JP3294487B2 - Method of manufacturing electron-emitting device, and method of manufacturing electron source, display panel, and image forming apparatus using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an electron-emitting device in which a voltage is applied to a conductive thin film including an electron-emitting portion provided between opposing electrodes to emit electrons, and an electron-emitting device using the same. , An electron source, a display panel, and an image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, two types of electron-emitting devices using a thermionic electron-emitting device and a cold-cathode electron-emitting device have been known. The cold cathode electron-emitting devices include a field emission type (hereinafter, referred to as “FE type”), a metal / insulating layer / metal type (hereinafter, referred to as “MIM type”), and a surface conduction type electron-emitting device. As an example of the FE type, W. P. Dy
ke & W. W. Dolan, "Field emiss
ion ", Advance in Electron
Physics, 8, 89 (1956) or C.I.
A. Spindt, “PHYSICAL Proper
ties of thin-film field e
mission cathodes with mol
ybdenium cones ", J. Appl. Ph.
ys. , 47, 5248 (1976).

As an example of the MIM type, C.I. A. Mead,
“Operation of Tunnel-Emis
Sion Devices ", J. Apply. Phys.
s. , 32, 646 (1961).

As an example of the surface conduction electron-emitting device,
M. I. Elinson, RadioEng. Elec
Tron Phys. , 10, 1290 (1965).

[0005] The surface conduction electron-emitting device utilizes a phenomenon in which an electron is emitted when a current flows in a small-area thin film formed on a substrate in parallel with the film surface. Examples of the surface conduction electron-emitting device include a device using an SnO ₂ thin film by Elinson et al. And a device using an Au thin film [G. Dittmer: “Thin Solid Fi
lms ", 9,317 (1972)] , In 2 O 3 / S
nO ₂ thin film [M. Hartwell and
C. G. FIG. Fonstad: "IEEE Trans.
ED Conf. , 519 (1975)], using a carbon thin film [Hisashi Araki et al .: Vacuum, Vol. 26, No. 1,
No. 22, p. 22 (1983)].

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

Conventionally, in these surface-conduction electron-emitting devices, the electron-emitting portion 5 is formed by applying a current to the conductive thin film 4 before forming the electron-emitting device by an energizing process called a forming process.
It was common to form That is, the forming process is to apply a DC voltage or a very slowly increasing voltage (for example, about 1 V / min) to both ends of the conductive thin film 4 to energize the conductive thin film 4 to locally destroy, deform or alter the conductive thin film, The purpose is to form the electron-emitting portion 5 in a state of high resistance. In the electron emitting portion 5, a crack is generated in a part of the conductive thin film 4, and electrons are emitted from the vicinity of the crack. The surface-conduction type electron-emitting device that has been subjected to the forming process is configured to apply a voltage to the conductive thin film 4 and cause a current to flow through the device, thereby causing the electron-emitting portion 5 to emit electrons.

[0008]

However, in the conventional method for manufacturing an electron-emitting device, it is difficult to form the device on a large-area substrate, and the manufacturing cost is high.

Further, since the applied droplets have a film thickness distribution, a uniform thin film cannot be obtained, and it becomes difficult to uniformly control a crack state obtained by the forming process.
Good electron emission efficiency could not be obtained.

An object of the present invention is to solve the disadvantages of the conventional method of manufacturing an electron-emitting device, that the device is formed on a large-area substrate and that the manufacturing cost is high. And to provide a good method for manufacturing an electron-emitting device, an electron source, a display panel, and an image forming apparatus.

[0011]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventor has solved the above problem by using a substrate having irregularities as a substrate for manufacturing an electron-emitting device. The present invention that can be solved has been completed.

Namely method of manufacturing an electron-emitting device of the present invention, engineering of a conductive thin film-forming material containing a metal composition imparted in the form of droplets by an inkjet method between opposing electrodes on the substrate, heated baking In the manufacturing method for forming an electron-emitting device through a process, the substrate is provided at a position where the droplet is applied.
And it is characterized in that it have a uneven.

As described above, in the present invention, by using a substrate having irregularities, the thickness of the conductive thin film can be made uniform, and the electron-emitting device, the electron source, the display panel, and the image forming device having good electron-emitting characteristics can be obtained. Equipment can be manufactured.

The present invention also includes a method for manufacturing an electron source, a display panel, and an image forming apparatus.

The method of manufacturing an electron source according to the present invention is a method of manufacturing an electron source comprising an electron-emitting device and a means for applying a voltage to the device, wherein the electron-emitting device is manufactured according to the present invention. It is characterized by being manufactured by a method.

According to a method of manufacturing a display panel of the present invention, an electron source including an electron-emitting device and a means for applying a voltage to the device is provided.
A method for manufacturing a display panel, comprising: a light-emitting body that emits light by receiving electrons emitted from the element, wherein the electron-emitting element is manufactured by the method for manufacturing an electron-emitting element according to the present invention. Things.

According to a method of manufacturing an image forming apparatus of the present invention, there is provided an electron source including an electron-emitting device and a means for applying a voltage to the device, a luminous body that receives and emits electrons emitted from the device, and an external signal. And a drive circuit for controlling a voltage applied to the element based on the method of manufacturing the image forming apparatus, wherein the electron-emitting device is manufactured by the method of manufacturing an electron-emitting device of the present invention. It is assumed that.

Hereinafter, the present invention will be described in more detail.

The substrate having irregularities used in the present invention has irregularities of about 1 to 100 nm formed on the substrate surface, and a method such as ion irradiation or chemical etching is used as a method of forming the irregularities.

The means for applying the metal composition solution to the substrate may be any method as long as it is possible to form and apply droplets. In particular, minute droplets can be efficiently generated with appropriate accuracy. An ink jet system with good controllability and good controllability is convenient. Ink jet systems include those that generate and apply droplets by a mechanical impact such as a piezo element, and bubble jet systems that generate and apply liquid droplets by heating the liquid with a micro heater or the like and bumping it. Microdroplets of about to several tens μg can be generated with good reproducibility and applied to the substrate.

The metal composition solution applied to the substrate by the above means is dried and fired to form an inorganic fine particle film for emitting electrons on the substrate. Note that the fine particle film described here is a film in which a plurality of fine particles are aggregated, and not only in a state where the fine particles are individually dispersed and arranged microscopically, but also in a state where the fine particles are adjacent to each other or overlap each other (including an island shape). Point the membrane. The particle diameter of the fine particle film means the diameter of the fine particles whose particle shape can be recognized in the above state.

In the drying step, natural drying, blast drying, heat drying and the like may be used. The baking step may use a commonly used heating means. The drying step and the baking step do not necessarily have to be performed as separate and distinct steps, and may be performed continuously and simultaneously.

FIG. 2 is a schematic view showing the structure of a surface conduction electron-emitting device to which the present invention can be applied. FIG. 2 (a) is a plan view and FIG. 2 (b) is a sectional view.

In FIG. 2, 1 is a substrate, 2 and 3 are device electrodes, 4 is a conductive thin film, and 5 is an electron emitting portion.

Examples of the substrate 1 include quartz glass, glass having a reduced impurity content such as Na, blue plate glass, a glass substrate obtained by laminating SiO ₂ on a blue plate glass by sputtering or the like, ceramics such as alumina, and a Si substrate. However, the present invention is not limited only to these.

As means for forming the unevenness of the substrate 1,
Examples include ion irradiation and chemical etching, but the present invention is not limited to these.

The locations where the irregularities of the substrate 1 are formed include the entire substrate, the entire substrate surface, a part of the substrate surface, and the like, but the present invention is not limited thereto.

Regarding the size of the unevenness of the substrate 1,
The range is 1 to 100 nm, but the present invention is not limited only to these.

The materials of the opposing device electrodes 2 and 3 are as follows.
General conductor materials can be used. This includes, for example, Ni, Cr, Au, Mo, W, Pt, Ti, Al, C
metals or alloys such as u, Pd and Pd, Ag, Au, R
It can be appropriately selected from a printed conductor made of a metal such as uO ₂ or Pd-Ag or a metal oxide and glass, a transparent conductor such as In ₂ O ₃ —SnO _2, a semiconductor material such as polysilicon, or the like. it can. The element electrode interval L1, the element electrode length W1, the shape of the conductive thin film 4, and the like are designed in consideration of the applied form and the like. The element electrode interval L1 can be preferably in the range of several thousand Angstroms to several hundred micrometers, and more preferably several micrometer to several tens micrometer in consideration of the voltage applied between the element electrodes. Range.

The element electrode length W1 can be in the range of several micrometers to several hundred micrometers in consideration of the resistance value of the electrode and the electron emission characteristics. Device electrode 2,
The thickness d of 3 can be in the range of hundreds of angstroms to several micrometers.

In addition to the configuration shown in FIG.
A configuration in which the conductive thin film 4 and the opposing device electrodes 2 and 3 are laminated on the above in this order can also be adopted. It is preferable to use a fine particle film composed of fine particles for the conductive thin film 4 in order to obtain good electron emission characteristics. The film thickness is determined by the step coverage of the device electrodes 2 and 3 and the device electrodes 2 and 3. In consideration of the resistance value between and the forming processing conditions described later,
Although it is set appropriately, it is usually preferable to set the range from several angstroms to several thousand angstroms, more preferably from 10 angstroms to 500 angstroms. Its resistance, R _S is 10
Is a value in the range of 2 to 10 7 ohms. Note that R _S is
The resistance R of a thin film having a thickness t, a width w, and a length 1 is represented by R = R
Appears when the user enters _S (l / w).

In the specification of the present application, the forming process will be described by taking an energizing process as an example. However, the forming process is not limited to this, and a process of forming a crack in a film to form a high resistance state is performed. Includes

The material constituting the conductive thin film 4 is Pd, P
t, Ru, Ag, Au, Ti, In, Cu, Cr, F
e, metal such as Zn, Sn, Ta, W, Pb, PdO, S
It is appropriately selected from metal oxides such as nO ₂ , In ₂ O ₃ , PbO, and Sb ₂ O ₃ . The fine particle film described here is a film in which a plurality of fine particles are aggregated, and has a fine structure in a state in which the fine particles are dispersed and arranged here or in a state in which the fine particles are adjacent to each other or overlapped (some fine particles are gathered, (Including the case where an island structure is formed as a whole). The particle size of the fine particles ranges from several Angstroms to several thousand Angstroms, preferably 1 Å.
It ranges from 0 ° to 200 °.

In the present specification, the term “fine particles” is frequently used, and the meaning will be described.

Small particles are called "fine particles", and smaller ones are called "ultra fine particles". It is widely practiced to call a “cluster” smaller than “ultrafine particles” and having a few hundred atoms or less.

However, each boundary is not strict, and changes depending on what kind of property is focused on. Further, “fine particles” and “ultrafine particles” may be collectively referred to as “fine particles”, and the description in this specification is in line with this.

"Experimental Physics Course 14 Surface / Particle"
(Edited by Kinoshita Yoshio, Kyoritsu Shuppan published September 1, 1986)
Then, it is described as follows.

In the present description, "fine particles have a diameter of about 2 to 3 μm to about 10 nm. In particular, ultrafine particles have a particle diameter of about 10 nm to 2 to 3 nm.
It means up to about nm. It is not exactly strict because both are collectively written as fine particles, but it is a rough guide. When the number of atoms constituting a particle is two to several tens to several hundreds, it is called a cluster. (P. 195, lines 22-26) In addition, the definition of “ultrafine particles” in the “Hayashi / Ultrafine Particle Project” of the New Technology Development Corporation has a lower minimum particle size. there were.

In the “Ultrafine Particle Project” of the Creative Science and Technology Promotion System (1981 to 1986), a particle having a particle size (diameter) in the range of about 1 to 100 nm is called “ultrafine particle”. Then, one ultrafine particle is about 100-
It is an aggregate of about 10 8 power atoms. Ultra-fine particles are large to giant particles on an atomic scale. "
("Ultrafine Particles-Creative Science and Technology-" Hayashi Tax, edited by Ryuji Ueda and Akira Tazaki; Mita Publishing, 1988, page 2, lines 1 to 4) "Even smaller than ultrafine particles, that is, several to several hundred atoms. A single structured particle is usually called a cluster. ”(Page 12, lines 13 to 13 of the same book) Based on the general term as described above, the term“ fine particles ”in this specification refers to a large number of atoms. The lower limit of the particle size is about several angstroms to about 10 angstroms, and the upper limit is about several microns.

The electron-emitting portion 5 is constituted by a high-resistance crack formed in a part of the conductive thin film 4, and depends on the thickness, film quality, material, and method of forming processing described later of the conductive thin film 4. It will be. Inside the electron emission unit 5,
In some cases, conductive fine particles having a particle size in the range of several angstroms to several hundred angstroms depend. The conductive fine particles are part of the elements of the material constituting the conductive thin film 4,
Alternatively, it contains all elements. The electron emitting portion 5 and the conductive thin film 4 in the vicinity thereof can also contain carbon and a carbon compound.

Hereinafter, an example of the manufacturing method will be described with reference to FIG. 3, the same parts as those shown in FIG. 2 are denoted by the same reference numerals as those shown in FIG.

1) The substrate 1 is sufficiently washed with a detergent, pure water, an organic solvent, or the like, and after forming irregularities on the substrate 1 by ion irradiation, chemical etching, or the like, the device electrode material is formed by a vacuum deposition method, a sputtering method, or the like. Then, device electrodes 2 and 3 are formed on the substrate 1 by, for example, a photolithography technique (FIG. 3A).

2) An organic metal solution (a material for forming a conductive thin film) is dropped between the electrodes on the substrate 1 provided with the device electrodes 2 and 3 with an ink jet device 31 to form an organic metal thin film 6 {FIG. c)｝. As the organometallic solution, a solution of an organometallic compound containing a metal of the material of the conductive thin film 4 as a main element can be used. Next, the organic metal thin film is dried and baked to form a conductive thin film 4 (FIG. 3D).

3) Subsequently, a forming step is performed.
As an example of a method of the forming step, a method by an energization process will be described. When current is applied between the device electrodes 2 and 3 using a power supply (not shown), an electron-emitting portion 5 having a changed structure is formed at the portion of the conductive thin film 4 (FIG. 3D). According to the forming process, a portion where the structure of the conductive thin film 4 is locally broken, deformed or altered is formed. This portion constitutes the electron emission section 5. FIG. 4 shows an example of the voltage waveform of the forming process.

The voltage waveform is preferably a pulse waveform. This includes the method shown in FIG. 4 in which a pulse with a constant pulse peak value is applied continuously and the method shown in FIG. 4B in which a voltage pulse is applied while increasing the pulse peak value.

T1 and T2 in FIG. 4A are the pulse width and pulse interval of the voltage waveform. Usually, T1 is set in the range of 1 microsecond to 10 milliseconds, and T2 is set in the range of 10 microseconds to 100 milliseconds. The peak value of the triangular wave (peak voltage at the time of the forming process) is appropriately selected according to the form of the surface conduction electron-emitting device. Under such conditions, for example, a voltage is applied for several seconds to several tens minutes. The pulse waveform is not limited to a triangular wave, and a desired waveform such as a rectangular wave can be adopted.

T1 and T2 in FIG.
It can be similar to that shown in FIG. The peak value of the triangular wave (the peak voltage at the time of the forming process) can be increased, for example, by about 0.1 V steps.

The end of the forming process is determined by the pulse interval T
2, a voltage that does not locally destroy or deform the conductive thin film 4 is applied, and the current can be measured and detected. For example, an element current flowing by applying a voltage of about 0.1 V is measured, and a resistance value is calculated. When the resistance value indicates 1 M ohm or more, the forming process is terminated.

4) It is preferable to perform a process called an activation process on the device after the forming process. The activation step means that the element current If, the emission current Ie
Is a step that changes significantly. The activation step can be performed, for example, by repeating application of a pulse in an atmosphere containing an organic substance gas, similarly to the forming treatment. This atmosphere can be formed by using an organic gas remaining in the atmosphere when the inside of the vacuum vessel is evacuated using, for example, an oil diffusion pump or a rotary pump, or a vacuum once sufficiently evacuated by an ion pump or the like. It can also be obtained by introducing a gas of an appropriate organic substance therein.

The preferable gas pressure of the organic substance at this time is:
Since it differs depending on the above-described application form, the shape of the vacuum container, the type of the organic substance, and the like, it is appropriately set according to the case. Suitable organic substances include alkanes, alkenes, aliphatic hydrocarbons of alkynes, aromatic hydrocarbons, alcohols,
Aldehydes, ketones, amines, phenol, carboxyl, organic acids such as sulfonic acid and the like,
Specifically, C _n H _{2n + 2} such as methane, ethane, and propane
C such as saturated hydrocarbon, ethylene, propylene represented by
_n H _2n unsaturated hydrocarbon expressed by a composition formula such as, benzene, toluene, methanol, ethanol, formaldehyde, acetaldehyde, acetone, methyl ethyl ketone, methylamine, ethylamine, phenol, formic acid,
Acetic acid, propionic acid and the like can be used. With this process,
Carbon or a carbon compound is deposited on the device from the organic substance existing in the atmosphere, and the device current If and the emission current Ie
Changes significantly.

The end of the activation step is determined as appropriate while measuring the device current If and the emission current Ie. The pulse width, pulse interval, pulse crest value, and the like are set as appropriate.

Carbon and carbon compounds include graphite (HOPG including HOPG, PG and GC).
Indicates a crystal structure of almost perfect graphite, PG indicates a crystal grain of about 200 ° and has a slightly disordered crystal structure, and GC indicates a crystal grain of about 20 ° and has a further disordered crystal structure. ), Amorphous carbon (refers to amorphous carbon and a mixture of amorphous carbon and the microcrystals of graphite), and has a thickness of 500
Å It is preferable to set the following range.

5) The electron-emitting device obtained through such a step is preferably subjected to a stabilization step. This step is a step of exhausting the organic substance in the vacuum vessel. It is preferable to use a vacuum exhaust device that does not use oil so that the oil generated from the device does not affect the characteristics of the element. Specifically, a vacuum exhaust device such as a sorption pump or an ion pump can be used.

In the activation step, when an oil diffusion pump is used as an exhaust device and an organic gas derived from an oil component generated from the oil diffusion pump is used, the partial pressure of this component needs to be kept as low as possible. The partial pressure of the organic component in the vacuum vessel is preferably a partial pressure at which the above-mentioned carbon and carbon compounds are hardly newly deposited, and is preferably 1 × 10 −8 Torr or less, and more preferably 1 × 10 −10 Torr or less. Particularly preferred. Further, when evacuating the inside of the vacuum vessel, it is preferable to heat the entire vacuum vessel to facilitate evacuating the organic substance molecules adsorbed on the inner wall of the vacuum vessel and the electron-emitting device. The heating condition at this time is preferably 80 to 200 ° C. for 5 hours or more, but is not particularly limited to this condition, and the heating is performed under conditions appropriately selected according to various conditions such as the size and shape of the vacuum vessel and the configuration of the electron-emitting device. .

The pressure in the vacuum vessel needs to be as low as possible, and is preferably 1-3 × 10 −7 Torr or less, more preferably 1 × 10 −8 Torr or less. The atmosphere at the time of driving after performing the stabilization step is preferably the same as the atmosphere at the end of the stabilization treatment, but is not limited thereto. Even if it is slightly reduced, sufficiently stable characteristics can be maintained.

By employing such a vacuum atmosphere, the deposition of new carbon or a carbon compound can be suppressed.
As a result, the element current If and the emission current Ie are stabilized.

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

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

In the vacuum vessel 55, equipment necessary for measurement in a vacuum atmosphere such as a vacuum gauge (not shown) is provided.
Measurement and evaluation can be performed in a desired vacuum atmosphere. The exhaust pump 56 is composed of a normal high vacuum device system including a turbo pump and a rotary pump, and an ultra high vacuum device system including an ion pump and the like. The entire vacuum processing apparatus equipped with the electron source substrate shown here is
It can be heated up to 200 degrees by a heater (not shown). Therefore, when this vacuum processing apparatus is used, steps subsequent to the above-described forming step can also be performed.

FIG. 6 shows emission current Ie, device current If and device voltage Vf measured using the vacuum processing apparatus shown in FIG.
FIG. 5 is a diagram schematically showing the relationship of FIG. In FIG. 6, since the emission current Ie is significantly smaller than the device current If,
Shown in arbitrary units. Note that both the vertical and horizontal axes are linear scales.

As is apparent from FIG. 6, the surface conduction electron-emitting device applicable to the present invention has three characteristic characteristics with respect to the emission current Ie.

(I) When an element voltage Vf of a certain voltage (referred to as a threshold voltage, Vth in FIG. 6) or more is applied to the present element, the emission current Ie sharply increases, while the threshold voltage Vth Below, the emission current Ie is hardly detected. That is, it is a nonlinear element having a clear threshold voltage Vth with respect to the emission current Ie.

(Ii) Since the emission current Ie depends monotonically on the device voltage Vf, the emission current Ie can be controlled by the device voltage Vf.

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

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

In FIG. 6, an example in which the element current If monotonically increases with respect to the element voltage Vf (hereinafter referred to as "MI characteristic") is shown by a solid line. The element current If is equal to the element voltage Vf.
May exhibit a voltage control type negative resistance characteristic (hereinafter, referred to as “VCNR characteristic”) in some cases (not shown). Further, these characteristics can be controlled by controlling the above-described steps.
An application example of the electron-emitting device applicable to the present invention will be described below. By arranging a plurality of surface conduction electron-emitting devices applicable to the present invention on a substrate, for example, an electron source or an image forming apparatus can be configured.

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

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

The surface conduction electron-emitting device to which the present invention can be applied is as described above in (i) to (iii).
There is a characteristic. That is, when the electron emission from the surface conduction electron-emitting device is equal to or higher than the threshold voltage, it can be controlled by the peak value and the width of the pulse voltage applied between the opposing device electrodes. On the other hand, when the voltage is equal to or lower than the threshold voltage, it is hardly emitted. According to this characteristic, even when a large number of electron-emitting devices are arranged, if a pulse-like voltage is appropriately applied to each device,
The electron emission amount can be controlled by selecting the surface conduction electron-emitting device according to the input signal.

Hereinafter, based on this principle, an electron source substrate obtained by disposing a plurality of electron-emitting devices applicable to the present invention will be described with reference to FIG. In FIG. 7, reference numeral 71 denotes an electron source substrate, 72 denotes an X-direction wiring, and 73 denotes a Y-direction wiring.
74 is a surface conduction electron-emitting device, and 75 is a connection.
Incidentally, the surface conduction electron-emitting device 74 may be either the above-mentioned flat type or vertical type.

The m X-direction wirings 72 are DX1, DX2,
... made of DXm, and can be made of a conductive metal or the like formed by a vacuum deposition method, a printing method, a sputtering method, or the like. The material, thickness, and width of the wiring are appropriately set. Y
The directional wiring 73 includes n wirings DY1, DY2,... DYn, and is formed in the same manner as the X-directional wiring 72. An interlayer insulating layer (not shown) is provided between the m X-directional wirings 72 and the n Y-directional wirings 73 to electrically separate them (m and n are both Positive integer).

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

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

[0074] Materials constituting the wiring 72 and the wiring 73, the material constituting the wire connection 75, the material constituting the 及 beauty pair of device electrodes may be part or all of the constituent elements are the same, also different from each other Is also good. These materials are appropriately selected, for example, from the above-described materials for the device electrodes. When the material forming the element electrode is the same as the wiring material, the wiring connected to the element electrode can also be called an element electrode. X
The direction wiring 72 is connected to a scanning signal applying unit (not shown) for applying a scanning signal for selecting a row of the surface conduction electron-emitting devices 74 arranged in the X direction. On the other hand, the Y-direction wiring 7
3, a modulation signal generating means (not shown) for modulating each row of the surface conduction electron-emitting devices 74 arranged in the Y direction according to an input signal is connected. The driving voltage applied to each electron-emitting device is supplied as a difference voltage between a scanning signal and a modulation signal applied to the device.

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

An image forming apparatus configured using such an electron source having a simple matrix arrangement will be described with reference to FIGS. 8, 9 and 10. FIG. FIG. 8 is a schematic view showing an example of a display panel of the image forming apparatus, and FIG. 9 is a schematic view of a fluorescent film used in the image forming apparatus of FIG. FIG. 10 is a block diagram showing an example of a driving circuit for performing display according to an NTSC television signal.

In FIG. 8, reference numeral 71 denotes an electron source substrate on which a plurality of electron-emitting devices are arranged; 81, a rear plate to which the electron source substrate 71 is fixed; 86, a fluorescent film 84 on the inner surface of a glass substrate 83;
And a face plate on which a metal back 85 and the like are formed. Reference numeral 82 denotes a support frame, to which a rear plate 81 and a face plate 86 are connected using frit glass or the like. Reference numeral 88 denotes an envelope, which is sealed by baking in a temperature range of 400 to 500 ° C. for 10 minutes or more in the atmosphere or nitrogen, for example.

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

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

FIG. 9 is a schematic view showing a fluorescent film. The fluorescent film 84 can be composed of only a phosphor in the case of monochrome. In the case of a color fluorescent film, it can be composed of a black conductive material 91 called a black stripe or a black matrix and a fluorescent material 92 depending on the arrangement of the fluorescent materials. The purpose of providing the black stripes and the black matrix is to make the mixed portions inconspicuous by making the painted portions between the phosphors 92 of the necessary three primary color phosphors black in the case of color display, An object of the present invention is to suppress a decrease in contrast due to light reflection. As a material for the black stripe, a material which is conductive and has little light transmission and reflection can be used in addition to a commonly used material mainly containing graphite.

The method of applying the fluorescent substance to the glass substrate 83 can employ a precipitation method, a printing method, or the like irrespective of monochrome or color. Usually, a metal back 8 is provided on the inner side of the fluorescent film 84.
5 are provided. The purpose of providing the metal back is to improve the brightness by mirror-reflecting the light toward the inner surface side of the phosphor emission toward the face plate 86 side, to act as an electrode for applying an electron beam acceleration voltage, The purpose is to protect the phosphor from damage due to collision of negative ions generated in the envelope. The metal back is
After the formation of the fluorescent film, a smoothing treatment (usually called "filming") of the inner surface of the fluorescent film is performed, and then A1
Can be produced by depositing by vacuum evaporation or the like.

The face plate 86 further has the fluorescent film 8
A transparent electrode (not shown) may be provided on the outer surface side of the fluorescent film 84 in order to increase the conductivity of the phosphor film 84. When performing the above-described sealing, in the case of color, it is necessary to make each color phosphor correspond to the electron-emitting device, and sufficient alignment is indispensable.
The image forming apparatus shown in FIG. 8 is manufactured, for example, as follows.

The envelope 88 is evacuated through an exhaust pipe (not shown) by an exhaust device that does not use oil, such as an ion pump or a sorption pump, while appropriately heating the envelope 88 in the same manner as in the above-described stabilization step. After the atmosphere having a vacuum degree of about 7 Torr and a sufficiently small amount of organic substances is set, sealing is performed. To maintain the degree of vacuum after the envelope 88 is sealed, a getter process may be performed. This is because the getter disposed at a predetermined position (not shown) in the envelope 88 is heated by heating using resistance heating, high-frequency heating, or the like immediately before or after the envelope 88 is sealed. This is a process for forming a deposited film.

The getter is usually composed mainly of Ba or the like, and maintains a vacuum degree of, for example, 1 × 10 -5 or 1 × 10 -7 Torr by the adsorption action of the deposited film. Here, steps after the forming process of the surface conduction electron-emitting device can be appropriately set.

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

The display panel 101 is connected to an external electric circuit via terminals Dox1 to Doxm, terminals Doy1 to Doyn, and a high voltage terminal Hv. Terminal Do
x1 to Doxm are provided for sequentially driving electron sources provided in the display panel, that is, a group of surface conduction electron-emitting devices arranged in a matrix of M rows and N columns, one row (N element) at a time. A scanning signal is applied.

A modulation signal for controlling the output electron beam of each of the surface conduction electron-emitting devices in one row selected by the scanning signal is applied to the terminals Dy1 to Dyn. The high voltage terminal Hv is supplied with a DC voltage of, for example, 10 K [V] from a DC voltage source Va, which is sufficient to excite the phosphor into an electron beam emitted from the surface conduction electron-emitting device. An accelerating voltage for applying energy.

The scanning circuit 102 will be described. This circuit includes M switching elements inside (in the drawing, S1 to Sm are schematically shown). Each switching element selects either the output voltage of the DC voltage source Vx or 0 [V] (ground level),
The display panel 101 is electrically connected to terminals Dx1 to Dxm. Each of the switching elements S1 to Sm is
It operates based on a control signal T _SCAN output by the control circuit 103, and can be configured by combining switching elements such as FETs, for example.

In the case of the present embodiment, the DC voltage source Vx is based on the characteristics (electron emission threshold voltage) of the surface conduction electron-emitting device, and the driving voltage applied to the non-scanned device is the electron emission threshold. It is set to output a constant voltage that is equal to or lower than the value voltage.

The control circuit 103 has a function of matching the operation of each unit so that appropriate display is performed based on an image signal input from the outside. The control circuit 103 generates T _SCAN, T _SFT, and T _MRY control signals for each unit based on the synchronization signal T _SYNC sent from the synchronization signal separation circuit 106.

The synchronizing signal separating circuit 106 is a circuit for separating a synchronizing signal component and a luminance signal component from an NTSC television signal input from the outside, and uses a general frequency separating (filter) circuit or the like. Can be configured. The synchronizing signal separated by the synchronizing signal separating circuit 106 includes a vertical synchronizing signal and a horizontal synchronizing signal. Here, for the sake of convenience, the synchronizing signal is illustrated as a T _SYNC signal. The luminance signal component of the image separated from the television signal is referred to as a DATA signal for convenience. The DATA signal is input to the shift register 104.

The shift register 104 is for serially / parallel converting the DATA signal input serially in time series for each line of an image. The shift register 104 converts the data into a control signal T _SFT sent from the control circuit 103. (Ie, the control signal T _SFT can be said to be a shift clock of the shift register 104).
The data for one line of the serial / parallel-converted image (corresponding to drive data for N electron-emitting devices) is Id
It is output from the shift register 104 as N parallel signals of 1 to Idn.

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

The modulation signal generator 107 is a signal source for appropriately driving and modulating each of the surface motor type electron-emitting devices in accordance with each of the image data Id'1 to Id'n. Is applied to the surface conduction electron-emitting device in the display panel 101 through the terminals Doy1 to Doyn.

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

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

When implementing the pulse width modulation method,
As the modulation signal generator 107, a pulse width modulation type circuit that generates a voltage pulse having a constant peak value and appropriately modulates the width of the voltage pulse according to input data can be used.

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

When the digital signal type is used, it is necessary to convert the output signal DATA of the synchronizing signal separating circuit 106 into a digital signal. This can be achieved by providing an A / D converter at the output of the signal 106. In connection with this, the line memory 105
The circuit used for the modulation signal generator 107 is slightly different depending on whether the output signal is a digital signal or an analog signal. That is, in the case of the voltage modulation method using a digital signal, for example, a D / A conversion circuit is used as the modulation signal generator 107, and an amplification circuit and the like are added as necessary. In the case of the pulse width modulation method, the modulation signal generator 107 includes, for example, a high-speed oscillator, a counter for counting the number of waves output from the oscillator, and a comparison for comparing the output value of the counter with the output value of the memory. The circuit which combined the device (comparator) is used. If necessary, an amplifier for amplifying the voltage of the pulse width modulated signal output from the comparator to the drive voltage of the surface conduction electron-emitting device can be added.

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

In the image display device to which the present invention can be applied, which has such a configuration, the external terminals Dox1 to Doxm, Doy1 to Doy are provided to each electron-emitting device.
By applying a voltage through n, electron emission occurs. A high voltage is applied to the metal back 85 or a transparent electrode (not shown) via the high voltage terminal Hv to accelerate the electron beam. The accelerated electrons collide with the fluorescent film 84 and emit light to form an image.

The configuration of the image forming apparatus described here is an example of an image forming apparatus to which the present invention can be applied, and various modifications can be made based on the technical idea of the present invention. Although the NTSC system has been used as the input signal, the input signal is not limited to the NTSC system. In addition to the PAL and SECAM systems, a TV signal including a larger number of scanning lines (for example, the MUSE system, etc.) High-definition TV).

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

FIG. 11 is a schematic view showing an example of a ladder-type electron source. In FIG. 11, reference numeral 110 denotes an electron source substrate, and 111 denotes an electron-emitting device. 112, Dx1-D
x10 is a common wiring for connecting the electron-emitting devices 111. The electron-emitting device 111 has an X
A plurality are arranged in parallel in the direction (this is called an element row). A plurality of the element rows are arranged to constitute an electron source. By applying a drive voltage between the common wires of each element row, each element row can be driven independently. That is,
A voltage equal to or higher than the electron emission threshold is applied to an element row that wants to emit an electron beam.
A voltage lower than the electron emission threshold is applied. As for the common wirings Dx2 to Dx9 between the element rows, for example, Dx2 and Dx3 can be the same wiring.

FIG. 12 is a schematic diagram showing an example of a panel structure in an image forming apparatus having a ladder-type electron source. 120 is a grid electrode, 121 is a hole through which electrons pass, and 122 is Dox1, Dox2,.
m outside the container. 123 is a grid electrode 1
A terminal outside the container consisting of G1, G2,... Gn connected to 20 is an electron source substrate in which the common wiring between the element rows is the same wiring. In FIG. 11, the same portions as those shown in FIGS. 8 and 11 are denoted by the same reference numerals as those shown in these drawings. The image forming apparatus shown here and FIG.
The major difference from the image forming apparatus of the simple matrix arrangement shown in FIG. 9 is whether or not the grid electrode 120 is provided between the electron source substrate 110 and the face plate 86.

In FIG. 12, a grid electrode 120 is provided between the substrate 110 and the face plate 86. The grid electrode 120 is for modulating the electron beam emitted from the surface conduction electron-emitting device,
One circular opening 121 is provided for each element in order to allow an electron beam to pass through a striped electrode provided orthogonal to the ladder-shaped element rows. The shape and installation position of the grid are not limited to those shown in FIG. For example, a large number of passage openings may be provided in a mesh shape as openings, and a grid may be provided around or near the surface conduction electron-emitting device.

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

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

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

[0110]

EXAMPLE 1 An electron-emitting device of the type shown in FIG. 2 was produced as an electron-emitting device. FIG. 2A is a plan view of the device, and FIG.
Shows a cross-sectional view. 2A and 2B, reference numeral 1 denotes an insulating substrate, 2 and 3 denote a pair of device electrodes for applying a voltage to the device, 4 denotes a conductive thin film, and 5 denotes an electron emitting portion. . In the drawing, L1 represents the element electrode interval, W1 represents the width of the element electrode, d represents the thickness of the element electrode, and W2 represents the width of the thin film.

A method for manufacturing the electron-emitting device of this embodiment will be described with reference to FIG. First, a quartz glass substrate was prepared as the insulating substrate 1, and this was sufficiently washed with an organic solvent.
Next, a gun voltage of 3 kV and a gun current of 0.5 mA were applied to this substrate.
Ar ions were irradiated for 30 minutes at an incident angle of 45 °.
At this time, not-shown minute (about 5 nm) irregularities were formed on the substrate surface. Next, device electrodes 2 and 3 made of Ni were formed on the substrate surface {FIG. 3A}. Element electrode interval L
1 was 3 μm, the width W1 of the device electrode was 500 μm, and its thickness d was 1000 °.

An arbitrary amount of an aqueous solution containing 40% by weight of dimethyl sulfoxide was prepared, and palladium acetate was dissolved therein to obtain a palladium weight concentration of 0.4% to obtain a dark red solution. A part of this solution was taken in another container and the pressure was reduced to evaporate the solvent until a reddish brown paste was obtained. Droplets 32 of the above dark red solution (material for forming a conductive thin film) are applied by a bubble jet type ink jet device 31 like a liquid reservoir 33 straddling the electrodes 2 and 3 {FIG.
(B)｝. Next, this organometallic thin film 6 {FIG.
After drying at 0 ° C. for 2 minutes, baking was performed at 350 ° C. for 12 minutes to form a conductive thin film 4 mainly made of palladium oxide (FIG. 3D).

When observed using an optical microscope, no large unevenness in the thickness of the thin film was observed, and a thin film having a substantially uniform thickness was formed.

Next, a voltage was applied between the device electrodes 2 and 3 in a vacuum vessel, and the conductive thin film 4 was subjected to an energizing process (forming process) to form an electron-emitting portion 5 {FIG. )｝. FIG. 4 shows a voltage waveform of the forming process.

In this embodiment, the pulse width T1 of the voltage waveform is set to 1
Milliseconds, the pulse interval T2 is 10 milliseconds, the peak value of the triangular wave (peak voltage at the time of forming processing) is 5 V,
Forming process is about 1 × 10 minus 6 torr
For 60 seconds. In the electron-emitting portion 5 thus formed, fine particles mainly containing palladium element were dispersed and arranged, and the average particle size of the fine particles was 50 °.

The electron emission characteristics of the device fabricated as described above were measured by a measurement and evaluation apparatus having the structure shown in FIG. The electron-emitting device and the anode electrode 54 are installed in a vacuum device 55, and the vacuum device 55 has a vacuum device 5 such as an exhaust pump 56 and a vacuum gauge (not shown).
5 is equipped with the necessary equipment so that measurement and evaluation of the present element can be performed under a desired vacuum. In this embodiment, the distance between the anode 54 and the electron-emitting device is 4 m.
m, the potential of the anode electrode 54 is 1 kV, and the degree of vacuum in the vacuum apparatus at the time of measuring the electron emission characteristics is 1 × 10 −6 t.
orr.

By using the above-described measurement and evaluation apparatus, an element voltage is applied between the electrodes 2 and 3 of the electron-emitting device.
When the device current If and the emission current Ie flowing at that time were measured, current-voltage characteristics as shown in FIG. 6 were obtained. In this device, the emission current Ie rapidly increases from a device voltage of about 7 V, and the average device current If
Was 0.8 mA, the emission current Ie was 0.62 μA, and the electron emission efficiency η = Ie / If (%) was 0.08%.

The variation in the electron emission efficiency of the device is 1
5%. In the above-described embodiment, when forming an electron emission portion, a forming process is performed by applying a triangular wave pulse between the electrodes of the device. The waveform applied in between is not limited to a triangular wave, and a desired waveform such as a rectangular wave may be used. The peak value, pulse width, pulse interval, and the like are not limited to the values described above, and the electron emitting portion may be used. If formed well, a desired value can be selected.

Example 2 A 30% by weight aqueous solution of dimethyl sulfoxide was prepared, and palladium propionate was added to the aqueous solution at a palladium weight concentration of 0.1%.
It was dissolved to 25% to obtain a red solution. Less than,
An electron-emitting device was prepared in the same manner as in the first embodiment.
It was confirmed that the same electron emission efficiency and the same variation in electron emission efficiency were obtained.

Example 3 In the same manner as in Example 1, an organometallic compound solution droplet 32 was applied to each counter electrode of a substrate (FIG. 7) on which a plurality of device electrodes and matrix wirings were formed by a bubble jet method. After being applied and dried and heated and baked by the ink jet device 31, the electron source substrate 71 is subjected to a forming process.
And The rear plate 81, the support frame 82, and the face plate 86 were connected to the electron source substrate 71 and vacuum-sealed to produce a display panel according to the conceptual diagram of FIG.

Example 4 An electron-emitting device of the type shown in FIG. 2 was prepared as an electron-emitting device.

A method for manufacturing the electron-emitting device of this embodiment will be described with reference to FIG. First, a quartz glass substrate was prepared as the insulating substrate 1, and this was sufficiently washed with an organic solvent.
Next, the substrate was immersed in a 0.05% by weight aqueous solution of hydrogen fluoride at room temperature for 5 minutes, taken out, washed with water, and further thoroughly washed with an organic solvent. At this time, not-shown minute (about 5 nm) irregularities were formed on the substrate surface.

Further, the substrate was sufficiently washed with an organic solvent. Next, device electrodes 2 and 3 made of Ni were formed on the substrate surface {FIG. 3A}. The element electrode interval L1 was 3 μm, the element electrode width W1 was 500 μm, and its thickness d was 1000 °.

An arbitrary amount of an aqueous solution containing 40% by weight of dimethyl sulfoxide was prepared, and palladium acetate was dissolved therein to obtain a palladium weight concentration of 0.4% to obtain a dark red solution. A part of this solution was taken in another container and the pressure was reduced to evaporate the solvent until a reddish brown paste was obtained. Droplets 32 of the above dark red solution (material for forming a conductive thin film) are applied by a bubble jet type ink jet device 31 like a liquid reservoir 33 straddling the electrodes 2 and 3 {FIG.
(B)｝. Next, this organometallic thin film 6 {FIG.
After drying at 0 ° C. for 2 minutes, baking was performed at 350 ° C. for 12 minutes to form a conductive thin film 4 mainly made of palladium oxide (FIG. 3D).

When observed using an optical microscope, no unevenness in the thickness of the thin film was observed, and a thin film having a uniform thickness was formed.

Next, a voltage was applied between the device electrodes 2 and 3 in a vacuum vessel, and the conductive thin film 4 was subjected to an energizing process (forming process) to form an electron-emitting portion 5 {FIG. )｝. FIG. 4 shows a voltage waveform of the forming process.

In this embodiment, the pulse width T1 of the voltage waveform is set to 1
The pulse duration T2 was 10 milliseconds, the peak value of the triangular wave (peak voltage at the time of forming) was 5 V, and the forming process was performed in a vacuum atmosphere of about 1 × 10 −6 torr for 60 seconds. The electron-emitting portion 3 thus formed is in a state in which fine particles mainly composed of palladium element are dispersed and arranged, and the average particle diameter of the fine particles is 5.
It was 0 °.

The electron emission characteristics of the device fabricated as described above were measured by a measurement and evaluation apparatus having the structure shown in FIG. The present electron-emitting device and the anode electrode 54 are installed in a vacuum device 55, and the vacuum device 55 is provided with equipment necessary for a vacuum device such as an exhaust pump 56 and a vacuum gauge (not shown). The device can be measured and evaluated under vacuum. In this embodiment, the distance between the anode 54 and the electron-emitting device is 4 m.
m, the potential of the anode electrode 54 is 1 kV, and the degree of vacuum in the vacuum device 55 at the time of measuring electron emission characteristics is 1 × 10 minus 6
The power was torr.

Using the above-described measurement and evaluation apparatus, a device voltage is applied between the electrodes 2 and 3 of the electron-emitting device.
When the device current If and the emission current Ie flowing at that time were measured, current-voltage characteristics as shown in FIG. 6 were obtained. In this device, the emission current Ie rapidly increases from an element voltage of about 7 V. At an element voltage of 12 V, the element current If becomes 1.0 mA, the emission current Ie becomes 0.8 μA, and the electron emission efficiency η = Ie / If (%). Was 0.08%.

The variation in the electron emission efficiency for each device was 15%. (Note that there are 10 elements on the substrate.) In the above-described embodiment, when forming an electron-emitting portion, a forming process is performed by applying a triangular wave pulse between the electrodes of the element. The waveform to be applied in between is not limited to a triangular wave, and a desired waveform such as a rectangular wave may be used. The peak value, pulse width, pulse interval, and the like are not limited to the values described above. If formed well, a desired value can be selected.

Example 5 A 30% by weight aqueous solution of dimethyl sulfoxide was prepared, and palladium propionate was added to the aqueous solution at a palladium weight concentration of 0.1%.
It was dissolved to 25% to obtain a red solution. Less than,
An electron-emitting device was prepared in the same manner as in the fourth embodiment.
It was confirmed that the same electron emission efficiency and the same variation in electron emission efficiency were obtained.

Example 6 In the same manner as in Example 4, an organometallic compound solution droplet 32 was applied to each counter electrode of a substrate (FIG. 7) on which a plurality of device electrodes and matrix wirings were formed by a bubble jet method. After being applied and baked by the ink jet device 31, a forming process was performed to obtain an electron source substrate. A rear plate 81, a support frame 82, and a face plate 86 were connected to the electron source substrate and vacuum-sealed to produce a display panel according to the conceptual diagram of FIG.

Comparative Example 1 An electron-emitting device of the type shown in FIG. 2 was prepared as an electron-emitting device.

A method for manufacturing the electron-emitting device of this comparative example will be described with reference to FIG. First, a quartz glass substrate was prepared as the insulating substrate 1, and this was sufficiently washed with an organic solvent, and then the device electrodes 2 and 3 made of Ni were formed on the substrate surface.
(A)｝. The element electrode interval L1 was 3 μm, the element electrode width W1 was 500 μm, and its thickness d was 1000 °.

An arbitrary amount of an aqueous solution containing 40% by weight of dimethyl sulfoxide was prepared, and palladium acetate was dissolved therein to obtain a palladium weight concentration of 0.4% to obtain a dark red solution. A part of this solution was taken in another container and the pressure was reduced to evaporate the solvent until a reddish brown paste was obtained. Droplets 32 of the above dark red solution (material for forming a conductive thin film) are applied by a bubble jet type ink jet device 31 like a liquid reservoir 33 straddling the electrodes 2 and 3 {FIG.
(B)｝. Next, this organometallic thin film 6 {FIG.
After drying at 0 ° C. for 2 minutes, it was baked at 350 ° C. for 12 minutes to form a conductive thin film 4 mainly composed of palladium oxide {FIG. 3 (d)}.

Next, a voltage was applied between the device electrodes 2 and 3 in a vacuum vessel, and the conductive thin film 4 was energized (formed) to form the electron-emitting portion 5 {FIG. )｝. FIG. 3 shows a voltage waveform of the forming process.

In this comparative example, the pulse width T1 of the voltage waveform is set to 1
The pulse duration T2 was 10 milliseconds, the peak value of the triangular wave (peak voltage at the time of forming) was 5 V, and the forming process was performed in a vacuum atmosphere of about 1 × 10 −6 torr for 60 seconds. The electron-emitting portion 5 thus formed is in a state in which fine particles mainly composed of palladium element are dispersed and arranged, and the average particle diameter of the fine particles is 5
It was 0 °.

With respect to the device fabricated as described above, the electron emission characteristics were measured by the measurement and evaluation apparatus having the configuration shown in FIG. The electron-emitting device and the anode electrode 54 are installed in a vacuum device 55, and the vacuum device 55 has a vacuum device 5 such as an exhaust pump 56 and a vacuum gauge (not shown).
5 is equipped with the necessary equipment so that measurement and evaluation of the present element can be performed under a desired vacuum. In this embodiment, the distance between the anode electrode and the electron-emitting device is 4 mm,
The potential of the anode electrode was 1 kV, and the degree of vacuum in the vacuum apparatus at the time of measuring the electron emission characteristics was 1 × 10 −6 torr.

Using the above-described measurement and evaluation apparatus, a device voltage is applied between the electrodes 2 and 3 of the electron-emitting device.
When the device current If and the emission current Ie flowing at that time were measured, current-voltage characteristics as shown in FIG. 6 were obtained. In this device, the emission current Ie rapidly increases from an element voltage of about 7 V. At an element voltage of 12 V, the element current If becomes 0.8 mA, the emission current Ie becomes 0.62 μA, and the electron emission efficiency η = Ie / If (%). Was 0.08%.

The variation in the electron emission efficiency for each device was 37%. In addition, the variation is the variation of 10 pieces of the above-described elements formed on a substrate. Comparative Example 2 An arbitrary amount of an aqueous solution containing 30% by weight of dimethyl sulfoxide was prepared, and palladium propionate was dissolved in the aqueous solution so as to have a palladium weight concentration of 0.25% to obtain a red solution.
Hereinafter, an electron-emitting device was prepared in the same manner as in Comparative Example 1, and it was confirmed that the same electron-emitting efficiency and variation in electron-emitting efficiency as in Comparative Example 1 were obtained.

[0141]

As described above, if an electron-emitting device is formed according to the method of the present invention, droplets are applied by an ink jet method, so that the film forming process can be simplified without using a large vacuum thin film forming apparatus. The element can be formed over a large area at low cost. Furthermore, if an electron-emitting device is formed according to the present invention, in the step of partially applying a droplet of a solution containing a metal composition to the substrate, since a substrate having irregularities is used and the roughness of the surface is increased, Since the true contact angle of the droplet applied to the substrate is smaller than 90 degrees and the roughness of the surface increases due to the unevenness of the substrate, the apparent contact angle of the droplet decreases, so that the droplet is easily wetted. Since the droplets can be spread evenly, a desired uniform film thickness and desired device characteristics can be easily obtained, so that a favorable electron-emitting device, electron source, display panel, image forming apparatus, etc. A manufacturing method can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic plan view and a configuration diagram showing an example of a conventional surface conduction electron-emitting device.

FIG. 2 is a schematic plan view and a cross-sectional view illustrating an example of a surface conduction electron-emitting device.

FIG. 3 is a schematic cross-sectional view of a method for manufacturing an electron-emitting device.

FIG. 4 is a voltage waveform of a forming process of the electron-emitting device of the present invention.

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

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

FIG. 7 is a schematic configuration diagram of an electron source having a simple matrix arrangement.

FIG. 8 is a schematic configuration diagram of a display panel using an electron source having a simple matrix arrangement.

FIG. 9 shows a fluorescent film.

FIG. 10 is a block diagram of a driving circuit in which an image forming apparatus performs display in accordance with an NTSC television signal.

FIG. 11 is a schematic configuration diagram of an electron source having a ladder arrangement.

FIG. 12 is a schematic configuration diagram of a display panel using an electron source in a ladder arrangement.

[Explanation of symbols]

1: substrate, 2: 3: device electrode, 4: conductive thin film, 5: electron emitting portion, 6: organometallic thin film, 31: ink jet device, 32: droplet, 33: liquid reservoir, 50: device current If Ammeter for measuring, 51: power supply for applying element voltage Vf,
52: ammeter for measuring emission current Ie, 53: high-voltage power supply, 54: anode electrode for capturing emission current Ie, 5
5: vacuum device, 56: exhaust pump, 71: electron source substrate,
72: X direction wiring, 73: Y direction wiring, 74: Surface conduction electron-emitting device, 75: Connection, 81: Rear plate, 8
2: support frame, 83: glass substrate, 84: fluorescent film, 85:
Metal back, 86: face plate, 87: high voltage terminal, 88: envelope, 91: black conductive material, 92: phosphor,
101: display panel 102: scanning circuit, 103: control circuit, 104: shift register, 105: line memory,
106: synchronization signal separation circuit, 107: modulation signal generator,
Vx and Va: DC voltage source, 110: electron source substrate, 1
11: electron-emitting device, 112 (Dx1 to Dx10): common wiring for wiring the electron-emitting device, 120: grid electrode, 121: hole for passing electrons, 12
2: Dox1 Dox2... Doxm external terminal, 123: G1, G connected to grid electrode 120
2.

Claims (8)

(57) [Claims] 1. A conductive thin film-forming material containing a metal composition to impart a state of <br/> droplets by an inkjet method between opposing substrate electrode, through more engineering for firing the electron emitting In the manufacturing method for forming an element, the substrate may include the droplet.
A method of manufacturing an electron-emitting device characterized by the granted position has a concave convex. 2. The method according to claim 1, wherein the electron-emitting device is a surface conduction electron-emitting device. 3. A method of manufacturing an electron-emitting device according to claim 1 or 2, wherein the ink jet method is characterized in that it is a bubble jet system. 4. The means for forming unevenness of the substrate,
4. The method according to claim 1, wherein the irradiation is ion irradiation.
A method for manufacturing an electron-emitting device according to any one of the preceding claims. 5. The means for forming unevenness of the substrate,
4. The method according to claim 1, wherein said etching is chemical etching.
A method for manufacturing the electron-emitting device according to any one of the above. 6. A method of manufacturing an electron source having a voltage application means to the electron emitting device and the element, produced by the process of any one of claims 1 to 5 the electron-emitting device A method of manufacturing an electron source. 7. A method for manufacturing a display panel, comprising: an electron source including an electron-emitting device and a means for applying a voltage to the device; and a luminous body that emits light by receiving electrons emitted from the device. The electron-emitting device according to any one of claims 1 to 5 ,
A method for manufacturing a display panel, comprising: manufacturing the display panel. 8. An electron source including an electron-emitting device and a means for applying a voltage to the device, a luminous body that receives and emits electrons emitted from the device, and applies the light to the device based on an external signal. 2. A method for manufacturing an image forming apparatus, comprising: a driving circuit for controlling a voltage;
7. A method for manufacturing an image forming apparatus, wherein the method is performed by the method according to any one of items 5 to 5 .