JP2000123718A - Electron emitting element, electron source, image forming device, and their manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably manufacture an election emitting element having high efficiency of electron emission capable of realizing a high-performance image forming device having high brightness and excellent operational stability. SOLUTION: In this manufacturing method for the electron emitting element having a conductive film including an electron emitting part between a pair of element electrodes, cracks are formed in the conductive film, thereafter pulse voltage is impressed between the element electrodes in the atmosphere including an organic material such that the length (T10-T1N) of the pulse voltage impressing time is increased gradually to the length of the non-impressing time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron-emitting device, an electron source having a large number of such electron-emitting devices, and an image forming apparatus such as a display device or an exposure device using the electron source.
And their production methods.

[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 devices include 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 electron-emitting device, and the like. .

[0003] As an example of the FE type, W. P. Dyke
and W. W. Dolan, "Field Em
issue ", Advance in Elect
ron Physics, 8, 89 (1956) or C.I. A. Spindt, “Physical
Properties of thin-filmfi
eld emission cathodes wit
h molybdenum cones ", JA
ppl. Phys. , 47, 5248 (1976).
And the like are known.

As an example of the MIM type, C.I. A. Mea
d, “Operation of Tunnel-Em
issue Devices ", J. Appl.
Phys. , 32, 646 (1961).

As an example of the surface conduction electron-emitting device,
M. I. Elinson, Radio Eng.
Electron Phys. , 10, 1290 (1
965).

[0006] The surface conduction electron-emitting device utilizes the phenomenon that electron emission occurs when a current flows through 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 Fi
lms ", 9,317 (1972)] , In 2 O 3 /
According to SnO ₂ thin film [M. Hartwell an
d C.I. G. FIG. Fonstad: “IEEE Tran
s. ED Conf. ", 519 (1975)],
By carbon thin film [Hisashi Araki et al .: Vacuum, 26th
Vol. 1, No. 22, p. 22 (1983)].

As a typical example of these surface conduction electron-emitting devices, the above-mentioned M.P. Figure 2 shows the device configuration of Hartwell
FIG. In FIG. 1, reference numeral 1 denotes a substrate. Reference numeral 4 denotes a conductive film, which is formed of a metal oxide thin film or the like formed in an H-shaped pattern. The electron emission portion 5 is formed by an energization process called energization forming described later. In the drawing, the element electrode interval L is 0.5 to 1 mm, and W ′ is 0.1 m.
m.

In these surface conduction electron-emitting devices, it is general that the electron-emitting portion 5 is formed beforehand by performing an energization process called energization forming on the conductive film 4 before electron emission. That is, the energization forming is to apply a DC voltage or a very slowly increasing voltage, for example, about 1 V / min, to both ends of the conductive film 4 and to energize the conductive film 4 to locally destroy, deform or deteriorate the conductive film 4. This is a process of changing the structure and forming the electron-emitting portion 5 in an electrically high-resistance state. Note that a crack is generated in a part of the conductive film 4 in the electron emitting portion 5, and electrons are emitted from the vicinity of the crack.

Furthermore, the present applicant has noticed that the current flowing through the above-mentioned conductive film (hereinafter referred to as "device current") and the current discharged into vacuum (hereinafter referred to as "emission current") are significantly changed. (Japanese Unexamined Patent Publication No.
235255).

The above-mentioned surface conduction type electron-emitting device has an advantage that, since the structure is simple, it is easy to form an electron source in which a large number of devices are arranged in a matrix or the like over a large area. . Various applications for utilizing this feature are being studied, for example, application to an image forming apparatus such as a self-luminous thin image display apparatus. When an activation step is performed on such an electron source, for example, a pulse voltage is simultaneously applied to elements belonging to the same row under an appropriate atmosphere, or a pulse voltage is sequentially applied to each element, and a film of an activation material is applied. Is deposited.

Meanwhile, electron emitters used in an electron source of an image forming apparatus or the like are required to have more uniform electron emission characteristics and improved electron emission efficiency so that a bright display image can be stably provided. Here, the electron emission efficiency is represented by the ratio of the device current to the emission current, and an electron emission device having a small device current and a large emission current is desired.

If the electron emission characteristics and efficiency which can be controlled stably are further improved, for example, in an image forming apparatus using a phosphor as an image forming member, a high-quality image forming apparatus with a low current and a high brightness can be used. For example, a flat television is realized. Further, as the current is reduced, the cost of a drive circuit and the like constituting the image forming apparatus can be reduced.

[0013]

However, in the activation treatment step which is a part of the conventional step of manufacturing the surface conduction electron-emitting device, there is a problem of uniformity of the conductive film used.
In addition, due to the problem of adhesion between the substrate and the conductive film or the like, a portion (inactive region) that does not contribute to electron emission may be generated depending on how the activation condition is applied. If a surface conduction electron-emitting device having such a large proportion of inactive regions is formed, it is not always possible to obtain stable electron emission characteristics and electron emission efficiencies. Therefore, it is difficult to realize an image forming apparatus having excellent operation stability.

An object of the present invention is to solve the above-mentioned technical problems to be solved, and to provide an electron-emitting device having stable electron emission characteristics and improving electron emission efficiency. Another object of the present invention is to provide an image forming apparatus which uses a plurality of such electron-emitting devices and has high luminance and excellent operation stability.

[0015]

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, a first aspect of the present invention is a method for manufacturing an electron-emitting device having a conductive film including an electron-emitting portion between a pair of electrodes on a substrate. And an activation step of repeatedly applying a pulse voltage between the electrodes in an atmosphere containing an organic substance, wherein the length of the pulse voltage application time in the activation step is longer than the length of the non-application time. In the method of manufacturing an electron-emitting device.

The first feature of the present invention is that, as a further feature, "the length of the application time of the pulse voltage in the activation step is gradually increased stepwise with respect to the length of the non-application time". The step value gradually increases the peak value of the pulse voltage in the activation step.

According to a second aspect of the present invention, there is provided a method of manufacturing an electron-emitting device having a conductive film including an electron-emitting portion between a pair of electrodes on a substrate, wherein a forming step of forming the electron-emitting portion in the conductive film is provided. An activation step of repeatedly applying a pulse voltage between the electrodes in an atmosphere containing an organic substance, wherein a voltage lower than a threshold value of an element voltage with respect to an element current within a non-application time of the pulse voltage in the activation step. In a method for manufacturing an electron-emitting device.

The second feature of the present invention is that a DC voltage lower than a threshold of an element voltage with respect to an element current is applied within a non-application time of a pulse voltage in the activation step. Within the non-application time of the pulse voltage in the activation step, an AC voltage whose amplitude is lower than the threshold of the element voltage with respect to the element current is applied ”, and“ the non-application time of the pulse voltage in the activation step or the The half period is longer than the average residence time of the organic substance gas molecules on the substrate surface. "

A third aspect of the present invention resides in an electron-emitting device manufactured by the first or second method of the present invention.

According to a fourth aspect of the present invention, there is provided a method of manufacturing an electron source in which a plurality of electron-emitting devices having a conductive film including a pair of electrodes and an electron-emitting portion are arranged on a substrate. And a method of manufacturing an electron source characterized by being manufactured by the first or second method of the present invention.

According to a fifth aspect of the present invention, there is provided an electron source manufactured by the above-mentioned fourth method of the present invention.

According to a sixth aspect of the present invention, there is provided an electron source in which a plurality of electron-emitting devices having a conductive film including a pair of electrodes and an electron-emitting portion are arranged on a substrate, and irradiation of an electron beam emitted from the electron source. A method for manufacturing an image forming apparatus having an image forming member for forming an image according to the present invention, wherein the electron source is manufactured by the above-described fourth method of the present invention.

According to a seventh aspect of the present invention, there is provided an image forming apparatus manufactured by the sixth method of the present invention.

[0025]

According to the first manufacturing method of the present invention, the power of the pulse applied in the early stage of activation is reduced to prevent damage due to heat generation (expansion of cracks in the conductive film) and to reduce the carbon film to cracks. Formed on the inside, after the protective effect of the carbon film appears, the power is increased and the carbon film is sufficiently deposited. Thereby, it is possible to suppress the occurrence of a portion (inactive region) that does not contribute to electron emission due to cracks expanding.

According to the second manufacturing method of the present invention, a conductive deposit is formed in a crack by a bias equal to or lower than the threshold voltage, even if it does not directly contribute to electron emission. Thereby, even in a wide portion of a crack formed by forming, activation can be performed, deposition of carbon contributing to electron emission progresses, and generation of a portion (inactive region) not contributing to electron emission is suppressed. Can be.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic structure of an electron-emitting device to which the present invention can be applied is roughly classified into two types: a planar type and a vertical type. First, a flat-type electron-emitting device will be described.

FIG. 1 is a schematic view showing an example of the configuration of a flat type electron-emitting device according to the present invention. FIG. 1 (a) is a plan view and FIG. 1 (b) is a cross-sectional view. In FIG. 1, 1 is a substrate, 2
And 3 are electrodes (device electrodes), 4 is a conductive film, and 5 is an electron emitting portion.

As the substrate 1, quartz glass, glass having a reduced impurity content such as Na, blue plate glass, a glass substrate on which SiO ₂ is laminated by sputtering or the like, ceramics such as alumina, and a Si substrate can be used. it can.

The materials of the opposing device electrodes 2 and 3 are as follows.
General conductor materials can be used, for example, Ni, C
Metals or alloys such as r, Au, Mo, W, Pt, Ti, Al, Cu, Pd and Pd, Ag, Au, RuO ₂ , Pd
Metal or metal oxides and glass or the like printed conductor composed of such -ag, can be appropriately selected from an In ₂ O ₃ -SnO transparent conductor ₂ and the like and a semiconductor conductive material such as polysilicon.

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

In addition to the configuration shown in FIG. 1, a configuration in which a conductive film 4 and device electrodes 2 and 3 facing each other are formed on a substrate 1 in this order can be adopted.

As a material constituting the conductive film 4, for example, Pd, Pt, Ru, Ag, Au, Ti, In, Cu,
Metals such as Cr, Fe, Zn, Sn, Ta, W, and Pb;
oxides such as dO, SnO ₂ , In ₂ O ₃ , PbO, Sb ₂ O ₃ , HfB ₂ , ZrB ₂ , LaB ₆ , CeB ₆ , Y
Borides such as B ₄ and GdB ₄ , TiC, ZrC, HfC,
Carbides such as TaC, SiC, WC, TiN, ZrN, H
It is appropriately selected from nitrides such as fN, semiconductors such as Si and Ge, and carbon.

As the conductive 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 to 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 set, and more preferably, the range is set to 1 nm to 50 nm. As for the resistance value, Rs is preferably a value of 10 ² Ω to 10 ⁷ Ω. Note that Rs is a value that appears when a resistance R measured in the length direction of a thin film having a width w and a length 1 is set as R = Rs (l / w).

The fine particle film described here is a film in which a plurality of fine particles are gathered. The fine structure is not only a state in which the fine particles are individually dispersed and arranged, but also a state in which the fine particles are adjacent to each other or overlapped (some). Particles gather,
(Including the case where an island structure is formed as a whole). The particle size of the fine particles is in the range of several to several hundreds of nm, preferably in the range of 1 to 20 nm.

It should be noted that the term "fine particles" is frequently used in this specification, and its meaning will be described.

Small particles are called "fine particles", and smaller ones are called "ultra fine particles". Particles smaller than "ultrafine particles" and having a few hundred atoms or less are widely called "clusters".

However, each boundary is not strict and varies 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.

For example, in “Experimental Physics Course 14: Surfaces and Particles” (edited by Yoshio Kinoshita, published on September 1, 1986 by Kyoritsu Publishing Co., Ltd.) And especially when it is referred to as ultrafine particles, the particle size is about 10 nm to 2-3 n.
It means up to about m. 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. (Page 195, lines 22 to 26).

In addition, the definition of “ultrafine particles” in the “Hayashi / Ultrafine Particle Project” of the New Technology Development Corporation was that the lower limit of the particle size was even smaller, as follows.

In the "Ultra Fine Particle Project" of the Creative Science and Technology Promotion System (1981 to 1986), a particle having a size (diameter) in the range of about 1 to 100 nm is called an "ultra fine particle". Then, one ultrafine particle is about 100-
It is an aggregate of about 10 ⁸ atoms. Ultra-fine particles are large to giant particles on an atomic scale. ("Ultra Fine Particles-Creative Science and Technology" Hayashi Tax, Ryoji Ueda, Akira Tazaki
(Edited by Mita Publishing, 1988, page 2, lines 1 to 4) /
"A particle even smaller than an ultrafine particle, that is, a single particle composed of several to several hundred atoms, is usually called a cluster" (ibid., Page 2, lines 12 to 13).

[0042] Based on the general notation as described above,
In the present specification, “fine particles” are an aggregate of a large number of atoms and molecules, and the lower limit of the particle size is several Å to 1 nm and the upper limit is several μm
It refers to the degree.

The electron-emitting portion 5 is constituted by a high-resistance crack formed in a part of the conductive film 4 and depends on the film thickness and material of the conductive film 4 and the energization forming and activation steps to be described later. It will be. In some cases, conductive fine particles having a particle size in the range of several 数 to several tens of 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 film 4. The conductive film 4 at the tip of the crack and in the vicinity thereof has a film containing carbon. The film containing carbon is, for example, graphite (what includes so-called HOPG, PG, and GC; HOPG has a substantially complete graphite crystal structure, PG has a crystal grain of about 200 ° and has a slightly disordered crystal structure, and GC has a crystal structure. A grain having a diameter of about 20 nm and disorder of the crystal structure are further increased.), And amorphous carbon (refers to amorphous carbon and a mixture of amorphous carbon and the fine crystals of graphite).
The thickness is preferably in the range of 500 ° or less, more preferably in the range of 300 ° or less.

Next, a vertical type electron-emitting device will be described.

FIG. 2 is a schematic view showing an example of the structure of a vertical type electron-emitting device to which the present invention can be applied. The same parts as those shown in FIG. Signs are attached. 21 is a step forming part. The substrate 1, the device electrodes 2, 3, the conductive film 4, and the electron-emitting portion 5 can be made of the same material as that of the above-described flat-type electron-emitting device. The step forming portion 21 can be made of an insulating material such as SiO ₂ formed by a vacuum deposition method, a printing method, 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-type electron-emitting device described above, and can be in a 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 21 and the voltage applied between the device electrodes 2 and 3, and is preferably in the range of several tens nm to several μm.

The conductive film 4 is laminated on the device electrodes 2 and 3 after the device electrodes 2 and 3 and the step forming portion 21 are formed. In FIG. 2, the electron emitting section 5 includes a step forming section 21.
However, the shape and position are not limited to these depending on forming conditions and the like described later.

There are various methods for manufacturing the electron-emitting device of the present invention. One example will be described with reference to FIG. In FIG. 3, the same parts as those shown in FIG. 1 are denoted by the same reference numerals as those shown in FIG.

Step-A: Step of Forming Element Electrode The substrate 1 is sufficiently washed with a detergent, pure water, and an organic solvent, and an element electrode material is deposited by a vacuum evaporation method, a sputtering method, or the like, and then, for example, by using a photolithography technique. Substrate 1
The device electrodes 2 and 3 are formed thereon (FIG. 3A).

Step-B: Step of Forming Conductive Film An organic metal solution is applied on the substrate 1 provided with the device electrodes 2 and 3 to form an organic metal thin film. Organometallic solutions include:
A solution of a metal complex containing a metal as a main element of the material of the conductive film 4 described above 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 film 4 having a desired shape (FIG. 3).
(B)). Here, the organic metal solution coating / firing method has been described, but the conductive film 4 may be formed by a vacuum deposition method, a sputtering method, a chemical vapor deposition method, a dispersion coating method, a dipping method, a spinner method, or the like. Can be used.

Step-C: Forming Step 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 current is applied between the device electrodes 2 and 3, an electron emitting portion 5 composed of a high-resistance crack having a changed structure is formed in a part of the conductive film 4 (FIG. 3C).

FIG. 4 shows an example of the voltage waveform of the energization forming. The voltage waveform of the energization forming is particularly 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 pulse is applied while increasing the pulse peak value are used.
There is a method shown in

In FIG. 4A, T ₁ and T ₂ are the pulse width and pulse interval of the voltage waveform. Normal T ₁ is 1μ second to
10 ms and T ₂ are set in the range of 10 μs to 100 ms. The peak value (peak voltage) of the triangular wave is appropriately selected according to the form of the 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.
It can be similar to that shown in FIG. The peak value (peak voltage) of the triangular wave can be increased, for example, in steps of about 0.1 V.

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

Step-D: Activation Step A device called an activation step is applied to the formed element. The activation process is a process in which the device current _If and the emission current _Ie are significantly changed by this process.

The activation step can be performed, for example, by repeatedly applying a pulse between the device electrodes 2 and 3 in an atmosphere containing an organic substance gas, 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 form of the above-described element, 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, ketones, amines, phenols, carboxyls, organic acids such as sulfonic acids, and the like,
Specifically, C _n H _{2n + 2} such as methane, ethane, and propane
C such as saturated hydrocarbon, ethylene, propylene represented by
_n H _2n unsaturated hydrocarbon expressed by a composition formula such as, benzene, toluene, methanol, ethanol, formaldehyde, acetaldehyde, acetone, methyl ethyl ketone, methylamine, ethylamine, phenol, formic acid,
Acetic acid, propionic acid and the like can be used.

By this activation 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 greatest feature of the present invention lies in the method of applying a voltage in the activation step, which will be described in detail below.

The first manufacturing method of the present invention is characterized in that the length of the application time of the pulse voltage repeatedly applied between the device electrodes in the activation step is changed with respect to the length of the non-application time. Yes, specifically, for example, it can be performed while gradually increasing the length of the application time of the pulse voltage with respect to the length of the non-application time.

For example, as shown in FIG.
_0, the pulse period T ₂ is constant, from a very short value T ₁₀ the pulse width is increased to approximately the pulse width used during the forming. As an example of the pulse width increasing rate, the pulse width T ₁₀ = 1 μsec in the first 30 seconds, the pulse interval T ₂ = 10 ms, and the pulse width T ₁₁ = 5 μ in the next 30 seconds.
It can be gradually increased stepwise with time, for example, seconds and pulse interval T ₂ = 10 ms.

As described above, by applying a pulse voltage having a very short pulse width in the early stage of activation, a stable carbon is formed inside the crack formed in the conductive film 4 in the forming step in the early stage of activation. Can be immobilized. If a film containing stable carbon is formed in the early stage of the activation as described above, it is possible to minimize the regression of the crack (expansion of the crack width) seen in the early stage of the conventional activation process, and thereafter, By increasing the pulse width, the film containing carbon can be fixed so as to reduce the crack width over the entire length of the crack. Therefore, generation of a region (inactive region) that does not control electron emission can be suppressed as much as possible. The voltage waveform of the activation pulse is preferably a rectangular or triangular pulse waveform, like the forming voltage.

[0062] In the second manufacturing method of the present invention, during the non-application time of the pulse voltage in the activation step, the direct current having the voltage lower than the threshold value of the device voltage with respect to the device current,
Another feature is that an AC voltage is applied, whereby a narrow crack can be stably formed. This will be described in detail with reference to FIGS.

The above activation step microscopically utilizes the following phenomena. Sufficient electron emission cannot be obtained only by the crack (100 ° order) formed in the conductive film 4 by the forming process. When exposed to the above-described organic gas atmosphere in this state, gas molecules are adsorbed in the cracks (see FIG. 6B). The amount of adsorption is determined by the gas pressure, the substrate temperature, the number of adsorption sites on the substrate, the average staying time of the adsorbed molecules, and the adsorption probability. In this state, a voltage _Vf between the device electrodes 2 and 3 that is equal to or higher than the threshold value _{Vth of the} device voltage with respect to the device current (FIG. 6A)
), Electrons are emitted from the crack cathode side,
The emitted electrons collide with the adsorbed molecules in the crack, and are decomposed and fixed (see FIG. 6C). Next, when the voltage is turned off, gas molecules are adsorbed again in the crack. Like this constant on
By repeatedly applying a pulse voltage having a time (application time) and an off time (non-application time), conductive carbon or a carbon compound can be deposited in the crack. As a result, the crack width is further narrowed, the electric field intensity is increased, and the electron emission efficiency can be improved.

However, according to the research of the present inventor,
Similar to the energization forming, it has been found that the following problems exist in the conventional activation process in which the application of the pulse voltage is simply repeated. That is, gas molecules are adsorbed at sites uniformly distributed in the crack during the off time, but once adsorbed molecules do not have the energy necessary for surface diffusion, and are fixed to the adsorption sites and hardly move. . Then on-time electrons are emitted from the crack cathode side,
The adsorbed molecules are decomposed and fixed. As a result, a fine particle film of carbon or carbon compound uniformly distributed as shown in FIG. 6C is easily deposited in the crack, and a sufficiently narrow crack in which an electric field is concentrated is not formed, and electron emission is not performed. Efficiency will not increase much.

On the other hand, in the second manufacturing method of the present invention, by applying a voltage lower than the threshold of the device voltage to the device current during the off time of the activation step, the diffusion of the adsorbed gas molecules is promoted, and the electric field is reduced. A sufficiently narrow crack where concentration occurs can be stably formed.

That is, a state in which a voltage lower than the threshold of the element voltage with respect to the element current is applied during the off time (a state in which the film current _If does not flow and only the electric field is applied in the crack).
When the gas molecules are adsorbed in the cracks, a uniform force F acts on the permanent dipole moment (or induced dipole moment) of the adsorbed molecules (see FIG. 7B). This force F
Acts only on the adsorbed molecules in the crack, and as shown in FIG. 7B, when the adsorbed molecules move to the crack end, the force F disappears. Next, when the ON time is reached, electron emission occurs, which collides with the adsorbed molecules to be decomposed and fixed.
Does not move even if it works, and as a result, on time /
As shown in FIG. 7C, the crack width is reduced as shown in FIG. 7C for each cycle of the off time, and the electric field intensity is increased to improve the electron emission efficiency.

What matters here is the length of the off time. It is estimated that the time required for gas molecules to be adsorbed into the crack and to move to the crack end is on the order of the average residence time of the adsorbed molecules. Therefore, by setting the off time to be equal to or longer than the average stay time, the adsorbed molecules can be reliably moved to the crack end. Incidentally, the average staying time of the adsorbed molecules is determined by the desorption energy and the substrate temperature.

In the example shown in FIG. 7, a DC voltage (see FIG. 7A) is applied at the time of off. In this case, the adsorbed molecules are attracted to only one side of the crack. On the other hand, when an AC voltage whose amplitude is lower than the threshold is applied as shown in FIG. 8 within the off time, the electric field alternately reverses, so that the force F acting on the adsorbed molecules also reverses. If the half cycle of the AC voltage is set longer than the average stay time of the adsorbed molecules, the adsorbed molecules are attracted to one side of the crack. Once the adsorbed molecules have moved to the crack end, the electric field strength at the crack end becomes zero, so that even if the electric field direction is reversed, no force is applied and the molecule remains at that position. When the electric field is reversed, a force in the opposite direction is applied to molecules newly adsorbed in the crack, so that the adsorbed molecules are attracted to the opposite side of the crack and fixed. When the AC voltage is applied unlike the DC voltage in this way, it is possible to narrow the crack width symmetrically from both sides of the crack.

The end of the activation process described above can be determined as appropriate while measuring the device current _If and the emission current _Ie .

Step-E: Stabilizing Step The electron-emitting device obtained through such a step is preferably subjected to a stabilizing step. This step 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, it is necessary to keep the partial pressure of this component as low as possible. is there. 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 a partial pressure at which the carbon or carbon compound is not newly deposited. preferable. 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 condition at this time is 80 to 250 ° C., preferably 150 ° C.
As described above, it is desirable that the treatment is performed 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, and is preferably 1.3 × 10 ⁻⁵ Pa or less, more preferably 1.3 × 10 ⁻⁶ Pa or less.

The atmosphere at the time of driving after performing the stabilization step is preferably the same as the atmosphere at the end of the stabilization treatment, but is not limited to this. If the organic substance is sufficiently removed, Even if the pressure itself increases somewhat, it is possible to maintain sufficiently stable characteristics. By adopting such a vacuum atmosphere, the deposition of new carbon or a carbon compound can be suppressed, and as a result, the device current _If and the emission current _Ie can be suppressed.
But it stabilizes.

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

FIG. 9 is a schematic view showing an example of a vacuum processing apparatus. This vacuum processing apparatus also has a function as a measurement and evaluation apparatus. In FIG. 9 as well, the same parts as those shown in FIG. 1 are denoted by the same reference numerals as in FIG.

In FIG. 9, reference numeral 55 denotes a vacuum vessel,
Reference numeral 6 denotes an exhaust pump. An electron-emitting device is provided in the vacuum vessel 55. Reference numeral 51 denotes a power supply for applying a device voltage _Vf to the electron-emitting device; 50, an ammeter for measuring a device current _If flowing through the conductive film 4 between the device electrodes 2 and 3; An anode electrode for capturing the emission current I _e emitted from the electron emission unit 5, a high-voltage power supply 53 for applying a voltage to the anode electrode 54, and a reference numeral 52 for the emission current I _e emitted from the electron emission unit 5. It is an ammeter for measuring. As an example, the measurement can be performed with the voltage of the anode electrode 54 in the range of 1 kV to 10 kV and the distance H between the anode electrode 54 and the electron-emitting device in the range of 2 to 8 mm.

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

The exhaust pump 56 is composed of a normal high vacuum system such as a turbo pump and a rotary pump, and an ultrahigh vacuum system such as an ion pump. The entire vacuum processing apparatus provided with the electron-emitting device substrate shown here 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. 10 is a diagram schematically showing the relationship between the emission current I _e and the device current _If measured using the vacuum processing apparatus shown in FIG. 9, and the device voltage _Vf . In FIG. 10, since the emission current _Ie is significantly smaller than the device current _If , it is shown in arbitrary units. The vertical and horizontal axes are linear scales.

As is clear from FIG. 10, the electron-emitting device of the present invention has the following three characteristic characteristics with respect to the emission current _Ie .

First, when an element voltage higher than a certain voltage (referred to as a threshold voltage; V _{th in} FIG. 10) is applied to the present element, the emission current I _e sharply increases, and on the other hand, the threshold voltage V _th or lower. , The emission current _Ie is hardly detected. That is, it is a non-linear element having a clear threshold voltage V _th with respect to the emission current I _e .

Second, since the emission current _Ie depends monotonically on the device voltage _Vf , the emission current _Ie can be controlled by the device voltage _Vf .

Thirdly, the amount of charge emitted by the anode electrode 54 (see FIG. 9) 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 electron-emitting device of the present invention can easily control the electron-emitting characteristics according to the input signal. By utilizing this property, it is possible to apply to various fields such as an electron source and an image forming apparatus having a plurality of electron-emitting devices.

[0084] In FIG. 10, the element current I _f is monotonously increased with respect to the device voltage V _f (MI characteristic) has shown an example, a voltage-controlled negative resistance with respect to the device current I _f of the element voltage V _f In some cases, resistance characteristics (VCNR characteristics) are shown (not shown). These properties can be controlled by controlling the steps described above.

Next, application examples of the electron-emitting device to which the present invention can be applied will be described below. By arranging a plurality of electron-emitting devices to which the present invention can be applied 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-type 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. 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 electron-emitting device of the present invention has three characteristics as described above. That is, the emission electrons from the surface conduction electron-emitting device can be controlled by the peak value and the width of the pulse-like voltage applied between the opposing device electrodes when the electrons are equal to or higher than the threshold voltage. On the other hand, below the threshold voltage, almost no emission occurs. 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 device,
The electron emission amount can be controlled by selecting the surface conduction electron-emitting device according to the input signal.

Hereinafter, based on this principle, an electron source substrate obtained by arranging a plurality of electron-emitting devices of the present invention will be described with reference to FIG.
This will be described with reference to FIG. In FIG. 11, reference numeral 71 denotes an electron source substrate, 72 denotes an X-direction wiring, and 73 denotes a Y-direction wiring. 74
Is an electron-emitting device, and 75 is a connection.

The m X-direction wirings 72 include D _x1 , D _x2,.
, _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. Y-direction wiring _{73, D y1, D y2, ......} , it consists n wirings of D _yn, 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 using 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 the production 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 device electrodes (not shown) constituting the electron-emitting device 74 are electrically connected to m X-direction wires 72 and n Y-direction wires 73 by a connection 75 made of a conductive metal or the like. It is connected.

The material forming the wiring 72 and the wiring 73, the material forming the connection 75, and the material forming the pair of device electrodes may be the same or different in some or all of the constituent elements. 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.

The X-direction wiring 72 is connected to a scanning signal applying means (not shown) for applying a scanning signal for selecting a row of the electron-emitting devices 74 arranged in the X-direction. On the other hand, a modulation signal generating means (not shown) for modulating each column of the 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.

FIGS. 12 and 13 show an image forming apparatus constructed using such an electron source having a simple matrix arrangement.
This will be described with reference to FIG. FIG. 12 is a schematic diagram illustrating an example of a display panel of the image forming apparatus, and FIG. 13 is a schematic diagram of a fluorescent film used in the image forming apparatus of FIG. FIG. 14 is a block diagram illustrating an example of a drive circuit for performing display according to an NTSC television signal.

In FIG. 12, 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 8 on the inner surface of a glass substrate 83;
4 is a face plate on which a metal back 85 and the like are formed. Reference numeral 82 denotes a support frame, and a rear plate 81 and a face plate 86 are connected to the support frame 82 using frit glass or the like. Reference numeral 88 denotes an envelope, which is sealed by firing at a temperature range of 400 to 500 ° C. for 10 minutes or more in the atmosphere or nitrogen, for example.

Reference numeral 74 denotes an electron-emitting device as shown in FIG. Reference numerals 72 and 73 denote an X-direction wiring and a Y-direction wiring connected to a pair of device electrodes of the surface conduction electron-emitting device.

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 is directly sealed to the substrate 71, and the envelope 8 is formed by the face plate 86, the support frame 82 and the substrate 71.
8 may be configured. On the other hand, by installing a support (not shown) called a spacer between the face plate 86 and the rear plate 81, the envelope 88 having sufficient strength against atmospheric pressure can be configured.

FIG. 13 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, a black conductive material 91 called a black stripe (FIG. 13A) or a black matrix (FIG. 13B) or the like and a fluorescent material 92 may be used depending on the arrangement of the fluorescent materials. it can. 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 the material of the black conductive material 91, 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.

The method of applying the fluorescent substance to the glass substrate 83 can employ a precipitation method or a printing method irrespective 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 a metal back is
The light emitted from the phosphor toward the inner surface is converted into a face plate 8.
Improving the brightness by specular reflection on the 6 side,
The purpose is to function as an electrode for applying an electron beam acceleration voltage, and to protect the phosphor from damage due to collision of negative ions generated in the envelope. The metal back can be manufactured by performing a smoothing process (usually called “filming”) on the inner surface of the fluorescent film after manufacturing the fluorescent film, and then depositing Al using vacuum evaporation or the like.

The face plate 86 is further provided with the fluorescent film 8.
A transparent electrode (not shown) may be provided on the outer surface side of the fluorescent film 84 in order to increase the conductivity of the phosphor film 84.

When performing the above-mentioned sealing, in the case of color, it is necessary to make the phosphors of each color correspond to the electron-emitting devices, and sufficient alignment is indispensable.

The image forming apparatus shown in FIG. 12 is manufactured, for example, as follows.

Through a not-shown exhaust pipe, the interior of the envelope 88 is evacuated to about 1.3 × 10 ⁻⁴ Pa by a usual vacuum system such as a rotary pump or a turbo pump, and Outer terminals _{Dox1 to Doxm} and _{Doy1 to Doyn}
Through the above, a voltage is applied between the device electrodes to perform the above-described forming, and then the activation process is performed by setting the inside of the envelope 88 to a degree of vacuum of about 1.3 × 10 ⁻⁴ Pa by the above-described method of the present invention. By doing so, an electron emission portion is formed to create an electron source substrate. Envelope 88, similar to the aforementioned stabilization step, while being heated appropriately, ion pump, by an exhaust device not using oil, such as a sorption pump evacuated through an exhaust pipe (not shown), 1.3 × 10 ^- After the atmosphere of a vacuum degree of about ⁵ Pa is sufficiently low for the organic substance, sealing is performed. In order to maintain the degree of vacuum after sealing the envelope 88,
Getter processing can also be performed. This is the envelope 88
Immediately before or after sealing, a getter (not shown) disposed at a predetermined position in the envelope 88 is heated by heating using resistance heating, high-frequency heating, or the like to form a vapor deposition film. Processing. The getter is usually composed mainly of Ba or the like.
The vacuum degree of 10 ^{−3 to} 1.3 × 10 ⁻⁵ Pa is maintained.

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.
101 is an image display panel, 102 is a scanning circuit, 103 is a control circuit, 104 is a shift register, 105 is a line memory, 106 is a synchronization signal separation circuit, 107 is a modulation signal generator, and Vx and Va are DC voltage sources.

The display panel 101 has terminals D _ox1 through D _ox1
oxm , terminals _{Doy1 to Doyn} and a high voltage terminal 87 are connected to an external electric circuit. Terminals D _{ox1 to} D _oxm
Is applied with a scanning signal for sequentially driving electron sources provided in the display panel 101, that is, electron emission element groups arranged in a matrix of m rows and n columns, one row at a time (n elements). Is done. The terminal D _Oy1 to _D oyn, modulation signals for controlling the output electron beam of each of the electron-emitting devices of one row selected by a scan signal. The high-voltage terminal 87 is supplied with a DC voltage of, for example, 10 kV from a DC voltage source Va. This is for applying sufficient energy to the electron beam emitted from the electron-emitting device to excite the phosphor. Is the accelerating voltage.

The scanning circuit 102 will be described. The circuit includes m switching elements (S _{1 to} S
_m is schematically shown). Each switching element selects either the output voltage of the DC voltage power supply Vx or 0 [V] (ground level),
To terminal D _ox1 of the display panel 101 is connected to D _oxm and electrically. Each switching element S ₁ to S _m, the control circuit 103 operates based on a control signal T _scan that outputs can be configured by combining switching elements such as FET.

In the case of this example, the DC voltage source Vx is such that the drive voltage applied to the unscanned element is equal to or lower than the electron emission threshold voltage based on the characteristics (electron emission threshold voltage) of the electron emission element. It is set to output a constant 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 in accordance with the synchronization signal T _sync sent from the synchronous signal separation circuit 106, T _scan, generating a respective control signal T _sft and T _mry to each unit.

The synchronizing signal separating circuit 106 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 106 includes a vertical synchronizing signal and a horizontal synchronizing signal, but is illustrated here as a _Tsync signal for convenience of explanation. The luminance signal component of the image separated from the television signal is represented as a DATA signal for convenience. This DATA signal is input to the shift register 104.

The shift register 104 is for serially / parallel-converting the DATA signal input serially in time series for each line of an image, and converts the DATA signal into a control signal _Tsft sent from the control circuit 103. (Ie, the control signal T _sft is applied to the shift register 10
4 may be rephrased as the shift clock. ). The data for one line of the serial / parallel-converted image (corresponding to the drive data for n electron-emitting devices) is I _d1
To _{Idn as} the n parallel signals.
04.

[0112] The line memory 105 is a storage device for storing only of data for one line, stores the contents of appropriate I _d1 to I _dn according to the control signal T _mry sent from the control circuit 103 I do. The stored contents are output as I _{d′ 1 to} I _{d′ n} and input to the modulation signal generator 107.

Modulation signal generator 107 outputs image data I
_d'1 to according to each of the I _d'n, a signal source for appropriately driving modulating each of the electron-emitting device, the output signal, the electronic display panel 101 through the terminals D _Oy1 to D _Oyn Applied to the emitting element.

As described above, the electron-emitting device of the present invention 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. From this, when a pulse-like voltage is applied to this element, for example, when a voltage lower than the electron emission threshold voltage is applied, electron emission does not occur, but when a voltage higher than the electron emission threshold voltage is applied, electrons are not emitted. A beam is output. At that time, the intensity of the output electron beam can be controlled by changing the peak value Vm of the pulse. Further, by changing the pulse width Pw, it is possible to control the total amount of charges of the output electron beam.

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 adopted. When implementing the voltage modulation method, the modulation signal generator 107 generates a voltage pulse of a fixed length, and a voltage modulation circuit capable of appropriately modulating the peak value of the voltage pulse according to input data. Can be used. When implementing the pulse width modulation method, the modulation signal generator 107 generates a voltage pulse having a constant peak value and modulates the width of the voltage pulse appropriately according to input data. A circuit can be used.

The shift register 104 and the line memory 10
5 can be 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 synchronization signal separation circuit 106 into a digital signal. For this purpose, an A / D converter is provided at the output of the synchronization signal separation circuit 106. Just do it. In this connection, the circuit used for the modulation signal generator 107 is slightly different depending on whether the output signal of the line memory 105 is a digital signal or an analog signal. That is, in the case of the voltage modulation method using a digital signal, the modulation signal generator 107 includes:
For example, a D / 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 107 includes, for example, a high-speed oscillator, a counter that counts the number of waves output from the oscillator, and a comparator that compares the output value of the counter with the output value of the memory. (Comparator) is used. If necessary, an amplifier for amplifying the pulse width modulated signal output from the comparator to the drive voltage of the 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 or the like can be used as the modulation signal generator 107, 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 oscillator (VCO) can be employed, and an amplifier for amplifying the voltage up to the driving voltage of the electron-emitting device can be added as necessary.

In the image forming apparatus of the present invention which can have such a configuration, each of the electron-emitting devices is provided with an external container terminal D.
_ox1 to D _oxm, by applying a voltage via the D _Oy1 to _D oyn, electron emission occurs. A high voltage is applied to the metal back 85 or a transparent electrode (not shown) via the high voltage terminal 87 to accelerate the electron beam. The accelerated electrons collide with the fluorescent film 84 and emit light to form an image.

The configuration of the image forming apparatus described here is an example of the image forming apparatus of the present invention, and various modifications can be made based on the technical idea of the present invention. N for input signal
Although the TSC system has been described, the input signal is not limited to this, and a PAL, SECAM system, or other TV signal including a larger number of scanning lines (eg, a high-quality TV including the MUSE system). A method can also be adopted.

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

FIG. 15 is a schematic view showing an example of a ladder type electron source. In FIG. 15, reference numeral 110 denotes an electron source substrate, and 111 denotes an electron-emitting device. Reference numeral 112 denotes common wirings D _{x1 to} D _x10 for connecting the electron-emitting devices 111, and these are drawn out as external terminals. A plurality of electron-emitting devices 111 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 the element rows where the electron beam is to be emitted, and a voltage equal to or lower than the electron emission threshold is applied to the element rows where the electron beam is not desired to be emitted. The common wirings D _{x2 to} D _x9 located between the element rows are, for example, D _x2 and D _x3 , D _x4 and D _x5 ,
D _x6 and D _x7 , and D _x8 and D _x9 , can also be formed as one and the same wiring.

FIG. 16 is a schematic diagram showing an example of a panel structure in an image forming apparatus having a ladder-type electron source. 120 is a grid electrode, 121 is an opening through which electrons pass, D _{ox1 to} D _oxm are terminals outside the container, and G _{1 to} G
_n is an external terminal connected to the grid electrode 120. Reference numeral 110 denotes an electron source substrate in which the common wiring between each element row is the same wiring. In FIG. 16, the same portions as those shown in FIGS. 12 and 15 are denoted by the same reference numerals as those shown in these drawings. An image forming apparatus shown here;
The major difference from the image forming apparatus having the simple matrix arrangement shown in FIG.
6 whether or not the grid electrode 120 is provided.

In FIG. 16, 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 electron-emitting device 111,
In order to allow an electron beam to pass through stripe-shaped electrodes provided orthogonally to the ladder-type element rows, one circular opening 121 is provided for each element. The shape and arrangement position of the grid electrode are not limited to those shown in FIG. For example, a large number of passage openings can be provided in a mesh shape as openings, and a grid electrode can be provided around or near the electron-emitting device.

The external terminals D _{ox1 to} D _oxm and the external terminals G _{1 to} G _n 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 described above is a display apparatus for a television broadcast, a display apparatus such as a video conference system and a computer, and an image forming apparatus as an optical printer using a photosensitive drum or the like. Etc. can also be used.

[0128]

EXAMPLES The present invention will be described below with reference to specific examples. However, the present invention is not limited to these examples, and the present invention is not limited to these examples. This includes the case where the element is replaced or the design is changed.

[Embodiment 1] The basic structure of an electron-emitting device according to this embodiment is the same as that of FIG. The method for manufacturing the electron-emitting device in this embodiment is basically the same as that shown in FIG. Hereinafter, a method for manufacturing the electron-emitting device according to the present embodiment will be described with reference to FIGS.

Step- (1) A silicon oxide film having a thickness of 0.5 μm is formed on a cleaned blue plate glass by a sputtering method and used as a substrate 1. On such a substrate 1, a photoresist (RD-2000N-41 / 1) having an opening corresponding to the element electrode pattern is provided.
A mask pattern (manufactured by Hitachi Chemical Co., Ltd.) was formed, and 5 nm thick Ti and 100 nm thick Ni were sequentially deposited by a vacuum evaporation method. Next, dissolve the photoresist with an organic solvent,
The Ni / Ti film was lifted off to form device electrodes 2 and 3 (FIG. 3A). The distance L between the device electrodes is 10 μm, and the width W of the device electrode is 300 μm.

Step- (2) A Cr film having a thickness of 100 nm is formed on the above-mentioned element by a vacuum evaporation method, an opening corresponding to the pattern of the conductive film is provided by photolithography, and a Cr film for forming the conductive film is formed. A mask was formed. This is mixed with a Pd amine complex solution (c
cp4230 / Okuno Pharmaceutical Co., Ltd.) using a spinner, baking at 300 ° C. for 10 minutes in air, and
A conductive film containing dO as a main component was formed. The thickness of this film was 10 nm. The Cr mask was removed by wet etching, and unnecessary portions of the PdO fine particle film were lifted off to obtain a conductive film 4 having a desired shape (FIG. 3).
(B)). The resistance value of the conductive film is Rs = 2 × 10 ⁴ Ω
/ □.

Step- (3) The substrate on which the device electrodes 2 and 3 and the conductive film 4 are formed is set in the vacuum vessel 55 of the apparatus shown in FIG. Is 1.3 × 10 ⁻³ P
a. The exhaust device used at this time is a so-called high vacuum exhaust device including a turbo pump and a rotary pump. The exhaust device 56 is further provided with an ion pump for ultra-high vacuum, and can be appropriately switched and used.
A pulse voltage was applied from a power supply 51 for applying an element voltage _Vf to the element, and a forming process was performed to form an electron-emitting portion 5 (FIG. 3C). The waveform of the pulse voltage at this time is a triangular-wave pulse whose peak value gradually increases as shown in FIG. 4B, and the pulse width T ₁ is 1 msec. , The pulse interval T ₂ is 10 msec. And Also, during the forming process, a resistance measuring pulse of 0.1 V was inserted within the pause time of the forming pulse, and the forming process was terminated when the resistance value exceeded 1 MΩ.

The crest value of the pulse at the end of the forming is
It was 5.0-5.1V. At this time, the pressure inside the vacuum vessel was 2.7 × 10 ⁻³ Pa.

Step- (4) Next, when a pulse voltage was applied from the power supply 51 for applying the device voltage _Vf to the device and the activation process was performed, it was almost 0 before the activation process. The device current _If and the emission current _Ie are remarkably changed and increased.

The voltage waveform of the activation process used in this embodiment is the same as that of FIG. 5, and in this embodiment, the pulse interval T _{2 is set} to 10
msec. , And a pulse width of T ₁₀ = 1 μsec. From T _1n = 5 msec. It was gradually increased in steps. When the peak value (peak voltage at the time of activation) of the rectangular wave was set to 16 V, the time required for the activation process was 40 minutes.

Step- (5) In order to grasp the characteristics of the electron-emitting device manufactured in the above-described steps, the electron-emitting characteristics were measured using the vacuum processing apparatus shown in FIG.

The electron emission characteristics were measured by setting the distance H between the anode electrode 54 and the electron-emitting device to 5 mm, setting the potential of the anode electrode 54 to 1 kV, and setting the degree of vacuum in the vacuum device to 1.3 when measuring the electron emission characteristics. × 10 ^-4 Pa.

As a result, a current-voltage characteristic as shown in FIG. 10 was obtained. In this element, the element voltage is 10 V
The emission current _Ie suddenly increases from about
In this case, the device current _If is 1.5 mA, the emission current _Ie is 1.
5 μA, and the electron emission efficiency η = I _e / _If (%) was 0.1%.

[Comparative Example 1] In this comparative example, the voltage waveform of the activation process was set to a pulse width of 0.5 msec. And the pulse interval is 10 msec. An electron-emitting device was prepared in the same manner as in Example 1, except that the electron emission element was fixed. As a result, the activation processing time required to obtain the same device current as in the first embodiment is 6 hours.
It was 0 minutes. FIG. 17A shows the profiles of Example 1 and this comparative example during activation.

The electron emission characteristics of the device of this comparative example fabricated as described above were measured in the same manner as in Example 1. As a result, the emission current _Ie rapidly increased from the device voltage of about 10 V, and the device voltage of 15 V Then, the element current _If is 1.5 m
A, the emission current _Ie was 0.62 μA, and the electron emission efficiency η = _Ie / _If (%) was 0.04%.

When the surface conduction electron-emitting devices prepared in Example 1 and Comparative Example 1 were observed with a scanning electron microscope, both of them revealed that the conductive film had cracks almost at the center between the device electrodes. Carbon and carbon compounds were deposited in the crack. However, the crack width of the device of Example 1 was smaller than the device of Comparative Example 1. This is because in Comparative Example 1, since a voltage having a long pulse width was applied from the initial stage of activation, a phenomenon that the crack width became large occurred, and it was difficult for carbon and carbon compounds to sufficiently deposit in such a portion in a short time. it is conceivable that.
On the other hand, in Example 1 according to the present invention, the pulse width in the early stage of activation was sufficiently shortened, so that the spread of the crack width due to a temperature rise near the crack was suppressed, and carbon and carbon compounds were deposited in the crack in the early stage of activation. It is thought that it was possible. In addition, it is considered that when a carbon and / or carbon compound deposited film is formed to some extent, the deposited film has a function of protecting the conductive film and has an effect of suppressing the spread of the crack width.

As described above, the same device current was obtained in both Example 1 and Comparative Example 1. However, comparing the device characteristics of the devices finally manufactured, the effectiveness of the present invention is shown. It can be said that.

[Embodiment 2] In this embodiment, step- (3)
After the device was fabricated in the same manner as in Example 1, the inside of the vacuum vessel 55 of the device shown in FIG. 9 where the device was installed was sufficiently evacuated with an ion pump, and then about 2.7 × 10 ^-1 Pa was obtained. Acetone was introduced, a pulse voltage was applied from a power supply 51 for applying a device voltage _Vf to the device, and an activation process was performed. As a result, the device current _If and the device current _If , which were almost 0 before the activation process, were increased. The emission current _Ie changed significantly and increased.

The voltage waveform, pulse width, and pulse interval of the activation process used in this embodiment are the same as those in the first embodiment. When the peak value of the rectangular wave (peak voltage at the time of activation) is set to 16 V, the activation is performed. The time required for the chemical conversion treatment was 40 minutes.

The electron emission characteristics of the device manufactured as described above were measured in the same manner as in Example 1. As a result, the current-voltage characteristics as shown in FIG. 10 were obtained. In this device, the emission current I suddenly increases from a device voltage of about 10V.
_e increases, and at a device voltage of 15 V, the device current _If becomes 2..
The emission current _Ie was 2.9 μA, and the electron emission efficiency η = _Ie / _If (%) was 0.15%.

[Comparative Example 2] In this comparative example, the voltage waveform of the activation process is set to a pulse width of 0.5 msec. And the pulse interval is 10 msec. An electron-emitting device was produced in the same manner as in Example 2, except that the electron emission element was fixed. The time required for the activation process is
As in Example 2, it took 40 minutes.

The electron emission characteristics of the device of this comparative example fabricated as described above were measured in the same manner as in Example 1. As a result, the emission current _Ie rapidly increased from the device voltage of about 10 V, and the device voltage was increased to 15 V. Then, the element current _If is 2.0 m
A, the emission current I _e becomes 2.1 μA, and the electron emission efficiency η
= _Ie / _If (%) was 0.11%.

In both Example 2 and Comparative Example 2, the device current amount was saturated in about the same time. However, comparing the device characteristics of the devices finally manufactured, it can be said that the effectiveness of the present invention is shown. .

[Embodiment 3] In this embodiment, step- (3)
After the device was fabricated in the same manner as in Example 1, the interior of the vacuum vessel 55 of the device shown in FIG. 9 where the device was installed was sufficiently evacuated with an ion pump, and then about 1.3 × 10 ⁻¹ Pa was obtained. Acetone was introduced, a pulse voltage was applied from a power supply 51 for applying a device voltage _Vf to the device, and an activation process was performed. As a result, the device current _If and the device current _If , which were almost 0 before the activation process, were increased. The emission current _Ie changed significantly and increased.

FIG. 18 shows the voltage waveform of the activation process used in this embodiment. In this embodiment, the peak value is 16 V, the pulse width is 1 msec. A bipolar pulse voltage having a frequency of 50 Hz and a bipolar polarity was applied for 40 minutes to activate. Here, a DC voltage of 8 V was applied during the time between pulses (9 msec.).

The electron emission characteristics of the device fabricated as described above were measured in the same manner as in Example 1. As a result, current-voltage characteristics as shown in FIG. 10 were obtained. In this device, the emission current I suddenly increases from a device voltage of about 10V.
_e increases, and at a device voltage of 15 V, the device current _If becomes 2..
2 mA, the emission current _Ie was 3.0 μA, and the electron emission efficiency η = _Ie / _If (%) was 0.14%.

[Embodiment 4] In this embodiment, an electron-emitting device was prepared in the same manner as in Embodiment 3, except that the voltage waveform shown in FIG. 19 was used for the activation process. The time required for the activation process is 40 minutes, as in the third embodiment.

The electron emission characteristics of the device fabricated as described above were measured in the same manner as in Example 1. As a result, current-voltage characteristics as shown in FIG. 10 were obtained. In this device, the emission current I suddenly increases from a device voltage of about 10V.
_e increases, and at a device voltage of 15 V, the device current _If becomes 2..
4 mA, the emission current _Ie was 3.1 μA, and the electron emission efficiency η = _Ie / _If (%) was 0.13%.

When the device characteristics of the devices finally manufactured in Examples 3 and 4 and Comparative Example 2 are compared, it can be said that the effectiveness of the present invention is shown.

[Embodiment 5] In this embodiment, an image forming apparatus is manufactured using an electron source (see FIG. 11) in which a large number of electron-emitting devices are arranged in a simple matrix.

FIG. 20 is a plan view of a part of a substrate on which a plurality of conductive films are arranged in a matrix. Also, A- in FIG.
FIG. 21 is a sectional view taken along the line A ′. However, the components denoted by the same reference numerals in FIGS. 20 and 21 indicate the same members. Here, 71 is a substrate, 2 and 3 are device electrodes, and 4 is a conductive film. _Reference numeral 72 denotes an X-direction wiring (also referred to as a lower wiring) corresponding to _Dxm in FIG. 11, 73 denotes a Y-direction wiring (also referred to as an upper wiring) corresponding to _Dyn in FIG. 11, 151 denotes an interlayer insulating layer, and 152 denotes an element electrode. This is a contact hole for electrical connection between the second wiring 2 and the lower wiring 72.

First, a method of manufacturing an electron source substrate according to this embodiment will be described in the order of steps with reference to FIGS. still,
Steps -a to g described below correspond to (a) to (d) of FIG. 22 and (e) to (g) of FIG. 23, respectively.

Step-a A 5 nm-thick Cr film and a 600 nm-thick Au film were formed by vacuum evaporation on a substrate 71 having a 0.5 μm-thick silicon oxide film formed on a cleaned blue plate glass by a sputtering method. After sequentially laminating, a photoresist (AZ1370 / Hoechst) is spin-coated with a spinner and baked, then a photomask image is exposed and developed to form a resist pattern of the lower wiring 72, and the Au / Cr deposited film is wet-etched. Thus, a lower wiring 72 having a desired shape was formed.

Step-b Next, an interlayer insulating layer 151 made of a silicon oxide film having a thickness of 1.0 μm was deposited by RF sputtering.

Step-c Contact hole 1 was formed in the silicon oxide film deposited in step b.
A photoresist pattern for forming 52 was formed, and using this as a mask, the interlayer insulating layer 151 was etched to form a contact hole 152. Etching is CF ₄
And using the H ₂ gas RIE (Reactive Ion
Etching) method.

Step-d Thereafter, a pattern to be a gap L between the device electrodes 2 and 3 and the device electrode is formed by a photoresist (RD-2000N-41).
/ Hitachi Chemical Co., Ltd.) and a thickness of 5
nm of Ti and 100 nm of Ni were sequentially deposited. The photoresist pattern is dissolved in an organic solvent, and Ni / T
The i-deposited film is lifted off, and the element electrode interval L is 10 μm,
Device electrodes 2 and 3 having a device electrode length W of 300 μm were formed.

Step-e After a photoresist pattern of the upper wiring 73 was formed on the device electrodes 2 and 3, Ti having a thickness of 5 nm and Au having a thickness of 500 nm were sequentially deposited by vacuum evaporation. The photoresist pattern was dissolved with an organic solvent, the Au / Ti deposited film was lifted off, and an upper wiring 73 having a desired shape was formed.

Step-f Next, a Cr film having a thickness of 100 nm is formed by a vacuum evaporation method, an opening corresponding to the pattern of the conductive film is provided by photolithography, and a Cr film for forming the conductive film is formed.
A mask was formed. Add Pd amine complex solution (ccp
4230 / Okuno Pharmaceutical Co., Ltd.) using a spinner, baking at 300 ° C. for 10 minutes in the air, and performing PdO
Was formed as the main component. The thickness of this film is 1
It was 0 nm. The Cr mask was removed by wet etching, and unnecessary portions of the PdO fine particle film were lifted off to obtain a conductive film 4 having a desired shape. The resistance value of the conductive film was Rs = 2 × 10 ⁴ Ω / □.

Step-g A resist pattern having an opening at the contact hole 152 was formed, and 5 nm thick Ti and 500 nm thick Au were sequentially deposited by vacuum evaporation. Unnecessary portions are removed by lift-off, so that contact holes 1
52 was embedded.

Through the above steps, the lower wiring 72, the interlayer insulating layer 151, the upper wiring 73, the device electrodes 2, 3, and the conductive film 4 were formed on the insulating substrate 71.

Next, an image forming apparatus was manufactured using the substrate 71 (FIG. 20) on which the plurality of conductive films 4 manufactured as described above were arranged in a matrix. The manufacturing procedure will be described with reference to FIGS.

First, a substrate 71 (FIG. 20) on which the plurality of conductive films 4 are arranged in a matrix is fixed on a rear plate 81, and a face plate 86 (on the inner surface of the glass substrate 83) is placed 5 mm above the substrate 71. A fluorescent film 84 and a metal back 85 are formed via a support frame 82, and frit glass is applied to the joint between the face plate 86, the support frame 82, and the rear plate 81. The panel was sealed by firing at 15 ° C. for 15 minutes to form a panel (envelope 88 in FIG. 12). The fixing of the substrate 71 to the rear plate 81 was also performed with frit glass.

The fluorescent film 84 is used to realize color.
A phosphor in the form of a stripe (see FIG. 13A) was formed, a black stripe was formed first, and phosphors 92 of each color were applied to the gaps by a slurry method to form a phosphor film 84. As a material of the black stripe, a material mainly containing graphite, which is generally used, was used.

Further, a metal back 85 was provided on the inner surface side of the fluorescent film 84. The metal back 85 is manufactured by performing a smoothing process (usually called filming) on the inner surface of the fluorescent film 84 after the fluorescent film 84 is manufactured, and then performing vacuum deposition of Al.

The face plate 86 is further provided with a fluorescent film 8.
In some cases, a transparent electrode is provided on the outer surface side of the fluorescent film 84 in order to increase the conductivity of the metal back 8.
5 was omitted because sufficient conductivity was obtained.

The atmosphere in the envelope 88 completed as described above is evacuated by a vacuum pump through an exhaust pipe (not shown), and after reaching a sufficient degree of vacuum, the outer terminals D _{ox1 to} D _{ox1 to} D
The pulse voltage was applied between the device electrodes 2 and 3 of _oxm and D _Oy1 to the electron-emitting device 74 through the _D oyn, it was forming process. In the present embodiment, a pulse as shown in FIG. 4B is used, and the pulse width T _{1 is set} to 1 msec. , The pulse interval T ₂ is 10 msec. And the peak value is from 0 V to 0.1 V
The temperature was gradually raised in steps and performed in a vacuum atmosphere of about 1.3 × 10 ⁻³ Pa.

Next, the external terminals D _{ox1 to} D _oxm and D _oxm
oy1 to the device electrodes 2 of the electron-emitting device 74 through the _D oyn,
An activation process was performed by applying a pulse voltage between the three. In this embodiment, the peak value of the rectangular wave (peak voltage at the time of activation) is set to 16 V, and activation is performed in the same manner as in the first embodiment.

Thereafter, the exhaust pipe (not shown) was welded by heating with a gas burner at a degree of vacuum of about 1.3 × 10 ⁻³ Pa, and the envelope 88 was sealed. Finally, gettering was performed by a high-frequency heating method to maintain the degree of vacuum after sealing.

The external terminals _{Dox1 to Doxm} and _{Doy1 to Doyn} and the high voltage terminal 87 of the display panel manufactured as described above were connected to necessary driving systems, respectively, to complete an image forming apparatus. A scanning signal and a modulation signal are applied to the respective electron-emitting devices from signal generating means (not shown ₎ through external terminals _{Dox1 to Doxm} and _{Doy1 to Doyn} , respectively, thereby emitting electrons. 8
5 was applied with a high voltage of several kV or more to accelerate the electron beam, collide with the fluorescent film 84, and excite and emit light to display an image.

As a result, in the image forming apparatus of this embodiment,
Bright, high-quality images could be displayed with low current.

[0176]

According to the first method for manufacturing an electron-emitting device of the present invention, by reducing the applied pulse width in the early stage of activation as much as possible, a stable carbon is formed inside the crack of the conductive film in the early stage of activation. And / or immobilize carbon compounds. For this reason, the regression of the crack (expansion of the crack width) as seen in the early stage of the conventional activation process can be minimized, and the generation of a region that does not control electron emission (inactive region) is minimized. Accordingly, electrons can be emitted from the entire region corresponding to the element width, and the electron emission efficiency can be increased. Further, since there is no leak region, stable electron emission characteristics can be obtained.

According to the second method for manufacturing an electron-emitting device of the present invention, the DC or AC voltage having a voltage lower than the threshold of the device voltage with respect to the device current is set within the non-application time of the pulse voltage in the activation step. By applying a voltage, a crack in the conductive film can be stably narrowed, and an electron-emitting device having high electron-emitting efficiency can be provided.

Further, in an electron source having a large number of electron-emitting devices arranged, the electron-emitting characteristics of each electron-emitting device can be made uniform, and an image forming apparatus with high uniformity can be provided. An image forming apparatus capable of forming an image with excellent operation stability can be provided. For example, in an image forming apparatus using a phosphor as an image forming member, a bright, high-quality image forming apparatus with low current, such as a color flat television, is realized.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of an electron-emitting device to which the present invention can be applied.

FIG. 2 is a schematic diagram showing another example of an electron-emitting device to which the present invention can be applied.

FIG. 3 is a view illustrating a method for manufacturing an electron-emitting device according to the present invention.

FIG. 4 is a schematic diagram showing an example of a voltage waveform in a current forming process that can be employed in manufacturing the electron-emitting device of the present invention.

FIG. 5 is a schematic diagram showing an example of a voltage waveform in an activation process of the first manufacturing method of the present invention.

FIG. 6 is a schematic diagram for explaining a phenomenon in the activation process.

FIG. 7 is a schematic diagram showing an example of a voltage waveform and a phenomenon in an activation process of the second manufacturing method of the present invention.

FIG. 8 is a schematic diagram showing another example of the voltage waveform in the activation process of the second manufacturing method of the present invention.

FIG. 9 is a schematic configuration diagram showing an example of a vacuum processing apparatus (measurement evaluation apparatus) that can be used for manufacturing the electron-emitting device of the present invention.

FIG. 10 is a diagram showing electron emission characteristics of the electron-emitting device of the present invention.

FIG. 11 is a schematic view showing an example of an electron source having a simple matrix arrangement according to the present invention.

FIG. 12 is a schematic diagram illustrating an example of a display panel of the image forming apparatus of the present invention.

FIG. 13 is a schematic diagram illustrating an example of a fluorescent film in a display panel.

FIG. 14 is a block diagram illustrating an example of a drive circuit for performing display in accordance with an NTSC television signal in the image forming apparatus of the present invention.

FIG. 15 is a schematic diagram illustrating an example of an electron source having a ladder-type arrangement according to the present invention.

FIG. 16 is a schematic diagram illustrating an example of a display panel of the image forming apparatus of the present invention.

FIG. 17 is a schematic diagram showing a change over time of an element current amount during activation in Example 1 and Comparative Example 1.

FIG. 18 is a schematic diagram illustrating a voltage waveform of an activation process according to the third embodiment.

FIG. 19 is a schematic diagram illustrating a voltage waveform of an activation process according to the fourth embodiment.

FIG. 20 is a schematic diagram showing a part of a matrix-wired electron source according to a fifth embodiment.

21 is a schematic sectional view taken along line A-A 'of FIG.

FIG. 22 is a diagram illustrating a manufacturing process of the electron source in FIG. 20;

FIG. 23 is a diagram illustrating a manufacturing process of the electron source in FIG. 20;

FIG. 24 is a schematic view showing an example of a surface conduction electron-emitting device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Substrate 2, 3 Element electrode 4 Conductive film 5 Electron emission part 50 Ammeter for measuring element current _If 51 Power supply for applying element voltage _Vf to electron emission element 52 Emitted from electron emission part 5 Ammeter 53 for measuring the emission current _Ie which is supplied 53 A high voltage power supply for applying a voltage to the anode electrode 54 54 An anode electrode for capturing electrons emitted from the electron emission section 5 55 Vacuum container 56 Exhaust pump 71 Electrons Source substrate 72 X-direction wiring 73 Y-direction wiring 74 Electron emission device 75 Connection 81 Rear plate 82 Support frame 83 Glass substrate 84 Phosphor film 85 Metal back 86 Face plate 87 High voltage terminal 88 Envelope 91 Black conductive material 92 Phosphor 101 Display Panel 102 scanning circuit 103 control circuit 104 shift register 105 line memory 106 synchronization signal Releasing circuit 107 a modulation signal generator Vx, Va dc voltage source 110 the electron source substrate 111 electron emitters 112 electron emitters opening 151 interlayer insulating layer 152 a contact hole for the common wiring 120 grid electrodes 121 electrons pass through for wiring

Claims (15)

[Claims] 1. A method of manufacturing an electron-emitting device having a conductive film including an electron-emitting portion between a pair of electrodes on a substrate, comprising: a forming step of forming an electron-emitting portion in the conductive film; An activation step of repeatedly applying a pulse voltage between the electrodes under an atmosphere, wherein the length of the application time of the pulse voltage in the activation step is:
A method for manufacturing an electron-emitting device, wherein the length of the non-application time is varied. 2. The method according to claim 1, wherein the length of the application time of the pulse voltage in the activation step is gradually increased in a stepwise manner with respect to the length of the non-application time. Method. 3. The method according to claim 1, wherein the peak value of the pulse voltage in the activation step is gradually increased stepwise.
Or the method for manufacturing an electron-emitting device according to 2. 4. A method of manufacturing an electron-emitting device having a conductive film including an electron-emitting portion between a pair of electrodes on a substrate, comprising: a forming step of forming an electron-emitting portion in the conductive film; An activation step of repeatedly applying a pulse voltage between the electrodes under an atmosphere, and applying a voltage lower than a threshold of an element voltage to an element current within a non-application time of the pulse voltage in the activation step. A method for manufacturing an electron-emitting device. 5. The manufacturing of the electron-emitting device according to claim 4, wherein a DC voltage lower than a threshold value of the device voltage with respect to the device current is applied within a non-application time of the pulse voltage in the activation step. Method. 6. The method according to claim 5, wherein the non-application time of the pulse voltage in the activation step is longer than the average residence time of the gas molecules of the organic substance on the substrate surface. Method. 7. The electron-emitting device according to claim 4, wherein an AC voltage whose amplitude is lower than a threshold value of the device voltage with respect to the device current is applied within a non-application time of the pulse voltage in the activation step. Manufacturing method. 8. The method according to claim 7, wherein a half cycle of the AC voltage is longer than an average residence time of gas molecules of the organic substance on a substrate surface. 9. An electron-emitting device manufactured by the method according to claim 1. Description: 10. A method for manufacturing an electron source in which a plurality of electron-emitting devices having a conductive film including a pair of electrodes and an electron-emitting portion are disposed on a substrate, wherein the plurality of electron-emitting devices are A method for manufacturing an electron source, wherein the method is performed by the method according to any one of claims 9 to 13. 11. An electron source manufactured by the method according to claim 10. 12. The electron source according to claim 11, wherein the plurality of electron-emitting devices are wired in a matrix. 13. The electron source according to claim 11, wherein the plurality of electron-emitting devices are wired in a ladder shape. 14. An electron source in which a plurality of electron-emitting devices having a pair of electrodes and a conductive film including an electron-emitting portion are arranged on a base, and an image is formed by irradiation of an electron beam emitted from the electron source. A method for manufacturing an image forming apparatus having an image forming member, wherein the electron source is manufactured by the method according to claim 10. 15. An image forming apparatus manufactured by the method according to claim 14.