JP2000243248A - Electron emission element, electron source, image forming device and manufacture of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce impairing in driving and to obtain stable characteristic by executing the antioxidizing treatment to carbon accumulated by activating treatment, on an electron emission portion of a conductive film formed over a pair of element electrodes mounted on a base. SOLUTION: Element electrodes 2, 3 are formed on a cleaned base 1, for example, by photolithographic technique, and an organic metallic solution is applied thereto to form an organic metal thin film. Then the thermal baking treatment and the patterning by lift-off, etching and the like are executed to form a conductive film 4. The power is supplied between the element electrodes 2, 3 to partially form an area having a structural change by breaking, deforming, denaturing and the like, on the conductive film 4. The pulse waveform is applied by raising the temperature. Then the activating treatment is executed by repeating the application of a pulse. Carbon or a carbon compound from an organic substance existing in the atmosphere is accumulated on the elements by this treatment. The accumulated carbon is treated by a halogen compound, a phosphorus compound or boron as the antioxidizing treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Conventionally, two types of electron-emitting devices are known, namely, a thermionic electron-emitting device and a cold cathode electron-emitting device. Field emission type (hereinafter, referred to as "FE")
Type ". ), Metal / insulating layer / metal type (hereinafter referred to as “MI
M type ". ) And surface conduction electron-emitting devices.

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

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

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

[0006] The surface conduction electron-emitting device utilizes a phenomenon in which electrons are emitted by passing a current through a small-area thin film formed on an insulating 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
Films ", 9, 317 (1972)], In ₂
O ₃ / SnO ₂ thin film [M. Hartwell
and C.I. G. FIG. Fonstad: "IEEE T
rans. ED Conf. ", 519 (197
5)], using a carbon thin film [Hisashi Araki et al .: Vacuum,
26, No. 1, p. 22 (1983)].

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

In these surface conduction electron-emitting devices, it is general that the electron-emitting portion 5 is formed beforehand by performing an energization process called energization forming on the conductive film 4 before electron emission. That is, the energization forming means that a voltage is applied to both ends of the conductive film 4, and the conductive film 4 is locally destroyed, deformed or deteriorated to change the structure, and the electrons in an electrically high-resistance state are formed. This is a process for forming the emission unit 5. Note that a crack is generated in a part of the conductive film 4 in the electron emitting portion 5, and electrons are emitted from the vicinity of the crack.

The above-mentioned surface conduction electron-emitting device has an advantage that a large number of devices can be arrayed over a large area because of its simple structure. Therefore, various applications for utilizing this feature are being studied. For example, a charged beam source,
Application to an image forming apparatus such as a display device is exemplified.

Conventionally, as an example in which a large number of surface conduction electron-emitting devices are arrayed, surface conduction electron-emitting devices are arranged in parallel, and both ends (both device electrodes) of each surface conduction electron-emitting device are wired. (Also referred to as a common wiring). An electron source in which rows each connected by a common line (also referred to as a ladder-type arrangement) are provided (for example, JP-A-64-31332, JP-A-1-283737, 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 self-luminous display device that does not require a backlight is used as a surface conduction type electron emission device. There has been proposed a display device in which an electron source in which a number of elements are arranged and a phosphor that emits visible light when irradiated with an electron beam from the electron source are combined (US Pat. No. 5,066,883).

[0012]

There are various problems in putting this surface conduction type electron-emitting device into practical use. However, the stability and controllability of the device characteristics are improved, and the efficiency (voltage applied to the device electrode) is increased. In order to increase the ratio of the current Ie discharged into the vacuum (hereinafter, referred to as “emission current Ie”) to the current If (hereinafter, referred to as “element current If”) flowing when is applied, Among the electron-emitting devices having a conductive film including a high-resistance portion by an activation process, an electron-emitting device in which a deposit mainly composed of carbon is formed in the high-resistance portion has been reported (Japanese Patent Application Laid-Open No. 7-235255). Gazette).

However, when an electron-emitting device in which a deposit containing carbon as a main component is formed in a high-resistance portion of a conductive film is driven in a vacuum to emit electrons, the amount of electron emission gradually increases with driving time. In some cases, the phenomenon of reduction, that is, the phenomenon of deterioration of the electron-emitting device occurs.

Such deterioration in characteristics is a serious problem, for example, when an electron-emitting device is applied to an image forming apparatus, because it directly leads to a reduction in luminance.

In view of the above problems, it is an object of the present invention to provide a novel structure of an electron-emitting device which exhibits little drive deterioration and stable characteristics, an electron source using the same, an image forming apparatus, and a method of manufacturing the same. To provide.

[0016]

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

That is, the first aspect of the present invention is to provide an electron-emitting device having an electron-emitting portion in a conductive film extending between a pair of device electrodes provided on a substrate, wherein the electron-emitting portion is deposited on the electron-emitting portion by an activation process. An electron emission element is characterized in that the carbon subjected to the oxidation treatment is subjected to oxidation resistance.

According to a second aspect of the present invention, there is provided a method for manufacturing the above-mentioned first electron-emitting device according to the present invention, wherein a step of forming a pair of element electrodes on a substrate and a step of forming a conductive layer extending between the element electrodes are performed. A step of forming a film, a step of applying an electric current between the device electrodes to form an electron-emitting portion in the conductive film, an activation step of depositing carbon in the electron-emitting portion, and a step of applying carbon to the electron-emitting portion. Performing an oxidation-resistant treatment by using an electron-emitting device.

A third aspect of the present invention is an electron source which emits electrons in response to an input signal, wherein a plurality of the first electron-emitting devices of the present invention are arranged on a substrate. In the electron source.

A fourth aspect of the present invention is a method of manufacturing the third electron source of the present invention, wherein a plurality of electron-emitting devices are manufactured by the second method of the present invention. In a method of manufacturing an electron source.

According to a fifth aspect of the present invention, there is provided an apparatus for forming an image based on an input signal, comprising at least the third electron source of the present invention and irradiation of an electron beam emitted from the electron source. And an image forming member for forming an image by using the image forming apparatus.

A sixth aspect of the present invention is a method of manufacturing the fifth image forming apparatus of the present invention, wherein the electron source is manufactured by the fourth method of the present invention. A method for manufacturing a forming apparatus.

According to the present invention, the carbon deposited on the electron-emitting portion formed by the forming process on the conductive film is subjected to the oxidation-resistant process. Various methods can be applied as the oxidation resistance treatment, and the effect is particularly large when treatment with a halogen compound, treatment with a phosphorus compound, or treatment with a boron compound is applied.

[0024]

Next, preferred embodiments of the present invention will be described.

FIG. 1 is a schematic view showing an example of the configuration of an electron-emitting device according to the present invention. FIG. 1 (a) is a plan view and FIG.
Is a longitudinal sectional view. In FIG. 1, 1 is a substrate, 2 and 3 are electrodes (element electrodes), 4 is a conductive film, 5 is an electron-emitting portion, 6
Is carbon that has been subjected to oxidation resistance treatment.

Examples of the substrate 1 include quartz glass, glass having a reduced content of impurities such as Na, blue plate glass, a laminate of blue plate glass with SiO ₂ laminated by sputtering, 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, for example, Ni, C
metals or alloys such as r, Au, Mo, W, Pt, Ti, Al, Cu, Pd and Pd, Ag, Au, RuO ₂ , Pd
Metal or metal oxide and printed conductor composed of glass or the like, such as -ag, is appropriately selected from a semiconductor conductive materials such as transparent conductor and polysilicon or the like In ₂ O ₃ -SnO _2.

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

In addition to the structure shown in FIG. 1, a structure in which a conductive film 4 and device electrodes 2 and 3 are formed on a substrate 1 in this order may be adopted. Further, depending on the manufacturing method, the entire space between the opposing element electrodes 2 and 3 may function as an electron emitting portion.

Examples of the material constituting the conductive film 4 include Pd, Pt, Ru, Ag, Au, Ti, In, Cu,
Metals such as Cr, Fe, Zn, Sn, Ta, W, and Pb;
_{dO, SnO 2, In 2 O} 3, PbO, oxide conductor, such as _{Sb 2 O 3, HfB 2,} ZrB 2, LaB 6, CeB
₆ , borides such as YB ₄ and GdB ₄ , TiC, ZrC, H
carbides such as fC, TaC, SiC, WC, TiN, Zr
Examples include nitrides such as N and HfN, semiconductors such as Si and Ge, and carbon.

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 between the device electrodes 2 and 3, and the like. nm, more preferably 1 nm to 50 n
m. The resistance value of Rs is 10 ²
The value is preferably from Ω / □ to 10 ⁷ Ω / □. Note that Rs is a value that appears when a resistance R measured in the length direction of a thin film having a width w and a length 1 is set as R = Rs (l / w).

The electron-emitting portion 5 is constituted by a high-resistance crack formed in a part of the conductive film 4 and contains therein conductive fine particles having a particle size ranging from several Å to several tens nm. In some cases. The conductive fine particles contain some or all of the elements of the material constituting the conductive film 4. Further, the electron-emitting portion 5 and the conductive film 4 in the vicinity thereof may have carbon or a carbon compound formed by an activation step described later.

There are various methods for manufacturing the electron-emitting device of the present invention. One example will be described with reference to FIG. In FIG. 2, the same parts as those shown in FIG. 1 are denoted by the same reference numerals as those shown in FIG.

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. 2A).

2) On the substrate 1 provided with the device electrodes 2 and 3,
An organometallic solution is applied to form an organometallic film. As the organic metal solution, a solution of an organic compound containing the above-described metal of the conductive film as a main element can be used. The organic metal film is heated and baked, and is patterned by lift-off, etching, or the like to form a conductive film 4.
(B)). 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 deposition method, a sputtering method, a chemical vapor deposition method,
A dispersion coating method, a dipping method, a spinner method, or the like can also be used.

3) Next, an energization process called forming is performed. When current is applied between the device electrodes 2 and 3, the electron-emitting portion 5 is formed at the portion of the conductive film 4 (FIG. 2C).

In the forming step, heat energy is locally concentrated on a part of the conductive film 4 instantaneously, and an electron emitting portion 5 having a changed structure is formed at that portion.

FIG. 3 shows an example of the voltage waveform of the energization forming.

The voltage waveform is particularly preferably a pulse waveform.
The method shown in FIG. 3A in which a pulse with a constant pulse crest value is applied continuously and the method shown in FIG. 3B in which a pulse is applied while increasing the pulse crest value are used for this purpose. is there.

First, the case where the pulse peak value is a constant voltage will be described with reference to FIG. T ₁ in FIG.
And T ₂ are the pulse width and the pulse interval of the voltage waveform. The peak value (peak voltage) of the triangular wave is appropriately selected according to the form of the electron-emitting device. Under such conditions, for example, a voltage is applied for several seconds to several tens minutes. The pulse waveform is
The waveform is not limited to the triangular wave, and a desired waveform such as a rectangular wave can be adopted.

Next, a case where a voltage pulse is applied while increasing the pulse peak value will be described with reference to FIG.
T ₁ and T ₂ in FIG. 3B can be the same as those shown in FIG. 3A. The peak value (peak voltage) of the triangular wave can be increased, for example, in steps of about 0.1 V.

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

The electrical processing after the forming processing can be performed in a vacuum processing apparatus as shown in FIG. 4, for example. This vacuum processing device also has a function as a measurement evaluation device. 4, the same parts as those shown in FIG. 1 are denoted by the same reference numerals as those shown in FIG.

In FIG. 4, reference numeral 55 denotes a vacuum vessel,
Reference numeral 6 denotes an exhaust pump. An electron-emitting device is provided in the vacuum vessel 55. Reference numeral 51 denotes a power supply for applying a device voltage Vf to the electron-emitting device, 50 denotes an ammeter for measuring a device current If flowing between the device electrodes 2 and 3, and 54 denotes a device emitted from the electron-emitting portion 5 of the device. An anode electrode 53 for capturing the emission current Ie, a high-voltage power supply 53 for applying a voltage to the anode electrode 54, and an ammeter 52 for measuring the emission current Ie emitted from the electron emission section 5. As an example, the voltage of the anode electrode 54 is 1 kV to 1 kV.
The measurement can be performed with the range of 0 kV and the distance H between the anode electrode 54 and the electron-emitting device in the range of 2 mm to 8 mm.

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

The exhaust pump 56 is composed of a normal high vacuum system such as a turbo pump and a rotary pump, and an ultra high vacuum system such as an ion pump. The entire vacuum processing apparatus provided with the electron-emitting device substrate shown here can be heated by a heater (not shown).

4) Next, a process called an activation step is performed on the element after the forming.

The activation step can be performed, for example, by repeatedly applying a pulse between the device electrodes 2 and 3 in an atmosphere containing an organic substance gas in the same manner as in energization forming. Device current If, emission current Ie
Changes significantly.

The atmosphere containing the organic substance gas in the activation step is formed by utilizing the 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. Alternatively, it can be obtained by introducing a gas of an appropriate organic substance into a vacuum once sufficiently evacuated by an ion pump or the like that does not use oil. The preferable gas pressure of the organic substance at this time varies depending on the form of the above-described element, the shape of the vacuum vessel, the type of the organic substance, and the like, and is appropriately set according to the case. Suitable organic substances include aliphatic hydrocarbons of alkanes, alkenes, and alkynes, aromatic hydrocarbons, alcohols, aldehydes, ketones, amines, and organic acids such as phenols, carboxylic acids, and sulfonic acids. And specifically, C, methane, ethane, propane, etc.
saturated hydrocarbons represented by _n H _{2n + 2} , unsaturated hydrocarbons 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 can be used.

By this treatment, carbon or a carbon compound is deposited on the device from organic substances existing in the atmosphere,
The element current If and the emission current Ie change remarkably. In FIG. 1, reference numeral 6 denotes carbon deposited in the activation step.

The carbon or carbon compound includes, for example, graphite (so-called HOPG, PG, GC), and HOPG has an almost perfect graphite crystal structure, P
G indicates that the crystal grain is about 20 nm and the crystal structure is slightly disordered, and GC indicates that the crystal grain is about 2 nm and the disorder of the crystal structure is further increased. ), Amorphous carbon (refers to amorphous carbon and a mixture of amorphous carbon and the microcrystals of graphite);
Also included are those in which carbon at the surface and grain boundaries partially forms a bond with another element such as hydrogen or nitrogen.
The film thickness is preferably in the range of 50 nm or less,
More preferably, the thickness is 30 nm or less.

The end of the activation step can be determined as appropriate while measuring the device current If and the emission current Ie.

The carbon deposited in the activation step is subjected to an oxidation resistance treatment. As oxidation resistance treatment,
Among many experiments performed by the present inventors, treatment with a halogen compound, treatment with a phosphorus compound, and treatment with a boron compound were particularly effective. Examples of the method of treatment with these compounds include a method in which each compound is dripped in a small amount on the device, a method in which the compound is exposed to a high-concentration vapor of the compound, and the like. Thereafter, if necessary, a step (for example, heating or the like) of removing an excess compound used in the above treatment is performed.

The electron-emitting device thus prepared was introduced into a vacuum processing apparatus, and the electron-emitting behavior was observed. The vacuum vessel and measurement system of the evaluation device that observes the electron emission behavior are:
This is a vacuum processing apparatus similar to that in which the forming process and the activation process are performed.

When the electron-emitting device of the present invention in which the deposited carbon was subjected to the oxidation-resistant treatment and the electron-emitting device which was not subjected to the oxidation-resistant treatment after the activation were simultaneously driven in a vacuum processing apparatus, both were activated. In both cases, it was observed that the device current and the emission current decreased with driving, but the electron-emitting device of the present invention subjected to the oxidation-resistant treatment was compared with the electron-emitting device not subjected to the oxidation-resistant treatment. Device current I with driving time
It was confirmed that the rate of decrease of f and the emission current Ie was small, and that the oxidation-resistant treatment of the present invention made it possible to manufacture an electron-emitting device having excellent durability.

When an electron-emitting device in which carbon is deposited on an electron-emitting portion to which the present invention can be applied is driven in a vacuum and changes in the device current If and the emission current Ie are observed, generally,
It is observed that these currents decrease with time.

Although the cause of the deterioration of the device has not been completely elucidated yet, from the results of detailed investigations by the present inventors, it has been found that oxidizing substances such as O ₂ and H ₂ O contained in a vacuum atmosphere are oxidized. It is considered that the partial elimination of carbon due to gas oxidation is one of the causes.

On the other hand, a great deal of research has been conducted on the prevention of carbon oxidation, and roughly classified into a method of covering the entire carbon with a substance having low oxygen permeability and a method of adding various chemical species to active carbon sites. There are two ways to prevent the reaction with oxygen by bonding. In the latter, sites such as edges and defects of the graphite sheet where the carbon oxidation reaction is likely to occur are poisoned by previously binding elements such as halogens, thereby preventing an attack by oxygen. As for this method, the present inventors have conducted many studies on an electron-emitting device on which carbon is deposited, and as a result, a halogen compound such as a chlorine-containing organic compound, a phosphorus compound such as a phosphoric acid ester, and a boric acid ester are used. It has been found that treatment with such a boron compound is particularly effective.

According to the present invention, the carbon deposited on the electron-emitting portion is subjected to an oxidation-resistant treatment with a halogen compound, a phosphorus compound, and a boron compound, so that O ₂ and H ₂ O contained in a vacuum are removed. This prevents the oxidation of carbon by the oxidizing gas, thereby improving the durability of the electron-emitting device.

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

FIG. 5 is a diagram schematically showing the relationship between the emission current Ie and the device current If measured by using the vacuum processing apparatus shown in FIG. 4, and the device voltage Vf. In FIG. 5, 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. 5, the electron-emitting device of the present invention has the following three characteristic characteristics with respect to the emission current Ie.

First, the emission current Ie of the present device rapidly increases when an element voltage higher than a certain voltage (referred to as a threshold voltage; Vth in FIG. 5) is applied, whereas when the element voltage is lower than the threshold voltage Vth, the emission current Ie is increased. Ie is hardly detected. That is, it is a non-linear element having a clear threshold voltage Vth with respect to the emission current Ie.

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

Third, the emission charge captured by the anode electrode 54 (see FIG. 4) depends on the time during which the device voltage Vf is applied. That is, the amount of charge captured by the anode electrode 54 can be controlled by the time during which the device voltage Vf is applied.

As understood from the above description, the electron-emitting device of the present invention can easily control the electron-emitting characteristics according to the input signal. By utilizing this property, it is possible to apply to various fields such as an electron source and an image forming apparatus having a plurality of electron-emitting devices.

FIG. 5 shows an example in which the element current If monotonically increases with respect to the element voltage Vf (MI characteristic).
The element current If may exhibit a voltage-controlled negative resistance characteristic (VCNR characteristic) with respect to the element voltage Vf (not shown).
These properties can be controlled by controlling the steps described above.

Next, application examples of the electron-emitting device of the present invention will be described below. By arranging a plurality of electron-emitting devices of the present invention on a substrate, for example, an electron source or an image forming apparatus can be configured.

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

The electron-emitting device of the present invention has three characteristics as described above. That is, the emission electrons from the surface conduction electron-emitting device can be controlled by the peak value and the width of the pulse-like voltage applied between the opposing device electrodes when the electrons are equal to or higher than the threshold voltage. On the other hand, below the threshold voltage, almost no emission occurs. According to this characteristic, even when a large number of electron-emitting devices are arranged, if a pulse-like voltage is appropriately applied to each device,
The electron emission amount can be controlled by selecting the surface conduction electron-emitting device according to the input signal.

Hereinafter, based on this principle, an electron source substrate obtained by arranging a plurality of electron-emitting devices of the present invention will be described with reference to FIG. 6, reference numeral 71 denotes an electron source substrate;
Reference numeral 2 denotes an X-direction wiring, and 73 denotes a Y-direction wiring. 74 is an electron-emitting device, and 75 is a connection.

The m X-direction wirings 72 are Dx1, Dx
2,..., Dxm, and can be formed of a conductive metal or the like formed using a vacuum deposition method, a printing method, a sputtering method, or the like. The material, thickness and width of the wiring are appropriately designed.
The Y-directional wiring 73 includes n wirings Dy1, Dy2,..., Dyn, and is formed in the same manner as the X-directional wiring 72. An interlayer insulating layer (not shown) is provided between the m X-directional wirings 72 and the n Y-directional wirings 73 to electrically separate them (m and n are both Positive integer).

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

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

The material forming the wiring 72 and the wiring 73, the material forming the connection 75, and the material forming the pair of element electrodes may have some or all of the same or different constituent elements. Good. These materials are appropriately selected, for example, from the above-described materials for the device electrodes. When the material forming the element electrode is the same as the wiring material, the wiring connected to the element electrode can also be called an element electrode.

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

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

An image forming apparatus constructed using such an electron source having a simple matrix arrangement will be described with reference to FIGS. 7, 8 and 9. FIG. 7 is a schematic diagram illustrating an example of a display panel of the image forming apparatus, and FIG. 8 is a schematic diagram of a fluorescent film used in the image forming apparatus of FIG. FIG.
FIG. 2 is a block diagram illustrating an example of a drive circuit for performing display in accordance with a TSC television signal.

In FIG. 7, reference numeral 71 denotes an electron source substrate on which a plurality of electron-emitting devices are arranged; 81, a rear plate on which the electron source substrate 71 is fixed; 86, a fluorescent film 84 on the inner surface of a glass substrate 83;
And a face plate on which a metal back 85 and the like are formed. Reference numeral 82 denotes a support frame, and a rear plate 81 and a face plate 86 are connected to the support frame 82 using frit glass or the like. Reference numeral 88 denotes an envelope, which is sealed by firing at a temperature range of 400 to 500 ° C. for 10 minutes or more in the atmosphere or nitrogen, for example.

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

The envelope 88 includes the face plate 86, the support frame 82, and the rear plate 81 as described above. Since the rear plate 81 is provided mainly for the purpose of reinforcing the strength of the substrate 71, if the substrate 71 itself has sufficient strength, the separate rear plate 81 can be unnecessary. That is, the support frame 82 is directly sealed to the substrate 71, and the envelope 8 is formed by the face plate 86, the support frame 82 and the substrate 71.
8 may be configured. On the other hand, by providing a support (not shown) called a spacer between the face plate 86 and the rear plate 81, the envelope 88 having sufficient strength against atmospheric pressure can be configured.

FIG. 8 is a schematic diagram showing a fluorescent film. The fluorescent film 84 can be composed of only a phosphor in the case of monochrome. In the case of a color fluorescent film, it may be composed of a black conductive material 91 called a black stripe (FIG. 8A) or a black matrix (FIG. 8B) and a fluorescent material 92 depending on the arrangement of the fluorescent materials. it can. The purpose of providing a black stripe and black matrix is
In the case of color display, the color separation between the phosphors 92 of the necessary three primary color phosphors is made black so that color mixing and the like become inconspicuous, and the reduction in contrast due to reflection of external light on the phosphor film 84 is suppressed. It is in. Black conductive material 91
As the material of, other than a commonly used material containing graphite as a main component, a material having conductivity and low light transmission and reflection can be used.

As a method of applying the phosphor on the glass substrate 83, a precipitation method or a printing method can be adopted regardless of monochrome or color. Usually, a metal back 85 is provided on the inner surface side of the fluorescent film 84. The purpose of providing a metal back is
The light emitted from the phosphor toward the inner surface is converted into a face plate 8.
Improving the brightness by specular reflection on the 6 side,
The purpose is to function as an electrode for applying an electron beam acceleration voltage, and to protect the phosphor from damage due to collision of negative ions generated in the envelope. The metal back can be manufactured by performing a smoothing process (usually called “filming”) on the inner surface of the fluorescent film after manufacturing the fluorescent film, and then depositing Al using vacuum evaporation or the like.

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

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

The image forming apparatus shown in FIG. 7 is manufactured, for example, as follows.

[0087] in the envelope 88 is evacuated from a suitable heating Shinano, ion pump, through an exhaust pipe (not shown) by an exhaust device not using oil, such as a sorption pump, ^10-5
After the atmosphere is made sufficiently low in the organic substance with a degree of vacuum of about Pa, sealing is performed. In order to maintain a vacuum degree after the envelope 88 is sealed, a getter process may be performed. This is, immediately before or after sealing the envelope 88,
This is a process of heating a getter (not shown) arranged at a predetermined position in the envelope 88 by heating using resistance heating, high-frequency heating, or the like to form a vapor deposition film. The getter usually contains Ba or the like as a main component, and maintains a degree of vacuum of, for example, 1 × 10 ⁻⁵ Pa or more by the adsorption action of the deposited film. Here, steps after the forming process of the electron-emitting device can be set as appropriate.

Next, an example of the configuration of a drive circuit for performing television display based on NTSC television signals on a display panel configured using electron sources in a simple matrix arrangement will be described with reference to FIG. . In FIG. 9, 10
1 is an image display panel, 102 is a scanning circuit, 103 is a control circuit, 104 is a shift register, 105 is a line memory, 106 is a synchronization signal separation circuit, 107 is a modulation signal generator, and Vx and Va are DC voltage sources.

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

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

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

The control circuit 103 has a function of matching the operation of each section so that an appropriate display is performed based on an image signal input from the outside. The control circuit 103 controls the synchronization signal Tsync sent from the synchronization signal separation circuit 106.
, Tscan, Tsft and T
mry control signals are generated.

The synchronizing signal separating circuit 106 is a circuit for separating a synchronizing signal component and a luminance signal component from an NTSC television signal input from the outside, and uses a general frequency separating (filter) circuit or the like. Can be configured. The synchronizing signal separated by the synchronizing signal separating circuit 106 includes a vertical synchronizing signal and a horizontal synchronizing signal, but is shown here as a Tsync signal for convenience of explanation. The luminance signal component of the image separated from the television signal is represented as a DATA signal for convenience. This DATA signal is output to the shift register 10
4 is input.

The shift register 104 is for serially / parallel converting the DATA signal input serially in time series for each line of an image, and is based on a control signal Tsft sent from the control circuit 103. (In other words, the control signal Tsft may be rephrased as a shift clock of the shift register 104). Data for one line of serial / parallel converted image (equivalent to drive data for n electron-emitting devices)
Are output from the shift register 104 as n parallel signals of Id1 to Idn.

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

The modulation signal generator 107 outputs the image data I
A signal source for appropriately driving and modulating each of the electron-emitting devices in accordance with each of d'1 to Id'n, and an output signal thereof is supplied to the display panel 1 through terminals Doy1 to Doyn.
01 is applied to the electron-emitting device.

As described above, the electron-emitting device of the present invention has the following basic characteristics with respect to the emission current Ie. That is, electron emission has a clear threshold voltage Vth, and Vth
Electron emission occurs only when the above voltage is applied. For a voltage equal to or higher than the electron emission threshold, the emission current also changes according to the change in the voltage applied to the device. From this, when a pulse-like voltage is applied to this element, for example, when a voltage lower than the electron emission threshold voltage is applied, electron emission does not occur, but when a voltage higher than the electron emission threshold voltage is applied, electrons are not emitted. A beam is output. At that time, the intensity of the output electron beam can be controlled by changing the peak value Vm of the pulse. Further, by changing the pulse width Pw, it is possible to control the total amount of charges of the output electron beam.

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

The shift register 104 and the line memory 10
5 can be a digital signal type or an analog signal type. This is because the serial / parallel conversion and storage of the image signal may be performed at a predetermined speed.

When the digital signal type is used, it is necessary to convert the output signal DATA of the synchronization signal separation circuit 106 into a digital signal. For this purpose, an A / D converter is provided at the output of the synchronization signal separation circuit 106. Just do it. In this connection, the circuit used for the modulation signal generator 107 is slightly different depending on whether the output signal of the line memory 105 is a digital signal or an analog signal. That is, in the case of the voltage modulation method using a digital signal, the modulation signal generator 107 includes:
For example, a D / A conversion circuit is used, and an amplification circuit and the like are added as necessary. In the case of the pulse width modulation method, the modulation signal generator 107 includes, for example, a high-speed oscillator, a counter 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.

In the case of the voltage modulation method using an analog signal, an amplification circuit using, for example, an operational amplifier or the like can be used as the modulation signal generator 107, and a level shift circuit or the like can be added as necessary. In the case of the pulse width modulation method, for example, a voltage controlled oscillator (VCO) can be employed, and an amplifier for amplifying the voltage up to the driving voltage of the electron-emitting device can be added as necessary.

In the image forming apparatus of the present invention which can have such a configuration, each of the electron-emitting devices is provided with an external terminal Do.
By applying a voltage via x1 to Doxm and Doy1 to Doyn, electron emission occurs. High voltage terminal 8
A high voltage is applied to the metal back 85 or the transparent electrode (not shown) via the, and the electron beam is accelerated. The accelerated electrons collide with the fluorescent film 84 and emit light to form an image.

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

Next, the above-described ladder-type arrangement of electron sources and the image forming apparatus will be described with reference to FIGS. 10 and 11. FIG.

FIG. 10 is a schematic diagram showing an example of a ladder type electron source. In FIG. 10, reference numeral 110 denotes an electron source substrate, and 111 denotes an electron-emitting device. 112 denotes common wirings Dx1 to Dx10 for connecting the electron-emitting devices 111.
These are drawn out as external terminals. A plurality of electron-emitting devices 111 are arranged on the substrate 110 in parallel in the X direction (this is called an element row). A plurality of the element rows are arranged to constitute an electron source. By applying a drive voltage between the common wires of each element row, each element row can be driven independently. That is, a voltage equal to or higher than the electron emission threshold is applied to an element row in which an electron beam is to be emitted, and a voltage equal to or lower than the electron emission threshold is applied to an element row in which an electron beam is not desired to be emitted. The common wirings Dx2 to Dx9 located between the element rows are, for example, Dx2 and Dx3,
Dx4 and Dx5, Dx6 and Dx7, and Dx8 and Dx9 may be formed as one and the same wiring.

FIG. 11 is a schematic diagram showing an example of a panel structure in an image forming apparatus having a ladder-type electron source. Reference numeral 120 denotes a grid electrode, 121 denotes an opening through which electrons pass, Dox1 to Doxm denote external terminals, and G1 to Gn denote external terminals connected to the grid electrode 120. Reference numeral 110 denotes an electron source substrate in which the common wiring between each element row is the same wiring. In FIG. 11, the same portions as those shown in FIGS. 7 and 10 are denoted by the same reference numerals as those shown in these drawings. An image forming apparatus shown here;
The major difference from the image forming apparatus having the simple matrix arrangement shown in FIG.
Between the grid electrodes 120.

In FIG. 11, a grid electrode 120 is provided between the substrate 110 and the face plate 86. The grid electrode 120 is for modulating the electron beam emitted from the electron-emitting device 111,
In order to allow an electron beam to pass through stripe-shaped electrodes provided orthogonally to the ladder-type element rows, one circular opening 121 is provided for each element. The shape and arrangement position of the grid electrodes are not limited to those shown in FIG. For example, a large number of passage openings can be provided in a mesh shape as openings, and a grid electrode can be provided around or near the electron-emitting device.

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

In the image forming apparatus of this embodiment, a modulation signal for one line of an image is simultaneously applied to the grid electrode rows in synchronization with sequentially driving (scanning) the element rows one by one. This makes it possible to control the irradiation of each electron beam to the phosphor and display an image one line at a time.

The image forming apparatus of the present invention described above is a display apparatus for a television broadcast, a display apparatus such as a video conference system and a computer, and an image forming apparatus as an optical printer using a photosensitive drum or the like. Etc. can also be used.

[0111]

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

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

Step-1 A quartz glass substrate was used as the insulating substrate 1, and 5 nm thick Ti and 30 nm thick Pt were vacuum-deposited on the quartz glass substrate.
Element electrode patterns 2 and 3 were formed by photolithography (FIG. 2A). This device electrode 2,
3 and a 3 nm-thick PdO thin film 4 in the gap
Was formed by photolithography (see FIG. 2).
(B)). The device electrode interval L of the manufactured electron-emitting device is 1
0 μm, and the element electrode length W is 500 μm.

Step-2 The electron-emitting device manufactured as described above was placed in the vacuum container shown in FIG. 4, and the forming process was performed on the electron-emitting device to form an electron-emitting portion 5 (FIG. 2C). ). In the forming process, energization forming in which an electron emission portion 5 is formed by applying an electric current between the (+) electrode and the (-) electrode of the element was used. In this embodiment, the (+) electrode was set to the ground level, and a negative voltage was applied to the (-) electrode side.

The voltage waveform used for the energization forming was a triangular wave pulse having a pulse width of 1 ms and a pulse interval of 10 ms, and the voltage was increased in steps of 2 V / min in 0.1 V steps. When the voltage reached 16 V, the current flowing through the electron-emitting device became almost 0, and the forming was completed.

Step-3 The electron-emitting device subjected to the forming treatment as described above was subjected to an activation treatment. In this embodiment, 1.3 × 1
± 15 V in a benzonitrile atmosphere of 0 ^-4 Pa
The activation process was performed by continuously applying the rectangular pulse of the above. In this embodiment, the (+) electrode is set to the ground level, and a voltage pulse is applied to the (-) electrode. The width of the rectangular pulse was 1 ms, and the pulse interval was 5 ms. The polarity of the pulse was reversed for each pulse, and the pulse was continuously applied for 120 minutes. However, when the activation speed was high, the activation process was terminated when the value of the device current If was saturated even if it did not reach 120 minutes.

By the activation process, the device current If and the emission current Ie, which were almost 0 before the activation process, were significantly increased. The value of the device current If at the end of the activation process was 2.4 mA on average for the 10 devices subjected to the activation process, and the variation was within 10%.

Step-4 Next, oxidation-resistant treatment was performed on the deposited carbon of the electron-emitting device that had been subjected to the activation treatment. In this embodiment, on the electron-emitting device after the activation treatment, adipoyl chloride (chemical formula:
A small amount of ClCO (CH ₂ ) ₄ COCl) was added dropwise. In order to confirm reproducibility, five electron-emitting devices manufactured under the same conditions were used.

After the adipoyl chloride was completely dried, the electron-emitting device was returned to the vacuum processing apparatus again, and heated at 150 ° C. for 8 hours using an ion pump, a turbomolecular pump, and a scroll pump as an exhaust device. And stabilized. In this case, the entire vacuum vessel was also heated.

For the electron-emitting device not subjected to the oxidation-resistant treatment, which is used as a reference sample, the benzonitrile in the vacuum processing apparatus is evacuated after the activation treatment, and the device and the entire vacuum vessel are heated under the same conditions. Stabilized. As a reference sample, five elements were used in order to confirm reproducibility.

Step-5 The electron-emitting device manufactured as described above was driven in the above-described vacuum processing apparatus (measurement and evaluation apparatus), and changes over time in the element current If and the emission current Ie accompanying the driving were observed. Drive the (+) electrode side to ground level,
(-) A voltage pulse was applied to the electrode side. The voltage pulse is a rectangular wave with a pulse width of 0.1 ms and a pulse interval of 1
The driving time was 6.7 msec, and the driving was continued for 24 hours. The degree of vacuum at the time of the measurement was 1.0 × 10 ⁻⁷ Pa. The distance between the anode electrode and the electron-emitting device for measuring emission current was 4 mm, and the potential of the anode electrode was 1 kV.

The values If ₀ and Ie ₀ of the element current If value and the emission current Ie value after being driven for 24 hours at the initial stage of driving.
The ratio with respect to was defined as the daily rate of deterioration rate of the electron-emitting device.

Oxidation-resistant 5 prepared in this example
Table 1 shows measured ratios of If and Ie to the initial values after driving for 24 hours for the element and the five reference sample elements which were not subjected to the oxidation resistance treatment.

[0124]

[Table 1]

As can be seen from Table 1, the device current If and the emission current Ie after driving for 24 hours were reduced to about 50% of the initial values in the five reference sample elements which were not subjected to the oxidation resistance treatment. On the other hand, in the five devices subjected to the oxidation resistance treatment using adipoyl chloride, the device current If and the emission current Ie of about 60% of the initial values can be left after driving for 24 hours, and the effect of preventing the deterioration by the oxidation resistance treatment was confirmed. .

[Embodiment 2] Using the same material and the same size of the electron-emitting devices as used in Embodiment 1, the same procedure and the same conditions as in Embodiment 1 were used for forming the electron-emitting devices.
An activation process was performed. To confirm reproducibility, five devices were subjected to measurement. The device current value at the end of the activation process is 5
The average of the devices is 2.5mA, and the variation between devices is 10%
Was within.

Next, the deposited carbon of the activated electron-emitting device was subjected to an oxidation-resistant treatment. In this embodiment,
After the activation treatment, phosphoric acid butoxide (also known as tri-n-butoxyphosphoric acid, chemical formula: PO (OCH _{2
CH 2 CH 2 CH 3) 3} ) was trace dropwise. After drying the excess phosphoric acid butoxide in an oven at 250 ° C.,
The electron-emitting device was returned to the vacuum processing apparatus again, and was stabilized by heating at 150 ° C. for 8 hours using an ion pump, a turbomolecular pump, and a scroll pump as an exhaust device. In this case, the entire vacuum vessel was also heated.

The electron-emitting device manufactured as described above was driven in the above-mentioned vacuum processing apparatus (measurement and evaluation apparatus), and time-dependent changes in the element current If and the emission current Ie accompanying the driving were observed. The driving conditions, the position of the anode electrode, and the potential of the anode electrode are the same as in the first embodiment. The electron-emitting device is driven for 24 hours, and the device current If value after driving and the emission current Ie value If ₀ , Ie _{0 at the} initial stage of driving.
The ratio with respect to was used as a measure of the deterioration rate of the electron-emitting device.

[0129] The measurement was carried out for five devices subjected to oxidation resistance treatment with butoxide phosphate in this example.
Table 2 shows the ratios of If and Ie to the initial values after the time drive.

[0130]

[Table 2]

As can be seen from Table 2, in the five devices subjected to the oxidation resistance treatment with phosphoric acid butoxide, the device current If and the emission current Ie were 60% or more of the initial values after driving for 24 hours.
And the effect of preventing the deterioration by the oxidation-resistant treatment was confirmed.

[Embodiment 3] Using elements of the same material and the same size as those used in Embodiments 1 and 2,
The forming process and the activating process of the electron-emitting device were performed under the same procedure and under the same conditions. 5 to confirm reproducibility
The device was subjected to measurement. The device current value at the end of the activation process was 2.5 mA on average for the five devices, and the variation between the devices was within 10%.

Next, oxidation-resistant treatment was performed on the deposited carbon of the electron-emitting device that had been subjected to the activation treatment. In this embodiment,
After the activation treatment, triethoxyboron (also called triethyl borate, chemical formula: B (OC ₂ H ₅ )) is formed on the device.
₃ ) was added in a small amount. After drying the excess triethoxyboron in an oven at 120 ° C., the electron-emitting device was returned to the vacuum processing apparatus again, and the ion-emitting device, the turbomolecular pump, and the scroll pump were used as an exhaust device, and the temperature was reduced to 150 ° C. For 8 hours and stabilized. In this case, the entire vacuum vessel was also heated.

The electron-emitting device manufactured as described above was driven in the above-mentioned vacuum processing apparatus (measurement and evaluation device), and time-dependent changes in the device current If and emission current Ie accompanying the drive were observed. The driving conditions, the position of the anode electrode, and the potential of the anode electrode are the same as those in the first and second embodiments.

The electron-emitting device was driven for 24 hours, and the ratio of the device current If value and the emission current Ie value after driving to the values If ₀ and Ie _{0 at the} beginning of driving was used as a measure of the deterioration speed of the electron-emitting device.

The measurement was performed on five devices which were subjected to oxidation resistance treatment with triethoxyboron manufactured in this example and were measured.
Table 3 shows the ratio of If and Ie to the initial values after driving for 4 hours.
Shown in

[0137]

[Table 3]

As can be seen from Table 3, in the five devices subjected to the oxidation resistance treatment with triethoxyboron, the device current If and the emission current I of 60% or more of the initial values after driving for 24 hours.
e could be left, and the effect of preventing deterioration by the oxidation resistance treatment was confirmed.

[Embodiment 4] In this embodiment, an image forming apparatus is manufactured by using an electron source in which a large number of electron-emitting devices are arranged in a simple matrix.

FIG. 12 is a plan view of a part of a substrate on which a plurality of conductive films are arranged in a matrix. Also, A- in FIG.
FIG. 13 shows an A ′ cross-sectional view. However, the same reference numerals in FIGS. 12 and 13 indicate the same members. Here, 71 is a substrate, 2 and 3 are device electrodes, and 4 is a conductive film. 72 is an X-direction wiring (also referred to as a lower wiring) corresponding to Dxm in FIG. 6, 73 is a Y-direction wiring (also referred to as an upper wiring) corresponding to Dyn in FIG. 6, 151 is an interlayer insulating layer, and 152 is an element electrode 2 This is a contact hole for electrical connection with the lower wiring 72.

First, a method of manufacturing an electron source substrate according to this embodiment will be described in the order of steps with reference to FIGS. still,
Steps -a to h described below correspond to (a) to (d) of FIG. 14 and (e) to (h) of FIG. 15, respectively.

Step-a A 50-mm-thick Cr layer and a 6000-mm-thick Au layer are sequentially stacked on a cleaned quartz glass substrate 71 by a vacuum evaporation method, and then a photoresist (AZ1370 / Hoechst) is rotated by a spinner. After coating and baking, the photomask image was exposed and developed to form a resist pattern for the lower wiring 72, and the Au / Cr deposited film was wet-etched to form the lower wiring 72 having a desired shape.

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

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

Step-d Thereafter, a pattern to be the gap L between the device electrodes 2 and 3 and the device electrode is formed by a photoresist (RD-2000N-41).
/ Hitachi Chemical Co., Ltd.) formed and 5n thick by vacuum evaporation
m of Ti and 30 nm of Pt were sequentially deposited. The photoresist pattern was dissolved in an organic solvent, the Pt / Ti deposited film was lifted off, and the element electrode interval L was 10 μm and the width W was 5 μm.
Element electrodes 2 and 3 of 00 μm were formed.

Step-e After a photoresist pattern of the upper wiring 73 was formed on the device electrodes 2 and 3, Ti with a thickness of 50 ° and Au with a thickness of 5000 ° were sequentially deposited by vacuum evaporation. The photoresist pattern was dissolved with an organic solvent, the Au / Ti deposited film was lifted off, and an upper wiring 73 having a desired shape was formed.

Step-f Next, a Cr film 153 having a thickness of 1000 ° is deposited by vacuum evaporation, and then patterned so as to have an opening in the shape of the conductive film 4.
{, 10} was deposited. These film forming conditions have been examined in advance, and the resistance values (Rs) of Pd and Pt are 2 × 10 ⁴ Ω / □ and 5 × 10 ⁵ Ω / □, respectively.

Step-g The Cr film 153 was wet-etched with an acid etchant and removed together with unnecessary portions of the conductive film 4 to form a conductive film 4 having a desired shape.

Step-h A resist pattern having an opening at the contact hole 152 was formed, and 50 .mu.m thick Ti and 5000 .mu.m thick Au were sequentially deposited by vacuum evaporation. Unnecessary portions are removed by lift-off, so that contact holes 1
52 was embedded.

Through the above steps, the lower wiring 72, the interlayer insulating layer 151, the upper wiring 73, the element electrodes 2, 3, and the conductive film 4 composed of the first and second thin films were formed on the insulating substrate 71. The conductive film 4 is subjected to an activation process and an oxidation-resistant process by the above-described method.

Next, an image forming apparatus was manufactured using the substrate 71 (FIG. 12) on which the plurality of conductive films 4 manufactured as described above were arranged in a matrix. 7 and 8 show the fabrication procedure.
This will be described with reference to FIG.

First, a substrate 71 (FIG. 12) on which the plurality of conductive films 4 are arranged in a matrix is fixed on a rear plate 81, and a face plate 86 (on the inner surface of the glass substrate 83) is placed 5 mm above the substrate 71. A fluorescent film 84 and a metal back 85 are formed via a support frame 82, and frit glass is applied to the joint between the face plate 86, the support frame 82, and the rear plate 81. The panel was sealed by baking at 15 ° C. for 15 minutes to form a panel (envelope 88 in FIG. 7). The fixing of the substrate 71 to the rear plate 81 was also performed with frit glass.

The fluorescent film 84 is used to realize color.
A phosphor in the form of a stripe (see FIG. 8A) was formed, a black stripe was formed first, and phosphors 92 of each color were applied to the gaps by a slurry method to form a phosphor film 84. As a material of the black stripe, a material mainly containing graphite, which is generally used, was used.

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

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

At the time of performing the above-mentioned sealing, since the phosphors 92 of each color must correspond to the electron-emitting devices in the case of color, sufficient alignment was performed.

Subsequently, the external terminals Dox1 to Doxm
Then, a pulse voltage was applied between the device electrodes 2 and 3 of the electron-emitting device 74 through Doy1 to Doyn to perform a forming process. In this embodiment, a pulse as shown in FIG. 4B is used, and the pulse width T1 is set to 1 msec. , The pulse interval T2 is 10 msec. And the peak value is from 0 V to 0.1 V
The temperature was gradually raised in steps and performed in a vacuum atmosphere of about 1.3 × 10 ⁻³ Pa.

Next, after evacuating to a degree of vacuum of about 1.3 × 10 ⁻⁴ Pa, the envelope was sealed by heating the exhaust pipe with a gas burner. Finally, in order to maintain the degree of vacuum after sealing, getter processing was performed by a high-frequency heating method to complete the panel.

Next, the external terminals Dox1 to Doxm, Doy1 to Doyn and the high voltage terminal 87 of the panel were connected to necessary driving systems, respectively, to complete the image forming apparatus.
A scanning signal and a modulation signal are applied to the respective electron-emitting devices from signal generating means (not shown) through external terminals Dox1 to Doxm and Doy1 to Doyn, respectively, to emit electrons. The image was displayed by applying the above high pressure, accelerating the electron beam, colliding with the fluorescent film 84, exciting and emitting light.

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

[Embodiment 5] FIG. 16 shows a display panel (FIG. 7) according to Embodiment 4 configured to display image information provided 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.

In the figure, reference numeral 201 denotes a display panel;
1 is a display panel driving circuit, 1002 is a display controller, 1003 is a multiplexer, 10
04 is a decoder, 1005 is an input / output interface circuit, 1006 is a CPU, 1007 is an image generation circuit, 10
08, 1009 and 1010 are image memory interface circuits, 1011 is an image input interface circuit, 1012 and 1013 are TV signal receiving circuits, 101
Reference numeral 4 denotes an input unit.

When the present image forming apparatus receives a signal containing 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 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, a speaker, and the like are omitted.

Hereinafter, the function of each unit 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 format of the received TV signal is not particularly limited. For example, NTSC, PAL, SEC
Any method such as the AM 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. Similarly to the TV signal receiving circuit 1013, the system of the TV signal to be received is not particularly limited, and the TV signal received by this circuit is also output to the decoder 1004.

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

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 this circuit 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 are appropriately selected or combined. In that case, the display panel controller 1
A control signal is generated for 002 to appropriately control the operation of the display device such as the screen display frequency, the scanning method (for example, interlaced or non-interlaced), and the number of scanning lines on one screen. Further, image data and character / graphic information are directly output to the image generation circuit 1007, or image data or character / graphic information is accessed by accessing an external computer or memory via the input / output interface circuit 1005. Enter

It should be noted that the CPU 1006 may be involved in operations 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 1005
The computer may be connected to an external computer network via a computer, and work such as numerical calculation may be performed in cooperation with an external device.

The input unit 1014 is used by 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.
4 preferably has an image memory inside. 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
And cooperate with the CPU 1006 to perform image thinning, interpolation,
There is an advantage that image processing and editing including enlargement, reduction, and composition become easy.

The multiplexer 1003 is connected to 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.

As a signal related to the basic operation of the display panel, for example, a signal for controlling an operation sequence of a display panel driving power supply (not shown) is output to the driving circuit 1001. For example, a signal for controlling a screen display frequency and a scanning method (for example, interlaced or non-interlaced) is output to the driving circuit 1001 as a signal related to the display panel driving method. 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. The drive circuit 1001 is 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 unit has been described above. With the configuration illustrated in FIG. 16, 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 controller 1002 generates a control signal for controlling the operation of the drive circuit 1001 according to an image signal to be displayed. The drive circuit 1001 controls the display panel 201 based on the image signal and the control signal.
Is applied with a drive 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 and the image generation circuit 100
7 and information selected from the information, as well as, for example, enlargement, reduction, rotation, movement, edge enhancement, thinning, interpolation, color conversion, image aspect ratio conversion, etc., for the image information to be displayed. 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 as a television broadcast display device, a video conference terminal device, an image editing device that handles still images and moving images, a computer terminal device,
It can be equipped with the functions of a word processor and other office terminal equipment, game machines, and the like, and has a very wide range of applications for industrial or consumer use.

The display device shown in FIG. 16 can be variously modified based on the technical idea of the present invention. For example, FIG.
Of the six components, circuits relating to functions that are unnecessary for the purpose of use may be omitted. Conversely, additional components may be added depending on the purpose of use. For example, when the present display device is applied as a videophone, it is preferable to add a transmission / reception circuit including a television camera, an audio microphone, an illuminator, and a modem to the components.

In the present display device, in particular, it is easy to reduce the thickness of a display panel using an electron-emitting device as an electron beam source, so that the depth of the display device can be reduced. In addition, since it is easy to increase the area, the brightness is high, and the viewing angle characteristics are excellent, it is possible to display an image full of presence and full of power with good visibility. Further, by using an electron source having a large number of electron-emitting devices having uniform characteristics, a high-quality color flat television that is very uniform and bright compared to a conventional display device has been realized.

[0191]

As described above, according to the present invention,
By subjecting the carbon deposited on the electron-emitting portion by the activation treatment to an oxidation-resistant treatment with a halogen compound, a phosphorus compound, and a boron compound, an electron-emitting device with less deterioration in emission current when the device is driven can be manufactured. it can.

Further, a large number of electron-emitting devices are arranged and formed,
An electron source that emits electrons in response to an input signal can be manufactured stably and with a high yield, and the efficiency can be improved, so that power consumption is reduced, the burden on peripheral circuits and the like is reduced, and an inexpensive device can be provided.

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

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of an electron-emitting device according to the present invention.

FIG. 2 is a diagram illustrating a method for manufacturing an electron-emitting device according to the present invention.

FIG. 3 is a schematic diagram showing an example of a voltage waveform in an energization process that can be employed in manufacturing the electron-emitting device of the present invention.

FIG. 4 is a schematic configuration diagram illustrating an example of a vacuum processing apparatus (measurement evaluation apparatus) that can be used for manufacturing the electron-emitting device of the present invention.

FIG. 5 is a diagram showing the electron emission characteristics of the electron-emitting device of the present invention.

FIG. 6 is a schematic diagram illustrating an example of an electron source having a simple matrix arrangement according to the present invention.

FIG. 7 is a schematic diagram illustrating an example of a display panel of the image forming apparatus of the present invention.

FIG. 8 is a schematic diagram illustrating an example of a fluorescent film in a display panel.

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

FIG. 10 is a schematic diagram showing an example of an electron source having a ladder-type arrangement according to the present invention.

FIG. 11 is a schematic diagram illustrating an example of a display panel of the image forming apparatus of the present invention.

FIG. 12 is a schematic diagram showing a part of an electron source in a matrix wiring according to an example of the present invention.

13 is a schematic cross-sectional view taken along the line A-A 'of FIG.

FIG. 14 is a diagram illustrating a manufacturing process of the electron source in FIG. 12;

FIG. 15 is a view showing a manufacturing process of the electron source of FIG. 12;

FIG. 16 is a block diagram of an image display device according to a fifth embodiment.

FIG. 17 is a schematic view of a conventional surface conduction electron-emitting device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Substrate 2, 3 Element electrode 4 Conductive film 5 Electron emission part 6 Oxidation-resistant carbon 50 Ammeter for measuring element current If 51 Power supply for applying element voltage Vf to electron emission element 52 Electrons Ammeter 53 for measuring emission current Ie emitted from emission unit 5 53 High voltage power supply for applying voltage to anode electrode 54 Anode electrode 55 for capturing electrons emitted from electron emission unit 5 55 Vacuum container 56 Exhaust pump 71 Electron source board 72 X direction wiring 73 Y direction wiring 74 Electron emitting element 75 Connection 81 Rear plate 82 Support frame 83 Glass substrate 84 Fluorescent film 85 Metal back 86 Face plate 87 High voltage terminal 88 Enclosure 91 Black conductive material 92 phosphor 101 display panel 102 scanning circuit 103 control circuit 104 shift register 105 In-memory 106 Synchronous signal separation circuit 107 Modulation signal generator Vx, Va DC voltage source 110 Electron source substrate 111 Electron emission element 112 Common wiring for wiring electron emission element 120 Grid electrode 121 Opening for electrons to pass through 151 interlayer Insulating layer 152 Contact hole 153 Cr film 201 Display panel 1001 Display panel driving circuit 1002 Display controller 1003 Multiplexer 1004 Decoder 1005 Input / output interface circuit 1006 CPU 1007 Image generation circuit 1008, 1009, 1010 Image memory interface circuit 1011 Image input interface circuit 1012 , 1013 TV signal receiving circuit 1014 Input unit

Claims (12)

[Claims] 1. An electron-emitting device having an electron-emitting portion in a conductive film extending between a pair of device electrodes provided on a substrate, wherein carbon deposited on the electron-emitting portion by an activation process is An electron-emitting device that has been subjected to oxidation resistance treatment. 2. The electron-emitting device according to claim 1, wherein the electron-emitting device is a surface conduction electron-emitting device. 3. A method for manufacturing an electron-emitting device according to claim 1, wherein a step of forming a pair of element electrodes on a base, and a step of forming a conductive film extending between the element electrodes. Applying a current between the device electrodes to form an electron-emitting portion in the conductive film; activating an electron-emitting portion to deposit carbon; and performing oxidation-resistant treatment on the carbon deposited in the electron-emitting portion. And a method for manufacturing an electron-emitting device. 4. The method according to claim 3, wherein the oxidation-resistant treatment is a treatment with a halogen compound. 5. The method according to claim 3, wherein the oxidation-resistant treatment is a treatment with a phosphorus compound. 6. The method according to claim 3, wherein the oxidation-resistant treatment is a treatment with a boron compound. 7. An electron source for emitting electrons in response to an input signal, wherein a plurality of the electron-emitting devices according to claim 1 are arranged on a substrate. 8. The electron source according to claim 7, wherein the plurality of electron-emitting devices are wired in a matrix. 9. The electron source according to claim 7, wherein the plurality of electron-emitting devices are wired in a ladder shape. 10. A method for manufacturing an electron source according to claim 7, wherein a plurality of electron-emitting devices are manufactured by the method according to claim 3. Description: Characteristic method of manufacturing an electron source. 11. An apparatus for forming an image based on an input signal, wherein at least the electron source according to claim 7 and an electron beam emitted from the electron source are irradiated with the image. An image forming apparatus, comprising: an image forming member to be formed. 12. A method for manufacturing the image forming apparatus according to claim 11, wherein the electron source is manufactured by the method according to claim 10.