according to the present invention is an electron source that emits electrons in response to an input signal. The electron source includes a plurality of the above-described electron-emitting devices arranged on a substrate. It is characterized in that it has a plurality of rows of electron-emitting devices connected to the wiring and further has modulation means. More preferably, a plurality of electron-emitting devices in which a pair of device electrodes of the electron-emitting device are connected to m X-direction wires and n Y-direction wires that are electrically insulated from each other on the base are arranged. It is characterized by having done.

The image forming apparatus of the present invention forms an image based on an input signal, and is characterized by comprising at least an image forming member and the above-mentioned electron source.

[Operation] By providing the subbing film 6 containing the bismuth oxide particles 7 between the conductive fine particle film 4 and the substrate 1 of the electron-emitting device of the present invention, the electric heat resistance temperature is increased. This is presumed that Bi functions as a buffer layer between the conductive fine particle film and the substrate and stabilizes the shape of the fine particle film. It is presumed that this action is due to the low temperature (271.3 ° C.) of the melting point of Bi or the electron configuration (the deepest term ⁴ S _3/2 ).

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

The basic structure of the surface conduction electron-emitting device according to the present embodiment is roughly classified into two types: a plane type and a vertical type. First, the flat surface conduction electron-emitting device will be described.

FIG. 1 is a schematic view showing an example of a surface conduction electron-emitting device according to the present invention (a diagram showing the features of the present invention best). In FIG. 1, 1 is a substrate, 2 and 3 are device electrodes, 4 is an electron-emitting portion forming material (fine particle film), 5 is an electron-emitting portion, 6 is a subbing film, and 7 is B deposited in the subbing film.
iO particles.

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 a Si substrate. Can be used.

Materials for the opposing element electrodes 2 and 3 include:
General conductor materials can be used. This is, for example, Ni, Cr, Au, Mo, W, Pt, Ti, Al, C
metals or alloys such as u, Pd and Pd, Ag, Au, Ru
Appropriately selected from a printed conductor composed of a metal or metal oxide such as O ₂ or Pd-Ag and glass, a transparent conductor such as In ₂ O ₃ —SnO ₂ and a semiconductor conductor material such as polysilicon. Can be.

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 is preferably in the range of several hundred nm to several hundred μm, more preferably several μm.
m to several tens of μm. The length W of the device electrode is several μm in consideration of the resistance value of the electrode and the electron emission characteristics.
m to several hundred μm. The film thickness d of the device electrodes 2 and 3 can be in the range of several tens nm to several μm.

In addition to the structure shown in FIG.
A configuration in which the conductive thin film 4 and the opposing device electrodes 2 and 3 are stacked in this order may be adopted.

As the conductive thin film 4, it is preferable to use a fine particle film composed of fine particles in order to obtain good electron emission characteristics. The film thickness is appropriately set in consideration of the step coverage for the device electrodes 2 and 3, the resistance value between the device electrodes 2 and 3, a forming condition described later, and the like.
It is preferably in the range of several times 0.1 nm to several hundred nm, more preferably in the range of 1 nm to 50 nm. The resistance value of Rs is 102 to 107Ω / □.
Is the value of In the specification of the present application, 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 a film to form a high resistance state. It is.

In the present invention, the material constituting the conductive thin film 4 is preferably a platinum group element -Pd, Pt, Ru.
Particularly, Pd is preferable.

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 overlapped (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 to several hundred nm of 0.1 nm, preferably in the range of 1 nm to 20 nm.
In this specification, the term “fine particles” is frequently used, and the 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. Further, “fine particles” and “ultrafine particles” may be collectively referred to as “fine particles”, and the description in this specification is in line with this. "Experimental Physics Course 14: Surfaces and Particles" (edited by Kinoshita Yoshio, published by Kyoritsu Shuppan, September 1, 1986) states as follows. "When we say fine particles in this paper, the diameter is about 2-3 μm to 1
It is assumed to be up to about 0 nm, and particularly when it is referred to as ultrafine particles, it means that the particle size is from about 10 nm to about 2 to 3 nm. It is not exactly strict because both are collectively written as fine particles, but it is a rough guide. When the number of atoms constituting a particle is two to several tens to several hundreds, it is called a cluster. (P. 195, lines 22-26) In addition, the definition of "ultrafine particles" in the Hayashi / Ultrafine Particle Project of the New Technology Development Corporation is that the lower limit of particle size is even smaller, as follows: there were. "Creative Science and Technology Promotion System" Ultra Fine Particle Project "(1981-1
986), the size (diameter) of the particles is approximately 1 to 100
In the range of nm, “ultrafine particles” (ultrafine)
participant). Then one of the ultra-fine particles is made to the fact that the aggregate of approximately 10 ⁰ to 10 ⁸ or much of the atom. Ultrafine particles are large on an atomic scale.
Giant particles. ("Ultrafine Particles-Creative Science and Technology-" Shareholder Tax, Ryoji Ueda and Akira Tazaki; Mita Publishing 1988 2
Lines 1 to 4) "Things smaller than ultrafine particles,
In other words, a single particle composed of several to several hundred atoms is usually called a cluster. "
-13th line) Based on the above general term,
In the present specification, the term “fine particles” refers to an aggregate of a large number of atoms and molecules, and the lower limit of the particle size is from several times 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 the method of energization forming and the like to be described later. It will be. Inside the electron emission unit 5,
In some cases, conductive fine particles having a particle size ranging from several times 0.1 nm to several tens nm are present. 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.

Next, a vertical surface conduction electron-emitting device will be described. FIG. 2 is a schematic diagram showing an example of a vertical surface conduction electron-emitting device to which the surface conduction electron-emitting device of the present invention can be applied.

In FIG. 2, the same parts as those shown in FIG. 1 are denoted by the same reference numerals as those shown in FIG.
21 is a step forming part. The substrate 1, the device electrodes 2 and 3, the conductive thin film 4, and the electron-emitting portion 5 can be made of the same material as in the case of the above-described flat surface conduction electron-emitting device. The step forming part 21 is formed by a vacuum deposition method, a printing method,
It can be made of an insulating material such as SiO ₂ formed by a sputtering method or the like. The film thickness of the step forming portion 21 corresponds to the device electrode interval L of the flat surface conduction electron-emitting device described above, and can be in the range of several hundred nm to several tens μm. This film thickness is set in consideration of the manufacturing method of the step forming portion and the voltage applied between the device electrodes, but is preferably in the range of several tens nm to several μm. The conductive thin film 4 includes the element electrode 2
After the steps 21 and 22 and the step forming portion 21 are formed, they are laminated on the device electrodes 2 and 3. Although the electron emitting portion 5 is formed in the step forming portion 21 in FIG. 2, the shape and the position are not limited to this depending on the forming conditions, forming conditions and the like. The undercoat film 6 is provided on the surface of the step forming portion 21.
Are formed. In the figure, the undercoat film 6 is formed on the entire step forming portion 21, but may be provided at a portion where the electron emitting portion 5 is formed.

There are various methods for manufacturing the above-mentioned surface conduction electron-emitting device. One example is schematically shown in FIG. Hereinafter, an example of the manufacturing method will be described with reference to FIGS. 1 and 3 (in FIG. 3, the same portions as those shown in FIG. 1 are denoted by the same reference numerals as those in FIG. 1). .).

The substrate 1 is sufficiently washed with a detergent, pure water, an organic solvent or the like, and a subbing film 6 is formed on at least the surface of the substrate in contact with the conductive thin film 4. The SiO ₂ film which is a main component of the undercoat film 6 is formed by using a liquid coating agent.
It is convenient to form it by a coating / dipping method or by applying a droplet of a solution. An aqueous solution containing a Bi compound or a mixture of BiO is applied to the substrate 1 or immersed in the liquid coating agent or formed by applying a droplet of the solution (FIG. 3).
(A)).

Thereafter, after the device electrode material is deposited by a vacuum deposition method, a sputtering method or the like, the device electrodes 2 and 3 are formed on the substrate 1 by using, for example, a photolithography technique (FIG. 3).
(B)). The undercoat film may or may not be provided under the device electrode. If not, the undercoat film may be formed after the device electrode is formed.

An organic metal solution is applied to the substrate 1 provided with the device electrodes 2 and 3 to form an organic metal 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. The organic metal thin film is heated and baked, and patterned by lift-off, etching, or the like to form a conductive thin film 4 (FIG. 3).
(C)). Here, the method of applying the organometallic solution has been described, but the method of forming the conductive thin film 4 is not limited to this, and a vacuum evaporation method, a sputtering method, a chemical vapor deposition method,
A dispersion coating method, a dipping method, a spinner method, or the like can also be used.

Subsequently, a forming step is performed. As an example of a method of the forming step, a method by an energization process will be described. When an electric current 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 the portion of the conductive thin film 4 (FIG. 3D). 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.
This portion constitutes the electron emission section 5. FIG. 4 shows an example of the voltage waveform of the energization forming.

The voltage waveform is preferably a pulse waveform. The method shown in FIG. 4A in which a pulse having a pulse peak value of a constant voltage is continuously applied and the method shown in FIG. 4B in which a voltage pulse is applied while increasing the pulse peak value are used. There is. T ₁ and T ₂ in FIG. 4 (a) is a pulse width and the pulse interval of the voltage waveform. Normally T ₁ is ₁ μsec
〜１０10 msec, T ₂ is 10 μsec〜１０10 msec
Is set in the range. The peak value of the triangular wave (peak voltage at the time of energization forming) is appropriately selected according to the form of 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. T ₁ and T ₂ in FIG. 4B can be the same as those shown in FIG. 4A. The peak value of the triangular wave (peak voltage during energization forming) can be increased by, for example, about 0.1 V / step. The end of the energization forming process can be detected by applying a voltage that does not locally destroy or deform the conductive thin film ₂ during the pulse interval T2, and measuring the current. For example, an element current flowing by applying a voltage of about 0.1 V is measured, and a resistance value is obtained. When the resistance value indicates 1 MΩ or more, the energization forming is terminated.

It is preferable to perform a process called an activation step on the element after the forming. The activation step
In this step, the element current If and the emission current Ie change significantly. The activation step can be performed, for example, by repeatedly applying a pulse in an atmosphere containing a gas of an organic substance, similarly to the energization forming. This atmosphere can be formed by 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, or is sufficiently evacuated once by an ion pump or the like. It can also be obtained by introducing a gas of an appropriate organic substance into a vacuum. 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. Suitable organic substances include alkanes, alkenes, aliphatic hydrocarbons of alkynes, aromatic hydrocarbons, alcohols, aldehydes, kents, amines, phenols, carvone,
Examples thereof include organic acids such as sulfonic acid. Specific examples thereof include saturated hydrocarbons represented by CnH _{2n + 2} such as mentha, ethane, and propane, ethylene, propylene, and the like.
Unsaturated hydrocarbon represented by a composition formula such as _2n , benzene, toluene, methanol, ethanol, formaldehyde,
Acetaldehyde, acetone, methyl ethyl ketone, methylamine, ethylamine, phenol, formic acid, acetic acid,
Propionic acid or the like or a mixture thereof can be used.
By this treatment, carbon or a carbon compound is deposited on the device from organic substances existing in the atmosphere, and the device current I
f, the emission current Ie changes 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 (so-called HOPG ', PG (, GC); HOPG has a substantially complete graphite crystal structure;
G indicates that the crystal grain is about 200 ° and the crystal structure is slightly disordered, and GC indicates that the crystal grain is about 20 ° and the disorder of the crystal structure is further increased. ) And amorphous carbon (refer to amorphous carbon and a mixture of amorphous carbon and the microcrystals of graphite), and the thickness thereof is preferably in the range of 50 nm or less.
It is more preferable to set the range to 0 nm or less.

It is preferable that the electron-emitting device obtained through such a step be subjected to a stabilizing step. This step is
This is a step of exhausting the organic substance in 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. Specifically, a vacuum exhaust device such as a sorption pump or 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 suppressed as low as possible. The partial pressure of the organic component in the vacuum container is preferably 1.3 × 10 ⁻⁶ Pa or less as a partial pressure at which the carbon and the carbon compound hardly newly deposit.
Further, the pressure is particularly preferably 1.3 × 10 ⁻⁸ Pa or less. 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 80 to 250 ° C, preferably 150 ° C or more,
It is desirable to perform the treatment as long as possible, but the treatment is not particularly limited to this condition, and the treatment is performed under conditions appropriately selected according to various conditions such as the size and shape of the vacuum vessel and the configuration of the electron-emitting device. The pressure in the vacuum vessel needs to be as low as possible, preferably 1 × 10 ⁻⁵ Pa or less, and more preferably 1.3 × 1 ⁻⁵ Pa.
0 ^-6 Pa or less is particularly preferred.

It is preferable that the atmosphere at the time of driving after the stabilization process is performed is the same as that at the end of the stabilization treatment. However, the present invention is not limited to this, as long as the organic substances are sufficiently removed. Even if the degree of vacuum itself is slightly reduced, sufficiently stable characteristics can be maintained. By adopting such a vacuum atmosphere, the deposition of new carbon or a carbon compound can be suppressed, and H
Such as ₂ 0,0 ₂ also be removed, resulting in the device current If, the emission current Ie are stabilized.

The basic characteristics of the electron-emitting device to which the present invention can be applied obtained through the above steps will be described with reference to FIGS.

FIG. 5 is a schematic diagram showing an example of a vacuum processing apparatus. This vacuum processing apparatus also has a function as a measurement and evaluation apparatus. Also in FIG. 5, the same parts as those shown in FIG. 1 are denoted by the same reference numerals as those shown in FIG. In FIG. 5, 55 is a vacuum vessel, and 56 is an exhaust pump. An electron-emitting device is provided in the vacuum vessel 55. That is, 1 is a substrate constituting an electron-emitting device, 2 and 3 are device electrodes, 4 is a conductive thin film, and 5 is an electron-emitting portion. 51 is a device voltage Vf applied to the electron-emitting device.
, A current meter 50 for measuring a device current If flowing through the conductive thin film 4 between the device electrodes 2 and 3, and an emission current I 54 emitted from an electron emission portion of the device.
This is an anode electrode for capturing e. Reference numeral 53 denotes a high-voltage power supply for applying a voltage to the anode electrode 54, and reference numeral 52 denotes an ammeter for measuring an 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 kV to 10 kV and the distance H between the anode electrode and the electron-emitting device in the range of 2 mm to 8 mm.

In the vacuum vessel 55, equipment necessary for measurement in a vacuum atmosphere such as a vacuum gauge (not shown) is provided.
The measurement and evaluation can be performed in a desired vacuum atmosphere. The exhaust pump 56 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 equipped with the electron source substrate shown here is
It can be heated by a heater (not shown). Therefore, by using this vacuum processing apparatus, the steps after the energization forming described above can also be performed.

FIG. 6 shows emission current Ie, device current If, and 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 is apparent from FIG. 6, 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. 7) or more is applied to the element, the emission current I suddenly increases.
e increases, while the emission current Ie is hardly detected below the threshold voltage Vth. That is, it is a nonlinear element having a clear threshold voltage Vth with respect to the emission current Ie.

(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 54 depends on the time during which the device voltage Vf is applied. That is, the amount of charge captured by the anode electrode 54 can be controlled by the time during which the device voltage Vf is applied. As understood from the above description, the surface conduction electron-emitting device to which the present invention can be applied can easily control the electron emission characteristics in accordance with the input signal. Utilizing this property, an electron source constituted by arranging a plurality of electron-emitting devices, an image forming apparatus, etc.
Application to various fields becomes possible.

In FIG. 6, an example in which the element current If monotonically increases with respect to the element voltage Vf (hereinafter, referred to as "MI characteristic") is shown by a solid line. The element current If is equal to the element voltage Vf.
May exhibit a voltage control type negative resistance characteristic (hereinafter, referred to as “VCNR characteristic”) in some cases (not shown). These characteristics can be controlled by controlling the aforementioned steps. An application example of an 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 a matrix 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. The other of the electrodes of the plurality of electron-emitting devices arranged in the same row is
One that is commonly connected to the wirings in the directions is given. 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 characteristics (i) to (iii) as described above. That is, when the electrons emitted from the surface conduction electron-emitting device are equal to or higher than the threshold voltage, they 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, it is hardly 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, based on this principle, an electron source substrate obtained by disposing a plurality of electron-emitting devices to which the present invention can be applied will be described with reference to FIG. In FIG. 7, reference numeral 71 denotes an electron source substrate, 72 denotes an X-direction wiring, and 73 denotes a Y-direction wiring.
74 is a surface conduction electron-emitting device, and 75 is a connection.
Incidentally, the surface conduction electron-emitting device 74 may be either the above-mentioned flat type or vertical type.

The m X-directional wirings 72 include 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 73 includes n wirings 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 the m X-directional wirings 72 and the n Y-directional wirings 73 to electrically separate them (m and n are both Positive integer).

The interlayer insulating layer (not shown) is made of SiO ₂ or the like formed by a vacuum deposition method, a printing method, a sputtering method, or the like. For example, it is formed in a desired shape on the entire surface or a part of the substrate 71 on which the X-directional wiring 72 is formed. The material and manufacturing method are appropriately set. The X-direction wiring 72 and the Y-direction wiring 73 are respectively drawn out as external terminals.

A pair of electrodes (not shown) constituting the surface conduction electron-emitting device 74 are electrically connected to the m X-directional wires 72 and the n Y-directional wires 73 by a connection 75 made of a conductive metal or the like. Have been.

The material forming the wiring 72 and the wiring 73, the material forming the connection 75, and the material forming the pair of element electrodes may be partially or entirely the same or different from each other. Good. 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.

A scanning signal applying means (not shown) for applying a scanning signal for selecting a row of the surface conduction electron-emitting devices 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 column of the surface conduction electron-emitting devices 74 arranged in the Y direction according to an input signal is connected to the Y-direction wiring 73. 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. 8, 9 and 10. FIG. FIG. 8 is a schematic view showing an example of a display panel of the image forming apparatus, and FIG. 9 is a schematic view of a fluorescent film used in the image forming apparatus of FIG. FIG.
FIG. 2 is a block diagram showing an example of a drive circuit for performing display according to an NTSC television signal.

In FIG. 8, reference numeral 71 denotes an electron source substrate on which a plurality of electron-emitting devices are arranged; 81, a rear plate on which the electron source substrate 71 is fixed; 86, a fluorescent film 84 on the inner surface of a glass substrate 83;
And a face plate on which a metal back 85 and the like are formed. Reference numeral 82 denotes a support frame to which a rear plate 81 and a face plate 86 are joined by using low melting point frit glass or the like. Reference numeral 74 denotes a surface conduction electron-emitting device. Numerals 72 and 73 denote X-directional wiring and Y connected to a pair of device electrodes of the surface conduction electron-emitting device.
Directional wiring. The envelope 88 includes the face plate 86, the support frame 82, and the rear plate 81 as described above. 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 unnecessary. That is, the support frame 82 may be directly sealed to the substrate 71, and the envelope 88 may be configured by the face plate 86, the support frame 82, and the substrate 71. On the other hand, the face plate 86,
By providing a support (not shown) called a spacer between the rear plates 81, an envelope 88 having sufficient strength against atmospheric pressure can be formed.

FIG. 9 is a schematic diagram showing a fluorescent film. The fluorescent film 84 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 91 called a black stripe or a black matrix and a fluorescent material 92 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 92 of the necessary three primary color phosphors black in the case of color display, An object of the present invention is to suppress a decrease in contrast due to light reflection. As a material for the black stripe, a material which is conductive and has little light transmission and reflection can be used in addition to a commonly used material mainly containing graphite. As a method of applying the phosphor on the glass substrate 93, a precipitation method, a printing method, or the like can be adopted regardless of monochrome or color. Usually, a metal back 85 is provided on the inner surface side of the fluorescent film 84. The purpose of providing the metal back is to improve the brightness by mirror-reflecting light toward the inner surface side of the phosphor emission toward the face plate 86 side, to act as an electrode for applying an electron beam acceleration voltage, The purpose is to protect the phosphor from damage due to collision of negative ions generated in the envelope. The metal back is
After the formation of the fluorescent film, a smoothing treatment (usually called “filming”) of the inner surface of the fluorescent film is performed, and then A
1 can be produced by depositing using vacuum evaporation or the like.
In order to further increase the conductivity of the fluorescent film 84, a transparent electrode (not shown) is provided on the face plate 86 on the outer surface side of the fluorescent film 84.
May be provided.

When performing the above-mentioned sealing, in the case of color, it is necessary to make each color phosphor correspond to an electron-emitting device.
Sufficient alignment is essential.

An example of a method for manufacturing the image forming apparatus shown in FIG. 8 will be described below. FIG. 11 is a schematic diagram showing an outline of an apparatus used in this step. The image forming apparatus 131 is connected to a vacuum chamber 133 via an exhaust pipe 132, and further connected to an exhaust apparatus 135 via a gate valve. The vacuum chamber 133 has a pressure gauge 1 for measuring the internal pressure and the partial pressure of each component in the atmosphere.
36, a quadrupole mass spectrometer (Q-mass) 137 and the like are attached. Since it is difficult to directly measure the pressure inside the envelope 88 of the image display device 131, the processing conditions are controlled by measuring the pressure inside the vacuum chamber 133 and the like. A gas introduction line 138 is connected to the vacuum chamber 133 in order to introduce necessary gas into the vacuum chamber and control the atmosphere. An introduction substance source 140 is connected to the other end of the gas introduction line 138, and the introduction substance is stored in an ampoule or a cylinder. In the middle of the gas introduction line, there is provided a gas introduction control device (introduction control means) 139 for controlling the rate at which the introduced substance is introduced. Specifically, as the gas introduction control device 139, a valve such as a slow leak valve that can control the flow rate to be released, a mass flow controller, or the like can be used according to the type of the substance to be introduced. The inside of the envelope 88 is evacuated by the apparatus shown in FIG. 11 to perform forming. At this time, for example, as shown in FIG.
A power supply 142 is applied to an element connected to one of the
Accordingly, forming can be performed by applying a voltage pulse at the same time. Conditions such as the shape of the pulse and the determination of the end of the processing may be selected according to the above-described method for forming the individual elements. In addition, by sequentially applying (scrolling) a pulse with a phase shifted to a plurality of X-direction wirings, it is possible to form elements connected to the plurality of X-direction wirings collectively. In the figure, reference numeral 143 denotes a current measuring resistor, and 144 denotes a current measuring oscilloscope. After the forming is completed, an activation step is performed. After sufficiently exhausting the inside of the envelope 88, the organic substance is introduced from the gas introduction line 138. Alternatively, as described in the method of activating the individual elements, first, an exhaust may be performed by an oil diffusion pump or a rotor pump, and thereby, an organic substance remaining in a vacuum atmosphere may be used. In addition, substances other than organic substances may be introduced as necessary. By applying a voltage to each electron-emitting device in an atmosphere containing an organic substance formed in this manner, carbon or a carbon compound, or a mixture of both, is deposited on the electron-emitting portion, and the amount of emitted electrons is drastic. Is similar to the case of the individual element. At this time, the voltage may be applied by applying the same voltage pulse to the elements connected to one direction wiring by the same connection as in the above-described forming. After completion of the activation step, it is preferable to perform a stabilization step as in the case of the individual element. Envelope 88
Is heated and maintained at 80 to 250 ° C., and is exhausted through an exhaust pipe 132 by an exhaust device 135 that does not use oil, such as an ion pump and a sorption pump. Heat with a burner to dissolve and seal. In order to maintain the pressure after the envelope 88 is sealed, a getter process may be performed. This is because the getter disposed at a predetermined position (not shown) in the envelope 88 is heated by heating using resistance heating, high-frequency heating, or the like immediately before or after the envelope 88 is sealed. This is a process for forming a deposited film. The getter is usually composed mainly of Ba or the like, and maintains the atmosphere in the envelope 88 by the adsorption action of the deposited film.

Next, an example of the configuration of a drive circuit for performing television display based on an NTSC television signal on a display panel configured using electron sources arranged in a simple matrix arrangement will be described with reference to FIG. . In FIG.
Reference numeral 101 denotes an image display panel, which corresponds to the envelope 88. 102 is a scanning circuit, 103 is a control circuit, and 104 is a shift register. 105 is a line memory, 106 is a synchronization signal separation circuit, 107 is a modulation signal generator, and Vx and Va are DC voltage sources. 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 Hv. Terminal D
ox1 to Doxm are provided for sequentially driving electron sources provided in the display panel, that is, a group of surface conduction electron-emitting devices arranged in a matrix of M rows and N columns, one row (N element) at a time. A scanning signal is applied. To the terminals Dy1 to Dyn, a modulation signal for controlling an output electron beam of each element of the surface conduction electron-emitting device in one row selected by the scanning signal is applied. A DC voltage source V is connected to the high voltage terminal Hv.
From a, a DC voltage of, for example, 10 kV 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. The scanning circuit 102 will be described.
This circuit includes M switching elements inside (in the drawing, S1 to Sm are schematically shown).
Each switching element selects either the output voltage of the DC voltage source Vx or 0 V (ground level),
It is electrically connected to terminals Dx1 to Dxm of the display panel 101. Each of the switching elements S1 to Sm operates based on the control signal Tscan output from the control circuit 103, 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 electron-emitting element. It is set to output a constant voltage that is equal to or lower than the voltage. The control circuit 103 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. Control circuit 103
Is the synchronization signal Ts sent from the synchronization signal separation circuit 106.
Tscan and Ts for each part based on the sync
ft and Tmry control signals are generated. The synchronization signal separating circuit 106 is a circuit for separating a synchronization signal component and a luminance signal component from an NTSC television signal input from the outside. The synchronizing signal separated by the synchronizing signal separating circuit 106 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 104.

The shift register 104 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 103. (Ie, the control signal Tsft can be said to be a shift clock of the shift register 104). The data for one line of the image subjected to the serial / parallel conversion (corresponding to drive data for N electron-emitting devices) is output from the shift register 104 as N parallel signals Id1 to Idn.

The line memory 105 is a storage device for storing data for one line of an image for a required time only, and stores the contents of Id1 to Idn as appropriate according to a control signal Tmry sent from the control circuit 103. The stored contents are output as I'd1 to I'dn and input to the modulation signal generator 107. Modulation signal generator 107
Is a signal source for appropriately driving and modulating each of the surface conduction electron-emitting devices in accordance with each of the image data I'd1 to I'dn, and the output signal thereof is supplied to terminals Doy1 to Doyn.
Is applied to the surface conduction electron-emitting device in the display panel 101.

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, a clear threshold voltage Vth is required for electron emission.
And electron emission occurs only when a voltage 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 applying a pulsed voltage to this element,
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, an electron beam is output. At this time, the pulse peak value V
By changing m, the intensity of the output electron beam can be controlled. In addition, it is possible to control the total amount of charges of the output electron beam by changing the pulse width Pw. Therefore, according to the input signal,
As a method of modulating the electron-emitting device, a voltage modulation method,
A pulse width modulation method or the like can be adopted. 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 107. be able to.

When implementing the pulse width modulation method,
As the modulation signal generator 107, 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. Shift register 104 and line memory 1
05 can use 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 separation circuit 106 into a digital signal. For this purpose, an A / D converter may be provided at the output section of the synchronization signal 106. In connection with this, the line memory 10
Depending on whether the output signal of 5 is a digital signal or an analog signal,
The circuit used for modulation signal generator 107 is slightly different. That is, in the case of the voltage modulation method using a digital signal, for example, a D / A conversion circuit is used as the modulation signal generator 107, and an amplification circuit and the like are 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 for counting the number of waves output from the oscillator, and a comparator for comparing the output value of the counter with the output value of the memory. (Comparator) 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, an amplification circuit using, for example, an operational amplifier can be used as the modulation signal generator 107, and a level shift circuit and the like can be added as necessary. In the case of the pulse width modulation method, for example, a voltage-controlled oscillation circuit (VOC) 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 apparatus to which the present invention can be applied, the electron emission is generated by applying a voltage to each electron-emitting device via the external terminals Dox1 to Doxm and Doy1 to Doyn. Metal back 85 via high voltage terminal Hv or transparent electrode (not shown)
To apply a high voltage to accelerate the electron beam. The accelerated electrons collide with the fluorescent film 84 and emit light to form an image.

Next, a ladder-type arrangement of the electron source and the image forming apparatus will be described with reference to FIGS.

FIG. 13 is a schematic diagram showing an example of a ladder-type arrangement of electron sources. In FIG. 13, reference numeral 110 denotes an electron source substrate, and 74 denotes an electron-emitting device. 112, Dx1 to Dx10
Is a common wiring for connecting the electron-emitting devices 74. A plurality of electron-emitting devices 74 are arranged on the substrate 110 in parallel in the X direction (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 D between each element row
For x2 to Dx9, for example, Dx2 and Dx3 can be the same wiring.

FIG. 14 is a schematic diagram showing an example of a panel structure in an image forming apparatus having a ladder-type electron source. Reference numeral 120 denotes a grid electrode, 121 denotes a hole through which electrons pass, and 122 denotes an external terminal made of Dox1, Dox2,..., Doxm. Reference numeral 123 denotes an external terminal composed of G1, G2,... Gn connected to the grid electrode 120;
Reference numeral 24 denotes an electron source substrate in which the common wiring between the elements is the same wiring. In FIG. 14, the same portions as those shown in FIGS. 8 and 13 are denoted by the same reference numerals as those shown in these drawings. A major difference between the image forming apparatus shown here and the image forming apparatus having the simple matrix arrangement shown in FIG. 8 is whether or not a grid electrode 120 is provided between the electron source substrate 110 and the face plate 86. In FIG. 14, a grid electrode 120 is provided between the substrate 110 and the face plate 86. The grid electrode 120 is for modulating the electron beam emitted from the surface conduction electron-emitting device, and allows the electron beam to pass through a stripe-shaped electrode provided orthogonally to the ladder-type arrangement element row. One circular opening 121 is provided for each 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 a mesh shape as openings, and a grid may be provided around or near the surface conduction electron-emitting device. The outer container terminal 122 and the outer grid container terminal 123 are electrically connected to a control circuit (not shown). In the image forming apparatus of the present embodiment, a modulation signal for one line of an image is simultaneously applied to the grid electrode columns 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 configuration of the image forming apparatus described here can be variously modified based on the technical idea of the present invention. As for the input signal, the NTSC system has been described, but the input signal is not limited to this. For example, a PAL or SECAM system or a TV signal (for example, a high-definition TV) comprising a larger number of scanning lines than this is used. Can also be adopted.

The image forming apparatus of the present invention can be used not only as a display device for television broadcasting, a display device such as a video conference system or a computer, but also as an image forming device as an optical printer using a photosensitive drum or the like. Can be used.

[0071]

EXAMPLES Hereinafter, the present invention will be described in detail 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 The basic structure of a surface conduction type electronic device according to the present invention is the same as that shown in FIG.

Hereinafter, the basic structure and manufacturing method of the device according to the present invention will be described with reference to FIG.

In FIG. 1, 1 is a substrate, 2 and 3 are device electrodes, 4 is a conductive fine particle film, 5 is an electron-emitting portion, 6 is a subbing film, and 7 is bismuth oxide particles.

Hereinafter, the manufacturing method will be described in order with reference to FIG.

1) Using a soda lime glass as the substrate 1, after degreasing and washing, an ethylenediaminetetraacetic acid-bismuth (E) was added to a SiO ₂ fluid coating agent (OCD manufactured by Tokyo Ohka Kogyo Co., Ltd.).
The solution to which the (DTA-Bi complex) aqueous solution was added was spin-coated with a spinner. Then bake at 400 ° C for 1 hour,
A subbing film 6 having a thickness of about 1000 Å was formed.

2) Device electrodes 2 and 3 were formed on the surface of the substrate 1. Any material may be used as the material of the device electrode, as long as it has conductivity. In this embodiment, the material is Ti / Ni, and the film thickness is Ti.
/ Ni = 5/00 nm. The electrode spacing was 5 μm.

3) A Cr film having a thickness of 100 nm is provided in a place where fine particles are not to be formed, and thereafter, organic palladium (CCP4230 manufactured by Okuno Pharmaceutical Co., Ltd.) is spin-coated with a spinner at 300 ° C.
The heating and firing were performed for -20 minutes. Thereafter, the Cr mask was removed by an etchant to form a desired conductive fine particle film 4.

4) Next, a voltage was applied between the device electrodes 2 and 3 in a vacuum vessel, and the conductive fine particle film 4 was subjected to an energizing process (forming process) to produce an electron-emitting portion 5. FIG. 4 shows a voltage waveform of the forming process. In this embodiment, the pulse width T ₁ of the voltage waveform is 1 millisecond, and T ₂ is 10
In milliseconds, the peak value of the triangular wave (peak voltage during forming) is gradually increased, and the forming process is performed at about 1 × 10 ⁻⁶ T
This was performed under a vacuum atmosphere of orr. The forming process was terminated when the measured value of the resistance measurement pulse became about 1 MΩ or more, and the application of the voltage to the element was terminated at the same time.

5) The electron emission characteristics of the device manufactured as described above were measured. A device voltage is applied between the electrodes 2 and 3 of the electron-emitting device, and a device current If,
When the emission current Ie was measured, If was 1 mA and Ie was 0.5 μA, and the electron emission efficiency η = Ie / If (%)
Was 0.05%.

The device thus fabricated was compared with Bi for comparison.
Electrical resistance to heat was measured for the element having a subbing film containing no O. The measurement was H ₂ / N ₂ = 2% / 98
The measurement was performed by measuring the electric resistance value while heating the element under an atmospheric pressure reducing atmosphere in a% mixed gas. FIG. 1 shows the results of measuring the electrical heat-resistant temperatures of these conductive thin films.
It is shown in FIG.

As is apparent from FIG. 15, the phenomenon of the change in the electric resistance value due to the temperature change is as follows. First, at room temperature, the reduction of PdO → Pd in the reducing atmosphere proceeds, so that the electric resistance value decreases. Thereafter, a slight increase in the electrical resistance value due to the temperature characteristics of the metal continues. At a certain temperature or higher, the electrical resistance value sharply increases due to a phenomenon considered to be aggregation of the conductive thin film.

Referring to FIG. 15, the temperature at which the electric resistance value suddenly starts to increase is higher in the element to which Bi is added. That is, it was shown that the electrical heat resistance temperature was high.

[Example 2] On the undercoat film obtained in the same manner as in Example 1, and on the quartz substrate 1 on which the device electrodes 2 and 3 were formed, a conductive film made of Pt was formed in the same manner as in Example 1. A fine particle film 6 was formed.

Further, an electron emitting portion 5 was formed by performing the same forming process as in the first embodiment.

The device thus fabricated was compared with Bi as a comparison.
Electrical resistance to heat was measured in the same manner as in Example 1 for an element having an undercoat film containing no O, and the same effect as in Example 1 was obtained.

Example 3 A conductive film made of Pt was formed on a quartz substrate 1 on which an under electrode film and an element electrode 2 and 3 were formed in the same manner as in Example 1. A fine particle film 6 was formed. Further, by performing the same forming processing as in Example 1, it was confirmed that electron emission was observed. Instead of the anode electrode 54, a face plate having the above-described fluorescent film and metal back was arranged in a vacuum device. When the electron emission from the electron source was attempted in this way, a part of the fluorescent film emitted light, and the intensity of light emission changed according to the device current Ie. Thus, it was found that this element functions as a light-emitting display element.

[Embodiment 4] A rear plate 81, a support frame 82, and a face plate 86 are connected to an electron source in which a plurality of electron-emitting devices obtained in the same manner as in Embodiment 1 are formed in a matrix, and a vacuum is applied. After sealing, the image forming apparatus shown in FIG. 9 was manufactured. Display was performed using the driving circuit shown in FIG. 10 according to an NTSC television signal.

In the present display device, in particular, it is easy to reduce the thickness of a display panel using a surface conduction electron-emitting device as an electron beam source, so that the depth of the display device can be reduced. In addition, the display panel using a surface conduction electron-emitting device as an electron beam source is easy to enlarge the screen, has high brightness, and has excellent viewing angle characteristics, so this display device is full of a sense of reality and full of power. Images can be displayed with good visibility.

The display device of this embodiment was able to display a television image according to the NTSC television signal in a favorable and stable manner.

[0091]

As described above, the provision of the undercoating film containing bismuth oxide on at least the surface in contact with the conductive thin film 4 makes it possible to increase the electrical heat resistance temperature. Restrictions can be relaxed. Specifically, the organic material in the container can be evacuated by heating the vacuum container to near the heat resistance in the stabilization step when manufacturing the element or when manufacturing the image forming apparatus.

Therefore, the manufacturing cost can be reduced by omitting the temperature control and the steps which are limited by the heat-resistant temperature of the element, and the stabilization of the element characteristics and the long life due to the high baking (heating) temperature can be achieved. Also has the effect.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing a configuration of a surface conduction electron-emitting device according to an embodiment and an example of the present invention.

FIG. 2 is a schematic diagram illustrating a configuration of a vertical surface conduction electron-emitting device according to an embodiment of the present invention.

FIG. 3 is a schematic view illustrating a method of manufacturing a surface conduction electron-emitting device according to embodiments and examples of the present invention.

FIG. 4 is a schematic diagram showing an example of a voltage waveform in an energization forming process that can be employed in manufacturing a surface conduction electron-emitting device according to an embodiment and an example of the present invention.

FIG. 5 is a schematic diagram illustrating an example of a vacuum processing apparatus having a measurement evaluation function.

FIG. 6 is a graph showing an example of the relationship between the emission current Ie, the device current If, and the device voltage Vf for the surface conduction electron-emitting device according to the embodiment and the example of the present invention.

FIG. 7 is a schematic view showing an electron source arranged in a simple matrix according to the embodiment and the example of the present invention.

FIG. 8 is a schematic diagram illustrating a display panel of an image forming apparatus according to an embodiment and an example of the present invention.

FIG. 9 is a schematic diagram illustrating an example of a fluorescent film.

FIG. 10 is a block diagram illustrating an example of a driving circuit for performing display in the image forming apparatus in accordance with an NTSC television signal.

FIG. 11 is a conceptual diagram of an apparatus for manufacturing an image forming apparatus according to an embodiment of the present invention.

FIG. 12 is a conceptual diagram of an apparatus for forming according to an embodiment of the present invention.

FIG. 13 is a schematic diagram illustrating an example of an electron source having a ladder arrangement according to an embodiment of the present invention.

FIG. 14 is a schematic diagram illustrating an example of a display panel of the image forming apparatus according to the embodiment of the present invention.

FIG. 15 is a graph showing an example of the electrical withstand temperature of the surface conduction electron-emitting device of the present invention and a conventional surface conduction electron-emitting device.

FIG. 16 is a schematic view showing an example of a conventional 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 6 Undercoat film 7 Bismuth oxide particles 21 Step formation part 50 Current for measuring device current If flowing through conductive thin film 4 between device electrodes 2 and 3 A total of 51 A power supply for applying the device voltage Vf to the electron-emitting device 53 A high-voltage power supply for applying a voltage to the anode electrode 54 An anode electrode 55 for capturing the emission current Ie emitted from the electron-emitting portion of the device 55 A device Emission current Ie emitted from the electron emission portion 5
56 Vacuum device 57 Exhaust pump 71 Electron source substrate 72 X-directional wiring 73 Y-directional wiring 74 Surface conduction electron-emitting device 75 Connection 81 Rear plate 82 Support frame 83 Glass substrate 84 Fluorescent film 85 Metal back 86 Face plate 87 High voltage terminal 88 Envelope 91 Black conductive material 92 Phosphor 93 Glass substrate 101 Display panel 102 Scanning circuit 103 Control circuit 104 Shift register 105 Line memory 106 Synchronization signal separation circuit 107 Modulation signal generator Vx and Va DC voltage source 110 Electron source substrate 112 Dx1 to Dx10 are connected to the common wiring for wiring the electron-emitting devices 120 Grid electrode 121 Holes 122 for passing electrons 122 Doxm outside terminals 123 Doxm Connected to grid electrode 120 G1 G2

Claims (6)

[Claims] 1. An electron-emitting device in which a pair of device electrodes and a conductive thin film having an electron-emitting portion between the device electrodes are formed on a substrate, wherein the conductive thin film is made of a platinum group element. An electron-emitting device comprising an undercoat film containing SiO ₂ as a main component and containing bismuth oxide particles on at least a surface in contact with the conductive thin film. 2. The electron-emitting device according to claim 1, wherein the platinum group element is Pd. 3. The bismuth oxide particles present on the surface in contact with the conductive thin film out of the bismuth oxide particles contained in the undercoat film, wherein the total metal contained in the conductive thin film is 100 mol%. 3. The electron-emitting device according to claim 1, wherein the content is in a range of 1 to 10 mol%. 4. A device comprising a plurality of electron-emitting devices according to claim 1, further comprising a modulating means for modulating an electron beam emitted from said plurality of electron-emitting devices in accordance with an information signal. An electron source, comprising: 5. An image forming apparatus comprising the electron source according to claim 4. 6. A method for manufacturing an electron-emitting device in which a pair of device electrodes and a conductive thin film having an electron-emitting portion between the device electrodes are formed on a substrate, wherein the device is in contact with at least the conductive thin film on the substrate. A method for manufacturing an electron-emitting device, comprising a step of forming a subbing film containing SiO ₂ as a main component and containing bismuth oxide particles on a surface to be formed.