JPH08279335A - Manufacture of electron emitting element, electron source, display panel and image forming device - Google Patents

Abstract

PURPOSE: To obtain a manufacturing method for an electron emitting element, which can form a conductive thin film having uniform surface resistance value independently of the influence of the atmospheric condition such as temperature, oxygen partial pressure, existence of micro quantity of oxidation-reduction material, quantity of steam, degree of vacuum in the heating and burning process. CONSTITUTION: This is a manufacturing method for an electron emitting element having a conductive film 4, which is formed with an electron emitting part 5, between electrodes 2, 3. The process for forming the conductive film 4, which is to be formed with the electron emitting part, includes the process for heating the conductive film forming material, which is provided on a board 1 and which includes the organic metal compound as a main component, in the atmosphere, which includes at least ten times mole of hydrogen sulfide in relation to the quantity of the metal among the organic metal compound.

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 that emits electrons by applying a voltage to a conductive film including an electron-emitting portion provided between opposed electrodes, especially a surface conduction electron-emitting device, an electron source, The present invention relates to a method for manufacturing a display panel and an image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, two types of electron emitters, a thermoelectron source and a cold cathode electron source, are known. Cold cathode electron sources include field emission type (hereinafter abbreviated as FE type), metal / insulating layer / metal type (hereinafter abbreviated as MIM type), surface conduction type electron emitting elements, and the like.

As an example of the FE type electron-emitting device, W.
P. Dyke & W. W. Dolan, "Field e
"Mission", Advance in Elect
ronPhysics, 8, 89 (1956), or C.I. A. Spindt, "Physical Pro"
parts of thin-film field
d emission cathodes with
mollybdenium cones ”, J. App.
l. Phys. , 47, 5248 (1976) and the like are known.

As an example of the MIM type electron-emitting device, C.I. A. Mead, “Operation of
Tunnel-Emission Devices ”,
J. Appl. Phys. , 32,646 (1961)
And the like are known.

As an example of the surface conduction electron-emitting device, M. I. Elinson, Radio Eng.
Electron Phys. , 10, 1290 (19
65) etc. are known.

The surface conduction electron-emitting device utilizes a phenomenon that electron emission occurs when a current is passed through a thin film of a small area formed on a substrate in parallel with the film surface. As the surface conduction electron-emitting device, one using the SnO ₂ thin film by Erinson et al., One using the 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. Fonstad, “IEEE Trans.
ED Conf. , 519 (1975)], by carbon thin film [Hisashi Araki et al., Vacuum, Vol. 26, No. 1]
No., p. 22 (1983)] and the like.

As a typical device configuration of these surface conduction electron-emitting devices, the Hartwell device configuration described above is shown in FIG.
7 shows. In the figure, 1 is a substrate. Reference numeral 4 denotes a conductive film, which is made of a metal oxide thin film or the like formed by sputtering in an H-shaped pattern, and the electron emission portion 5 is formed by an energization process called energization forming described later. The element electrode spacing L in the figure is set to 0.5 to 1 mm, and the element electrode length W'is set to about 0.1 mm. The position and shape of the electron emitting portion 5 are shown as a schematic diagram.

Conventionally, in these surface conduction electron-emitting devices, the electron-emitting portion 5 is generally formed by subjecting the conductive film 4 to an energization process called energization forming in advance before the electron emission. there were. That is, the energization forming means that a direct current voltage or a very slow rising voltage, for example, about 1 V / min is applied to both ends of the electroconductive film 4 to energize the electroconductive film 4 to locally break, deform or deteriorate the electroconductive film 4. This is to form the electron emitting portion 5 in an electrically high resistance state. In the electron emission portion 5, a crack is generated in a part of the conductive film 4, and electrons are emitted from the vicinity of the crack. In this way, the conductive thin film is locally destroyed, deformed or altered by the energization forming, and the site where the structure is changed is called an electron emitting portion 5,
Further, the conductive film 4 on which the electron emitting portion 5 is formed by energization forming is referred to as a conductive film 4 including the electron emitting portion 5. In the surface conduction electron-emitting device that has been subjected to the energization forming treatment, a voltage is applied to the conductive film 4 including the electron-emitting portion 5 described above, and a current is passed through the device, so that electrons are emitted from the electron-emitting portion 5. It is the one to be confused.

Further, the above surface conduction electron-emitting device is
Since the structure is simple and the manufacture is relatively easy, there is an advantage that a large number of elements can be arrayed over a large area. Therefore, various applications that can make full use of this feature have been studied, and examples thereof include a charged beam source and a display device. As an example in which a large number of surface conduction electron-emitting devices are formed in an array, as will be described later, a large number of rows in which both ends of each surface conduction electron-emitting device arranged in parallel are connected by wiring (common wiring) are arranged. An electron source having a so-called ladder type arrangement can be given (for example, Japanese Patent Laid-Open No. 64-03133).
2, JP-A-1-283749, JP-A-2-257552
etc). In addition, in image forming apparatuses such as display devices, in particular, flat panel display devices using liquid crystal have become widespread in place of CRTs in recent years, but they are not self-luminous and therefore have to have a backlight. Therefore, development of a self-luminous display device has been desired. As a self-luminous display device, an image forming apparatus including a display panel in which an electron source in which a large number of surface conduction electron-emitting devices are arranged and a phosphor which emits visible light by electrons emitted from the electron source are combined. (For example, USP 50668
83).

[0010]

However, there are various problems as will be described later regarding the production of these conventional electron-emitting devices, and electron sources, display panels and image forming apparatuses using the same.

That is, conventionally, a solution of an organometallic compound that can be thermally decomposed at a relatively low temperature is applied and dried, and then heated and fired in a firing atmosphere such as an air atmosphere to thermally decompose and remove an organic component to remove metal or metal. Although it was an oxide, in such a conventional method, the temperature in the heating and firing step, the oxygen partial pressure, the presence of a trace amount of redox substances, the amount of water vapor,
There has been a problem that the mixing ratio of the metal and the metal oxide changes depending on the atmospheric conditions such as the degree of vacuum and the surface resistance value of the obtained conductive thin film changes.

Therefore, in the electron-emitting device obtained through the above conventional heating and firing process, there is a limit to the uniformization of the surface resistance value (sheet resistance value) of the conductive thin film, and therefore the voltage / current during the forming treatment is limited. And the device characteristics are unstable with no reproducibility. Therefore, even in an electron source, a display panel and an image forming apparatus using such an electron-emitting device, unevenness in brightness and defects in the electron-emitting portion may cause defects. There was a limit to the reduction of non-defective product generation rate.

The organic metal compound is used for forming the conductive film because it is heated and baked at a temperature lower than the heat resistant temperature of the glass or silicon wafer, which is generally used as the substrate of the electron-emitting device, and the electrode material. This is because a metal or a metal oxide can be obtained by the method.
On the other hand, metal halides and inorganic acid salts containing no organic component generally have a melting point, boiling point, sublimation temperature, and decomposition temperature of about 1000 ° C, and need to be heated and fired at a temperature much higher than the above heat-resistant temperature. Is not suitable.

The present invention has been made in view of the problems of the prior art described above, and the temperature in the heating and firing step,
A method for manufacturing an electron-emitting device capable of forming a conductive film having a uniform surface resistance value without being affected by atmospheric conditions such as oxygen partial pressure, the presence of a trace amount of redox substances, the amount of water vapor, and the degree of vacuum. It is an object of the present invention to develop and further provide a method of manufacturing an electron source, a display panel and an image forming apparatus using the method.

[0015]

Means for Solving the Problems As a result of intensive studies aimed at achieving the above object, the present inventors have found that an inorganic metal sulfide is used as a main component by heating and firing an organometallic compound in a firing atmosphere containing hydrogen sulfide. As a conductive film is obtained, the surface resistance value of the conductive film containing such an inorganic metal sulfide as the main component is the temperature in the heating and firing step, the oxygen partial pressure, the presence of a trace amount of a redox substance, the amount of water vapor, The present invention has been completed by finding that the uniformity is less likely to be influenced by the atmospheric conditions such as the degree of vacuum.

That is, the present invention relates to a novel method of manufacturing an electron-emitting device and a method of manufacturing an electron source, a display panel and an image forming apparatus using the method, which will be described in detail below.

First, a method of manufacturing the novel electron-emitting device of the present invention will be described.

The method of manufacturing an electron-emitting device according to the present invention is the method of manufacturing an electron-emitting device having a conductive film having an electron-emitting portion formed between electrodes, in which a conductive film having an electron-emitting portion is formed. An atmosphere in which the step contains the conductive film-forming material containing an organometallic compound as a main component, which is provided on the substrate, and contains hydrogen sulfide in an amount of at least 10 times the molar amount of the metal in the organometallic compound. The method is characterized by a method of manufacturing an electron-emitting device characterized by including a step of heating the inside.

In the method for producing an electron-emitting device of the present invention, first, a conductive film forming material containing an organometallic compound as a main component is applied as a solution onto the substrate, if necessary. The method is not particularly limited, and a coating method, a vacuum vapor deposition method, a sputtering method, a chemical vapor deposition method, a dispersion coating method, a dipping method, a spinner method or the like is appropriately adopted.

The conductive film forming material used in the present invention is not particularly limited as long as it contains an organometallic compound as a main component, but as the conductive film forming material suitable for the present invention, For example, the following general formula (1)

[0021]

A carboxylic acid represented by (C _n H _{2n + 1} COO) _m M (1) (wherein n is an integer of 1 to 6, m is an integer of 1 to 4, and M is a metal). The thing containing a metal salt as an organometallic compound is mentioned. Also,
In the present invention, those containing a complex of the above carboxylic acid metal salt are also suitably used as the organometallic compound.

The central metal (M) in the organometallic compound such as the carboxylic acid metal salt is preferably one that easily emits electrons when a voltage is applied, that is, one that has a relatively low work function and is stable, for example, Pd, Ru, A
g, Au, Ti, In, Cu, Cr, Fe, Zn, S
n, Ta, W, Pb, Tl, Hg, Cd, Pt, Mn,
Sc, Y, La, Co, Ce, Zr, Th, V, Mo,
Metals such as Ni, Os, Rh and Ir may be mentioned.

In the above carboxylic acid metal salt, the number (m) of carboxylic acid moieties bonded to the metal varies from 1 to 4 depending on the valence of the metal ion. For example, in the case of silver and carboxylic acid, silver monocarboxylate in which 1 equivalent of carboxylic acid is bonded to 1 equivalent of silver is generally used, and in the case of palladium and carboxylic acid, 1 equivalent of palladium is used. It is well known that palladium dicarboxylate having 2 equivalents of carboxylic acid bonded thereto is common. It is well known that yttrium tricarboxylate is generally used in the case of yttrium (Y) and carboxylic acid, and lead tetracarboxylate is commonly used in the case of lead (Pb) and carboxylic acid.

The organometallic compound such as the carboxylic acid metal salt is used as a solution, if necessary. As a solvent when the conductive film forming material used in the present invention is a solution, considering the solubility of the organometallic compound in the solvent and conditions such as drying at the time of film formation, ketones, ethers, carvone, etc. Preference is given to acid esters, alcohols or water.

The above-mentioned organometallic compound according to the present invention is generally insulative, and if it is left as it is, the electrical treatment called energization forming described below cannot be carried out. Therefore, the material applied on the substrate is appropriately dried and then heated and baked. In the present invention, such heating and baking is performed at least 10 times with respect to the amount of metal in the organometallic compound applied on the substrate.
Conducting in a firing atmosphere containing a double molar amount of hydrogen sulfide, thereby obtaining a conductive film containing an inorganic metal sulfide as a main component. More specifically, the substrate coated with the organometallic compound is heated in the firing atmosphere to a temperature above the decomposition temperature of the organometallic compound to decompose the organic component of the organometallic compound on the substrate to obtain a conductive film. During the heating and firing process, thiocarboxylic acid, carbon disulfide, carbon dioxide, etc. are decomposed and formed, and a metal sulfide in which a sulfur atom is bonded to a metal is formed.

In the present invention, the amount of hydrogen sulfide in the firing atmosphere is at least 10 times the molar amount of the metal in the organometallic compound provided on the substrate for the following reason.
That is, for example, since the metal sulfide of a tetravalent metal is MS _2, it requires at least twice the molar amount of hydrogen sulfide with respect to the metal. Further, in the actual reaction between the organometallic compound and hydrogen sulfide, since there are not a few sulfur atoms which react with not only the metal but also carbon, hydrogen sulfide in an amount of at least 10 times the amount of the above metal is present. You need it.

As the gas component other than hydrogen sulfide in the firing atmosphere in the present invention, oxygen, nitrogen, helium and the like are generally used. When oxygen is used, metal oxides may be formed kinetically, but since sulfides have stronger bonds with metals than oxides, they become metal sulfides in the equilibrium state. That is, after a sufficient firing time, the metal becomes a sulfide instead of an oxide.

The temperature and time for heating and firing the above materials are appropriately selected so that the organic substance of the organometallic compound used is decomposed to become an inorganic metal sulfide. The organic component of the organometallic compound is 1000 ° C. or less, and in most cases 300 ° C.
The temperature for heating the substrate is preferably 200 ° C. to 500 ° C. because it decomposes before and after it changes to an inorganic metal sulfide or a compound in which an organic substance having a small carbon number is adsorbed on the surface thereof.

Further, it is preferable that 90% or more of the organic component of the organometallic compound is decomposed during heating and firing, that is, 90% or more of the organometallic compound is made into an inorganic metal sulfide. This is because if it is within this range, the electric resistance of the obtained conductive film becomes low, and the energization forming process tends to be surely performed. The remaining part (preferably 10% or less of the component) is organic matter or H ₂ O,
CO, NO _x, etc., but depending on the central metal of the organometallic compound, it may not be possible to completely adsorb, occlude, and coordinate these metals for complete removal. It is preferable that these residues do not exist, but they may exist in a range in which electric resistance capable of performing the energization forming process is secured.

The drying step is carried out by appropriately adopting normally used natural drying, blast drying, heat drying and the like, and the baking step is also carried out by appropriately adopting commonly used heating means. It is not always necessary to perform the process separately from the process, and it may be performed continuously and simultaneously.

Then, in the method of manufacturing an electron-emitting device according to the present invention, the above-mentioned conductive film is subjected to an energization forming treatment to form the above-mentioned electron-emitting portion. The energization forming process is a process for forming an electron-emitting portion by locally applying a voltage such as a pulse waveform to the conductive film to locally destroy, deform, or deteriorate the conductive film. It is appropriately selected depending on the film thickness, film quality, material, etc. of the flexible film.

In the method for manufacturing an electron-emitting device of the present invention, since the organometallic compound provided on the substrate as described above is heated and fired in a firing atmosphere containing hydrogen sulfide, the inorganic metal is passed through the heating and firing step. A conductive film containing sulfide as a main component is obtained. Such a sulfide has a stronger bond with a metal than an oxide, is less likely to generate a free metal ion, and is characterized by being hardly soluble in water. Therefore, the conductive film containing the inorganic metal sulfide as a main component obtained in the method of the present invention, since the metal sulfide is more stable than the metal oxide, the oxygen partial pressure and the degree of vacuum in the heating and firing step change. Also exists as a sulfide, has a property that the metal is difficult to be ionized, is not easily affected by a redox substance, and is difficult to react with water because it is hardly soluble in water. Further, the characteristics of these metal sulfides are not easily influenced by temperature, and the metal sulfides are stable because they are less likely to be a metal than the metal oxides.

Therefore, in the method of the present invention in which the organometallic compound provided on the substrate is heated and fired in the firing atmosphere containing hydrogen sulfide, the temperature, oxygen partial pressure, and a trace amount of the redox substance in the heating and firing step are used. , The amount of water vapor, the degree of vacuum, etc., the surface resistance value of the conductive film can be obtained because the conductive film containing an inorganic metal sulfide as a main component and having a stable composition can be obtained without being affected by atmospheric conditions. It is uniform without variation. In the range of the angstrom order of the thin film, these inorganic metal sulfides are often aggregated into a fine particle shape. That is, the number of molecules such as an inorganic metal sulfide contained in an organometallic compound and produced by firing agglomerates from a few to a few thousand to form fine particles, but according to the present invention, agglomeration of a size visible to the naked eye. Does not happen.

The basic structure of the electron-emitting device that can be manufactured by the above-described method for manufacturing an electron-emitting device of the present invention is not particularly limited, but the basic structure of a preferable electron-emitting device will be described below with reference to the drawings. To do.

The basic structure of the electron-emitting device suitable for the present invention includes two structures, a flat type and a vertical type.
First, the planar electron-emitting device will be described.

1 (a) and 1 (b) are a schematic plan view and a sectional view, respectively, showing the basic structure of a planar electron-emitting device suitable for the present invention. In FIG. 1, 1 is an insulating substrate, 2 and 3 are device electrodes, 4 is a conductive film, and 5 is an electron emitting portion.

As the substrate 1, quartz glass, glass having a reduced content of impurities such as Na, soda lime glass, a soda lime glass substrate laminated with SiO ₂ formed by a sputtering method or the like, and ceramics such as alumina are used. Used.

Element electrodes 2 and 3 arranged on the substrate 1 so as to face each other.
As the material of the above, a general conductor material is used, for example, Ni, Cr, Au, Mo, W, Pt, Ti, Al, C.
u, Pd and other metals or their alloys, Pd, Ag,
A printed conductor composed of a metal or metal oxide such as Au, RuO ₂ , Pd-Ag or the like and glass, In ₂ O ₃ -S
It is appropriately selected from transparent conductors such as nO ₂ and semiconductor conductor materials such as polysilicon.

The element electrode spacing L, the element electrode length W, the shape of the conductive film 4 and the like are appropriately designed according to the applied form and the like. The element electrode distance L is preferably several hundred angstroms to several hundreds of μm, and more preferably several μm to several tens of μm depending on the voltage applied between the device electrodes. Further, the device electrode length W is preferably several μm to several hundreds μm depending on the resistance value of the electrode, electron emission characteristics and the like. further,
The film thickness d of the device electrodes 2 and 3 is preferably several hundred angstroms to several μm.

In FIG. 1, the device electrodes 2 and 3 and the conductive film 4 are sequentially laminated on the substrate 1, but the electron-emitting device suitable for the present invention is not limited to such a structure, and the substrate 1
Alternatively, the conductive film 4 and the device electrodes 2 and 3 may be sequentially stacked on top of each other.

The conductive film 4 contains an inorganic metal sulfide as a main component, which is obtained by heating and baking the conductive film forming material in a baking atmosphere containing hydrogen sulfide as described above. Therefore, as the material forming the conductive film 4, for example, Pd, Ru, Ag, Au, Ti, In, Cu, C
r, Fe, Zn, Sn, Ta, W, Pb, Tl, Hg,
Cd, Pt, Mn, Sc, Y, La, Co, Ce, Z
Examples thereof include sulfides of metals such as r, Th, V, Mo, Ni, Os, Rh, and Ir.

The conductive film 4 is particularly preferably a fine particle film composed of fine particles in order to obtain good electron emission characteristics.
Note that the fine particle film described here is a film in which a plurality of fine particles are aggregated, and its fine structure is not only in a state in which the fine particles are individually dispersed and arranged, but also in a state in which the fine particles are adjacent to each other or overlap each other (also in an island shape). Including) film. The particle size of such fine particles is preferably several angstroms to several thousand angstroms, particularly preferably 10 angstroms to 200 angstroms.

The film thickness of the conductive film 4 is appropriately set depending on the step coverage to the device electrodes 2 and 3, the resistance value between the device electrodes 2 and 3 and the energization forming processing conditions described later, and preferably from several angstroms to several angstroms. It is 1,000 angstroms, and particularly preferably 10 angstroms to 500 angstroms. A preferred resistance value of the conductive film 4 is a sheet resistance value of 10 2 to 10 7 Ω / □.

The electron emitting portion 5 is a high-resistance crack formed in a part of the conductive film 4, and the film thickness, film quality of the conductive film 4,
It is formed depending on the material and the energization forming processing conditions described later. Further, the electron emitting portion 5 may have conductive fine particles having a particle diameter of several angstroms to several hundred angstroms. Such conductive fine particles are used as the conductive film 4
It is the same as a part or all of the elements of the material constituting the. Further, the electron emitting portion 5 and the conductive film 4 in the vicinity thereof may contain carbon and a carbon compound. Although it is illustrated in FIG. 1 that a part of the conductive film 4 between the device electrodes 2 and 3 functions as the electron emitting portion 5, depending on the manufacturing method, it may be provided between the device electrodes 2 and 3. Conductive film 4
In some cases, all function as the electron emitting portion 5.

Next, a vertical type electron-emitting device which is an electron-emitting device having another structure suitable for the present invention will be described.

FIG. 2 is a schematic sectional view showing the basic structure of a vertical electron-emitting device suitable for the present invention. In FIG. 2, the same reference numerals as those in FIG. 1 denote the same parts as those in FIG. 1, and reference numeral 21 denotes a step forming portion.

Substrate 1, device electrodes 2 and 3, conductive film 4,
The electron emitting portion 5 is made of a material similar to that of the above-mentioned planar type electron emitting device, and the step forming portion 21 is made of an insulating material such as SiO ₂ formed by a vacuum deposition method, a printing method, a sputtering method or the like. Composed of a conductive material. The thickness of the step forming portion 21 is
Corresponding to the device electrode spacing L of the flat-type electron-emitting device described above, it is preferably several hundred angstroms to several tens of μm, the manufacturing method of the step forming portion, the voltage applied between the device electrodes, and the electric field strength capable of emitting electrons. And more preferably from several hundred angstroms to several μm.

Since the conductive film 4 is formed after the device electrodes 2 and 3 and the step forming portion 21 are formed, it is laminated on the device electrodes 2 and 3. Although the electron emitting portion 5 is shown as a straight line with respect to the step forming portion 21 in FIG. 2, the shape and position are not limited to this, depending on the manufacturing conditions, the energization forming conditions, and the like. .

Further, the method of manufacturing the electron-emitting device of the present invention may be any method as long as the above conditions are satisfied, and various concrete methods can be considered. One example is shown in FIG.

Hereinafter, preferred embodiments of the method for manufacturing an electron-emitting device according to the present invention will be described in order with reference to FIGS. 1 and 3. In FIG. 3, the same reference numerals as those in FIG. 1 denote the same parts as those in FIG.

1) After the substrate 1 is thoroughly washed with a detergent, pure water and an organic solvent, a device electrode material is deposited on the substrate 1 by a vacuum vapor deposition method, a sputtering method or the like, and then on the substrate 1 by a photolithography technique. Element electrodes 2 and 3 are formed on the substrate (FIG. 3A).

2) On the substrate 1 provided with the device electrodes 2 and 3,
An organic metal thin film is formed by applying the conductive film forming material as a solution and leaving it to stand. The above solution is a solution containing an organometallic compound such as the carboxylic acid metal salt. Thereafter, the organic metal thin film is heated and baked in the baking atmosphere containing hydrogen sulfide as described above, and is patterned by lift-off, etching or the like to form the conductive film 4 containing an inorganic metal sulfide as a main component. (FIG.3 (b)). Although the method of applying the solution of the material for forming the conductive film has been described here, the means for applying the material onto the substrate is not limited to this, and the vacuum deposition method, the sputtering method, the chemical vapor deposition method It is also possible to apply by a dispersion coating method, a dipping method, a spinner method, or the like.

3) Subsequently, a current is applied between the device electrodes 2 and 3 using a power source (not shown) to subject the conductive film 4 to an energization process called energization forming, so that the portion of the conductive film 4 is structured. The changed electron emission portion 5 is formed (FIG. 3).
(C)).

FIG. 4 shows an example of a voltage waveform during energization forming.

A pulse waveform is particularly preferable as the voltage waveform, and FIG. 4 (a) shows a case where a pulse having a constant pulse voltage is applied, and FIG. 4 (a) shows a case where a pulse is applied while increasing the pulse wave value. 4 (b), respectively.

First, the case where the pulse peak value is a constant voltage will be described with reference to FIG. In FIG. 4A, T1 and T2 are the pulse width and pulse interval of the voltage waveform, respectively. T1 is 1 microsecond to 10 milliseconds, T
2 is 10 microseconds to 100 milliseconds, and the peak value of the triangular wave (peak voltage during energization forming) is appropriately selected according to the above-described form of the electron-emitting device, and a suitable vacuum degree, for example, 10 −5 torr. It is applied for several seconds to several tens of minutes in a vacuum atmosphere of a certain degree. The voltage waveform applied between the electrodes of the element is not limited to the triangular wave, and a desired waveform such as a rectangular wave may be adopted.

T1 and T2 in FIG. 4B are shown in FIG.
As in (a), the crest value of the triangular wave is
For example, the voltage is applied in an appropriate vacuum atmosphere while increasing in steps of about 0.1 V.

In the above case, the energization forming process is terminated by measuring the device current during the pulse interval T2 at a voltage that does not locally break or deform the conductive film 4, for example, a voltage of about 0.1V. Then, the resistance value is obtained, and the energization forming is terminated when the resistance value is, for example, 1 M ohm or more.

4) Next, the element for which the energization forming has been completed is preferably subjected to a treatment called an activation step.

The activation process is, for example, 10 −4 to 1
This is a process of repeating application of a pulse having a constant pulse voltage with a constant voltage at a vacuum degree of about 0 −5 torr, as in the case of energization forming. The organic substance present in the vacuum is applied to the conductive film 4 by such treatment. Carbon and a carbon compound are deposited on the surface of the device, and thereby the device current If and the emission current Ie are significantly changed. While measuring the device current If and the emission current Ie, for example, the activation process is terminated when the emission current Ie is saturated. Further, the pulse peak value is preferably an operation drive voltage.

The carbon and carbon compound referred to here are graphite (indicating both single and polycrystalline) and amorphous carbon (indicating a mixture of amorphous carbon and polycrystalline graphite), and their film thickness. Is preferably 500 angstroms or less, more preferably 300 angstroms or less.

5) It is preferable that the electron-emitting device thus produced is operated and held in a vacuum atmosphere having a vacuum degree higher than those in the forming step and the activation step.
Further, in a vacuum atmosphere having a higher degree of vacuum as described above, 80 ° C to
More preferably, it is operated after being heated to 150 ° C.

A vacuum atmosphere having a vacuum degree higher than the vacuum degree in the forming step and the activation step is, for example, about 10.
Is a vacuum degree having a vacuum degree of −6 or higher, more preferably an ultra-high vacuum system, and a vacuum degree at which carbon and a carbon compound are not newly deposited.

Therefore, it becomes possible to suppress the deposition of carbon and carbon compounds more than those deposited in the activation step, and the device current If and emission current Ie are stabilized.

Basic characteristics of the electron-emitting device having the above-described device structure and manufactured by the manufacturing method of the present invention will be described with reference to FIGS. 5 and 6.

FIG. 5 is a schematic configuration diagram of a measurement / evaluation apparatus for measuring the electron emission characteristics of the element having the configuration shown in FIG. 5, the same reference numerals as those in FIG. 1 indicate the same parts as those in FIG. Further, 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 emission of the device. An anode electrode for capturing the emission current Ie emitted from the portion 5, 53 is a high voltage power source for applying a voltage to the anode electrode 54, 5
2 is an ammeter for measuring the emission current Ie emitted from the electron emission portion 5 of the device, 55 is a vacuum device, and 56 is an exhaust pump.

Further, the electron-emitting device and the anode electrode 54
Etc. are installed in a vacuum device 55, and the vacuum device 55 is equipped with equipment necessary for a vacuum device such as a vacuum gauge (not shown) so that measurement and evaluation of the electron-emitting device can be performed under a desired vacuum. It has become. The exhaust pump 56 is composed of a normal high vacuum system including a turbo pump and a rotary pump, and an ultra high vacuum system including an ion pump. The entire vacuum device and the electron-emitting device can be heated up to 200 degrees by a heater (not shown). Therefore, the present measurement and evaluation apparatus can also perform the steps after the above-described energization forming.

The voltage of the anode electrode is 1 kV to 10 kV.
kV, the distance H between the anode electrode and the electron-emitting device is 2 mm
It was measured in the range of ~ 8 mm.

FIG. 6 shows a typical example of the relationship between the emission voltage Ie and the device current If and the device voltage Vf measured by the measurement / evaluation apparatus shown in FIG. Since the emission current Ie is remarkably smaller than the device current If, FIG. 6 shows the linear scale in arbitrary units.

As is clear from FIG. 6, the electron emission device manufactured by the manufacturing method of the present invention has the emission current Ie.
Has the following three characteristic properties.

First of all, when a device voltage higher than a certain voltage (called a threshold voltage, which is Vth in FIG. 6) is applied to the electro-emission device, the emission current Ie rapidly increases,
On the other hand, if it is less than the threshold voltage Vth, the emission current Ie is hardly detected. That is, the electro-emission device is a non-linear device having a clear threshold voltage Vth with respect to the emission current Ie.

Secondly, since the emission current Ie monotonically increases with the element voltage Vf, the emission current Ie can be controlled by the element voltage Vf.

Thirdly, the emitted charges captured by the anode electrode 54 depend on the time for 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 for which the device voltage Vf is applied.

Since the electron-emitting device manufactured by the manufacturing method of the present invention has the characteristics as described above, the electron-emitting characteristics of the electron source, the image forming apparatus, etc., in which a plurality of electron-emitting devices are arranged, depend on the input signal. Can be easily controlled, and can be applied to various fields.

Further, an example of a preferable characteristic in which the element current If monotonically increases with respect to the element voltage Vf (called MI characteristic) is shown by a solid line in FIG. 6, but in addition to this, the element current If is equal to the element voltage Vf. There is also a case where a voltage control type negative resistance (called VCNR characteristic) characteristic is shown with respect to Vf (not shown in FIG. 6). In addition, the characteristics of these device currents depend on the manufacturing method and the measurement conditions at the time of measurement. Also in this case, the electron-emitting device has the three characteristic features described above.

Next, the method of manufacturing the electron source of the present invention and the electron source manufactured by the method will be described.

The method of manufacturing an electron source of the present invention is a method of manufacturing an electron source comprising an electron-emitting device and means for applying a voltage to the device. This is a method characterized by being manufactured by a method of manufacturing an element. The method of manufacturing the electron source of the present invention is not particularly limited except that the electron-emitting device is manufactured by the above-described method of manufacturing the electron-emitting device of the present invention, and the voltage applying means of the electron source manufactured by such a method. The specific configuration such as is not particularly limited.

The preferred embodiments of the electron source manufacturing method of the present invention and the electron source manufactured by the method will be described below.

The arrangement method of the electron-emitting devices on the substrate is as follows.
For example, as described in the conventional example, a large number of electron-emitting devices are arranged in parallel, and a large number of rows of electron-emitting devices in which both ends of each device are connected by wiring are arranged (referred to as row direction) In a direction (called a column direction) in which a control electrode (also referred to as a grid) installed in a space above the electron source controls and drives the emitted electrons from the electron-emitting device in a ladder-like arrangement, An arrangement in which n Y-direction wirings are provided on the X-direction wirings via an interlayer insulating layer and the X-direction wirings and the Y-direction wirings are connected to a pair of device electrodes of the electron-emitting device, respectively. Hereinafter, the latter arrangement will be referred to as a simple matrix arrangement. First, the simple matrix arrangement will be described in detail.

According to the characteristics of the three basic characteristics of the electron-emitting device manufactured by the above-described manufacturing method of the present invention, even in the electron-emitting device arranged in the simple matrix, the emitted electrons from the device are the threshold. Above the value voltage, it is controlled by the peak value and the width of the pulse voltage applied between the opposing element electrodes. On the other hand, below the threshold voltage, almost no emitted electrons are emitted. According to this characteristic, even when a large number of electron-emitting devices are arranged, if the pulsed voltage is appropriately applied to each device, the electron-emitting device is selected according to the input signal and the electron emission amount is controlled. It is possible to

The structure of the electron source constructed based on this principle will be described below with reference to FIG. 71 is an electron source substrate, 72 is an X-direction wiring, 73 is a Y-direction wiring, 74 is an electron-emitting device, and 75 is a connection. The electron-emitting device 7
No. 4 is required as long as it is manufactured by the above-described manufacturing method of the present invention, and may be either the above-mentioned plane type or vertical type.

In FIG. 7, the electron source substrate 71 is the above-mentioned glass substrate or the like, and the number of electron-emitting devices to be installed and the design shape of each device are appropriately set according to the application.

The X-direction wirings 72 are Dx1, Dx2, ...
., Dxm (m is a positive integer) wiring, and is a conductive metal or the like formed on the electron source substrate 71 by a vacuum deposition method, a printing method, a sputtering method, or the like. Further, the material, the film thickness, and the wiring width are appropriately set so that a substantially uniform voltage is supplied to many electron-emitting devices. Y direction wiring 73 is Dy
1, Dy2, ..., Dyn (n is a positive integer) wirings, and is manufactured in the same manner as the X-direction wiring 72. An interlayer insulating layer (not shown) is provided between the m X-direction wirings 72 and the n Y-direction wirings 73, and they are electrically separated to form a matrix wiring.

The interlayer insulating layer (not shown) is SiO ₂ or the like formed by a vacuum evaporation method, a printing method, a sputtering method or the like, and has a desired shape on the entire surface or a part of the substrate 71 on which the X-direction wiring 72 is formed. Formed, especially the X-direction wiring 72 and the Y-direction wiring 7
The film thickness, the material, and the manufacturing method are appropriately set so as to withstand the potential difference at the intersection of Nos. The X-direction wiring 72 and the Y-direction wiring 73 are drawn out as external terminals.

Further, opposing device electrodes (not shown) of the electron-emitting device 74 are formed by m X-direction wirings 72 and n Y-direction wirings 73 by a vacuum evaporation method, a printing method, a sputtering method or the like. Further, they are electrically connected to each other by a connecting wire 75 made of a conductive metal or the like.

Here, m X-direction wirings 72 and n Y-direction wirings are provided.
The directional wiring 73, the connecting wire 75, and the conductive metal of the opposing element electrodes may be the same or different in some or all of their constituent elements, and are appropriately selected from the above-described element electrode materials and the like. To be done. Wirings to these element electrodes may be collectively referred to as element electrodes when the same wiring material is used for the element electrodes. The electron-emitting device may be formed either on the substrate 71 or on an interlayer insulating layer (not shown).

Further, as will be described in detail later, a scanning (not shown) for applying a scanning signal for scanning the row of the emission elements 74 arranged in the X direction according to the input signal, on the X-direction wiring 72. The signal generating means is electrically connected.
On the other hand, the Y-direction wiring 73 is electrically provided with a modulation signal generating means (not shown) for applying a modulation signal for modulating each of the columns of the emission elements 74 arranged in the Y direction according to an input signal. It is connected. Further, the driving voltage applied to each element of the electron-emitting device is supplied as a difference voltage between the scanning signal and the modulation signal applied to the element.

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

Next, the display panel manufacturing method of the present invention,
A display panel manufactured by the method will be described.

The display panel manufacturing method of the present invention comprises an electron source having an electron-emitting device and means for applying a voltage to the device, and a fluorescent film which emits light upon receiving electrons emitted from the device. A method of manufacturing a panel, characterized in that the electron-emitting device is manufactured by the above-described method of manufacturing an electron-emitting device of the present invention. In the manufacturing method of the display panel of the present invention, the electron-emitting device is not particularly limited except that it is manufactured by the above-described manufacturing method of the electron-emitting device of the present invention, and the electron source of the display panel manufactured by such a method, The specific configuration of the fluorescent film or the like is not particularly limited.

As a preferred embodiment of the display panel manufacturing method of the present invention and the display panel manufactured by the method, a display panel used for display by the electron source having the simple matrix arrangement manufactured as described above will be described. , FIG. 8 and FIG. 9. FIG. 8 is a basic configuration diagram of the display panel, and FIG. 9 is a pattern diagram of the fluorescent film.

In FIG. 8, 71 is an electron source substrate on which the electron-emitting devices are arranged as described above, 81 is a rear plate on which the electron source is fixed, and 86 is a fluorescent film 84 and a metal back 85 on the inner surface of the glass substrate 83. And a reference numeral 82 is a support frame, and the rear plate 81, the support frame 82, and the face plate 86 are coated with frit glass or the like in the air or a nitrogen atmosphere in a range of 400-5.
The envelope 88 is configured by sealing by firing at 00 degrees for 10 minutes or more.

In FIG. 8, 74 corresponds to the electron emitting portion in FIG. Reference numerals 72 and 73 are an X-direction wiring and a Y-direction wiring connected to the pair of device electrodes of the electron-emitting device, respectively.

As described above, the envelope 88 is composed of the face plate 86, the support frame 82 and the rear plate 81. Since the rear plate 81 is provided mainly for the purpose of reinforcing the strength of the substrate 71, the substrate When the 71 itself has a sufficient strength, the separate rear plate 81 is not necessary, and the support frame 82 is directly sealed to the substrate 71, and the face plate 8
The envelope 88 may be composed of the support frame 82 and the substrate 71. Furthermore, by providing a support member (not shown) called a spacer between the face plate 86 and the rear plate 81, the envelope 88 having sufficient strength against atmospheric pressure is formed. You can also

FIG. 9 shows a fluorescent film. The fluorescent film 84 is composed of only the phosphor in the case of monochrome, but in the case of the color fluorescent film, it is composed of a black conductive material 91 called a black stripe or a black matrix depending on the arrangement of the phosphor and a phosphor 92. It The purpose of providing the black stripes and the black matrix is to make the color mixture or the like inconspicuous by blackening the separately-applied portions between the phosphors 92 of the three primary color phosphors required for color display, and in the phosphor film 84. This is to suppress a decrease in contrast due to reflection of external light. The material of the black stripe is not limited to the commonly used material containing graphite as a main component, but is not limited to this as long as it is a material having conductivity and little light transmission and reflection.

As a method for applying the phosphor to the glass substrate 83, a precipitation method or a printing method is used regardless of monochrome or color.

A metal back 85 is usually provided on the inner surface of the fluorescent film 84. The purpose of the metal back is to improve the brightness by specularly reflecting the light to the inner surface side of the light emitted from the phosphor to the face plate 86 side, to act as an electrode for applying an electron beam acceleration voltage, and This is to protect the phosphor from damage caused by collision of negative ions generated in the enclosure. 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 by vacuum evaporation or the like.

The face plate 86 is further provided with the fluorescent film 8
In order to improve the conductivity of No. 4, a transparent electrode (not shown) may be provided on the outer surface side of the fluorescent film 84.

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

The envelope 88 is connected to the outside through an exhaust pipe (not shown).
The degree of vacuum is set to about 0 to the minus 7th power [Torr], and sealing is performed. Further, a getter process may be performed in order to maintain the degree of vacuum after the envelope 88 is sealed. This is to heat the getter arranged at a predetermined position (not shown) in the envelope 88 by a heating method such as resistance heating or high frequency heating immediately before or after the envelope 88 is sealed. , A process of forming a vapor deposition film. The getter usually has Ba as a main component, and due to the adsorption action of the deposited film, for example, 1 × 10 to the minus 5th power or 1 × 1.
The degree of vacuum of 0 minus 7 torr is maintained. The steps after forming the electron-emitting device are
It is set appropriately.

Next, a method for manufacturing an image forming apparatus of the present invention and an image forming apparatus manufactured by the method will be described.

The method of manufacturing an image forming apparatus of the present invention comprises an electron source having an electron-emitting device and means for applying a voltage to the device, a fluorescent film which emits light upon receiving electrons emitted from the device, and an external signal. And a drive circuit for controlling a voltage applied to the device based on the above, wherein the electron-emitting device is manufactured by the above-described method for manufacturing an electron-emitting device of the present invention. Is the method. The method of manufacturing the image forming apparatus of the present invention is not particularly limited except that the electron-emitting device is manufactured by the method of manufacturing the electron-emitting device of the present invention described above, and the electron of the image forming apparatus manufactured by such a method is not limited. The specific configurations of the source, the fluorescent film, the driving circuit, etc. are not particularly limited.

Hereinafter, as a preferred embodiment of the method of manufacturing an image forming apparatus of the present invention and the image forming apparatus manufactured by the method, an NTSC system using a display panel configured by using an electron source having a simple matrix arrangement is adopted. An image forming apparatus for performing television display based on a television signal is shown, and its schematic configuration will be described with reference to FIG. Figure 10
FIG. 3 is a block diagram of a drive circuit of an image forming apparatus as an example of displaying according to an NTSC television signal. Figure 10
In the above, 101 is the display panel, and 10
2 is a scanning circuit, 103 is a control circuit, 104 is a shift register, 105 is a line memory, 106 is a sync signal separation circuit, 107 is a modulation signal generator, and Vx and Va are DC voltage sources.

The function of each unit will be described below. First, the display panel 101 is connected to an external electric circuit via the terminals Dox1 to Doxm, the terminals Doy1 to Doyn, and the high-voltage terminal Hv. Of these, terminal D
In ox1 to Doxm, scanning for sequentially driving the electron sources provided in the display panel, that is, electron-emitting device groups matrix-wired in a matrix of M rows and N columns row by row (N elements). A signal is applied. On the other hand, terminal D
A modulation signal for controlling the output electron beam of each element of the electron-emitting devices of one row selected by the scanning signal is applied to oy1 to Doyn. Also, the high voltage terminal Hv
Is supplied with a direct current voltage of, for example, 10 K [V] from a direct current voltage source Va, which supplies sufficient energy to excite the phosphor to the electron beam output from the electron-emitting device. It is the acceleration voltage.

Next, the scanning circuit 102 will be described.
The circuit is provided with M switching elements inside (schematically shown by S1 to Sm in the figure), and each switching element is the output voltage of the DC voltage source Vx or 0 [V] (ground). One of the levels) is selected and electrically connected to the terminals Dox1 to Doxm of the display panel 101. Each of the switching elements S1 to Sm has a control signal T output from the control circuit 103.
Although it operates based on the scan, it can actually be easily configured by combining switching elements such as FETs.

In the present embodiment, the direct-current voltage source Vx emits electrons based on the characteristics (electron emission threshold voltage) of the electron-emitting devices, and the drive voltage applied to the non-scanned devices is electron-emitting. It is set to output a constant voltage that is equal to or lower than the threshold voltage.

Further, the control circuit 103 has a function of matching the operations of the respective parts so that an appropriate display is performed based on the image signal inputted from the outside. The synchronization signal Ts sent from the synchronization signal separation circuit 106 described below
Tscan, Tsft for each part based on
And Tmry control signals are generated.

The sync signal separation circuit 106 is a circuit for separating a sync signal component and a luminance signal component from an NTSC television signal input from the outside, and as is well known, frequency separation (filter). It can be easily constructed by using a circuit. The sync signal separated by the sync signal separation circuit 106 is composed of a vertical sync signal and a horizontal sync signal as is well known, but here, for convenience of explanation, it is shown as a Tsync signal. Meanwhile, the luminance signal component of the image separated from the television signal is DAT for convenience.
Although referred to as an A signal, this signal is input to the shift register 104.

The shift register 104 is for serially / parallel converting the DATA signal serially input in time series for each line of the image, and is based on the control signal Tsft sent from the control circuit 103. (That is, the control signal Tsft may be rephrased as the shift clock of the shift register 104). The serial / parallel converted image data for one line (corresponding to driving data for N electron emission elements) is output from the shift register 104 as N parallel signals Id1 to Idn.

The line memory 105 is a storage device for storing data for one line of an image for a required time, and stores the contents of Id1 to Idn as appropriate in accordance with the control signal Tmry sent from the control circuit 103. The stored contents are output as I′d1 to I′dn and input to the modulation signal generator 107.

The modulation signal generator 107 is a signal source for appropriately driving and modulating each of the electron-emitting devices in accordance with each of the image data I'd1 to I'dn, and its output signal is a terminal Doy1. Or through Doyn to be applied to the electron-emitting device in the display panel 101.

As described above, the electron-emitting device according to the present invention has the following basic characteristics with respect to the emission current Ie. That is, as described above, the electron emission has a clear threshold voltage Vth, and the electron emission occurs only when a voltage equal to or higher than Vth is applied.

For a voltage above the electron emission threshold, the emission current also changes according to the change in the voltage applied to the device. Note that the value of the electron emission threshold voltage Vth and the degree of change of the emission current with respect to the applied voltage may change by changing the material, configuration, and manufacturing method of the electron emitting element. You can say something like that.

That is, when a pulsed voltage is applied to this element, for example, when a voltage below the electron emission threshold is applied, no electron emission occurs, but when a voltage above the electron emission threshold is applied. An electron beam is output to. In that case, firstly, it is possible to control the intensity of the output electron beam by changing the peak value Vm of the pulse. Second, it is possible to control the total amount of charges of the electron beam output by changing the pulse width Pw.

Therefore, as the method of modulating the electron-emitting device according to the input signal, there are a voltage modulation method, a pulse width modulation method and the like. In order to implement the voltage modulation method, the modulation signal generator 107 generates a voltage pulse of a constant length, but a circuit of a voltage modulation method that appropriately modulates the peak value of the pulse according to the input data. To use. Further, in order to implement the pulse width modulation method, the modulation signal generator 107 generates a voltage pulse having a constant peak value, but a pulse width that appropriately modulates the width of the voltage pulse according to the input data. A modulation type circuit is used.

Through the series of operations described above, the television can be displayed using the display panel 101. Although not particularly described in the above description, the shift register 104 and the line memory 105 may be of a digital signal type or an analog signal type, and the point is that serial / parallel conversion and storage of image signals are predetermined. It should be done at the speed of.

When the digital signal type is used, it is necessary to convert the output signal DATA of the sync signal separation circuit 106 into a digital signal. This can be easily done by providing an A / D converter at the output section of 106. Needless to say.
Further, in connection with this, it goes without saying that 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 a digital signal,
In the case of the voltage modulation method, for example, a well-known D / A conversion circuit may be used as the modulation signal generator 107, and an amplification circuit or the like may be added if necessary. In the case of the pulse width modulation method, the modulation signal generator 107 compares, for example, a high-speed oscillator and a counter (counter) that counts the number of waves output by the oscillator, and an output value of the counter with an output value of the memory. A person skilled in the art can easily configure the circuit by using a circuit in which a device (comparator) is combined. If necessary, an amplifier for voltage-amplifying the pulse-width-modulated modulation signal output from the comparator to the driving voltage of the electron-emitting device may be added.

On the other hand, in the case of an analog signal, in the case of the voltage modulation method, the modulation signal generator 107 may be an amplifier circuit using a well-known operational amplifier, for example.
You may add a level shift circuit etc. as needed.
In the case of the pulse width modulation method, for example, a well-known voltage control type oscillation circuit (VCO) may be used, and an amplifier for amplifying the voltage up to the driving voltage of the electron-emitting device may be added if necessary. Good.

In the image display device suitable for the present invention completed as described above, the external terminal Dox is attached to each electron-emitting device.
Electrons are emitted by applying a voltage through 1 to Doxm and Doy1 to Doyn, and a high voltage is applied to the metal back 85 or the transparent electrode (not shown) through the high voltage terminal Hv to accelerate the electron beam and collide with the fluorescent film 84. By doing so, an image can be displayed by exciting and emitting the fluorescent film 84.

The above-described structure is a schematic structure necessary for manufacturing a suitable image forming apparatus used for display or the like, and the detailed parts such as the material of each member are not limited to the above contents. , Is appropriately selected to suit the application of the image forming apparatus. Further, although the NTSC system is given as an example of the input signal, the input signal is not limited to this, and PAL, SEC
Various schemes such as an AM scheme may be used, and a TV signal (for example, a high-definition TV such as a MUSE scheme) including a larger number of scanning lines may be used.

Next, an example of the above-mentioned ladder-type electron source, display panel and image forming apparatus will be described with reference to FIGS. 11 and 12.
Will be explained.

In FIG. 11, 110 is an electron source substrate, 1
Reference numeral 11 is an electron-emitting device, and 112 is common wiring Dx1 to Dx10 for wiring the electron-emitting device. A plurality of electron-emitting devices 111 are arranged in parallel in the X direction on the substrate 110 (this is called a device row). A plurality of these element rows are arranged to serve as an electron source. It is possible to independently drive each element row by appropriately applying a drive voltage between the common wirings of each element row. That is, a voltage equal to or higher than the electron emission threshold value may be applied to the element row from which the electron beam is desired to be emitted, and a voltage equal to or lower than the electron emission threshold value may be applied to the element row not to emit the electron beam. Also, the common wiring Dx2 to each element row is
Dx9 may be configured such that, for example, Dx2 and Dx3 have the same wiring.

FIG. 12 shows a display panel of an image forming apparatus provided with the above-mentioned ladder-type electron source. Reference numeral 120 is a grid electrode, 121 is a hole through which electrons pass, 122 is an outer terminal of a container made of Dox1, Dox2 ... Doxm, and 123 is G1 and G connected to the grid electrode 120.
Terminals outside the container made of 2 ... Gn, and 124 are electron source substrates in which the common wiring between the respective element rows is the same wiring as described above. Note that in FIG. 12, the same reference numerals as those in FIGS. 8 and 11 denote the same parts in both figures. A major difference from the image forming apparatus having the simple matrix arrangement (shown in FIG. 8) described above is that the grid electrode 120 is provided between the electron source substrate 110 and the face plate 86.

A grid electrode 120 is provided between the substrate 110 and the face plate 86. The grid electrode 120 is capable of modulating the electron beam emitted from the electron-emitting device, and allows the electron beam to pass through a striped electrode provided orthogonally to the device rows in a ladder-type arrangement. A circular opening 121 is provided for each of the above. The shape and installation position of the grid are not necessarily those shown in FIG. 12, and a large number of passage openings may be provided in a mesh shape as openings, and may be provided around or near the electron-emitting device, for example.

The outside-container terminal 122 and the grid outside-container terminal 123 are electrically connected to a control circuit (not shown).

In the image forming apparatus, the modulation signals for one line of the image are simultaneously applied to the grid electrode columns in synchronization with the sequential driving (scanning) of the element rows one column at a time so that each electron beam Control the irradiation to the phosphor and display the image 1
Can be displayed line by line.

Further, according to the idea of the present invention, an image forming apparatus suitable not only as a display device for television broadcasting but also as a display device for a television conference system, a computer, etc. is provided. Further, it can be used as an image forming apparatus as an optical printer configured by combining with a photosensitive drum or the like. At this time, by appropriately selecting the above-mentioned m row-direction wirings and n column-direction wirings, it can be applied not only as a line-shaped light emitting source but also as a two-dimensional light-emitting source.

[0128]

EXAMPLE 1 An electron-emitting device of the type shown in FIGS. 1A and 1B was produced as the electron-emitting device of this example. A method for manufacturing the electron-emitting device of this embodiment will be described with reference to FIGS. Each symbol in FIGS. 1 and 3 is as described above.

A quartz substrate is used as the insulating substrate 1. After thoroughly cleaning the substrate with an organic solvent, a N substrate is formed on the surface of the substrate 1.
Element electrodes 2 and 3 made of i were formed (FIG. 3A).
At this time, the element electrode interval L is 3 μm, and the element electrode width W is
Was 500 μm and the thickness d was 1000 angstrom.

Using palladium acetate as the organometallic compound, 0.1 mol (22.49 g) of palladium acetate was dissolved in 1000 ml of butyl acetate to obtain a conductive film forming material (coating solution). The coating solution was coated and formed on the insulating substrate 1 on which the element electrodes 2 and 3 were formed under the conditions of 1000 rpm and 30 seconds by a spinner manufactured by Mikasa.

This is heated to 300 ° C. in an oven in an atmosphere of 20% hydrogen sulfide / 80% oxygen to decompose and deposit the organometallic compound on the substrate, and fine particles of palladium sulfide fine particles (average particle diameter: 70 angstrom). A film was formed and used as the conductive film 4 (FIG. 3B). It was confirmed to be palladium sulfide by X-ray analysis. Conductive thin film 4 here
Has a width W ′ of 300 μm and is arranged in the substantially central portion between the device electrodes 2 and 3. The conductive film 4 has a film thickness of 100 Å and a sheet resistance value of 5 × 10 ⁴ Ω.
It was / □. Furthermore, the conductive film 4 obtained in this example
The variation in the sheet resistance value was within 5%.

The fine particle film described here is a film in which a plurality of fine particles are aggregated, and its fine structure is not only a state in which the fine particles are individually dispersed but also a state in which the fine particles are adjacent to each other or overlap each other ( (Including islands), and the particle size refers to the diameter of the fine particles whose particle shape can be recognized in the above state.

Next, as shown in FIG. 3C, the electron-emitting portion 5 is applied with a voltage between the device electrodes 2 and 3 so that the conductive film 4 is formed.
It was manufactured by applying an energization process (forming process) to. The voltage waveform of the energization forming process is shown in FIG.

In FIG. 4, T1 and T2 are the pulse width and pulse interval of the voltage waveform. In this embodiment, T1 is 1 msec.
T2 was 10 msec, the peak value of the triangular wave (peak voltage during forming) was 5 V, and the energization forming treatment was performed for 60 seconds in a vacuum atmosphere of about 1 × 10 ⁻⁶ torr.

The electron-emitting portion 5 thus manufactured
Had a state in which fine particles containing palladium sulfide as a main component were dispersed and arranged, and the average particle size of the fine particles was 30 Å.

The electron emission characteristics of the device manufactured as described above were measured. FIG. 5 shows a schematic configuration diagram of the measurement / evaluation apparatus. Each reference numeral in FIG. 5 is as described above. In this example, the distance between the anode electrode and the electron-emitting device was 4 mm, the potential of the anode electrode was 1 kV,
The degree of vacuum in the vacuum device at the time of measuring electron emission characteristics is 1 × 10 ^-6
It was set to torr.

A device voltage was applied between the electrodes 2 and 3 of the electron-emitting device by using the above measuring and evaluating apparatus, and the device current If and emission current Ie flowing at that time were measured. The current-voltage characteristics as described above were obtained. In the device obtained in this example, the emission current Ie rapidly increased from the device voltage of about 8 V, the device current If was 2.2 mA and the emission current Ie was 1.1 μA at the device voltage of 16 V, and the electron emission efficiency η = Ie / If (%) is 0.05%
Met.

In the embodiment described above, when forming the electron-emitting portion, the triangular wave pulse is applied between the electrodes of the element to perform the forming process, but the waveform applied between the electrodes of the element is limited to the triangular wave. Alternatively, a desired waveform such as a rectangular wave may be used, and the crest value, the pulse width, the pulse interval, etc. are not limited to the above values, and a desired value may be obtained as long as the electron emitting portion is well formed. Can be selected.

Comparative Example 1 An electron-emitting device was produced in the same manner as in Example 1 except that the organometallic compound was heated and fired in the conventional firing atmosphere containing no hydrogen sulfide.

The conductive film 4 obtained in this comparative example is
As a result of X-ray analysis, it was confirmed that the main component was palladium oxide. Further, the variation of the sheet resistance value of the conductive film 4 obtained in this comparative example was 10%.

Example 2 Nickel acetate was used as the organometallic compound, and 0.1 mol (24.88 g) of nickel acetate (tetrahydrate) was added to 10 parts.
It was dissolved in 00 ml of water to obtain a conductive film forming material (coating solution). The coating solution was coated on the insulating substrate 1 on which the device electrodes 2 and 3 were formed under the same conditions as in Example 1 to form a film, which was 350 ° C. in an oven in an atmosphere of 20% hydrogen sulfide / 80% nitrogen. The organometallic compound was decomposed and deposited on the substrate by heating at 0 ° C. to form a fine particle film made of nickel sulfide fine particles (average particle diameter: 70 Å), which was used as the conductive film 4 (FIG. 3B). It was confirmed by X-ray analysis that it was nickel sulfide.

Example 3 In this example, an image forming apparatus was manufactured as follows. A method of manufacturing the electron source of the image forming apparatus of this embodiment will be described with reference to FIGS.

A plan view of a part of the electron source is shown in FIG.
14 is a cross-sectional view taken along the line AA ′ in FIG. 14, and FIGS. 15A to 15D and 16E are cross-sectional views in each step of manufacturing the electron source (cross section AA ′) shown in FIG. 14. )-(H), respectively. In FIGS. 13 to 16, components with the same symbols represent the same components. Here, 71 is an insulating substrate, 72
7 is an X-direction wiring (also referred to as a lower wiring) corresponding to Dxm in FIG. 7, 73 is a Y-direction wiring (also referred to as an upper wiring) corresponding to Dyn in FIG. 7, 4 is a conductive film, 2 and 3 are element electrodes, Reference numeral 141 is an interlayer insulating layer, 142 is a contact hole for electrically connecting the device electrode 2 and the lower wiring 72, 16
1 is a Cr film.

Step-a On a substrate 71 having a 0.5 μm thick silicon oxide film formed on a cleaned blue plate glass by a sputtering method, Cr having a thickness of 50 Å and Au having a thickness of 6000 Å were formed by vacuum evaporation. After sequentially laminating, a photoresist (manufactured by AZ1370 Hoechst) was spin-coated with a spinner, baked, and then exposed and developed with a photomask image.
A resist pattern for the lower wiring 72 is formed, and then Au /
The Cr deposition film was wet-etched to form the lower wiring 72 having a desired shape.

Step-b Next, an interlayer insulating layer 141 made of a silicon oxide film having a thickness of 1.0 μm was deposited by RF sputtering.

Step-c Contact hole 1 is formed in the silicon oxide film deposited in Step b.
A photoresist pattern for forming 42 was formed, and the interlayer insulating layer 141 was etched using this as a mask to form a contact hole 142. Etching is CF ₄
And Reactive Ion using H ₂ gas
Etching) method.

Step-d After that, a pattern to be the device electrodes 2 and 3 and the gap L between the device electrodes is formed into a photoresist (RD-2000N-41).
(Manufactured by Hitachi Chemical Co., Ltd.), and Ti having a thickness of 50 Å and Ni having a thickness of 1000 Å were sequentially deposited by a vacuum deposition method. The photoresist pattern was dissolved in an organic solvent, the Ni / Ti deposition film was lifted off, and element electrodes 2 and 3 having an element electrode interval L of 3 μm and an element electrode width W of 300 μm were formed.

Step-e After the photoresist pattern of the upper wiring 73 is formed on the device electrodes 2 and 3, Ti having a thickness of 50 Å and Au having a thickness of 5000 Å are sequentially deposited by vacuum vapor deposition, and unnecessary by lift-off. By removing the portion, the upper wiring 73 having a desired shape was formed.

Step-f As a pretreatment for forming the conductive film 4, a Cr film 161 having a film thickness of 1000 angstrom is deposited and patterned by vacuum vapor deposition to form a mask having an opening between the element electrode gap L and its vicinity. Formed. Then, the butyl acetate solution of the organometallic compound (palladium acetate) used in Example 1 was spin-coated with a spinner, and heated and baked at 300 ° C. for 10 minutes in the same baking atmosphere as in Example 1. The conductive film 4 thus formed has P as a main element.
It is a thin film composed of fine particles of dS, and its film thickness is 1
00 angstrom, sheet resistance 5 × 10 ⁴ Ω /
It was □. The fine particle film described here is as described above.

Step-g The Cr film 161 and unnecessary portions of the conductive film 4 after firing were etched with an acid etchant to form a desired pattern of the conductive film 4.

Step-h After forming a pattern such that a resist is applied on the portion other than the contact hole 142, a thickness of 50 is formed by vacuum evaporation.
Angstrom Ti and 5000 Angstrom Au were sequentially deposited. Contact holes 142 were filled by removing unnecessary portions by lift-off.

Through the above steps, the lower wiring 72, the interlayer insulating layer 141, the upper wiring 73, the element electrode 2, and the insulating substrate 71 are formed on the insulating substrate 71.
3, the conductive film 4 and the like are formed.

Next, a display panel was constructed using the electron source manufactured as described above. A method of manufacturing the display panel of the image forming apparatus of this embodiment will be described with reference to FIGS. 8 and 9. Each symbol in both figures is as described above.

After fixing the substrate 71 on which a large number of plane type surface conduction electron-emitting devices were manufactured as described above on the rear plate 81, the face plate 86 (fluorescent on the inner surface of the glass substrate 83) was placed 5 mm above the substrate 71. (A film 84 and a metal back 85 are formed) are arranged via a support frame 82, and frit glass is applied to the joint portion of the face plate 86, the support frame 82, and the rear plate 81, and the atmosphere or nitrogen atmosphere is applied. Sealing was performed by baking at 400 ° C. to 500 ° C. for 10 minutes or more (FIG. 8). Further, the frit glass was also used to fix the substrate 71 to the rear plate 81. In FIG. 8, 74 is an electron-emitting device, and 72 and 73 are wirings in the X and Y directions, respectively.

In the case of monochrome, the fluorescent film 84 is composed of only the fluorescent material, but in this embodiment, the fluorescent material has a stripe shape, a black stripe is formed first, and the fluorescent material of each color is applied to the gap. A fluorescent film 84 was produced. A material having graphite as a main component, which is often used as a material for the black stripe, was used, and a slurry method was used as a method for applying the phosphor to the glass substrate 83.

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

The face plate 86 further includes 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 enhance the conductivity of No. 4, but in this embodiment, it was omitted because sufficient conductivity was obtained only with the metal back.

When performing the above-mentioned sealing, in the case of a color, the phosphors of the respective colors and the electron-emitting devices must correspond to each other, so that sufficient alignment was performed.

The atmosphere in the glass container (envelope) completed as described above is exhausted by a vacuum pump through an exhaust pipe (not shown), and after reaching a sufficient degree of vacuum, the external terminal D
A voltage is applied between the electrodes 2 and 3 of the electron-emitting device 74 through ox1 to Doxm and Doy1 to Doyn, and the conductive film 4 is formed.
The electron-emitting portion 5 was manufactured by performing an energization process (forming process) on the. FIG. 4 shows the voltage waveform of the forming process.

In FIG. 4, T1 and T2 are the pulse width and the pulse interval of the voltage waveform. In the present embodiment, T1 is 1 ms,
T2 is 10 msec, the peak value of the triangular wave (peak voltage during forming) is 5 V, and the forming process is about 1 ×.
It was performed for 60 seconds in a vacuum atmosphere of 10 ⁻⁶ torr.

In the electron-emitting portion 5 thus manufactured, fine particles containing palladium sulfide as a main component were dispersed and arranged, and the average particle diameter of the fine particles was 30 Å.

Next, the exhaust pipe (not shown) was welded by heating with a gas burner at a degree of vacuum of about 10 ^-6 torr to seal the envelope.

Finally, a getter process was performed to maintain the degree of vacuum after sealing. Immediately before sealing, a getter placed at a predetermined position (not shown) in the display panel was heated by a heating method such as high frequency heating to form a vapor deposition film. As the getter, one having Ba as a main component was used.

An image display device is formed by using the display panel completed as described above (driving circuit is not shown), and the external terminals Dox1 to Doxm and Doy1 to each electron-emitting device are formed.
Electrons are emitted by applying a scanning signal and a modulation signal from a signal generating means (not shown) through Doyn, and several kV is applied to the metal back 85 through the high voltage terminal Hv.
By applying the above high voltage to accelerate the electron beam, the fluorescent film 84
The image was displayed by colliding with the above to excite and emit the fluorescent film 84.

Further, in order to understand the characteristics of the flat panel type electron-emitting device manufactured in the above-mentioned steps, at the same time, a standard type electron-emitting device shown in FIG. A sample of a different electron-emitting device was prepared, and its electron-emitting characteristic was measured using the above-described measurement / evaluation apparatus of FIG. The measurement conditions of the above sample were as follows: the distance between the anode electrode and the electron-emitting device was 4 mm, the potential of the anode electrode was 1 kV, and the degree of vacuum in the vacuum device at the time of measuring the electron emission characteristics was 1.
It was set to × 10 ^-6 torr.

When a device voltage was applied between the electrodes 2 and 3 and the device current If and the emission current Ie flowing at that time were measured, the current-voltage characteristics as shown in FIG. 6 were obtained.
In the device obtained in this example, the emission current Ie rapidly increased from the device voltage of about 8 V, the device current If was 2.2 mA and the emission current Ie was 1.1 μA at the device voltage of 16 V, and the electron emission efficiency η = Ie / If (%) was 0.05%.

[0167]

In the method for manufacturing an electron-emitting device of the present invention, since the organometallic compound is heated and fired in the firing atmosphere containing hydrogen sulfide, the temperature, oxygen partial pressure, and a trace amount of the redox substance in the heating and firing step. It is possible to obtain a conductive film containing an inorganic metal sulfide as a main component and having a stable composition, without being affected by atmospheric conditions such as the presence of water, the amount of water vapor, and the degree of vacuum. Therefore, it becomes possible to highly uniformize the surface resistance value (sheet resistance value) of the conductive film by producing an electron-emitting device using the method of the present invention described above. The variation can be suppressed within 5%, which is smaller than the conventional range (about 10%).

Therefore, according to the method of the present invention in which the organometallic compound is heated and fired in the firing atmosphere containing hydrogen sulfide, the variation between the electron-emitting devices during forming and electron emission can be made smaller than before. Therefore, it is possible to reduce the defective product generation rate due to the uneven brightness and the defect of the electron emitting portion in the electron source, the display panel and the image forming apparatus using the same.

[Brief description of drawings]

FIG. 1 (a) is a schematic plan view showing the structure of a basic planar electron-emitting device suitable for the present invention, and FIG. 1 (b) is a sectional view thereof.

FIG. 2 is a schematic cross-sectional view showing the structure of a basic vertical electron-emitting device suitable for the present invention.

FIG. 3 is a schematic cross-sectional view showing an example of a method for manufacturing an electron-emitting device of the present invention.

FIG. 4 is a graph showing an example of a voltage waveform at the time of energization forming processing suitable for the present invention.

FIG. 5 is a schematic configuration diagram of a measurement / evaluation apparatus for measuring electron emission characteristics.

FIG. 6 is a graph showing a typical example of the relationship between the emission current Ie and the device current If and the device voltage Vf of the electron-emitting device manufactured by the manufacturing method of the present invention.

FIG. 7 is a schematic configuration diagram of an electron source having a simple matrix arrangement suitable for the present invention.

FIG. 8 is a schematic configuration diagram of a display panel suitable for the present invention using an electron source having a simple matrix arrangement.

FIG. 9 is a pattern diagram showing an example of a fluorescent film.

FIG. 10 is a block diagram of a drive circuit of an example in which an image forming apparatus suitable for the present invention performs display according to an NTSC television signal.

FIG. 11 is a schematic configuration diagram of a ladder-arranged electron source suitable for the present invention.

FIG. 12 is a schematic configuration diagram of a display panel suitable for the present invention using an electron source arranged in a ladder.

FIG. 13 is a partial plan view of an electron source according to the present invention manufactured in an example.

14 is a cross-sectional view of the electron source of FIG. 13 taken along the line AA ′ in FIG.

15A to 15D are cross-sectional views in respective steps (a to d) of manufacturing the electron source (cross section AA ′) shown in FIG.

16 (e) to 16 (h) are cross-sectional views in each step (e to h) of producing the electron source (cross section AA ′) shown in FIG.

FIG. 17 is a schematic plan view showing a typical configuration of a conventional electron-emitting device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1: Substrate, 2, 3: Element electrode, 4: Conductive film, 5: Electron emission part, 21: Step difference forming part, 31: Droplet applying means, 3
2: Droplet, 50: Ammeter for measuring the device current If flowing through the conductive film 4 between the device electrodes 2, 3, 51: power supply for applying the device voltage Vf to the electron-emitting device, 52: device Ammeter for measuring the emission current Ie emitted from the electron emission portion 5 of the device, 53: high-voltage power supply for applying a voltage to the anode electrode 54, 54: emission current Ie emitted from the electron emission portion 5 of the device An anode electrode for capturing
55: vacuum device, 56: exhaust pump, 71: electron source substrate, 72: X-direction wiring, 73: Y-direction wiring, 74: electron-emitting device, 75: connection, 81: rear plate, 82: support frame, 83: Glass substrate, 84: fluorescent film, 85: metal back, 86: face plate, 87: high voltage terminal, 8
8: envelope, 91: black conductive material, 92: phosphor, 10
1: display panel, 102: scanning circuit, 103: control circuit, 104: shift register, 105: line memory,
106: synchronization signal separation circuit, 107: modulation signal generator,
Vx and Va: DC voltage source, 110: electron source substrate, 1
11: electron-emitting device, 112: Dx1 to Dx10 are common wiring for wiring the electron-emitting device 111, 120: grid electrode, 121: holes through which electrons pass, 12
2: Dox1, Dox2 ... Doxm outer terminal of container, 123: G1 connected to grid electrode 120,
G2 ... Gn outer terminal, 124: electron source substrate, 141: interlayer insulating layer, 142: contact hole,
161: Cr film.

Claims (7)

[Claims] 1. A method of manufacturing an electron-emitting device having a conductive film having an electron-emitting portion formed between electrodes, wherein a step of forming a conductive film having an electron-emitting portion is provided on a substrate. And a step of heating a conductive film forming material containing an organometallic compound as a main component in an atmosphere containing hydrogen sulfide in an amount of at least 10 times the molar amount of the metal in the organometallic compound. And a method for manufacturing an electron-emitting device. 2. A method of manufacturing an electron-emitting device, comprising the step of subjecting the conductive film formed in the step of claim 1 to a forming process for forming an electron-emitting portion. 3. The method of manufacturing an electron-emitting device according to claim 2, wherein the forming process includes a step of energizing the conductive film. 4. The method for manufacturing an electron-emitting device according to claim 1, wherein the electron-emitting device is a surface conduction electron-emitting device. 5. A method of manufacturing an electron source comprising an electron-emitting device and a voltage applying means for the device, wherein the electron-emitting device is manufactured by the method according to any one of claims 1 to 4. And a method of manufacturing an electron source. 6. A method of manufacturing a display panel, comprising an electron source having an electron-emitting device and means for applying a voltage to the device, and a fluorescent film which emits light upon receiving electrons emitted from the device, A method for manufacturing a display panel, characterized in that the electron-emitting device is manufactured by the method according to claim 1. 7. An electron source comprising an electron-emitting device and a voltage applying means for the device, a fluorescent film emitting light upon receiving electrons emitted from the device, and a voltage applied to the device based on an external signal. 5. A method of manufacturing an image forming apparatus, comprising: a drive circuit for controlling the electron emission device, wherein the electron-emitting device comprises:
An image forming apparatus manufacturing method characterized by being manufactured by any one of the methods.