JP2000251620A - Electron emitting element, electron source, image forming apparatus using the same, and methods of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a good electron emission while suppressing dissolution and aggregation of a conductive thin film and obtaining a large emission current in an electron-emitting device, stabilizing the surface potential of an insulating surface in the vicinity of an electron-emitting portion, and providing excellent electron emission. Maintain characteristics for a long time. SOLUTION: A pair of opposing element electrodes formed on a base, a conductive thin film formed in electrical communication with the element electrodes, an electron emitting portion formed on a part of the conductive thin film,
Wherein at least a part of the conductive thin film is covered with a nitride.

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.

[0002]

2. Description of the Related Art Conventionally, two types of electron-emitting devices using a thermionic electron-emitting device and a cold-cathode electron-emitting device have been known. The cold cathode electron emitting device includes a field emission type (hereinafter, referred to as “FE type”), a metal / insulating layer / metal type (hereinafter, referred to as “MIM type”), a surface conduction type electron emitting device, and the like. As an example of the FE type, [W. P. Dyke &
W. W. Dolan: "Field emissio
n ", Advance in Electron Phy
sics, 8, 89 (1956)] or [C. A. S
pindt: "PHYSICAL Property
s of thin-film field emis
sion cathodes with mollybd
eneium cones ", J. Appl. Phys.
s. , 47, 5248 (1976)].

As an example of the MIM type, [C. A. Mea
d: “Operation of Tunnel-Em
issue Devices ", J. Apply. P.
hys. , 32, 646 (1961)].

As an example of the surface conduction electron-emitting device,
[M. I. Elinson: RecioEng. Ele
ctron Phys. , 10, 1290, (196
5)].

[0005] The surface conduction electron-emitting device utilizes a phenomenon in which an electron is emitted by passing a current 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 / S
nO ₂ thin film [M. Hartwell and
C. G. FIG. Fonstad: "IEEE Trans.
Ed Conf. "519 (1975)], using a carbon thin film [Hisashi Araki et al .: Vacuum, Vol. 26, No. 1,
22 (1983)].

A typical example of a surface conduction electron-emitting device is a conductive film made of metal, nitride, or the like provided between a pair of device electrodes provided on a substrate.
An example in which an electron emission portion is formed by an energization process called energization forming in advance. That is, the energization forming means applying a direct current voltage or a very slowly increasing voltage, for example, about 1 V / min, to both sides of the conductive film and energizing the conductive film to locally destroy, deform or alter the conductive film, This is a process for forming an electron emission portion in a high resistance state. In the electron emitting portion, a crack is generated in a part of the conductive film, and electrons are emitted from the vicinity of the crack.

The above-mentioned surface conduction electron-emitting device has an advantage that it can be formed in a large number over a large area since it has a simple structure and is easy to manufacture. Therefore, various applications for making use of this feature are being studied. For example, application to an image forming apparatus such as a display device is given.

Conventionally, as an example in which a large number of surface conduction electron-emitting devices are arranged, a surface conduction electron-emitting device is arranged in parallel, and both ends (both device electrodes) of the surface conduction electron-emitting device are wired. An electron source in which a large number of rows (also referred to as common wiring) are arranged (also referred to as a ladder-type arrangement) in a large number of rows (also referred to as a ladder-type arrangement) is disclosed.
JP-A-213749 and JP-A-2-257552).
In particular, in the case of a display device, a flat panel display device similar to a display device using liquid crystal can be used, and a large number of surface conduction electron-emitting devices are used as self-luminous display devices that do not require a backlight. A display device has been proposed in which an arranged electron source is combined with a phosphor that emits visible light when irradiated with an electron beam from the electron source (US Pat. No. 506).
No. 6883).

[0009]

As for the electron-emitting device applied to the above-mentioned electron source and image forming apparatus, in order to stably provide a bright display image, more stable electron emission characteristics and improvement of electron emission efficiency are achieved. Is required. Here, the efficiency is such that when a voltage is applied to a pair of device electrodes of a surface conduction electron-emitting device, a current flowing between the two electrodes (hereinafter, referred to as a “device current If”) and a current discharged into a vacuum ( (Hereinafter referred to as “emission current Ie”), and it is desirable that the device current If be small and the emission current Ie be large. If the electron emission characteristics that can be controlled stably and the efficiency are improved, for example, in an image forming apparatus using a phosphor as an image forming member, a low-current, bright, high-quality image forming apparatus such as a flat television can be realized. . Further, as the current is reduced, the cost of a driving circuit and the like constituting the image forming apparatus can be reduced.

However, in the above-mentioned conventional electron-emitting device, the stability of the electron-emitting characteristics and the electron-emitting efficiency are not always satisfactory, and the operation stability of the image forming apparatus using the same is not always obtained. In fact, it is difficult to say that the properties are necessarily satisfactory.

Therefore, it has good electron emission characteristics,
There has been a demand for realizing an electron-emitting device that can hold this for a long time.

According to the study of the present inventors, one of the main causes of deterioration of the electron emission characteristics of an electron-emitting device (for example, a surface conduction electron-emitting device) having a conductive film having an electron-emitting portion between electrodes is one of the main causes. It was found that this was a change in the conductive film due to driving. The reason for this is that the electron-emitting device is a cold-cathode electron-emitting device as described above, but a relatively large device current If flows through a thin conductive film due to voltage application during driving, and heat is generated near the electron-emitting portion. Temperature rise,
It is considered that this would cause the conductive film to locally melt or agglomerate.

On the other hand, in a heat process (sealing process or the like) at the time of manufacturing a panel, the conductive film may aggregate. Therefore, in order to suppress the deterioration of the electron-emitting device and extend the life, it is desirable to use a material having a high melting point as the material of the conductive film.

However, when a conductive film is formed of a material having a high melting point, a large amount of power is required to form an electron emission portion (energization forming) by the above-described energization process, and as a result, preferable electron emission characteristics are obtained. May not be obtained. Further, when a plurality of electron-emitting devices are arranged on the same substrate as in a display device, and a plurality of devices connected to the same wiring are simultaneously energized and formed, a large current is generated as a whole. Therefore, it is necessary to increase the current capacity of the wiring. In addition, since the voltage drop due to the electrical resistance of the wiring becomes remarkable, the effective voltage applied to each element is different for each element, and there is a problem that uniform forming becomes difficult. Further, even if the above-mentioned problem can be avoided by any method and a high melting point metal can be used as the material of the conductive film, W, Mo, Nb, etc., which can be considered as specific materials, have a relatively large work function. Have.
This is an undesirable property for obtaining a large emission current.

Therefore, it is desired to realize a conductive film which requires a small amount of electric power for energization forming, does not easily dissolve or coagulate, and can obtain a large emission current.

To solve the above-mentioned problem, a method of forming a metal oxide layer having a high melting point on a conductive film has been disclosed (Japanese Patent Application Laid-Open No. 09-102267). According to this, since the conductive thin film is covered with the metal oxide layer, the conductive thin film hardly dissolves or agglomerates, and realizes a conductive film capable of obtaining a large emission current. However, generally, a metal oxide having a high melting point has a high electric resistance,
When a high voltage is applied to an image forming member made of a phosphor to increase the above-mentioned electron emission efficiency, the surface potential of the metal oxide layer becomes unstable in the vicinity of the electron emission portion, and as a result, the electron The choice of material was important because the release characteristics could be unstable.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and suppresses dissolution and aggregation of a conductive thin film, obtains a large emission current, and stabilizes the surface potential of an insulating surface near an electron emission portion. An object of the present invention is to provide an electron-emitting device that maintains good electron-emitting characteristics for a long period of time, an electron source and an image forming apparatus using the same, and a method of manufacturing the same.

[0018]

In order to achieve the above object, the present invention has the following arrangement.

That is, the electron-emitting device of the present invention comprises a pair of opposing device electrodes provided on a base, a conductive thin film provided by electrically connecting the device electrodes, and a conductive film having an electron-emitting portion. And at least a part of the conductive film is coated with a nitride, and usually, the electron-emitting device further includes a deposited layer made of carbon, a carbon compound, or a mixture of both. In the release section.

Here, the nitride coating is preferably formed on the conductive film in a layer having a thickness of 5 to 10 nm.

The materials constituting the nitride thin film include:
B, Al, C, Si, Ge, Ti, Zr, Hf, V, N
It is preferable to include a nitride of at least one metal (or semimetal) element selected from the group consisting of b, Ta, Cr, Mo and W.

The electron source of the present invention is characterized in that a plurality of the above-mentioned electron-emitting devices of the present invention are arranged and formed on a substrate.

An image forming apparatus according to the present invention includes the above-mentioned electron source of the present invention and an image forming member for forming an image by being irradiated with an electron beam emitted from the electron source in a vacuum vessel. It is characterized by the following.

A manufacturing method according to the present invention is a method for manufacturing the above-described electron-emitting device, electron source or image forming apparatus according to the present invention, wherein at least a step of coating at least a conductive thin film with a nitride thin film; It is characterized by including
Usually, an activation step for forming a deposited layer made of carbon, a carbon compound or a mixture of both is performed after the forming step.

As described above, the present invention provides an electron-emitting device,
The configuration and operation of each invention will be described in detail below with respect to an electron source having a plurality of the electron-emitting devices, an image forming apparatus using the same, and a method of manufacturing the same.

[0026]

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.

FIGS. 1A and 1B are schematic views showing the structure of a flat type electron-emitting device to which the present invention can be applied. FIG. 1A is a plan view and FIG. 1B is a cross-sectional view.

In FIG. 1, 1 is a substrate, 2 and 3 are device electrodes, 4 is a conductive film, 5 is an electron emitting portion, 6 is a nitride thin film,
7 is a film of carbon, a carbon compound, or a mixture thereof. Preferably, the nitride thin film 6 is formed so as to cover the entire region of the conductive film 4.

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

The materials of the opposing element electrodes 2 and 3 are as follows.
General conductor materials can be used. This includes, for example, Ni, Cr, Au, Mo, W, Pt, Ti, Al, C
metals or alloys such as u, Pd, and Pd, Ag, A
It can be appropriately selected from a printed conductor composed of a metal such as u, RuO ₂ , Pd-Ag, or a nitride and glass, a transparent conductor such as In ₂ O ₃ —SnO ₂ , and a semiconductor material such as polysilicon. it can.

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 device electrode interval L is preferably several hundred nm to several hundred μm.
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.
A configuration in which a conductive film 4, a nitride thin film 6, and opposing element electrodes 2 and 3 are stacked in this order may be adopted.

The thickness of the conductive film 4 is appropriately set in consideration of the step coverage of the device electrodes 2 and 3, the resistance value between the device electrodes 2 and 3, the forming conditions described later, and the like. It is preferably in the range of several hundred pm to several hundred nm, more preferably in the range of 1 nm to 50 nm. The resistance value is such that Rs is 10 ² to 10 ⁷ Ω / □. Rs is a thickness t, a width w, and a length l.
The resistance R measured in the length direction of the thin film of R = Rs (l / l
w) and Rs = P / t where P is the resistivity. In the specification of the present application, the forming process will be described by exemplifying an energizing process, but the forming process is not limited to these, and includes a process of forming a gap in a film to form a high resistance state. It is.

In the present invention, since the conductive film 4 is covered with a nitride thin film having a high melting point, a material that can form a good electron-emitting portion with relatively small electric power can be selected as the material constituting the conductive film 4. A conductive material such as Au, PdO, Pd, or Pt can be selected.

As a material of the conductive film 4, among the above-mentioned materials, PdO is capable of easily forming a fine particle film by baking an organic PdO compound in the air, and has relatively low electric conductivity because it is a semiconductor. A large process margin with respect to the film thickness for obtaining the resistance value Rs, and the metal Pd can be easily reduced after the formation of the electron-emitting portion;
This is preferable in that the resistance of the conductive film can be reduced. However, the effect of the present invention is not limited to the case where PdO or the above-mentioned material is used.

The electron emitting portion 5 is constituted by a gap formed in a part of the conductive film 4 and preferably a carbon film formed by activation described later. In some cases, conductive fine particles having a particle size in the range of several hundred pm to several tens of nm exist inside the electron emission portion 5. The conductive fine particles contain some or all of the elements of the material constituting the conductive film 4.

In the present invention, the electron-emitting portion 5 may contain a substance similar to some or all of the elements constituting the nitride thin film 6 described below.

The nitride thin film 6 is not limited to a single-element single-element nitride, but may be a multi-element nitride containing a plurality of metals and non-metal elements. Has hardness and high melting point. Thus, the object is to prevent the electron emission characteristics from being deteriorated due to thermal melting or thermal aggregation of the conductive film 4.

The reason for using a nitride thin film is that, besides having a high melting point, carbon and a carbon compound deposited by an activation step described later are filled in a gap formed in a part of the conductive film by the above-described forming step or the like. Low reactivity.

The term "reactivity" as used herein means that carbon and carbon compounds react with constituent elements of other members by heat during the activation step or driving, and are desorbed as compounds having a higher vapor pressure. Including phenomena. Such desorption of carbon and carbon compounds causes deterioration of device characteristics.

In particular, caution was required for oxides, since carbon and carbon compounds may react with oxygen to form carbon monoxide having a high vapor pressure.

The process in which carbon and the carbon compound react with the constituent elements of other members occurs at a portion in direct contact, when the surface of the member is gasified by the influence of electric discharge or the like, and various processes occur. There is a possibility.

In the nitride film of the present invention, nitrogen,
Since it is composed of metals, carbon, boron, etc. that do not generate compounds with high vapor pressure by reaction with carbon and carbon compounds, even if the nitride thin film is partially gasified by the influence of electric discharge, carbon and carbon compounds Is not considered to have the above-mentioned effect.

FIG. 2 schematically shows a state in which the conductive film 4 is covered with the nitride thin film 6 in the present invention. When the nitride thin film 6 is included in the gap between the fine particles constituting the conductive film 4 as shown in FIG. 2A, a thin film is formed on the conductive film 4 as shown in FIG. If so, then Figure 2
As shown in (c), the whole of the fine particles of the conductive film 4 may be covered, and in any case, the present invention is effective.

In the present invention, since the conductive film 4 is covered with the nitride thin film 6 having high hardness and high melting point,
It is possible to form an electron-emitting portion having a small gap width, to suppress melting and aggregation of the conductive film in the vicinity of the electron-emitting portion during driving, and to maintain stable electron-emitting characteristics for a long time. .

As will be described later, the change of the conductive film in the heating step at the time of manufacturing the panel can be suppressed.

When the nitride thin film 6 is contained in the gap between the fine particles constituting the conductive film 4 as shown in FIG. 2A, the content thereof is determined by the ratio between the conductive film 4 and the nitride thin film 6. It is desirable that the molar ratio of the metal element in the nitride in the whole is 50% or less. This is because, if the content is higher than this, the conductivity of the conductive film 4 may be impaired, and the electric power required for the energization forming may increase. When the content is 10% or less, the deterioration of the electron emission characteristics due to melting and aggregation of the conductive film 4 may not be sufficiently suppressed. Therefore, the content is desirably 10% or more.

When the nitride film is formed by covering the conductive film 4 as shown in FIG. 2B, the thickness is preferably 10 nm or less. That is, if the nitride thin film is too thick, the power required for energization forming becomes large, and as a result, the electron emission characteristics become insufficient, and in some cases, the forming cannot be performed. . Furthermore, when the nitride thin film is an insulator,
When the device is driven in a state where a high voltage is applied to an anode electrode described later, the nitride film is charged up, thereby changing the equipotential surface around the device and causing the trajectory of the emitted electrons. May fluctuate.

If the thickness of the nitride thin film is less than 5 nm, it may not be possible to sufficiently suppress the deterioration of the electron emission characteristics due to melting and aggregation of the conductive film.
m or more.

Further, in the case of the configuration as shown in FIG.
A suitable condition is selected from the conditions satisfying the above two conditions. In this case, typical preferable conditions of the nitride thin film 6 are as follows:
For example, the thickness is 5 nm, and it is about 30% to enter the gap between the conductive films 4.

The resistance can be easily adjusted by making the nitride thin film a multi-element nitride containing a plurality of metals and non-metal elements. If the resistance of the nitride film is too low, energization forming cannot be performed, or even if the formation can be performed, current leaks and an appropriate voltage may not be applied to the element. Further, even if the resistance is too high, the element may be deteriorated due to the influence of charging. Therefore, the resistance of the nitride thin film is preferably in the range of 10 ⁴ Ω / □ to 10 ¹⁰ Ω / □.

The nitride thin films satisfying the characteristics described above include B, Al, C, Si, Ge, Ti, Zr, and H.
f, V, Nb, Ta, Cr, Mo, W, a mono-component or a multi-component nitride, and the like.

Among these nitrides, those which are unstable in a high-temperature atmosphere are included. However, the effects of the present invention are not limited by this, and are suitable according to the use environment and purpose. You can choose one.

As a method of forming these nitride thin films 6, there are a sputtering method, a reactive sputtering method, a plasma CVD method, and the like.
It can be formed on the conductive film by a thin film forming means such as a method, an electron beam evaporation method, an ion plating method, and an ion beam assisted evaporation method.

For example, when forming a film of TiN, which is a single metal nitride, by sputtering, a target of Ti or TiN is sputtered in a gas containing nitrogen or ammonia to nitride sputtered metal atoms. A nitride thin film is obtained. By adjusting the sputtering conditions such as the partial pressure of nitrogen or ammonia and the deposition rate, the amount of nitrogen in the nitride thin film changes, but the better the electrical and mechanical stability of the film, the better the nitridation.

When forming a multi-component nitride film, it is possible to use a nitride target whose composition is adjusted in advance.

On the other hand, most of these nitride thin films are electrically insulating. When the conductive film 4 and the electron emitting portion 5 are covered with an insulating nitride, if the film thickness is too large, electron emission may be hindered and the characteristics may be adversely affected. In addition, as described above, after being emitted from the electron emitting portion, the electrons are charged up by the electrons incident on the conductive film, which may cause a problem in use.

Further, when conductivity is given to the nitride thin film, if the conductivity of the nitride thin film cannot be ignored with respect to the conductivity of the conductive film, the power required for the energization forming process becomes large. Problem also arises.

As a result of examining the above circumstances,
Even if the nitride thin film is insulative, the thickness of the film formed by the nitride thin film 6 may be 3 nm or more and 10 nm or less. Within this range, there is little adverse effect on the electron emission characteristics, and the effect of suppressing the deterioration of the characteristics due to driving is exhibited. However, it is considered that suitable conditions may vary depending on the form, density, etc. of the nitride, and the above conditions are not necessarily absolute.

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

FIG. 3 is a schematic view showing an example of the vertical electron-emitting device of the present invention.

In FIG. 3, the same parts as those shown in FIG. 1 are denoted by the same reference numerals as those shown in FIG.
21 is a step forming part. The substrate 1, the device electrodes 2 and 3, the conductive film 4, the electron-emitting portion 5, and the nitride thin film 6
It can be made of the same material as in the case of the above-mentioned 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 is
The range can be several hundred nm to several tens of μm, corresponding to the element electrode interval L of the flat-type electron emission element described above. 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, but 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. Although the electron-emitting portion 5 is formed on the side end surface of the step forming portion 21 in FIG. 3, the shape and position are not limited to this, depending on manufacturing conditions, forming conditions and the like.

Various methods are conceivable as a method for manufacturing the above-described electron-emitting device. One example of the method for manufacturing the electron-emitting device shown in FIG. 1 will be described with reference to FIG. In FIG. 4, the same reference numerals as those in FIG. 1 indicate the same members.

1) The substrate 1 is sufficiently washed with a detergent, pure water, an organic solvent, and the like, and after the element electrode material is deposited by a vacuum deposition method, a sputtering method, or the like, the substrate 1 is formed on the substrate 1 by using, for example, a photolithography technique. The device electrodes 2 and 3 are formed (FIG. 4A).

2) An organic metal solution is applied to the substrate 1 provided with the device electrodes 2 and 3 to form an organic metal thin film. The organic metal solution is a solution of an organic metal compound containing the metal of the material of the conductive film 4 as a main element. The organic metal thin film is heated and baked, and patterned by lift-off, etching, or the like to form the conductive film 4. Here, the method of applying the organometallic solution has been described, but the method of forming the conductive film 4 is not limited to this, and a vacuum evaporation method, a sputtering method, a CVD method, a dispersion coating method, a dipping method, a spinning method, or the like. A coating method or the like can also be used. Next, a nitride thin film 6 having a higher hardness and a higher melting point than the material of the conductive film 4 is formed on the substrate 1 on which the conductive film 4 is formed by a sputtering method (FIG. 4).
(B)). In the present invention, it is preferable that the nitride thin film 6 is formed so as to cover the entire region of the conductive film 4, and it is not particularly necessary to pattern the conductive film 4 into a specific shape. 4 and patterning can be performed simultaneously. Here, the method of forming the nitride thin film 6 has been described by using the sputtering method, but the method is not limited to the sputtering method. The reactive sputtering method, the plasma CVD method, the electron beam evaporation method, the ion plating method, the ion beam assist method, The nitride thin film 6 can be formed on the conductive film 4 by a thin film forming means such as an evaporation method.

3) Subsequently, a forming step is performed. As an example of the method of the forming step, a method using an energization process will be described. However, the forming step according to the present invention is not limited to this, and any method may be used as long as a gap is formed in the conductive film 4. When current is applied between the device electrodes 2 and 3 using a power supply (not shown), a first gap 8 is formed in a part of the conductive film 4 and the nitride film 6 (FIG. 4C). . According to the energization forming, a portion of the conductive film 4 where a structure such as destruction, deformation or alteration is locally changed is formed. The portion constitutes an electron emission portion (5 in FIG. 1). As described above, when the nitride thin film 6 is formed before the energization forming, the nitride thin film 6 may also locally undergo structural changes such as destruction, deformation, or alteration. FIG. 5 shows an example of the voltage waveform of the energization forming. The voltage waveform is preferably a pulse waveform. For this purpose, a method shown in FIG. 5A in which a pulse with a constant pulse peak value is applied continuously and a method shown in FIG. 5B in which a voltage pulse is applied while increasing the pulse peak value are used.
There is a method shown in T1 and T in FIG.
2 is the pulse width and pulse interval of the voltage waveform. Normal T1
Is 1 μsec to 10 msec, and T2 is 10 μsec to 1
It is set in the range of 00 msec. The peak value of the triangular wave (peak voltage at the time of energization forming) 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 of minutes in a vacuum atmosphere of an appropriate pressure of about 1.3 × 10 ⁻³ Pa or less. The pulse waveform is not limited to a triangular wave, and a desired waveform such as a rectangular wave can be adopted. Further, the pulse crest value, pulse width, pulse interval, and the like are not limited to the above-mentioned values, and appropriate values can be selected so that the electron-emitting portion is formed well. FIG.
T1 and T2 in (b) can be the same as those shown in FIG. The peak value of the triangular wave (peak voltage during energization forming) can be increased, for example, by 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 while the pulse for forming is off, and measuring the current. it can. For example, it is preferable to measure the element current flowing when a voltage of about 0.1 V is applied, determine the resistance value, and terminate the energization forming when the resistance value is 1 MΩ or more.

4) The element after the forming is subjected to a process called an activation step. The activation step is a step in which the element current If and the emission current Ie are significantly changed by this step. The activation step can be performed, for example, by repeatedly applying a pulse in an atmosphere containing a gas of an organic substance, similarly to the energization forming. This atmosphere can be formed by using an organic gas remaining in the atmosphere when the inside of the vacuum vessel is evacuated using, for example, an oil diffusion pump or a rotary pump, or once sufficiently evacuated by an ion pump or the like. It can also be obtained by introducing a gas of an appropriate organic substance into a vacuum. The preferable gas pressure of the organic substance at this time varies depending on the above-described application form, the shape of the vacuum vessel, the type of the organic substance, and the like, and is appropriately set according to the case. Suitable organic materials include
Alkanes, alkenes, aliphatic hydrocarbons of alkynes, aromatic hydrocarbons, alcohols, aldehydes, ketones, amines and phenols, carboxylic acids, organic acids such as sulfonic acids can be mentioned. Is a saturated hydrocarbon represented by C _n H _{2n + 2} such as methane, ethane and propane; an unsaturated hydrocarbon represented by a composition formula such as C _n H _2n such as ethylene and propylene; benzene, toluene;
Methanol, ethanol, formaldehyde, acetaldehyde, acetone, methyl ethyl ketone, methylamine, ethylamine, phenol, formic acid, acetic acid, propionic acid and the like or a mixture thereof can be used. By this treatment, carbon, a carbon compound, or a mixture thereof (7 in FIG. 4D) is converted from organic substances existing in the atmosphere.
By depositing on the nitride film 6 and the conductive film 4 and forming a second gap 9 narrower than the first gap 8 on the substrate 1 in the first gap 8 formed by the forming. , The device current If and the emission current Ie significantly increase.
In the figure, the first gap 8 and the second gap 9 are schematically illustrated as completely separated from each other, but may be partially connected (FIG. 4D). .

The termination of the activation step is appropriately determined while measuring the device current If and the emission current Ie. The pulse width, pulse interval, pulse crest value, and the like are set as appropriate.
The carbon, carbon compound or a mixture of both deposited on the device is, for example, graphite (so-called HOPG, P
G, GC. HOPG is a crystal structure of almost perfect graphite, PG is a crystal having a crystal grain of about 20 nm and slightly disordered, and GC is a crystal having a grain of about 2 nm and disorder of the crystal structure is further increased). Amorphous carbon (refers to amorphous carbon and a mixture of amorphous carbon and the aforementioned microcrystals of graphite)
The thickness is preferably in the range of 50 nm or less, more preferably in the range of 30 nm or less.

5) The electron-emitting device obtained through the above steps is preferably subjected to a stabilization 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 and an ion pump can be used. In the activation step, when an oil diffusion pump or a rotary pump is used as an exhaust device and an organic gas derived from an oil component generated from the oil diffusion pump or the rotary pump is used, the partial pressure of this component needs to be suppressed as low as possible. The partial pressure of the organic component in the vacuum vessel is 1.3 × 1 which is a partial pressure at which the above-mentioned carbon, carbon compound or a mixture of both is hardly newly deposited.
0 ^-6 Pa or less, more preferably 1.3 × 10 ^-8 Pa
The following are particularly preferred. Further, when the inside of the vacuum vessel is evacuated, it is preferable to heat the entire vacuum vessel so that the organic substance molecules adsorbed on the inner wall of the vacuum vessel and the electron-emitting device can be easily evacuated. The heating conditions at this time are desirably 80 to 250 ° C., preferably 150 ° C. or more, and it is desirable to perform the treatment for as long as possible. However, the present invention is not particularly limited to this condition, and the size and shape of the vacuum vessel, the configuration of the electron-emitting device, etc. This is performed under conditions appropriately selected according to various conditions such as the above. The pressure in the vacuum vessel needs to be as low as possible, and is preferably 1 × 10 ⁻⁵ Pa or less, and particularly preferably 1.3 × 10 ⁻⁶ Pa or less. After performing the stabilization step, the atmosphere at the time of driving is preferably to maintain the atmosphere at the end of the stabilization process, but is not limited to this.If the organic substance is sufficiently removed,
Even if the degree of vacuum itself is slightly reduced, sufficiently stable characteristics can be maintained. By adopting such a vacuum atmosphere, the deposition of new carbon, a carbon compound, or a mixture of both can be suppressed, and H ₂ O, O ₂ , and the like adsorbed on a vacuum vessel or a substrate can be removed. Current I
f, the emission current Ie is stabilized.

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

FIG. 6 is a schematic view showing an example of a vacuum processing apparatus. This vacuum processing apparatus also has a function as a characteristic evaluation apparatus. In FIG. 6 as well, the same parts as those shown in FIG. 1 are denoted by the same reference numerals as in FIG. In FIG. 6, 55 is a vacuum container, and 56 is an exhaust pump. An electron-emitting device is provided in the vacuum vessel 55. That is, 1 is a substrate constituting an electron-emitting device, 2 and 3 are device electrodes, 4 is a conductive film, 5 is an electron-emitting portion, and 6 is a nitride thin film. 51 is a power supply for applying a device voltage Vf to the electron-emitting device, 50 is an ammeter for measuring a device current If flowing through the conductive film 4 between the device electrodes 2 and 3, and 54 is an electron-emitting portion of the device. This is an anode electrode for supplementing the emission current Ie emitted from the anode.
Reference numeral 53 denotes a high-voltage power supply for applying a voltage to the anode electrode 54, and reference numeral 52 denotes an ammeter for measuring an emission current Ie emitted from the electron emission portion 5 of the device. As an example, the measurement can be performed with the voltage of the anode electrode in the range of 1 kV to 10 kV and the distance H between the anode electrode and the electron-emitting device in the range of 2 mm to 8 mm.

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 includes a normal high vacuum device system including a turbo pump and a rotary pump, and an ultra-high vacuum device system including an ion pump and the like.
The entire vacuum processing apparatus provided with the electron source substrate shown here can be heated by a heater (not shown). Therefore,
When this vacuum processing apparatus is used, the steps after the above-described energization forming can also be performed.

FIG. 7 shows emission current Ie, device current If and device voltage V measured using the vacuum processing apparatus shown in FIG.
It is the figure which showed the relationship of f typically. In FIG.
Since the emission current Ie is significantly smaller than the element current If, it is shown in arbitrary units. The vertical and horizontal axes are linear scales.

As is clear from FIG. 7, the electron-emitting device of the present invention has three characteristic properties with respect to the emission current Ie. (I) In the electron-emitting device of the present invention, when a device voltage higher than a certain voltage (referred to as a threshold voltage, Vth in FIG. 7) is applied, the emission current Ie sharply increases, while the threshold voltage Vth
Below, the emission current Ie is hardly detected. That is, it is a nonlinear element having a clear threshold voltage Vth with respect to the emission current Ie. (Ii) Since the emission current Ie depends monotonically on the device voltage Vf, the emission current Ie can be controlled by the device voltage Vf. (Iii) The emission charge captured by the anode electrode 54 is:
It depends on the time for applying the element voltage Vf. 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.

FIG. 7A shows an example in which the element current If monotonically increases with respect to the element voltage Vf (hereinafter referred to as “MI characteristic”). FIG. 7B shows the element current If.
Shows a voltage control type negative resistance characteristic (hereinafter referred to as “VCNR characteristic”) with respect to the element voltage Vf. Which characteristic is exhibited depends on the manufacturing method of the electron-emitting device, the measurement conditions of the measuring device, and the like. However, even when the device current If shows VCNR characteristics with respect to the device voltage Vf, the emission current Ie shows MI characteristics with respect to the device voltage Vf.

FIG. 8 schematically shows a temporal change of the emission current Ie when driving for a long time while applying a constant pulse voltage to a constant element. In the figure, the solid line shows the characteristics of the device of the present invention, and the broken line shows the characteristics of a comparative device without forming a nitride thin film. Thus, in the device of the present invention, the electron emission characteristics are stably maintained for a long time. This is because the electron emitting portion 5 is formed by the nitride thin film 6.
It is presumed that deterioration due to aggregation or the like of the conductive film 5 in the vicinity of is suppressed.

As described above, due to the characteristics of the electron-emitting device of the present invention, even in an electron source in which a plurality of devices are arranged on a substrate and an image forming apparatus using the same, the emitted electrons can be easily formed in accordance with an input signal. The amount can be controlled, and electrons can be stably emitted over a long period of time, so that good image formation can be performed, and application to various fields is expected.

Next, as an example of the electron source of the present invention, an electron source having a plurality of the above-described electron-emitting devices will be described. First, the arrangement of the electron-emitting devices will be described.

Various arrangements of the electron-emitting devices can be adopted.

As an example, a large number of rows of electron-emitting devices connected to wirings at both ends of each of a large number of electron-emitting devices arranged in parallel (referred to as a row direction) are arranged in a direction perpendicular to the wiring (column direction). In some cases, a control electrode (also referred to as a grid) disposed above the electron-emitting device controls the electrons from the electron-emitting device in a ladder-like arrangement. 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 the characteristics (i) to (iii) as described above. In other words, the electrons emitted from the 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 threshold voltage is exceeded. On the other hand, when the voltage is equal to or lower than 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 of the devices, the electron-emitting device is appropriately selected according to an input signal to reduce the amount of electron emission. Can be controlled independently.

Hereinafter, based on this principle, an electron source substrate obtained by disposing a plurality of electron-emitting devices to which the present invention can be applied will be described with reference to FIG. In FIG. 9, the substrate 1 is a glass substrate as described above, and the number and shape of the electron-emitting devices 104 arranged on the substrate 1 are appropriately set according to the application.

The m X-direction wirings 102 are Dx1, Dx
2... Dxm, and can be formed of a conductive metal or the like formed on the substrate 1 by a vacuum deposition method, a printing method, a sputtering method, or the like. Also, many electron-emitting devices 104
The material, thickness, and width of the wiring are appropriately designed so that the voltage is supplied substantially uniformly. Y direction wiring 103 is Dy
1, Dy2... Dyn are formed in the same manner as the X-direction wiring 102. An interlayer insulating layer (not shown) is provided between the m X-directional wirings 102 and the n Y-directional wirings 103 to electrically separate them. Note that m and n are both positive integers.

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 1 on which the X-directional wiring 102 is formed. In particular, the film thickness and the material are selected so as to withstand the potential difference at the intersection of the X-directional wiring 102 and the Y-directional wiring 103. The production method is appropriately set. The X-direction wiring 102 and the Y-direction wiring 103 are respectively drawn out as external terminals.

A pair of opposing electrodes (not shown) constituting the emission element 104 are composed of m X-directional wirings 102 and n Y electrodes.
The directional wiring 103 is electrically connected to the wiring 105 made of a conductive metal or the like.

Here, m X-directional wires 102 and n Y wires
Some or all of the constituent elements of the material forming the directional wiring 103, the material forming the connection 105, and the material forming the pair of element electrodes may be the same or different. These materials are appropriately selected, for example, from the above-described materials for the device electrodes. When the material forming the device electrode is the same as the material of the connection 105 and the wires 102 and 103, the wires 102 and 10 connected to the device electrode are used.
3 and the like may be collectively referred to as element electrodes. The electron-emitting device 104 may be formed on the substrate 1 or on an interlayer insulating layer (not shown).

As will be described later in detail, a scanning signal applying means (not shown) for applying a scanning signal for selecting a row of the emission elements 104 arranged in the X direction is electrically connected to the X-direction wiring 102. Connected.

On the other hand, the Y-direction wiring 103 is electrically connected to a modulation signal generating means (not shown) for modulating each column of the electron-emitting devices 104 arranged in the Y-direction according to an input signal. 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.

Next, an image forming apparatus constructed using the above-described electron sources having a simple matrix arrangement will be described with reference to FIG.
This will be described with reference to FIG. FIG. 10 is a schematic diagram illustrating an example of a display panel of the image forming apparatus, and FIG.
FIG. 3 is a schematic diagram of a fluorescent film used in the image forming apparatus of No. 0;
FIG. 12 is a block diagram illustrating an example of a driving circuit for performing display according to an NTSC television signal.

In FIG. 10, reference numeral 1 denotes a substrate of an electron source having a plurality of electron-emitting devices as described above, 111 denotes a rear plate to which the substrate 1 is fixed, and 116 denotes a fluorescent film 114 and a metal back 115 on the inner surface of a glass substrate 113. And the like are formed on the face plate. Reference numeral 112 denotes a support frame. On the support frame 112, the rear plate 111 and the face plate 116 are coated with a low-melting frit glass or the like.
The envelope 118 is sealed by baking at 500 ° C. for 10 minutes or more.

In the present invention, since the conductive film made of, for example, a fine particle film is covered with a nitride thin film having a high melting point, it does not melt or agglomerate even at high temperature sealing. In addition,
The atmosphere for firing the frit glass can be performed in the air, in nitrogen, or in an inert gas, depending on the properties of the nitride thin film.

In FIG. 10, reference numerals 102 and 103 denote X-direction wiring and Y-direction wiring connected to a pair of device electrodes 2 and 3 of the electron-emitting device 104, respectively having external terminals Dx1 to Dxm and Dy1 to Dyn. I have.

The envelope 118 includes the face plate 116, the support frame 112, and the rear plate 111, as described above. Since the rear plate 111 is provided mainly for the purpose of reinforcing the strength of the substrate 1, if the substrate 1 itself has sufficient strength, the separate rear plate 111 can be unnecessary. That is, the support frame 112 may be directly sealed to the substrate 1, and the envelope 118 may be configured by the face plate 116, the support frame 112, and the substrate 1. On the other hand, by providing a support (not shown) called a spacer between the face plate 116 and the rear plate 111, the envelope 118 having sufficient strength against atmospheric pressure can be configured.

The fluorescent film 114 can be composed of only a phosphor in the case of monochrome. In the case of a color fluorescent film, black stripes (FIG. 1)
1 (a)) or black matrix (FIG. 11 (b))
And the like, and can be composed of a black conductive material 121 and a phosphor 122. The purpose of providing the black stripes and the black matrix is to make the color separation between the phosphors 122 of the necessary three primary color phosphors black in the case of color display so that color mixing and the like become inconspicuous.
14 is to suppress a decrease in contrast due to reflection of external light. Black conductive material 1 such as black stripe
As the material 21, besides a commonly used material containing graphite as a main component, a material having conductivity and low transmission and reflection of light can be used.

The method of applying the phosphor 122 to the glass substrate 113 can employ a precipitation method, a printing method, or the like irrespective of monochrome or color. Usually, a metal back 115 is provided on the inner surface side of the fluorescent film 114. Metal back 115
The purpose of this is to improve the brightness by mirror-reflecting the light toward the inner surface side of the light emitted from the phosphor 122 toward the face plate 116, to act as an electrode for applying an electron beam acceleration voltage, The phosphor 1 is damaged by the collision of the negative ions generated in the enclosure 118.
22 is protected. Metal back 115
After the formation of the fluorescent film 114, a smoothing process (usually called “filming”) of the inner surface of the fluorescent film 114 is performed,
Thereafter, it can be manufactured by depositing Al using vacuum evaporation or the like.

The face plate 116 may be provided with a transparent electrode (not shown) on the outer surface side of the fluorescent film 114 in order to further increase the conductivity of the fluorescent film 114.

When the above-mentioned sealing is performed, in the case of color, the phosphors of each color and the electron-emitting devices must be opposed to each other, so that it is necessary to perform sufficient alignment.

The interior of the envelope 118 is evacuated by an oil-free exhaust device such as an ion pump and a sorption pump while appropriately heating the interior of the envelope 118 in the same manner as in the stabilization step for the individual electron-emitting devices 104 described above. After being evacuated through a pipe to make the atmosphere of a pressure of about 10 ⁻⁵ Pa and an organic substance-poor atmosphere, it is sealed. Also, a getter process can be performed to maintain the pressure after the envelope 118 is sealed. This is because the envelope 1 is sealed by resistance heating, high-frequency heating, or the like immediately before or after the envelope 118 is sealed.
This is a process of heating a getter (not shown) disposed at a predetermined position in the substrate 18 to form a deposited film. Getter is usually B
a is a main component, and is for maintaining a pressure of, for example, 10 ⁻³ to 10 ⁻⁵ Pa by the adsorption action of the deposited film.

The manufacturing steps of the electron-emitting device after the above-described forming process can be performed in a vacuum processing apparatus or after the envelope 118 is sealed.
An appropriate step is selected depending on the purpose. The contents are in accordance with the procedure described above for the method of manufacturing the individual electron-emitting devices.

An example of the configuration of a driving 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.
1 is an image display panel, 202 is a scanning circuit, 203 is a control circuit, and 204 is a shift register. 205 is a line memory, 206 is a synchronizing signal separation circuit, 207 is a modulation signal generator, and Vx and Va are DC voltage sources.

The display panel 201 has terminals Dx1 to Dx1
xm, terminals Dy1 to Dyn, and a high voltage terminal Hv are connected to an external electric circuit. Terminals Dx1 to Dxm are provided with scanning for sequentially driving electron sources provided in the display panel 201, that is, electron emission element groups arranged in a matrix of m rows and n columns, one row (n elements) at a time. A signal is applied.

To the terminals Dy1 to Dyn, a modulation signal for controlling the output electron beam of each of the electron-emitting devices in one row selected by the scanning signal is applied. For example, 10 kV from the DC voltage source Va is applied to the high voltage terminal Hv.
This is an accelerating voltage for applying sufficient energy to the electron beam emitted from the electron-emitting device to excite the phosphor.

The scanning circuit 202 will be described. This circuit includes M switching elements inside (in the drawing, S1 to Sm are schematically shown). Each switching element selects either the output voltage of the DC voltage source Vx or 0 V (ground level), and is electrically connected to the terminals Dx1 to Dxm of the display panel 201. Each of the switching elements S1 to Sm operates based on a control signal Tscan output from the control circuit 203, and can be configured by combining switching elements such as FETs, for example.

The control circuit 203 has a function of matching the operation of each section so that appropriate display is performed based on an image signal input from the outside. The control circuit 203 generates control signals Tscan, Tsft, and Tmry for each unit based on the synchronization signal Tsync sent from the synchronization signal separation circuit 206.

The synchronizing signal separation circuit 206 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 separation (filter) circuit or the like. Can be configured. The synchronizing signal separated by the synchronizing signal separating circuit 206 includes a vertical synchronizing signal and a horizontal synchronizing signal, but is shown here as a Tsync signal for convenience of explanation. The luminance signal component of the image separated from the television signal is referred to as a DATA signal for convenience. The DATA signal is input to the shift register 204.

The shift register 204 is for serially / parallel converting the DATA signal input serially in time series for each line of an image, and is based on a control signal Tsft sent from the control circuit 203. (Ie, the control signal Tsft can be said to be a shift clock of the shift register 204).
The data of one line of the serial / parallel-converted image (corresponding to drive data for n electron-emitting devices) is Id
The shift register 204 outputs n parallel signals of 1 to Idn.

The line memory 205 is a storage device for storing data for one line of an image for a required time, and stores the contents of Id1 to Idn as appropriate according to a control signal Tmry sent from the control circuit 203. The stored contents are output as I'd1 to I'dn and input to the modulation signal generator 207.

The modulation signal generator 207 outputs the image data I '
The signal source is a signal source for appropriately driving and modulating each of the electron-emitting devices in accordance with each of d1 to I'dn, and its output signal is supplied to the display panel 20 through terminals Dy1 to Dyn.
1 is applied to the electron-emitting devices.

As described above, the electron-emitting device to which the present invention can be applied has the following basic characteristics with respect to the emission current Ie. That is, a clear threshold voltage Vth is required for electron emission.
And electron emission occurs only when a voltage higher than Vth is applied. For a voltage equal to or higher than the electron emission threshold, the emission current also changes according to the change in the voltage applied to the device. From this, when applying a pulsed voltage to this element,
For example, when a voltage lower than the electron emission threshold is applied, electron emission does not occur, but when a voltage higher than the electron emission threshold is applied, an electron beam is output. At this time, the intensity of the output electron beam can be controlled by changing the pulse peak value Vm. Also, 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 employed. When implementing the voltage modulation method, a circuit of the voltage modulation method that generates a voltage pulse of a fixed length and appropriately modulates the peak value of the pulse according to input data is used as the modulation signal generator 207. be able to.

In implementing the pulse width modulation method,
As the modulation signal generator 207, a pulse width modulation type circuit that generates a voltage pulse having a constant peak value and appropriately modulates the width of the voltage pulse according to input data can be used.

The shift register 204 and the line memory 20
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.

That is, when the digital signal type is used,
It is necessary to convert the output signal DATA of the synchronization signal separation circuit 206 into a digital signal.
A / D converter may be provided. In this connection, the circuit used for the modulation signal generator 207 is slightly different depending on whether the output signal of the line memory 205 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 207 includes, for example, D / D
An 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 207 includes, for example, a high-speed oscillator, a counter for counting the number of waves output from the oscillator, and a comparator for comparing the output value of the counter with the output value of the memory. (Comparator) is used. If necessary, an amplifier for amplifying the pulse width modulated signal output from the comparator to the drive voltage of the electron-emitting device can be added.

On the other hand, in the case of the voltage modulation method using an analog signal, an amplification circuit using, for example, an operational amplifier can be used as the modulation signal generator 207, and a level shift circuit and the like can be added as necessary. . In the case of the pulse width modulation method, for example, a voltage controlled oscillator (VOC)
And, if necessary, an amplifier for amplifying the voltage up to the drive voltage of the electron-emitting device can be added.

The image forming apparatus of the present invention having the display panel 201 and the driving circuit as described above has the external terminal Dx1
By applying a voltage through Dxm and Dy1 to Dyn, electrons can be emitted from necessary electron-emitting devices, and the metal back 1
15 or a high voltage is applied to a transparent electrode (not shown) to accelerate the electron beam, and the accelerated electrons collide with the fluorescent film 114 to emit light, and the television is transmitted according to an NTSC television signal. Display can be performed.

The configuration described above is a schematic configuration necessary for obtaining the image forming apparatus of the present invention, and various modifications are possible based on, for example, the technical idea of the present invention.
Although the input signals are described in the NTSC system, the input signals are not limited to these, and PAL, SECA
In addition to the M type, TV with more scanning lines
Signal (for example, high quality T including MUSE method)
V) system can also be adopted.

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

FIG. 13 is a schematic diagram showing an example of a ladder-type electron source. In FIG. 13, 1 is a substrate, 104
Denotes an electron-emitting device. Reference numeral 304 denotes a common wiring for connecting the electron-emitting devices 104, each of which has external terminals D1 to D10.
have. A plurality of electron-emitting devices 104 are arranged in parallel on the substrate 1 and are called element rows. A plurality of the element rows are arranged to form an electron source.

By applying an appropriate drive voltage between the common wiring 304 of each element row (for example, the common wiring 304 of the external terminals D1 and D2), each element row can be driven.
That is, a voltage equal to or higher than the electron emission threshold is applied to an element row that wants to emit an electron beam, and a voltage equal to or lower than the electron emission threshold is applied to an element row that does not emit an electron beam. Common wiring between the element rows, that is, adjacent external terminals D2 and D3,
Common wiring 304 for D4 and D5, D6 and D7, D8 and D9
Can be integrated as the same wiring.

FIG. 14 is a schematic diagram showing the structure of a display panel 301 provided with the ladder-shaped electron sources. 30
2 is a grid electrode, 303 is an opening through which electrons pass, and D1 to Dm are external terminals for applying a voltage to each electron-emitting device. Gn, G2,... Gn are external terminals connected to the grid electrode 302. Further, the common wiring 304 between each element row is formed on the substrate 1 as an integral same wiring.

In FIG. 14, FIGS.
Are given the same reference numerals as those shown in these figures.

A major difference between the display panel shown here and the display panel using the electron sources having the simple matrix arrangement shown in FIG. 10 is that a grid electrode 302 is provided between the substrate 1 and the face plate 116. It is. The grid electrode 302 is for modulating the electron beam emitted from the electron-emitting device 104. In order to allow the electron beam to pass through a striped electrode provided orthogonally to the ladder-shaped element row, One circular opening 303 is provided for each element. Grid electrode 302
Are not limited to those shown in FIG. For example, a large number of passage openings may be provided in a mesh shape as the openings 303, and the grid electrode 302 may be provided around or near the electron-emitting device 104.

External terminals D1 to Dm and G1 to Gn are
It is electrically connected to a control circuit (not shown).

By simultaneously applying a modulation signal for one image line to the column of the grid electrode 302 in synchronization with sequentially driving (scanning) the element rows one by one,
By controlling the irradiation of each electron beam to the phosphor, an image can be displayed line by line.

As described above, the image forming apparatus of the present invention
It can be obtained using any of the electron sources of the present invention in a simple matrix arrangement or a ladder arrangement, and is suitable not only for the above-described television broadcast display device, but also as a video conference system or a display device such as a computer. A device is obtained. Further, in combination with a photosensitive drum or the like, it can be used as an exposure device of an optical printer.

[0129]

EXAMPLES The present invention will be described below with reference to specific examples. However, the present invention is not limited to these examples, and each element is set within a range in which the object of the present invention is achieved. And that the design is changed.

[Embodiment 1] This embodiment is different from the embodiment shown in FIG.
This is an electron-emitting device having a configuration similar to that schematically shown in FIG. A method for manufacturing the electron-emitting device of this embodiment will be described with reference to FIGS. Step-a A 0.5 μm-thick silicon oxide film was formed on a cleaned blue plate glass by a sputtering method to obtain a substrate 1. A photoresist (RD-2000N-41: manufactured by Hitachi Chemical Co., Ltd.) was applied thereon, and a resist pattern having openings corresponding to the shapes of the device electrodes 2 and 3 was formed by a usual photolithography technique. After sequentially depositing 5 nm-thick Ti and 100 nm-thick Ni thereon by a vacuum evaporation method, the resist pattern was dissolved with an organic solvent, and the device electrodes 2 and 3 were formed by lift-off (FIG. 4A). . The element electrode interval L is 3 μm, and the element electrode length W is 300 μm.
And

Step-b Subsequently, a Cr film having a thickness of 100 nm was deposited by a vacuum evaporation method, and an opening corresponding to the shape of the conductive film 4 was formed by a photolithography technique. A solution of an organic Pd compound (ccp-4230: manufactured by Okuno Pharmaceutical Co., Ltd.) was applied thereon using a spinner, and was heated and baked at 300 ° C. for 12 minutes in the air. Next, the Cr film was removed by wet etching, and a conductive film 4 having a desired pattern was formed by lift-off. The conductive film 4 was a fine particle film containing Pd as a main element, the film thickness was 10 nm, and the resistance value was Rs = 2 × 10 ⁴ Ω / □.

Step-c The above element was set in a vacuum film forming apparatus, and a TiN nitride thin film 6 was formed on the conductive film (FIG. 4B).

The nitride thin film TiN in this embodiment was formed by sputtering a Ti target in a mixed atmosphere of argon and nitrogen using a sputtering apparatus. At this time, the composition was adjusted by changing the power applied to the target.

The thickness of the TiN nitride thin film of this embodiment is 5 n
m, and sheet resistance was 8.1 × 10 ⁹ Ω / □. The sheet resistance is such that a gap L = 5 μm and a length W =
A 10 cm comb-shaped electrode was formed, and a Ti electrode was formed under the same electrode under the same conditions.
After forming N, a value measured by a tester was 4.1 × 10 ^5.
Calculated by converting from Ω. When a sample formed on a silicon substrate under the same conditions was subjected to surface analysis by XPS (X-ray photoelectron spectroscopy), the proportion of Ti present as nitride ([titanium nitride] / [titanium nitride + titanium oxide])
Was 79%.

Step-d Next, the element was placed in a vacuum device 55, a pulse voltage was applied between the element electrodes 2 and 3 by a power source 51, and an energization forming process was performed to form an electron emission portion 5.

The applied pulse waveform is a pulse whose peak value gradually increases as shown in FIG. 5B, but the waveform is not a triangular wave but a rectangular wave. The pulse width T1 was 1 msec, and the pulse interval T2 was 10 msec. In addition, a resistance measuring pulse (not shown) having a peak value of 0.1 V was inserted during the rest period (between pulses) of the forming pulse, and the application of the pulse was terminated when the resistance value exceeded 1 MΩ.

The forming power (power at the time when the current flowing through the element is maximized) is about 70 mW. For comparison, the same as in this embodiment except that the nitride thin film 6 was not formed, for comparison. The value was about 1.3 times that of the manufactured device.

Thereafter, the device was kept at 150 ° C. for 5 hours to reduce PdO of the conductive film to Pd.

Step-e Subsequently, n-hexane was introduced into the vacuum device 55 through an introduction pulse (not shown), and the pressure was set to 1.3 × 10 ⁻³ Pa. Subsequently, a rectangular wave pulse having a peak value of 14 V, a pulse width T1 of 1 msec, and a pulse interval T2 of 10 msec was applied between the device electrodes 2 and 3 to perform an activation process.

At this time, the device current If and the emission current Ie were measured, and the electron emission efficiency η (= Ie / If) was obtained in about 30 minutes.
Since the peak was shown, the application of the pulse voltage and the introduction of n-hexane were stopped, and the activation treatment was completed (FIG. 4D).

The measurement of the electron emission characteristics of the electron-emitting device manufactured as described above was continuously performed by the above-described evaluation apparatus. The distance H between the anode electrode 54 and the electron-emitting device is 4 m
m, the potential difference is 5 kV, and the pressure in the vacuum device 55 is 1.3 ×
The measurement was performed by applying a pulse voltage having a peak value of 14 V at 10 ⁻⁴ Pa.

The time-dependent change of the emission current Ie was compared between the device of this example and a comparative device manufactured by performing the same processing as that of this example except that titanium nitride was not coated. As shown schematically in FIG. 8, the decrease of Ie in the device of this example was smaller than that of the comparative device. It should be noted that the value of Ie in FIG. 8 is shown as a ratio to Ie of each element at the start of measurement, and that Ie of both elements does not initially have the same value.

After the measurement was completed, the vicinity of the electron emission portions of both devices was observed with a high-resolution scanning electron microscope (SEM). However, the device of this example did not show a significant difference from the device before the evaluation.

Separately from the above-mentioned devices, devices having a thickness of 1, 3, (5), 7, 10, 20, and 30 nm of the nitride thin film 6 were manufactured and evaluated in the same manner as described above. Of these devices, energization forming is extremely difficult for devices having a thickness of the nitride thin film 6 of 20 nm or more, and a forming process was attempted on a plurality of devices, but some devices could not form an electron-emitting portion.
An element having a thickness of 10 nm has a forming power of about 0.1.
W, and the emission current Ie was smaller than that of the device of the above embodiment. However, when the peak value of the applied voltage pulse at the time of the step-e and the characteristic measurement was increased to 25 V, stable characteristics almost similar to those of the above example were exhibited. In the device having a thickness of 3 nm, the magnitude of Ie was almost the same as that of the above example, but the change with time of Ie was slightly large. Film thickness is 1n
In the device of m, no improvement was seen in the magnitude of the change over time of Ie as compared with the device for comparison. In the device having a thickness of 30 nm, electron emission was not observed unless the pulse peak value was increased to 40 V.

In the device having a film thickness of 7 nm or more, the temporal decrease of Ie was further smaller than in the device having a film thickness of 5 nm. The value of η = Ie / If gradually increased between 5 and 10 nm in film thickness. This is high hardness on the conductive film,
Due to the formation of TiN having a high melting point, an electron-emitting portion having a narrow crack width 8 is formed during forming, and crack retreat due to heat generation during element driving, that is, thermal aggregation of the conductive film is suppressed. it is conceivable that.

In addition, in a device having a thickness of 20 nm, the emission current often became unstable. This is because the thickness of the nitride thin film was increased, and the charge of the electrons absorbed upon collision with the nitride thin film was increased. It is presumed that the charge does not sufficiently flow into the conductive film 4 to cause charge-up, which may cause a phenomenon such as making the trajectory of the emitted electrons unstable.

From the above results, it was found that the thickness of the nitride thin film made of TiN was more preferably in the range of 5 to 10 nm.

Further, as the material of the conductive film 4, Pd, N
The sputtered film of i, Pt, and Au is replaced with the nitride thin film 6 of this embodiment.
When examined in combination with the above, almost the same results as described above were obtained.

[Embodiment 2] In this embodiment, the following method was used as the method of forming the nitride thin film 6 in the step-c after performing the steps -a and -b of the first embodiment. Step-c The above element was set in a vacuum film forming apparatus, and a SiN nitride thin film 6 was formed on the conductive film 4. SiN in this embodiment
The nitride thin film 6 is prepared by introducing monosilane and nitrogen by using a plasma CVD apparatus at a substrate temperature of 300 ° C.
The film was formed in 3.56 MHz RF plasma.

The thickness of the SiN nitride thin film 6 in this embodiment is 5
nm, and the sheet resistance was 7.4 × 10 ⁹ Ω / □.

The sheet resistance is determined by setting the gap L =
A comb-shaped electrode having a length of 5 μm and a length of W = 10 cm was formed, a SiN film was formed thereon under the same conditions, and the calculated value was calculated from a value of 3.7 × 10 ⁵ Ω measured by a tester. When a sample formed on a silicon substrate under the same conditions was subjected to surface analysis by XPS (X-ray photoelectron spectroscopy), the proportion of Si present as nitride ([silicon nitride] / [silicon nitride + silicon oxide]) Was 87%.

Steps -d and -e were performed in substantially the same manner as in Example 1. At this time, the forming power was 60 mW. Acetone was introduced into the vacuum device for the activation treatment, and the pressure was set to 1.3 × 10 ⁻² Pa.

The evaluation results were almost the same as in Example 1. For a device in which the thickness of the nitride thin film was changed in the range of 5 to 10 nm, and a device in which the material of the conductive film was changed, almost the same results as in Example 1 were obtained.

[Embodiment 3] In this embodiment, the following method was used as the method of forming the nitride thin film 6 in the step-c after performing the steps -a and -b of the first embodiment.

Step-c The above element was set in a vacuum film forming apparatus, and a W-GeN
A nitride thin film 6 was formed on the conductive film. In this embodiment
Nitride thin film W-GeN
W and Ge targets in a mixed atmosphere of argon and nitrogen
Was formed by sputtering. WG of this embodiment
The thickness of the eN nitride thin film is 5 nm, and the sheet resistance is 9.2 ×
10 ⁸ Ω / □.

The sheet resistance is obtained by setting the gap L =
A comb-shaped electrode having a length of 5 μm and a length of W = 10 cm was formed, a W-GeN film was formed thereon under the same conditions, and the calculated value was calculated from a value of 4.6 × 10 ⁴ Ω measured by a tester. The evaluation results were almost the same as in Example 1.

[Embodiment 4] In this embodiment, an image forming apparatus having a configuration shown in FIG. 10 using an electron source having a configuration shown in FIG. 9 in which a large number of electron-emitting devices of the present invention are arranged in a matrix is used. It was made.

FIG. 15 is a plan view of a part of the electron source.
FIG. 16 is a cross-sectional view taken along the line AA ′ in the figure.
Here, 1 is a substrate, 102 is an X-direction wiring (also called a lower wiring), 103 is a Y-direction wiring (also called an upper wiring), 2, 3
Is an element electrode, 4 is a conductive film, 6 is a nitride thin film, 401 is an interlayer insulating layer, and 402 is a contact hole for electrical connection between the element electrode 3 and the lower wiring 102. First, a method for manufacturing an electron source according to the present embodiment will be described with reference to FIGS. The following steps -a to i correspond to (a) to (e) of FIG. 17 and (f) to (i) of FIG.

Step-a On a substrate 1 in which a 0.5 μm thick silicon oxide film was formed on a cleaned blue plate glass by a sputtering method, 5 nm thick Cr and 600 nm thick Au were deposited by vacuum evaporation. After sequentially laminating, a photoresist (AZ1370: manufactured by Hoechst) was spin-coated with a spinner and baked.
The photomask image was exposed and developed to form a resist pattern of the lower wiring 102, and the Au / Cr deposited film was wet-etched to form the lower wiring 102 having a desired shape.

Step-b Next, an interlayer insulating layer 401 made of a silicon oxide film having a thickness of 1.0 μm was deposited by RF sputtering.

Step-c Contacting the silicon oxide film 401 deposited in the step-b
Photoresist pattern for forming hole 402
And etch the interlayer insulating layer 401 using this as a mask.
Contact hole 402 was formed. Etchin
Is CF_Four And H _Two RIE (Reactive) using gas
e Ion Etching) method.

Step-d Thereafter, the patterns of the device electrodes 2 and 3 are formed with a photoresist (RD-2000N-41: manufactured by Hitachi Chemical Co., Ltd.).
5 nm thick Ti, 100 nm thick by vacuum evaporation
Of Ni were sequentially deposited. The photoresist pattern was dissolved with an organic solvent, and the Ni / Ti deposited film was lifted off to form device electrodes 2 and 3.

Step-e After forming a photoresist pattern of the upper wiring 103 on the device electrodes 2 and 3, 5 nm thick Ti and 500 n thick
Au of m m was sequentially deposited by vacuum evaporation, and unnecessary portions were removed by lift-off to form an upper wiring 103 having a desired shape.

Step-f Next, a Cr film 403 having a thickness of 100 nm was deposited by vacuum evaporation, and was patterned by photolithography so as to have an opening in the shape of the conductive film 4 to form a mask. A solution of an organic Pd compound (ccp4230:
Okuno Pharmaceutical Co., Ltd.) by spinner, 30
Heating and baking treatment was performed at 0 ° C. for 10 minutes to form a conductive film 4 made of PdO fine particles. The thickness of this film is 10 nm
Met.

Step-g A W-GeN nitride thin film 6 was formed in the same manner as in Step-c of Example 3.

Step-h The Cr film 403 was wet-etched using an etchant to remove unnecessary portions of the conductive film 4 made of PdO fine particles and the unnecessary portion of the nitride thin film 6, and patterned into a desired shape. The resistance value was about Rs = 5 × 10 ⁴ Ω / □.

Step-i A resist pattern was formed except for the portion of the contact hole 402, and a Ti film having a thickness of 5 nm and a thickness of 500
nm of Au was sequentially deposited. Unnecessary portions were removed by lift-off to bury the contact holes 402. Through the above steps, the lower wiring 10 is formed on the substrate 1.
2, interlayer insulating layer 401, upper wiring 103, device electrode 2,
3. An unformed electron source on which a conductive film 4, a nitride thin film 6, etc. were formed was obtained.

Next, an image forming apparatus was manufactured by using the unformed electron source manufactured as described above. The manufacturing procedure will be described with reference to FIGS. After fixing the substrate 1 on the rear plate 111, a face plate 116 (formed by forming a fluorescent film 114 and a metal back 115 on the inner surface of a glass substrate 113) is placed 5 mm above the substrate 1 via a support frame 112. Then, frit glass was applied to a joint portion of the face plate 116, the support frame 112, and the rear plate 111, and sealed by baking at 430 ° C. for 10 minutes in the air. The fixing of the substrate 1 to the rear plate 111 was also performed using frit glass. The fluorescent film 114, which is an image forming member, is made of only a fluorescent substance in the case of monochrome, but in this embodiment, the fluorescent film 114 adopts a stripe shape (FIG. 11A), and a black stripe 121 is formed first. The fluorescent material 1 of each color is formed in the gap.
22 was applied to form a fluorescent film 114. As the material of the black stripe 122, a material mainly containing graphite, which is generally used, is used. A slurry method was used for applying the phosphor 122 to the glass substrate 113.

A metal back 115 is usually provided on the inner side of the fluorescent film 114. Metal back 115
After the formation of the fluorescent film 114, the inner surface of the fluorescent film 114 was subjected to a smoothing process (usually called filming), and then Al was vacuum-deposited.

The face plate 116 may be provided with a transparent electrode on the outer surface side of the fluorescent film 114 in order to further increase the conductivity of the fluorescent film 114.
A sufficient conductivity was obtained only with the metal back 115, so that the description was omitted. When the above-mentioned sealing is performed, in the case of color, the phosphors 122 of each color must correspond to the electron-emitting devices 104, so that sufficient alignment is performed.

The interior of the envelope 118 completed as described above is 1.3 × 1 through an exhaust device through an exhaust pipe (not shown).
When the pressure is reduced to about 0 ^-3 Pa, the external terminal D
A pulse voltage was applied between the device electrodes 2 and 3 of the electron-emitting device 104 through x1 to Dxm and Dy1 to Dyn, and a forming process was performed to form the electron-emitting portion 5. The waveform of the pulse used was a rectangular wave pulse having a gradually increasing peak value, a pulse width of 1 msec, and a pulse interval of 10 msec.
And During this process, the pressure in envelope 118 dropped further.

Next, n-hexane was introduced into the envelope 118, and the pressure was set to 1.3 × 10 ⁻³ Pa. It has the same pulse width and pulse interval as the forming process, and the peak value is 14
V square wave pulse applied, device current If, emission current Ie
The activation treatment was performed while measuring.

Next, while the entire envelope 118 was heated to 190 ° C., the evacuation was continued for 2 hours. Pressure is 1.3 × 10 ^-6 P
When the temperature decreased to a, the exhaust pipe was welded by heating with a gas burner, and the envelope 118 was sealed. Thereafter, in order to maintain the pressure in the envelope 118, a getter (not shown) in which the envelope 118 was previously installed was subjected to high-frequency heating to perform getter processing.

The display panel 201 completed as described above
(See FIG. 10), external terminals Dx1 to Dx
A scanning signal and a modulation signal are applied to the electron-emitting device 104 from a signal generating means (not shown) through m, Dy1 to Dyn, thereby emitting electrons, and a high voltage of about 10 kV is applied to the metal back 114 through the high-voltage terminal Hv. Then, an image was displayed by accelerating the electron beam, colliding with the fluorescent film 115, exciting and emitting light.

The image display device of this example was able to display a good image stably for a long time.

[Embodiment 5] FIG. 19 shows a display panel 201 (see FIG. 10) using the above-described surface conduction electron-emitting device as an electron source, for example, from various image information sources such as television broadcasting. FIG. 1 is a diagram illustrating an example of an image forming apparatus of the present invention configured to display provided image information.

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

When the present image forming apparatus receives a signal including both video information and audio information, such as a television signal, it naturally reproduces the audio simultaneously with the display of the video. Descriptions of circuits, speakers, and the like related to reception, separation, reproduction, processing, storage, and the like of audio information that are not directly related to the features of the present invention are omitted.

Hereinafter, the function of each section will be described along the flow of the image signal. First, the TV signal receiving circuit 1013 is a circuit for receiving a TV signal transmitted using a wireless transmission system such as radio waves or spatial optical communication. The type of the TV signal to be received is not particularly limited.
Any method such as the TSC method, the PAL method, and the SECAM method may be used. Further, a TV signal comprising a larger number of scanning lines than these, for example, a so-called high-definition TV including the MUSE system is a signal suitable for taking advantage of the display panel suitable for a large area and a large number of pixels. Source.

T received by TV signal receiving circuit 1013
The V signal is output to the decoder 1004. The TV signal receiving circuit 1012 is a circuit for receiving a TV signal transmitted using a wired transmission system such as a coaxial cable or an optical fiber. The TV signal receiving circuit 101
Similarly to 3, the type of the TV signal to be received is not particularly limited, and the TV signal received by the circuit 1012 is also output to the decoder 1004.

Image input interface circuit 1011
Is a circuit for taking in an image signal supplied from an image input device such as a TV camera or an image reading scanner.
Is output to

Image memory interface circuit 101
Reference numeral 0 denotes a circuit for capturing an image signal stored in a video tape recorder (hereinafter abbreviated as VTR). The captured image signal is output to a decoder 1004.

Image memory interface circuit 100
Reference numeral 9 denotes a circuit for capturing an image signal stored in the video disk.
004 is output.

Image memory interface circuit 100
Reference numeral 8 denotes a circuit for taking in an image signal from a device storing still image data, such as a still image disk. The taken still image data is input to the decoder 1004.

The input / output interface circuit 1005
A circuit for connecting the display device to an external computer, a computer network, or an output device such as a printer. In addition to inputting and outputting image data and character / graphic information, control signals and numerical data can be input and output between the CPU 1006 of the image forming apparatus and the outside in some cases. .

The image generation circuit 1007 is provided with image data, character / graphic information input from outside via the input / output interface circuit 1005, or the CPU 100.
6 is a circuit for generating display image data based on the image data and character / graphic information output from 6. Inside this circuit, for example, a rewritable memory for storing image data and character / graphic information, a read-only memory storing an image pattern corresponding to a character code, a processor for performing image processing, etc. And other circuits necessary for generating an image.

The display image data generated by the circuit 1007 is output to the decoder 1004, but may be output to an external computer network or printer via the input / output interface circuit 1005 in some cases. .

The CPU 1006 mainly performs operations related to operation control of the display device and generation, selection and editing of a display image. For example, a control signal is output to the multiplexer 1003, and image signals to be displayed on the display panel 201 are appropriately selected or combined. At that time, a control signal is generated to the display panel controller 1002 in accordance with the image signal to be displayed, and the display device controls the display device such as the screen display frequency, scanning method (for example, interlaced or non-interlaced), and the number of scanning lines on one screen. The operation is appropriately controlled. In addition, image data and character / graphic information are directly output to the image generation circuit 1007, or an external computer or memory is accessed via the input / output interface circuit 1005 to convert the image data or character / graphic information. input.

It should be noted that the CPU 1006 may be involved in work for other purposes. For example, it may directly relate to a function of generating and processing information, such as a personal computer or a word processor. Alternatively, as described above, the input / output interface circuit 10
The computer may be connected to an external computer network via the external computer 05 to perform operations such as numerical calculations in cooperation with external devices.

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

The decoder 1004 converts various image signals input from the above 1007 to 1013 into three primary color signals,
Alternatively, it is a circuit for inversely converting a luminance signal into an I signal and a Q signal. As shown by the dotted line in FIG.
004 preferably has an internal image memory. This is for handling a television signal that requires an image memory when performing inverse conversion, such as the MUSE method.

The provision of the image memory facilitates the display of a still image. Alternatively, the image generation circuit 1007
In addition, in cooperation with the CPU 1006, there is obtained an advantage that image processing and editing including image thinning, interpolation, enlargement, reduction, and synthesis become easy.

The multiplexer 1003 is provided for the CPU 1
A display image is appropriately selected based on a control signal input from 006. That is, the multiplexer 1003
Selects a desired image signal from the inversely converted image signals input from the decoder 1004 and selects a driving circuit 1001
Output to In that case, by switching and selecting an image signal within one screen display time, it is also possible to divide one screen into a plurality of areas and display different images depending on the areas, as in a so-called multi-screen television. .

Display panel controller 1002
Is a circuit for controlling the operation of the drive circuit 1001 based on a control signal input from the CPU 1006. The circuit 1002 outputs to the drive circuit 1001 a signal for controlling an operation sequence of a drive power supply (not shown) for the display panel 201, for example, as related to the basic operation of the display panel 201. As a method related to the driving method of the display panel 201, a signal for controlling, for example, a screen display frequency and a scanning method (for example, interlaced or non-interlaced) is output to the driving circuit 1001. In some cases, a control signal relating to image quality adjustment such as luminance, contrast, color tone, and sharpness of a display image may be output to the driving circuit 1001.

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

The function of each section has been described above. With the configuration illustrated in FIG. 19, in the present image forming apparatus, image information input from various image information sources can be displayed on the display panel 201. . That is, various image signals including television broadcasting are transmitted to the decoder 10.
After the inverse conversion in 04, the signal is appropriately selected in the multiplexer 1003 and input to the drive circuit 1001.
On the other hand, the display panel controller 1002 generates a control signal for controlling the operation of the drive circuit 1001 according to an image signal to be displayed. The driving circuit 1001
A drive signal is applied to the display panel 201 based on the image signal and the control signal. Thus, an image is displayed on the display panel 201. These series of operations are totally controlled by the CPU 1006.

In the present image forming apparatus, the image memory built in the decoder 1004, the image generation circuit 100
7 and information selected from the information, and for the displayed image information, for example, enlargement, reduction, rotation, movement, edge enhancement, thinning, interpolation, color conversion, image aspect ratio conversion, etc. It is also possible to perform image processing such as initial image processing and image editing such as combining, erasing, connecting, exchanging, and fitting. Although not specifically mentioned in the description of the present embodiment, a dedicated circuit for processing and editing audio information may be provided as in the above-described image processing and image editing.

Therefore, the present image forming apparatus can be used for a television broadcast display device, a video conference terminal device, an image editing device for handling still images and moving images, a computer terminal device, an office terminal device such as a word processor,
It is possible to combine functions such as game machines with one unit,
Extremely wide range of applications for industrial or consumer use.

FIG. 19 shows only an example of the configuration of an image forming apparatus using a display panel using a surface conduction electron-emitting device as an electron beam source. It goes without saying that the present invention is not limited to this.

For example, among the components shown in FIG. 19, circuits relating to functions that are not necessary for the purpose of use may be omitted.
Conversely, additional components may be added depending on the purpose of use. For example, when this display device is applied as a video phone, a TV camera, a voice microphone,
It is preferable to add an illuminator, a transmitting / receiving circuit including a modem, and the like to the components.

In the present image forming apparatus, since the surface conduction electron-emitting device is used as the electron source, the display panel can be easily made thin and the depth of the image forming apparatus can be reduced. In addition, a display panel using a surface conduction electron-emitting device as an electron beam source is easy to enlarge the screen, has high brightness, and has excellent viewing angle characteristics, so that the image forming apparatus is full of a sense of reality and has a powerful image. Can be displayed with good visibility.

[0202]

As described above, the electron-emitting device of the present invention can maintain good electron-emitting characteristics for a long time. In a large-area electron source in which a large number of electron-emitting devices are arrayed, the electron-emitting efficiency of each electron-emitting device can be improved. In an image forming apparatus using the above-mentioned electron source, high brightness and high contrast can be achieved. Is formed,
The image quality is greatly improved, and a stable image can be obtained for a long period of time.

As described above, according to the present invention, a large-area flat display which can handle a color image, has high luminance, high contrast, and has high display quality is realized.

[Brief description of the drawings]

FIG. 1 is a plan view and a cross-sectional view schematically showing a configuration of a flat-type electron-emitting device of the present invention.

FIG. 2 is a schematic diagram for explaining a state of covering a conductive film with a nitride thin film in the electron-emitting device of the present invention.

FIG. 3 is a cross-sectional view schematically showing a configuration of a vertical electron-emitting device of the present invention.

FIG. 4 is a diagram for explaining a method of manufacturing the surface conduction electron-emitting device of FIG.

FIG. 5 is a diagram illustrating an example of a voltage waveform used in the energization forming process.

FIG. 6 is a schematic diagram showing a schematic configuration of a device for evaluating characteristics of an electron-emitting device.

FIG. 7 is a diagram for explaining the relationship between the emission current Ie and the device current If and the device voltage Vf of the electron-emitting device of the present invention.

FIG. 8 is a schematic diagram showing a change over time in emission current Ie of the electron-emitting device of the present invention and the comparative electron-emitting device.

FIG. 9 is a schematic diagram showing a schematic configuration of an electron source of the present invention having a matrix wiring.

FIG. 10 is a schematic diagram showing a schematic configuration of a display panel used in the image forming apparatus of the present invention using an electron source of a matrix wiring.

FIG. 11 is a schematic diagram for explaining a shape of a fluorescent film in the display panel of the present invention.

12 is a diagram illustrating an example of a drive circuit that drives the display panel of FIG.

FIG. 13 is a plan view showing a schematic configuration of an electron source of the present invention having ladder-type wiring.

FIG. 14 is a schematic diagram showing a schematic configuration of a display panel used in an image forming apparatus of the present invention using an electron source having ladder-type wiring.

FIG. 15 is a partial plan view schematically showing a configuration of an electron source of a matrix wiring.

FIG. 16 is a schematic diagram showing a cross section along AA ′ of FIG.

17 is a schematic diagram for explaining a manufacturing process of the electron source in FIG.

FIG. 18 is a schematic diagram for explaining a manufacturing process of the electron source in FIG.

FIG. 19 is a block diagram illustrating an example of a configuration of an image forming apparatus.

[Explanation of symbols]

1: substrate, 2, 3 element electrodes, 4: conductive film, 5: electron emitting portion, 6: nitride thin film, 21: step forming member, 50: ammeter, 51: power supply, 52: ammeter, 53: High voltage power supply, 5
4: anode electrode, 55: vacuum device, 56: exhaust pump, 102: X-direction wiring (lower wiring), 103: Y-direction wiring (upper wiring), 104: electron-emitting device, 105: connection,
111: rear plate, 112: support frame, 113: glass substrate, 114: fluorescent film, 115: metal back, 11
6: face plate, 118: envelope, 121: black conductive material, 122: phosphor, 201: display panel, 20
2: scanning circuit, 203: control circuit, 204: shift register, 205: line memory, 206: synchronization signal separation circuit, 207: modulation signal generator, 211: polypropylene frame, 212: water supply pipe, 213: suction for surface cleaning Nozzle, 214: vertical moving arm, 215: substrate, 216: barrier, 217: movable wall, 218: roller, 219: pulley, 220: weight, 301: display panel, 302: grid electrode, 303: opening, 304: common Wiring, 40
1: interlayer insulating layer, 402: contact hole, 403:
Cr film, 1001: drive circuit, 1002: display controller, 1003: multiplexer, 1004:
Decoder, 1005: input / output interface circuit, 1
006: CPU, 1007: Image generation circuit, 1008:
Image memory interface circuit, 1009: Image memory interface circuit, 1010: Image memory interface circuit, 1011: Image input interface circuit, 1012: TV signal receiving circuit, 1013:
TV signal receiving circuit, 1014: input unit.

Claims (12)

[Claims] A pair of opposing element electrodes formed on a base, a conductive thin film formed in electrical communication with the element electrodes, and a gap formed in a part of the conductive thin film. , Wherein at least a part of the conductive thin film is covered with a nitride. 2. The electron-emitting device according to claim 1, further comprising a deposited layer made of carbon, a carbon compound, or a mixture of both, on the conductive thin film. 3. The method according to claim 2, wherein the nitride is B, Al, C, Si, G
3. A nitride of at least one kind of metal or metalloid element selected from the group consisting of e, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and W. An electron-emitting device according to claim 1. 4. The conductive thin film according to claim 1, wherein the nitride is contained in the conductive thin film at a molar ratio of the metal or metalloid element of 10 to 50% to the whole of the conductive thin film and the nitride. The electron-emitting device according to claim 3, wherein: 5. The electron-emitting device according to claim 1, wherein the nitride forms a nitride thin film layer having a thickness of 3 nm or more and 10 nm or less on the conductive thin film. . 6. An electron source, wherein a plurality of the electron-emitting devices according to claim 1 are arranged on a substrate. 7. An image forming apparatus comprising the electron source and the image forming member according to claim 6 in a vacuum container. 8. A method for manufacturing an electron-emitting device according to claim 1, comprising a step of coating at least a conductive thin film with a nitride thin film, and a forming step. Of manufacturing an electron-emitting device. 9. The method according to claim 8, further comprising, after the forming step, performing an activation step of forming a deposited layer made of carbon, a carbon compound, or a mixture of both. 10. The method according to claim 8, wherein the step of covering the conductive thin film with a nitride thin film is performed before the forming step. 11. A method for manufacturing an electron source according to claim 6, wherein the method for manufacturing an electron-emitting device according to claim 8 is applied. Method. 12. A method for manufacturing an image forming apparatus according to claim 7, wherein the method for manufacturing an electron source according to claim 11 is applied.