JP2002313220A - Electron emitting element, electron source, and method of manufacturing image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a preferable electron-emitting device in which a substrate 1 is coated with an antistatic film 6 without subjecting the surface of the substrate 1 to surface treatment for imparting hydrophobicity, by a droplet applying method. The stability of the shape and thickness of the conductive thin film 3 to be obtained can be enhanced. SOLUTION: Prior to formation of a conductive thin film 3, an antistatic film 6 is provided on a substrate 1 except for a region where the conductive thin film 3 is provided as an opening 6a. A liquid containing a conductive thin film component is applied as droplets into the opening 6a of the antistatic film 6 provided on the base 1,
By making the periphery of the opening 6a of the antistatic film 6 function as a weir, the spread of the droplet is regulated.

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 having a pair of device electrodes provided on an insulating substrate so as to face each other, and a conductive thin film provided in connection with the device electrodes. The present invention relates to an electron source in which a plurality of electron sources are arranged and a method for manufacturing an image forming apparatus using the electron source. For more information,
Manufacture of the electron-emitting device, the electron source, and the image forming apparatus, the method including a step of providing a conductive thin film by connecting to a pair of element electrodes provided to face each other on a substrate and a step of providing an antistatic film on the substrate. About the method.

[0002]

2. Description of the Related Art Conventionally, as an example of an electron-emitting device having a pair of device electrodes provided oppositely on an insulating substrate and a conductive thin film provided in connection with the device electrodes,
M. I. Elinson's "Radio Eng. E
electron Phys. , 10, 1290, (19
65)) is known. This surface conduction type electron-emitting device performs an electrical treatment called forming in advance on the conductive thin film, thereby locally destroying, deforming or altering the conductive thin film, thereby forming an electrically high-resistance containing crack. When a voltage is applied between the device electrodes and a current parallel to the surface of the conductive thin film flows, electrons are emitted from an electrically high-resistance portion (electron emission portion) including the crack. It utilizes the phenomenon that occurs.

The above-mentioned surface conduction electron-emitting devices have a simple structure, are easily miniaturized, and are easily arranged in large numbers over a large area. Therefore, both ends of many surface conduction electron-emitting devices are interconnected (also referred to as common interconnection). It has been proposed that a plurality of rows are connected to each other to form an electron source (for example, JP-A-64-031332 and JP-A-1-283737).
No. JP-A-2-257552). It has also been proposed to combine an electron source as described above with a phosphor that emits visible light by electrons emitted from the electron source to form an image forming apparatus (US Pat. No. 5,066,506).
883).

The formation of a conductive thin film in the above-described electron-emitting device is usually performed by a method mainly using a semiconductor process such as a vacuum deposition method, etching, and lift-off.

However, a method mainly using a semiconductor process requires a special and expensive manufacturing apparatus and a plurality of steps required for patterning. When forming an element, there is a problem that a production cost is required. Therefore, as a method of forming a conductive thin film without depending on a semiconductor process, it has been proposed to form a conductive thin film by applying a liquid containing a metal element constituting the conductive thin film as droplets.

That is, a metal element constituting a conductive thin film is interposed between element electrodes formed on a substrate by using, for example, an ink jet apparatus which discharges liquid droplets by the pressure of a piezoelectric element or the pressure of bubbles generated by heating. It has been proposed to apply a liquid containing as a liquid droplet and heat and sinter the liquid droplet to form a conductive thin film connected to the element electrode (Japanese Patent Application Laid-Open No. 9-6934,5).

By using such a droplet applying method, minute droplets of a liquid containing metal can be selectively applied only to desired positions, so that the conductive thin film material is wasted. There is no. Further, there is no need for a vacuum process requiring an expensive apparatus and patterning by photolithography including a number of steps, and there is an advantage that the production cost can be significantly reduced.

On the other hand, the electron-emitting device is driven in a vacuum, but if the surface of the insulating substrate is exposed near the electron-emitting portion, the surface is charged and the electron emission becomes unstable. In particular, a discharge occurs at a high potential, which may cause damage to the electron-emitting device. In order to prevent the instability of the electron emission characteristics and the deterioration of the electron emission element due to the discharge without lowering the electron emission efficiency, the generation of the leakage current is so small that it does not substantially matter, and the charging can be prevented. It is also known to coat a substrate surface with an antistatic film so as not to be exposed (JP-A-8-180801). Note that the electron emission efficiency refers to a current flowing between the device electrodes (device current If) and a current emitted into the vacuum (emission current I when a voltage is applied between a pair of device electrodes).
e), and the leak current refers to a current flowing between the device electrodes via the antistatic film.

[0009]

However, the formation of the conductive thin film by the application of the above-mentioned liquid droplets involves the irregular spread of the liquid droplets on the surface of the substrate, and the formation and the size of the formed conductive thin film are irregular. In order to prevent this, it is preferable to perform a surface treatment that makes the surface of the substrate hydrophobic. Specifically, HMDS (hexamethyldisilazane), PHAM
It is preferable to apply a silane coupling agent such as S, GMS, MAP, or PES to the surface of the base using, for example, a spinner or the like, and then perform baking at 100 ° C. to 300 ° C. in an oven for several minutes to several hours.

By performing the above-mentioned surface treatment, it is possible to prevent the droplets applied to the substrate surface from spreading irregularly and to improve the shape stability of the droplets. And the reproducibility and uniformity of the thickness are improved. As a result, even when a large number of electron-emitting devices are formed over a large area, the electron-emitting characteristics of each electron-emitting device can be made uniform.

However, the above-mentioned surface treatment for imparting hydrophobicity requires, for example, application of a silane coupling agent and baking thereof. One of the advantages of employing the droplet applying method for forming the conductive thin film is one of the advantages. However, there is a problem that the simplification of the manufacturing process of the electron-emitting device is diminished.

On the other hand, from the viewpoint of stabilizing the electron emission characteristics of the electron-emitting device and preventing deterioration of the electron-emitting device due to discharge, it is preferable to coat the substrate with the antistatic film. Coating is not specifically proposed as a technique associated with the droplet application method described above.

According to the present invention, in producing a preferable electron-emitting device in which a substrate is coated with the above antistatic film, a conductive film obtained by a droplet applying method without performing a surface treatment for imparting hydrophobicity to the surface of the substrate. It is an object of the present invention to improve the stability of the shape and thickness of the sheet.

[0014]

In order to achieve the above object, a first aspect of the present invention is to provide an element electrode forming step of providing a pair of opposing element electrodes on an insulating substrate, and a method of forming the pair of element electrodes. A method for manufacturing an electron-emitting device, comprising: a conductive thin-film forming step of providing a conductive thin film connected to each of the conductive thin films; and an electron-emitting portion forming step of forming an electron-emitting portion on a part of the conductive thin film. Prior to the conductive thin film forming step, there is provided an antistatic film forming step of providing an antistatic film on the base except for a region where the conductive thin film is provided in the conductive thin film forming step as an opening; An electron-emitting device, wherein the step of forming a conductive thin film includes a step of applying a liquid containing a conductive thin-film component as liquid droplets in an opening of the antistatic film provided on the substrate in the step of forming the antistatic film. Manufacturing of It is intended to provide the law.

According to the present invention, the peripheral edge of the opening of the antistatic film prevents the droplet applied in the opening from spreading irregularly and regulates the shape of the droplet applied in the opening. It functions as a weir. Therefore, according to the present invention, the shape of the droplet can be made uniform without performing a treatment for making the substrate surface hydrophobic.

In the present invention, the step of forming the antistatic film and the step of forming the conductive thin film may be performed after the step of forming the device electrode.
In the antistatic film forming step, the opposite end portions of the pair of element electrodes provided in the element electrode forming step are positioned in the opening, and after forming the antistatic film from above the pair of element electrodes, the conductive Performing a thin film forming process; the antistatic film forming process and the conductive thin film forming process are performed before the element electrode forming process, and the conductive film is formed in the opening of the antistatic film provided in the antistatic film forming process. After the conductive thin film is provided, in the device electrode forming step, the device electrode is provided on the conductive thin film provided in the opening of the antistatic film; droplets of the conductive thin film component-containing liquid in the conductive film forming process In a preferred embodiment of the present invention, the application of the pressure is performed by an ink jet apparatus that ejects liquid droplets by a pressure of a piezoelectric element or a pressure of a bubble generated by heating.

Further, according to the present invention, there is provided a method of manufacturing an electron source, wherein a plurality of electron-emitting devices are formed on a common substrate by any one of the above-described methods of manufacturing an electron-emitting device.
Further, the present invention also provides a method of manufacturing an image forming apparatus, wherein an electron source manufactured by the method of manufacturing an electron source is combined with an image forming member that forms an image by irradiating an electron beam from the electron source. is there.

[0018]

FIG. 1 is a schematic diagram showing an example of an electron-emitting device manufactured according to the present invention.
Is a plan view, and (b) is a sectional view.

In FIG. 1, 1 is a substrate, 2 is an electron emitting device,
Reference numeral 3 denotes a conductive thin film including the electron emitting portion 2, 4 and 5 denote device electrodes, 6 denotes an antistatic film, and 6a denotes an opening of the antistatic film 6.

The substrate 1 is electrically insulative, for example, quartz glass, glass with a reduced content of impurities such as Na, blue plate glass, or a laminate of a blue plate glass and a SiO ₂ film laminated by a sputtering method or the like. A body, ceramics such as alumina, and a plate-like material such as a so-called Si substrate can be used.

A pair of opposing element electrodes 4 and 5 are provided on the base 1. As the material of the device electrodes 4 and 5, a general conductor material can be used. For example, Ni, Cr, Au, Mo, W, Pt, Ti, A
metals or alloys such as l, Cu, Pd, Pd, Ag, A
a printed conductor composed of a metal such as u, RuO ₂ , Pd—Ag or a metal oxide and glass; In ₂ O ₃ —SnO
₂ or a semiconductor material such as polysilicon.

The distance L between the device electrodes 4 and 5, the device electrode 4,
The width W of the device electrode 5 and the film thickness d of the device electrodes 4 and 5 are designed in consideration of the applied form and the like. A preferable distance L between the device electrodes 4 and 5 is several hundred nm to several hundred μm. And more preferably in the range of several μm to several tens μm.
The width W of the preferred device electrodes 4 and 5 is in the range of several μm to several hundred μm in consideration of the resistance value of the electrodes and the electron emission characteristics. The range is from nm to several μm.

The surface of the substrate 1 on which the device electrodes 4 and 5 are provided has an antistatic film 6 provided over the device electrodes 4 and 5 except for a region extending between the device electrodes 4 and 5 as an opening 6a. It is covered with. That is, on the surface of the base 1, the antistatic film 6 in which the formation region of the conductive thin film 3 including the electron-emitting portion 2 is the opening 6a is provided.

As described above, it is preferable that the antistatic film 6 is so small that the generation of a leak current does not substantially cause a problem. However, in order to prevent discharge, the sheet resistance value is 10 ¹² Ω /. □ or less, and a sheet resistance of 10 ¹⁰ Ω /
□ It is preferable that it is the following. In addition, the antistatic film 6
It is preferable that a large-area uniform film is formed of a material that can be easily obtained, for example, a carbon material, a metal oxide such as tin oxide or chromium oxide, or a material in which a conductive material is dispersed in silicon oxide or the like. And the like.

The illustrated opening 6a has a circular shape with a diameter W ', but the opening 6a in the present invention is not limited to this, and may have other shapes such as a rectangle and an ellipse. Although good, a circle is preferable from the shape of the droplet in the droplet method described later. Further, the size can be appropriately determined according to, for example, the size of the element electrodes 4 and 5.

In the opening 6a of the antistatic film 6, a conductive thin film 3 having an electron emitting portion 2 is provided from an end of the element electrodes 4 and 5 located in the opening 6a on opposite sides. Thus, the conductive thin film 3 and the device electrodes 4 and 5 are electrically connected. The conductive thin film 3 having the electron-emitting portion 2 has a planar contour defined by the periphery of the opening 6 a of the antistatic film 6, and the planar shape is the planar shape of the opening 6 a of the antistatic film 6. It has a shape along.

Here, the conductive thin film 3 including the electron emitting portion 2
Is preferably a fine particle film composed of fine particles in order to obtain good electron emission characteristics. A fine particle film is a film in which a plurality of fine particles are aggregated.
The film refers not only to a state in which fine particles are individually dispersed and arranged, but also to a film in which fine particles are adjacent to each other or overlap each other (including an island shape). The film thickness is appropriately set in consideration of the step coverage to the device electrodes 4 and 5, the resistance between the device electrodes 4 and 5, a forming condition described later, and the like.
It is preferably in the range of several times 0.1 nm to several hundred nm, more preferably in the range of 1 nm to 50 nm.

Further, the conductive thin film 3 including the electron emitting portion 2
Preferably has a sheet resistance of 10 ⁷ Ω / □ or less. The sheet resistance value of the conductive thin film 3 including the electron emitting portion 2 is a sheet resistance value of the conductive thin film 3 measured in a region not including the electron emitting portion 2 after the electron emitting portion 2 is formed.
The sheet resistance is preferably the above-described value in order to form a favorable electron-emitting portion 2 in a later-described forming step of the electron-emitting portion 2, that is, a forming step. The more preferable sheet resistance value of the conductive thin film 3 including the electron-emitting portion 2 is in the range of 10 ³ Ω / □ to 10 ⁷ Ω / □.

The sheet resistance value is Rs that satisfies R = Rs · (l / w), where R is the resistance of a thin film having a width w and a length l.

However, after the formation of the electron-emitting portion 2, it is preferable that the voltage applied through the device electrodes 4 and 5 is sufficiently applied to the electron-emitting portion 2, and the conductive thin film 3 including the electron-emitting portion 2 is formed. Is preferably lower.
Therefore, as will be described in detail later, the conductive thin film 3 before forming the electron emitting portion 2 is formed as a metal oxide semiconductor thin film having a sheet resistance value in the range of 10 ³ Ω / □ to 10 ⁷ Ω / □. And after forming the electron-emitting portion 2 (after forming)
It is preferable that the conductive thin film 3 having the electron emitting portion 2 is reduced to a metal thin film having a lower resistance. Therefore,
The lower limit of the resistance value of the conductive thin film 3 including the electron-emitting portion 2 in the final state is not particularly limited.

The material constituting the conductive thin film 3 is Pd, P
t, Ru, Ag, Au, Ti, In, Cu, Cr, F
e, metal such as Zn, Sn, Ta, W, Pb, PdO,
SnO _Two, In_TwoO_Three, PbO, Sb_TwoO_ThreeOxides, such as
HfB_Two, ZrB_Two, LaB₆, CeB₆, YB_Four, GdB_Four
Boride such as TiC, ZrC, HfC, TaC, Si
Carbides such as C and WC, TiN, ZrN, HfN, etc.
In semiconductors such as nitride, Si, Ge, and carbon
Selected as appropriate. Further, a material constituting the conductive thin film 3
Is a combination of two or more of these
It may be.

The electron emitting portion 2 is a portion where electrons are emitted when a voltage is applied between the device electrodes 4 and 5.
This is an electrically high-resistance portion including a crack formed in a part of. In some cases, conductive fine particles having a particle size in the range of several times 0.1 nm to several tens of nm exist inside the electron emitting portion 2. The conductive fine particles contain some or all of the elements of the material constituting the conductive thin film 3. Further, it is preferable that the electron emitting portion 2 and the conductive thin film 3 in the vicinity thereof contain carbon and a carbon compound.

FIGS. 2A and 2B are schematic structural views showing another example of the electron-emitting device manufactured according to the present invention, wherein FIG. 2A is a plan view and FIG. 2B is a sectional view. In FIG. 2, the same reference numerals as those in FIG. 1 indicate the same parts or members.

In the electron-emitting device shown in FIG. 2, an antistatic film 6 is provided below the device electrodes 4 and 5. That is,
The electron-emitting device shown in FIG. 1 has an antistatic film 6 provided after the device electrodes 4 and 5 are provided on the base 1, whereas the electron-emitting device shown in FIG. 2 has the antistatic film 6 provided on the base. After that, device electrodes 4 and 5 are provided.

The antistatic film 6 in this embodiment has an opening 6a similarly to the antistatic film of FIG. In other words, the surface of the base 1 is covered with the antistatic film 6 except for the region where the conductive thin film 3 having the electron emitting portion 2 is formed as the opening 6a.

In the opening 6a of the antistatic film 6, a conductive thin film 3 having an electron emitting portion 2 is provided. The conductive thin film 3 having the electron-emitting portion 2 has a planar contour defined by the periphery of the opening 6 a of the antistatic film 6, and has a planar shape of the opening 6 a of the antistatic film 6.
The shape is in accordance with the planar shape of.

The device electrodes 4 and 4 of the electron-emitting device in this embodiment
5 is provided on the antistatic film 6 and the conductive thin film 3 so that at least a part thereof overlaps the conductive thin film 3, whereby the conductive thin film 3 and the device electrode 4 are provided.
5 is electrically connected.

Next, a method for manufacturing the electron-emitting device shown in FIG. 1 will be described step by step with reference to FIGS. In FIG. 3, the same parts as those shown in FIG. 1 are denoted by the same reference numerals as those in FIG.

(1) After subjecting the substrate 1 to a pretreatment for sufficiently washing it with a detergent, pure water, an organic solvent or the like, the constituent materials of the device electrodes 4 and 5 are removed by a vacuum deposition method, a sputtering method or the like. Then, the device electrodes 4 and 5 are formed by using, for example, a photolithography technique (device electrode forming process; FIG. 3).
(A)).

(2) Next, an antistatic film 6 is formed on the substrate 1 (antistatic film forming step; FIG. 3B). The antistatic film forming step in this example is performed on the base 12 provided with the device electrodes 4 and 5.

Examples of the method for forming the antistatic film 6 include a sputtering method, a vacuum evaporation method, a coating method, a polymerization method using an electron beam with a carbon-based gas, a plasma method, and a CVD method. Antistatic film 6
Can be easily obtained. A detailed film forming method will be described in an example described later.

The antistatic film 6 is provided except that a region where the conductive thin film 3 including the electron emitting portion 2 is to be provided later is formed as an opening 6a. The antistatic film 6 has a pair of device electrodes 4 previously formed on the base 1. , 5 are provided from above the pair of element electrodes 4, 5 with the opposing ends of the element electrodes 4, 5 positioned in the opening 6 a.

The formation of the antistatic film 6 excluding the formation region of the conductive thin film 3 including the electron-emitting portion 2 as the opening 6a is performed by patterning by lift-off, etching, or the like using, for example, photolithography technology. Is possible more easily. As described above, the opening 6a is preferably circular in consideration of the shape of the droplet applied when the conductive thin film 3 is formed. The opening 6a is
If this is a circle, its diameter W 'is usually several μm
To several hundred μm.

(3) Next, the liquid containing the conductive thin film component is discharged as droplets from the droplet applying device 7, and the opening 6a
After the droplets are applied to the inside of the device electrodes 4 and 5 exposed in the opening 6a, the film is dried and thinned, or if necessary, further heated (baked) after drying. A conductive thin film 3 connected to the device electrodes 4 and 5 is formed so as to cover the opposite side end (conductive thin film forming step; FIG. 3C,
(D)). The liquid droplets provided in the opening 6a substantially follow the opening 6a because the peripheral edge of the opening 6a of the antistatic film 6 functions as a weir and is prevented from spreading irregularly beyond this. The dimensional stability and uniformity of the conductive thin film 3 are improved by controlling the flat shape.

The application of the conductive thin film component-containing liquid as droplets is preferably performed as minute droplets in the range of about 10 ng to several tens ng, for example, preferably performed by an ink jet apparatus. As the ink jet device, there are a piezoelectric element system in which droplets are ejected by pressure from a piezoelectric element and a heating system in which droplets are ejected by pressure caused by bubbles generated by heating, and any of them can be used. As a specific example of the heating type inkjet apparatus, there is Bubble Jet (registered trademark) manufactured by Canon Inc.

The conductive thin film component-containing liquid is a solution or dispersion containing at least the above-mentioned metal element which is a constituent material of the conductive thin film 3, and is a metal or a metal compound listed as an example of the constituent material of the conductive thin film 3. In addition to the above solution or dispersion, a metal compound which becomes a constituent material of the conductive thin film 3 through an oxidation treatment, a reduction treatment, a nitridation treatment, or the like may be used. The conductive thin film component-containing liquid can be obtained as a solution in which the metal or the metal compound is dissolved in water or a solvent, or an organic metal solution, or a solution in which fine particles of the metal or the metal compound are dispersed in a binder solution. .

(4) The conductive thin film 3 formed as described above is subjected to forming for forming the electron emitting portions 2 (electron emitting portion forming step; FIG. 3E). As an example of this forming, energization forming by energization processing will be described.

When current is applied between the device electrodes 4 and 5 using a power supply (not shown), an electron emitting portion 2 having a changed structure is formed in a part of the conductive thin film 3. That is, due to this energization, a portion of the conductive thin film 3 whose structure such as destruction, deformation or alteration is locally formed is formed, and this portion constitutes the electron emission portion 2.

FIG. 4 shows an example of the voltage waveform of the energization forming.

The voltage waveform is preferably a pulse waveform. For this purpose, a method shown in FIG. 4A for continuously applying a pulse having a pulse peak value as a constant voltage, or a method of increasing the pulse peak value while increasing the pulse peak value is used. There is a method shown in FIG. 4B for applying a pulse.

T1 and T2 in FIG. 4A are the pulse width and pulse interval of the voltage waveform, respectively. Normal T
1 is in the range of 1 μs to 10 ms, and T2 is 10 μs
It is set in the range of 10 to 10 ms. The illustrated pulse waveform is a triangular wave, and the peak value of this triangular wave (peak voltage at the time of energization forming) is appropriately selected according to the form of the electron-emitting device. Under such conditions, for example, several seconds to several tens of Apply voltage for one minute. Note that the pulse waveform is not limited to a triangular wave, and other waveforms such as a rectangular wave can be adopted.

The values of T1 and T2 in FIG. 4B can be the same as those shown in FIG. The peak value of the triangular wave (peak voltage at the time of energization forming) in FIG. 4B can be increased, for example, in steps of about 0.1 V.

The end time of the energization forming process can be detected by applying a voltage that does not locally destroy or deform the conductive thin film 3 during the pulse interval T2 and measuring the current. For example, a device current flowing by applying a voltage of about 0.1 V is measured, and a resistance value is obtained.
When the resistance shows MΩ or more, the energization forming can be terminated.

(5) After the above-mentioned electron emitting portion forming step is completed, it is preferable to perform a step called an activation step.

The activation process is a process for significantly changing the device current If and the emission current Ie. This process is performed, for example, in an atmosphere containing an organic substance gas in the same manner as in energization forming. This can be performed by repeating the application of the pulse.

The atmosphere containing the organic substance gas is as follows:
For example, when the inside of a vacuum container is evacuated using an oil diffusion pump or a rotary pump, it can be formed by using a gas of an organic substance remaining in the atmosphere, or in 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.

At this time, the preferable gas pressure of the organic substance is:
Since it differs depending on the use of the obtained electron-emitting device, the shape of the vacuum vessel, the type of the organic substance, and the like, it is set as appropriate according to the case.

Suitable organic substances include aliphatic hydrocarbons such as alkanes, alkenes, and alkynes, aromatic hydrocarbons, alcohols, aldehydes, ketones, amines, phenols, carboxylic acids, and organic acids such as sulfonic acids. And the like. Specifically, saturated hydrocarbons represented by C _n H _{2n + 2} such as methane, ethane and propane; unsaturated hydrocarbons represented by a composition formula such as C _n H _2n such as ethylene and propylene; benzene and toluene , Methanol, ethanol, formaldehyde, acetaldehyde, acetone, methyl ethyl ketone, methylamine, ethylamine, phenol, formic acid, acetic acid, propionic acid and the like, or a mixture thereof.

In the activation step, carbon or a carbon compound is deposited from the organic substance existing in the atmosphere in and around the electron-emitting portion 2, and the device current If and the emission current Ie are significantly changed. It is preferable to appropriately determine the end time of the activation step while measuring the element current If and the emission current Ie. Further, a pulse width, a pulse interval, a pulse crest value, and the like for the processing in the activation step are appropriately set.

The carbon or carbon compound includes, for example, graphite (so-called HOPG, PG, GC), HOPG has a crystal structure of almost perfect graphite, and PG has a crystal grain of about 20 nm and the crystal structure is slightly disordered. And GC is one in which the crystal grains are about 2 nm and the disorder of the crystal structure is further increased) or amorphous carbon (indicating amorphous carbon, a mixture of amorphous carbon and the fine crystals of graphite), The deposited film thickness is preferably in the range of 50 nm or less, more preferably in the range of 30 nm or less.

(6) It is preferable that the electron-emitting device obtained through such an activation step is further subjected to a treatment called a stabilization step.

This step is a step of exhausting the organic substance in the vacuum vessel.

Here, it is preferable to use a vacuum-evacuation device that does not use oil so as to prevent the oil generated from the device from affecting the characteristics of the electron-emitting device. Specifically, it is preferable to use a vacuum exhaust device such as a sorption pump or an ion pump. Further, in the activation step, when an oil diffusion pump or a rotary pump is used as a vacuum pump and an organic substance gas derived from an oil component generated from the oil diffusion pump or the rotary pump is used, the partial pressure of this component in the stabilization step is minimized. Keep it low.

The partial pressure of the organic component in the vacuum vessel is a partial pressure at which the carbon or carbon compound is hardly newly deposited.
It is preferably at most 1.3 × 10 ⁻⁶ Pa, particularly preferably at most 1.3 × 10 ⁻⁸ Pa.

When the inside of the vacuum vessel is evacuated, it is preferable to heat the entire vacuum vessel so as to easily evacuate the organic substance molecules adsorbed on the inner wall of the vacuum vessel and the electron-emitting device. The heating conditions at this time are preferably from 80 to 300 ° C., particularly preferably 150 ° C. or higher. Also,
It is desirable to perform the treatment for as long a time as possible, but it is not particularly limited to this condition, and it is preferable to appropriately determine the condition 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 is preferably as low as possible, preferably 1 × 10 ⁻⁵ Pa or less, and particularly preferably 1.3 × 10 ⁻⁶ Pa or less.

It is preferable that the atmosphere at the time of driving after the stabilization step is performed is the same as that at the end of the stabilization step. However, the present invention is not limited to this. Even if the degree of vacuum itself is slightly reduced, sufficiently stable characteristics can be maintained.

By adopting such a vacuum atmosphere, the deposition of new carbon or carbon compound can be suppressed.
Further, H ₂ O, O _2, etc. adsorbed on the vacuum vessel or the substrate 1 can be removed, and as a result, the device current If and the emission current Ie
Becomes stable.

In the manufacture of the electron-emitting device shown in FIG. 2, first, the electron-emitting portion 2 is placed on the pretreated base 1.
The antistatic film 6 is provided except for a region where the conductive thin film 3 including the conductive film 3 is provided as the opening 6a (conductive thin film forming step). Next, the conductive thin film 3 is provided through the application of the conductive thin film component-containing liquid as droplets into the opening 6a (conductive thin film forming step). After forming the device electrodes 4 and 5 on the conductive thin film 6 provided in the opening 6a (device electrode forming process), the electron emitting portion forming process, the activation process, and the stabilizing process are sequentially performed. By performing the application, the electron-emitting device described with reference to FIG. 2 can be obtained.

The basic characteristics of the electron-emitting device obtained through the above-described steps will be described with reference to FIGS. 5 and 6, taking the electron-emitting device described with reference to FIG. 1 as an example. In addition,
5, the same parts as those shown in FIG. 1 are denoted by the same reference numerals as those shown in FIG.

The characteristics of the electron-emitting device can be measured by, for example, a vacuum processing apparatus as shown in FIG. 5, which also has a function as a measurement and evaluation apparatus.

In FIG. 5, reference numeral 55 denotes a vacuum vessel,
Reference numeral 6 denotes an exhaust pump.

An electron-emitting device is provided in the vacuum vessel 55. As described with reference to FIG.
On a substrate 1, there are provided device electrodes 4 and 5, an antistatic film 6a having an opening 6a, and a conductive thin film 3 including an electron emitting portion 2.

Reference numeral 51 denotes a power supply for applying a device voltage Vf to the electron-emitting device; 50, an ammeter for measuring a device current If flowing through the conductive thin film 3 between the device electrodes 4 and 5;
Is an anode electrode for capturing the emission current Ie emitted from the electron emission portion 2 of the device. 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 2 of the device.

The vacuum vessel 55 is provided with equipment required for measurement in a vacuum atmosphere, such as a vacuum gauge (not shown), so that measurement and evaluation in a desired vacuum atmosphere can be performed. The exhaust pump 56 is composed of a normal high vacuum device system including a turbo pump and a rotary pump, and an ultrahigh vacuum device system including an ion pump and the like. It can be heated by a heater. Therefore, the vacuum processing apparatus shown in FIG. 5 can perform the steps after the above-described step of forming the electron-emitting portion by the energization forming.

The measurement of the characteristics of the electron-emitting device by the vacuum processing apparatus is performed, for example, by setting the voltage of the anode electrode 54 to 1 kV or more.
The range can be set to 10 kV, and the distance H between the anode electrode 54 and the electron-emitting device can be set to a range of 2 mm to 8 mm.

FIG. 6 shows the emission current Ie, the device current If, and the device voltage V measured using the vacuum processing apparatus shown in FIG.
It is the figure which showed the relationship of f typically. In FIG.
Since the emission current Ie is significantly smaller than the element current If, it is shown in arbitrary units. The vertical and horizontal axes are linear scales.

As is clear from FIG. 6, the electron-emitting device configured as described above has the following three characteristic properties with respect to the emission current Ie.

(I) In the present electron-emitting device, when an element voltage higher than a certain voltage (referred to as a threshold voltage, Vth in FIG. 6) is applied, the emission current Ie sharply increases. Below Vth, 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 understood from the above description, the electron-emitting device manufactured according to the present invention can easily control the electron-emitting characteristics according to the input signal.

That is, the emission electrons from the electron-emitting device can be controlled by the peak value and the width of the pulse-like voltage applied between the opposing device electrodes 4 and 5 above the threshold voltage, but below the threshold voltage. Is hardly released. According to this characteristic, even when a large number of electron-emitting devices are arranged, if a pulse-like voltage is appropriately applied to each of the electron-emitting devices, the electron-emitting device is selected according to an input signal to reduce the amount of electron emission. It can be controlled and can be applied to various fields such as an electron source and an image forming apparatus in which a plurality of electron-emitting devices are arranged on a common base.

Next, an application example of the above-described electron-emitting device will be described below.

As the arrangement of the electron-emitting devices, various arrangements can be employed.
A plurality of electron-emitting devices arranged in a matrix in the direction and the Y-direction, and one of the plurality of electron-emitting devices arranged in the same row is commonly connected to one of the device electrodes 5 or 4 and the other device electrode 5 or 4, respectively. Direction perpendicular to this wiring (referred to as column direction)
There is a ladder arrangement in which electrons from the electron-emitting device are controlled and driven by a control electrode (also referred to as a grid) disposed above the electron-emitting device.

Separately, a plurality of electron-emitting devices are arranged in a matrix in the X and Y directions, and one of the device electrodes 4 and 5 of the plurality of electron-emitting devices arranged in the same row is And the other of the device electrodes 4 and 5 of the plurality of electron-emitting devices arranged in the same column are commonly connected to the wiring in the Y direction. This is a so-called simple matrix arrangement. This simple matrix arrangement will be described in detail below.

In FIG. 7, 1 is a substrate, and 72 is X
Reference numeral 73 denotes a Y-direction wiring, 74 denotes an electron-emitting device, and 75 denotes a connection.

The X-direction wiring 72 includes Dx1, Dx2,.
.., M wirings of Dxm, and can be made of a conductive metal or the like provided by using a printing method, a vacuum evaporation method, a sputtering method, or the like. The Y direction wiring 73 is Dy1,
.., Dyn are formed in the same manner as the X-direction wiring 72. In each case, the material, thickness and width of the wiring are appropriately designed. Note that m and n are both positive integers.

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. The interlayer insulating layer (not shown) can be composed of a SiO ₂ or PbO film formed by using a printing method, a vacuum evaporation method, a sputtering method, or the like. The interlayer insulating layer is formed, for example, of the X-direction wiring 7.
The film 2 is formed in a desired shape on the entire surface or a part of the substrate 1 on which the substrate 2 is formed. In particular, the film thickness, material, and manufacturing method are appropriately set so as to withstand the potential difference at the intersection of the X-directional wiring 72 and the Y-directional wiring 73. Is done.

The X-directional wiring 72 and the Y-directional wiring 73 are drawn out as external terminals.

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

The material forming the X-direction wiring 72 and the Y-direction wiring 73, the material forming the connection 75, and the material forming the pair of element electrodes may be identical or partially identical to the constituent elements. Each may be different. These materials are appropriately selected, for example, from the above-mentioned materials for the device electrodes. The material constituting the element electrode and the connection 75, the X-direction wiring 72 and the Y-direction wiring 7
In the case where the materials of No. 3 are the same, the connection 75 connected to the device electrode, and a part of the X-direction wiring 72 and the Y-direction wiring 73 can also be referred to as a device electrode.

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

In the above configuration, individual electron-emitting devices can be selected and driven independently using a simple matrix wiring.

A simple matrix arrangement of electron sources obtained by the present invention will be described with reference to FIGS.

FIG. 8 is a schematic view showing an example of a simple matrix electron source obtained by the present invention, and FIG. 9 is a schematic view showing a manufacturing process.

In FIG. 8, 1 is a substrate, 2 is an electron emitting portion, 3 is a conductive thin film including the electron emitting portion 2, 4 and 5 are device electrodes, 6 is an antistatic film having an opening 6a, and 72 is X Reference numeral 73 denotes a Y-directional wiring, and reference numeral 81 denotes an interlayer insulating layer.
The configuration of each electron-emitting device is as described in FIG.
The connection state of each electron-emitting device is the same as that shown in FIG.

Here, in the electron source as shown in FIG. 8, it is preferable to consider not only the vicinity of the electron-emitting device but also the other insulating portions to prevent charging.

That is, the device electrodes 4 of each electron-emitting device
X-direction wiring 73 and Y-direction wiring 7 connected to
2 are formed in a matrix and the X-direction wiring 73 and the Y-direction wiring 72 are electrically separated by an interlayer insulating layer 81, the antistatic film 6 is also formed on the surface of the interlayer insulating layer 81. Is preferred. However, the antistatic film 6 formed on the surface of the interlayer insulating layer 81 does not need to be the same as the antistatic film formed at the time of manufacturing the above-described electron-emitting device.

The manufacturing process of the electron source shown in FIG. 8 will be described with reference to FIG.

In FIG. 9, as in FIG. 8, 1 is a substrate, 2 is an electron emitting portion, 3 is a conductive thin film including the electron emitting portion 2, 4 and 5 are device electrodes, and 6 has an opening 6a. 8 is an antistatic film, 72 is an X direction wiring, 73 is a Y direction wiring,
1 is an interlayer insulating layer.

(1) After a pretreatment for sufficiently cleaning the substrate 1 using a detergent, pure water, an organic solvent, or the like, a device electrode material is deposited by a vacuum deposition method, a sputtering method, or the like. Then, device electrodes 4 and 5 are formed (device electrode forming step; FIG. 9A).

(2) A Y-directional wiring 73 is formed on the substrate 1 provided with the device electrodes 4 and 5 so as to be in contact with the device electrodes 5 by a printing method, a vacuum deposition method, a sputtering method or the like. Forming with metal or the like (Y-direction wiring forming step; FIG. 9)
(B)).

(3) An interlayer insulating layer 81 is provided at least at the intersection between the Y-directional wiring 73 and the X-directional wiring 72 so as to electrically separate them from each other (interlayer insulating layer forming step; FIG. 9C )). The interlayer insulating layer 81 can be obtained by forming an insulator layer of SiO ₂ , PbO, or the like into a desired shape by using a printing method, a vacuum evaporation method, a sputtering method, or the like. In particular, the film thickness, material, and manufacturing method are appropriately set so as to withstand the potential difference at the intersection.

(4) The X-direction wiring 72 is connected to the interlayer insulating layer 81
It is formed of a conductive metal or the like formed by using a printing method, a vacuum deposition method, a sputtering method, or the like so as to intersect with the Y-direction wiring 73 and to be in contact with the device electrode 4 (X-direction wiring forming step; FIG. 9 (d)).

(5) Antistatic film 6 having opening 6a
Is formed in portions other than the portion where the conductive thin film 3 including the electron-emitting portion 2 is formed by patterning by lift-off, etching, or the like using, for example, photolithography technology (antistatic film forming step; FIG. 9).
(E)).

The formation of the antistatic film 6 is described in FIG.
As shown in FIG. 8E, if it is formed on all parts except the part where the conductive thin film 3 including the electron emission part 2 is formed, the electron source shown in FIG. 8A can be manufactured. However, it is not necessary to form the conductive thin film 3 on the X-directional wiring 72 and the Y-directional wiring 73. Since the object of the invention can be achieved, if the antistatic film 6 is formed in a region except on the X-directional wiring 72 and the Y-directional wiring 73, the electron source shown in FIG. 8B can be manufactured. it can. In any case, the interlayer insulating layer 81
By simultaneously forming the antistatic film 6 on the surface of the substrate, the interlayer insulating layer 81 can be prevented from being charged in the same film forming step, which is more effective.

Here, the material and the forming method of the antistatic film 6 are the same as those described in the method of manufacturing the electron-emitting device.

(6) Next, the above-described liquid containing the conductive thin film component is applied as droplets to each opening 6a of the antistatic film 6, and the conductive thin film 3 is dried or dried and heat-treated (fired). It is formed (FIG. 9F).

(7) Thereafter, an electron emitting portion forming step, an activating step, and a stabilizing step are performed. These steps are as described above.

The above manufacturing method is for the case where each of the electron-emitting devices has the structure described with reference to FIG. 1. However, when each of the electron-emitting devices has the structure described for FIG. The forming step, the element electrode forming step, the Y direction wiring forming step, the interlayer insulating layer forming step, the X direction wiring forming step, the conductive film forming step, the electron emitting portion forming step, the activation step, and the stabilizing step may be performed in this order. .

An image forming apparatus configured using such an electron source having a simple matrix arrangement will be described with reference to FIGS.

FIG. 10 is a schematic view showing an example of a display panel of the image forming apparatus, and FIG. 11 is a schematic view of a fluorescent film used in the image forming apparatus of FIG.

In FIG. 10, 1 is a base on which a plurality of electron-emitting devices are arranged, 101 is a rear plate on which the base 1 is fixed,
Reference numeral 106 denotes a face plate in which a fluorescent film 104 and a metal back 105 are formed on the inner surface of another substrate 103.

Reference numeral 102 denotes a support frame.
, The rear plate 101 and the face plate 106 are joined by using low melting point frit glass or the like. Reference numerals 72 and 73 denote an X-direction wiring and a Y-direction wiring connected to a pair of device electrodes of the electron-emitting device.

The envelope 108 includes the face plate 106, the support frame 102, and the rear plate 101 as described above. Since the rear plate 101 is provided mainly for the purpose of reinforcing the strength of the base 1, when the base 1 itself has sufficient strength, the rear plate 101 separate from the base 1 is provided.
Can be unnecessary. That is, the support frame 102 is directly sealed to the base 1, and the face plate 106, the support frame 1
02 and the base 1 can constitute the envelope 108.

On the other hand, by providing a support (not shown) called a spacer between the face plate 106 and the rear plate 101, the envelope 108 having sufficient strength against atmospheric pressure can be formed. Can also.

FIG. 11 is a schematic diagram showing a fluorescent film.

In the case of monochrome, the fluorescent film 104 can be composed of only the phosphor (112 in FIG. 11). In the case of the color fluorescent film 104, the fluorescent film 112 may be composed of a black conductive material 111 called a black stripe (FIG. 11A) or a black matrix (FIG. 11B) depending on the arrangement of the fluorescent materials. it can.

The purpose of providing the black stripes and the black matrix is to make the color separation between the phosphors 112 of the necessary three primary color phosphors black in color display so that color mixing and the like become inconspicuous. The object is to suppress a decrease in contrast due to reflection of external light on the film 104. As a material of the black conductive material 111 constituting the black stripe or the black matrix, in addition to a commonly used material containing graphite as a main component, a material having conductivity and having little light transmission and reflection can be used. .

The method of applying the fluorescent substance to the glass substrate 103 can employ a precipitation method, a printing method, or the like irrespective of monochrome or color.

A metal back 105 is usually provided on the inner surface side of the fluorescent film 104. The purpose of providing the metal back is to improve the brightness by mirror-reflecting the light toward the inner surface side of the light emitted from the phosphor 112 toward the face plate 106, and to act as an electrode for applying an electron beam acceleration voltage. And protecting the phosphor 112 from damage caused by collision of negative ions generated in the envelope 108.

The metal back is formed by smoothing the inner surface of the fluorescent film 104 (usually,
This is called "filming." ), And thereafter, Al or the like is deposited using vacuum evaporation or the like.

In the face plate 106, a transparent electrode (not shown) may be provided on the outer surface side of the fluorescent film 104 in order to further increase the conductivity of the fluorescent film 104.

When performing the above-mentioned sealing, in the case of color, it is necessary to make each color phosphor 112 correspond to the electron-emitting device, and it is preferable to perform sufficient alignment.

A method of manufacturing the display panel shown in FIG. 10, in particular, an example of steps after the step of forming an electron-emitting portion will be described below.

FIG. 12 is a schematic diagram showing an outline of an apparatus used in this step.

The display panel 121 is connected to a vacuum chamber 123 via an exhaust pipe 122, and further connected to an exhaust device 125 via a gate valve.

The vacuum chamber 123 is provided with a pressure gauge 126, a quadrupole mass analyzer 127, and the like for measuring the internal pressure and the partial pressure of each component in the atmosphere. Since it is difficult to directly measure the pressure inside the envelope 108 of the display panel 121, the pressure and the like of the vacuum chamber 123 are measured to control the processing conditions.

A gas introduction line 128 is connected to the vacuum chamber 123 to introduce necessary gas into the vacuum chamber and control the atmosphere. An introduction substance source 130 is connected to the other end of the gas introduction line 128, and the introduction substance is stored in an ampoule, a cylinder or the like.

In the middle of the gas introduction line 128, the introduction control means 12 for controlling the rate of the introduced substance is introduced.
9 are provided. Specifically, as the introduction amount control means 129, a valve capable of controlling the flow rate such as a slow leak valve, a mass flow controller, or the like can be used according to the type of the introduced substance.

Using the apparatus shown in FIG. 12, the inside of the envelope 108 is evacuated and forming is performed. At this time, for example, FIG.
As shown in (1), the Y-directional wiring 73 is connected to the common electrode 131, and a voltage pulse is simultaneously applied by the power supply 132 to the electron-emitting devices 74 connected to one of the X-directional wirings 72 to perform forming. be able to. Conditions such as the shape of the pulse and the determination of the end of the processing may be selected according to the above-described forming method.

Further, by sequentially applying (scrolling) a pulse having a shifted phase to the plurality of X-direction wirings 72, the electron-emitting devices 7 connected to the plurality of X-direction wirings 72 are controlled.
4 can be formed together.

In FIG. 13, reference numeral 133 denotes a current measuring resistor;
Reference numeral 4 denotes an oscilloscope for measuring current.

After the forming is completed, an activation step is performed.
After sufficiently exhausting the inside of the envelope 108, an organic substance gas is introduced from the gas introduction line 128. In addition, as described above, first, exhaust may be performed by an oil diffusion pump or a rotary pump, and thereby, an organic substance remaining in a vacuum atmosphere may be used. Furthermore, substances other than organic substances may be introduced as needed.

By applying a voltage to each of the electron-emitting devices 74 in an atmosphere containing an organic substance, carbon or a carbon compound, or a mixture of both, is deposited on the electron-emitting portion. The amount rises drastically as described above. At this time, the voltage may be applied by applying a voltage pulse from the power supply 132 to the electron-emitting devices 74 connected to one of the X-directional wirings 72 in the same connection as in the above-described forming.

After the activation step, it is preferable to perform the stabilization step as described above.

The envelope 108 is heated at 80 to 250 ° C.
While the pressure is kept low, the gas is exhausted through an exhaust pipe 122 by an exhaust device 125 that does not use oil, such as an ion pump or a sorption pump, and the atmosphere is made sufficiently low in organic substances. I will seal it.

[0139] In order to maintain the pressure after sealing the envelope 108, a getter process may be performed. This is because the getter disposed at a predetermined position (not shown) in the envelope 108 is heated by heating using resistance heating or high-frequency heating immediately before or after the envelope 108 is sealed. This is a process for forming a deposited film. Getters
Usually, Ba or the like is a main component, and the atmosphere in the envelope 108 is maintained by the adsorption action of the deposited film.

Next, an example of the configuration of a driving circuit for performing television display based on an NTSC television signal using a display panel configured using electron sources in a simple matrix arrangement will be described with reference to FIG. .

In FIG. 14, reference numeral 141 denotes a display panel;
42 is a scanning circuit, 143 is a control circuit, 144 is a shift register, 14 and 5 are line memories, 146 is a synchronization signal separation circuit, 147 is a modulation signal generator, and Vx and Va are DC voltage sources.

The display panel 141 is connected to an external electric circuit via terminals Dox1 to Doxm, terminals Doy1 to Doyn, and a high voltage terminal Hv.

At the terminals Dox1 to Doxm, electron sources provided in the display panel 141, that is, electron emission element groups arranged in a matrix of m rows and n columns are sequentially driven one row (n element) at a time. Scan signal is applied. To the terminals Doy1 to Doyn, a modulation signal for controlling the output electron beam of each of the electron-emitting devices in one row selected by the scanning signal is applied. The high-voltage terminal Hv is supplied with a DC voltage of, for example, 10 kV from a DC voltage source Va, which is used to apply sufficient energy to the electron beam emitted from the electron-emitting device to excite the phosphor. Acceleration voltage.

The scanning circuit 142 will be described.

The scanning circuit 142 includes m switching elements (symbols S1 to Sm in the drawing). Each switching element is an output voltage of the DC voltage source Vx or 0 V (ground level)
Is selected, and the terminal Do of the display panel 141 is selected.
It is electrically connected to x1 to Doxm. Also,
The switching elements S1 to Sm are connected to the control circuit 14
3 operates based on the control signal Tscan output by the control signal 3 and can be configured by combining switching elements such as FETs.

In the case of the present embodiment, the DC voltage source Vx uses a drive voltage applied to an unscanned electron-emitting device based on the characteristics of the electron-emitting device (electron emission threshold voltage Vth). It is set to output a constant voltage that is equal to or lower than the value voltage Vth.

The control circuit 143 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 143 includes the synchronization signal separation circuit 14
Based on the synchronization signal Tsync sent from the control unit 6, the control unit generates Tscan, Tsft, and Tmry control signals for each unit.

The synchronizing signal separating circuit 146 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 146 includes a vertical synchronizing signal and a horizontal synchronizing signal, but is shown here as a Tsync signal for convenience of explanation. The luminance signal component of the image separated from the television signal is DATA for convenience.
Signaled. The DATA signal is supplied to the shift register 144.
Is input to

The shift register 144 is for serially / parallel converting the DATA signal input serially in time series for each line of an image, and is based on a control signal Tsft sent from the control circuit 143. (Ie, the control signal Tsft can be said to be a shift clock of the shift register 144).
The data of one line of the serial / parallel-converted image (corresponding to drive data for n electron-emitting devices) is Id
The shift register 144 outputs as n parallel signals of 1 to Idn.

The line memory 145 is a storage device for storing data for one line of an image for a necessary time only, and stores the contents of Id1 to Idn as appropriate according to a control signal Tmry sent from the control circuit 143. The stored contents are output as I'd1 to I'dn and input to the modulation signal generator 147.

The modulation signal generator 147 outputs the image data I ′
It is a signal source for appropriately driving and modulating each of the surface conduction electron-emitting devices according to each of d1 to I'dn, and its output signal is sent to the electron-emitting devices in the display panel 141 through terminals Doy1 to Doyn. Applied.

As described above, the electron-emitting device obtained according to the present invention has the following basic characteristics with respect to the emission current Ie.

That is, electron emission has a clear threshold voltage Vth, and electron emission occurs only when a voltage 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 electron emission element.

Therefore, when a pulse-like voltage is applied to the electron-emitting device, for example, even if a voltage lower than the electron emission threshold is applied, no electron emission occurs, but a voltage higher than the electron emission threshold is applied. When applied, an electron beam is output. At that time, the intensity of the output electron beam can be controlled by changing the peak value Vm of the pulse. Further, by changing the pulse width Pw, it is possible to control the total amount of charges of the output electron beam.

Therefore, as a method of modulating the electron-emitting device in accordance with 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 147. be able to. When performing the pulse width modulation method, the modulation signal generator 147 generates a voltage pulse having a constant peak value, and modulates the width of the voltage pulse appropriately according to input data. A circuit can be used.

The shift register 144 and the line memory 14
5 can be either 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, the synchronization signal separation circuit 146
Is required to be converted into a digital signal, which requires an A / D output at the output of the synchronizing signal separation circuit 146.
A converter may be provided.

In connection with this, the circuit used for the modulation signal generator 147 differs slightly depending on whether the output signal of the line memory 145 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 147, and an amplification circuit and the like are added as necessary.

In the case of the pulse width modulation method, the modulation signal generator 147 includes, for example, a high-speed oscillator, a counter for counting the number of waves output from the oscillator, and a comparison between the output value of the counter and the output value of the memory. A circuit in which a comparator (comparator) is combined is used. If necessary, an amplifier for amplifying the pulse width modulated signal output from the comparator to the drive voltage of the electron-emitting device can be added.

In the case of a voltage modulation method using an analog signal, an amplification circuit using, for example, an operational amplifier can be used as the modulation signal generator 147, 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 manufactured according to the present invention, electrons are emitted by applying a voltage to each of the electron-emitting devices via the external terminals Dox1 to Doxm and Doy1 to Doyn. Also, the high voltage terminal H
When a high voltage is applied to the metal back 105 or the transparent electrode (not shown) via v to accelerate the electron beam, the accelerated electrons collide with the fluorescent film 104 and emit light to form an image. .

The input signal has been described in the NTSC system. However, the input signal is not limited to this.
A TV signal (for example, a high-definition TV such as the MUSE system) including a larger number of scanning lines, such as the L and SECAM systems, may be employed.

[0163]

Embodiment 1 The configuration of an electron-emitting device according to this embodiment is the same as the configuration shown in FIG. 1 described above, and its manufacturing method is basically the same as that described with reference to FIG. The same is true.

Hereinafter, a manufacturing method will be described.

Step (a) On a substrate 1 in which a silicon oxide film having a thickness of 1 μm is formed on a cleaned blue plate glass by a CVD method, a pattern to be the element electrodes 4 and 5 facing each other with an element electrode interval L therebetween. To photoresist (“RD-2000N-41” manufactured by Hitachi Chemical Co., Ltd.)
, And 5 nm thick Ti and 100 nm thick Pt were sequentially deposited by a vacuum evaporation method. After this deposition, the photoresist pattern was dissolved with an organic solvent, and the Pt / Ti deposited film was lifted off to form device electrodes 4 and 5 having a device electrode interval L of 10 μm and a device electrode width W of 300 μm (FIG. 3).
(A)).

Step (b) A circular pattern having a diameter W ′ of 100 μm is formed of a photoresist (“RD-2000N-41” manufactured by Hitachi Chemical Co., Ltd.) in order to remove the region where the conductive thin film 3 is formed as the opening 6 a. Almost the entire surface of the substrate 1 was covered with the antistatic film 6 by the method described below.

The antistatic film 6 was formed by RF magnetron sputtering. The target used was tin oxide, and the film thickness was controlled by the sputtering time.
m. Sheet resistance is about 2 × 10 ¹¹ Ω / □
Met.

Next, the photoresist pattern was dissolved with an organic solvent, the antistatic film 6 on the photoresist pattern was lifted off, and a circular opening 6a serving as a region for forming a conductive thin film 3 described later was formed (FIG. b)).

Step (c) After the substrate 1 was washed again and dried, an organic palladium-containing solution (“cpp-4230” manufactured by Okuno Pharmaceutical Co., Ltd.) was
Using a heating type ink jet device as the droplet applying device 7, droplets 8 were applied in the opening 6a (FIG. 3).
(C)). The droplet 8 fills the inside of the opening 6 a where the antistatic film 6 is not formed and is contained in the opening 6 a.
It did not spread irregularly on the top and became a stable shape.

Step (d) Next, a heat treatment is performed at 350 ° C. for 10 minutes to form a fine particle film made of fine particles of palladium oxide (PdO).
The conductive thin film 3 was obtained (FIG. 3D). Film thickness is 10n on average
m and sheet resistance were 5 × 10 ⁴ Ω / □.

The fine particle film described here is a film in which a plurality of fine particles are gathered, and has a fine structure not only in a state where the fine particles are individually dispersed and arranged, but also in a state where the fine particles are adjacent to each other or overlap each other (an island). (Including the shape).

Step (e) Next, the apparatus is set in the measurement and evaluation apparatus shown in FIG.
After evacuating at 6 and reaching a pressure of 2 × 10 ⁻³ Pa, a voltage was applied between the device electrodes 4 and 5 from a power source 51 for applying a device voltage Vf to the electron-emitting device, and energization forming was performed. .

FIG. 4B shows the voltage waveform of the energization forming (forming voltage waveform). In the figure, T1 and T
2 is the pulse width and pulse interval of the voltage waveform, respectively. In this embodiment, T1 is 1 ms, T2 is 10 ms,
Set the peak value (peak voltage during forming) of the triangular wave to 0.
The energization forming was performed by increasing the voltage in 1 V steps. In addition, during the energization forming, a resistance measurement pulse was simultaneously inserted between T2 at a voltage of 0.1 V to measure the resistance.

The energization forming was terminated when the value measured by the resistance measurement pulse became about 1 MΩ or more, and the application of the voltage to the electron-emitting device was terminated at the same time. The forming voltage Vf at the end of the energization forming was 5.0V.

Thereafter, annealing was performed at 200 ° C. while the electron-emitting device was kept in a vacuum, and the conductive thin film 3 including the electron-emitting portion 2 was reduced.

Step (f) Subsequently, an acetone-sealed ampoule was introduced into a vacuum through a slow leak valve to maintain 0.1 Pa. (Not shown) Next, activation processing was performed on the electron-emitting device subjected to the energization forming with the waveform of FIG.
This activation process was performed by applying the pulse voltage between the device electrodes 4 and 5 while measuring the device current If and the emission current Ie in the measurement and evaluation device shown in FIG.

The efficiency η ((Ie / If) × 100%) is
Since the maximum was reached in about 30 minutes, the energization was stopped, the slow leak valve was closed, and the activation process was completed.

Thereafter, in order to perform a stabilization process, the inside of the vacuum vessel is evacuated to 1 × 10 ⁻⁵ Pa, the substrate on which the electron-emitting devices are formed is heated at 300 ° C., and the vacuum vessel is heated at 250 ° C.
For 10 hours at the same time.

Step (g) An electron-emitting device was manufactured by forming the electron-emitting portion 2 in this way, and the electron-emitting characteristics were evaluated. The evaluation was performed on the anode 5
4 and the distance between the electron-emitting device and the anode 54
Was set to 5 kV, and the pressure in the vacuum vessel 55 at the time of measuring the electron emission characteristics was set to 1 × 10 ⁻⁶ Pa.

An element voltage Vf of 14 is applied between the element electrodes 4 and 5.
When V was applied, the electron emission characteristics were extremely stable, and no destruction of the electron emission element due to discharge or the like occurred.

Example 2 A plurality of electron-emitting devices having the structure shown in FIG. 1 were arranged on a substrate as schematically shown in FIGS. 8 and 9, and an electron source in which matrix wirings were arranged was used in the following procedure. Created by

[Step 1] A substrate 1 having a silicon oxide film having a thickness of 1 μm formed on a blue plate glass by a CVD method is washed with a detergent and pure water, and then the device electrodes 4 and 5 opposed to each other with a device electrode interval L therebetween. The pattern to be formed is formed by photoresist (“RD-2000N-41” manufactured by Hitachi Chemical Co., Ltd.), and 5 nm thick Ti and 100 nm thick P are formed by vacuum evaporation.
t were sequentially deposited. After this deposition, the photoresist pattern was dissolved with an organic solvent, the Pt / Ti deposited film was lifted off, and the element electrode interval L was 20 μm and the element electrode width W was 200 μm.
μm device electrodes 4 and 5 were formed (FIG. 9A).

[Step 2] Next, a paste material containing Ag as a metal component (“NP-4028” manufactured by Noritake Co., Ltd.)
A ") and the Y-directional wiring 72 by screen printing.
After drying, the paste is dried at 110 ° C. for 20 minutes, and then baked by a heat treatment apparatus at a peak temperature of 580 ° C. and a peak holding time of 8 minutes.
The direction wiring 72 was formed (FIG. 9B).

[Step 3] Next, using a paste containing PbO as a main component, a pattern of the interlayer insulating layer 81 is printed.
Firing was performed under the same conditions as in Step 2 to form an interlayer insulating layer 81 (FIG. 9C). This interlayer insulating layer 81 was arranged at the intersection of the X-directional wiring 73 and the Y-directional wiring 72.

[Step 4] X-directional wiring 73 was formed in the same manner as in step 2 (FIG. 9D).

[Step 5] In order to remove the region where the conductive thin film 3 is formed as the opening 6a, a circular pattern having a diameter W ′ of 100 μm was formed using a photoresist (“RD-2” manufactured by Hitachi Chemical Co., Ltd.).
000N-41 "), and the substantially entire surface of the substrate 1 was covered with the antistatic film 6 by the method described below.

The antistatic film 6 was formed by RF magnetron sputtering. The target used was tin oxide, and the film thickness was controlled by the sputtering time.
m. Sheet resistance is about 2 × 10 ¹¹ Ω / □
Next, the photoresist pattern was dissolved with an organic solvent, and the antistatic film 6 on the photoresist pattern was lifted off.
A circular opening 6a to be a region for forming a conductive thin film 3 described later was formed (FIG. 9E).

In this embodiment, the conductive thin film 3
Although the antistatic film 6 is formed on almost the entire surface except for the opening 6a for forming the wiring, as described above, for example, the X-direction wiring 73 and the Y-direction wiring 72 are not charged because they are conductors. Does not require the antistatic film 6, the X-directional wiring 73 and the Y-directional wiring 72 may be lifted off at the same time so that the antistatic film 6 is not formed.

[Step 6] Next, a conductive thin film 3 was formed.

Specifically, an organic palladium-containing solution (“cpp-4230” manufactured by Okuno Pharmaceutical Co., Ltd.) was added to the droplet applying device
Was applied as droplets 8 in the openings 6a using a heating type inkjet apparatus. The droplet is charged by the antistatic film 6
Is filled in the opening 6a where the opening 6a is not formed.
Inside the substrate 1 and did not spread in an irregular shape on the substrate 1, and became a stable shape.

Thereafter, a heat treatment was performed at 350 ° C. for 10 minutes to obtain a fine particle film composed of fine palladium oxide particles (FIG. 9F).

The steps after the forming were performed after the envelope was formed, as described below.

Next, an image forming apparatus was prepared by using the electron source prepared as described above. The procedure will be described with reference to FIGS.

After the base 1 provided with a large number of electron-emitting devices is fixed on the rear plate 101 as described above, the face plate 106 (the inner surface of the glass base 103 and the fluorescent film 104 And metal back 10
5) is disposed via the support frame 102,
Frit glass is applied to the joint between the face plate 106, the support frame 102, and the rear plate 101, and to the joint between the rear plate 101 and the base 1, and 400 ° C. in a nitrogen atmosphere.
Sealing was performed by baking at 500 to 500 ° C. for 10 minutes or more (FIG. 10).

The rear plate 101, the support frame 102
The face plate 106 was formed of soda lime glass of the same material as the base 1.

As the fluorescent film 104, a matrix shape was adopted, a black matrix was formed first, and the phosphors 112 of each color were applied to the gaps, thereby forming the fluorescent film 104. As a material of the black conductive material 111 constituting the black matrix, a commonly used material mainly containing graphite was used. A slurry method was used as a method for applying the phosphor 112 to the glass substrate 103.

Further, a metal back 105 was provided on the inner surface side of the fluorescent film 104. The metal back 105 is the fluorescent film 1
After the production of the phosphor film 104, the inner surface of the fluorescent film 104 is subjected to a smoothing treatment (usually called filming),
Was produced by vacuum evaporation.

In the face plate 106, a transparent electrode (not shown) may be provided on the outer surface side of the fluorescent film 104 in order to further increase the conductivity of the fluorescent film 104. In this embodiment, only the metal back 105 is provided. Was omitted because sufficient conductivity was obtained.

At the time of performing the above-mentioned sealing, in the case of color, since the phosphors 112 of each color must correspond to the electron-emitting devices, sufficient alignment was performed.

The envelope 108 completed as described above
Is connected to the device shown in FIG. 12, and the atmosphere in the envelope 108 is exhausted by the exhaust device 125 through the exhaust pipe 122,
After reaching a sufficient pressure, as shown in FIG. 13, a voltage is applied between the electrodes 4 and 5 of the electron-emitting device 74 through the external terminals Dxo1 to Doxm and Doy1 to Doyn to form the conductive thin film 3. By performing the treatment, the electron-emitting portion 2 was formed.

The voltage waveform of the forming process is shown in FIG.
Same as (b). In this embodiment, T1 is 1 ms, T2
Was set to 10 ms and the pressure was about 2 × 10 ⁻³ Pa.

In the electron-emitting portion 2 thus prepared, fine particles mainly composed of palladium were dispersed and arranged, and the average particle size of the fine particles was 3 nm.

Next, acetone was passed through the exhaust pipe of the panel.
Introduced into the panel through a slow leak valve, 0.1
Pa was maintained.

Next, the triangular wave used in the above-described forming process is changed to a rectangular wave, and a wave height of 14 V and an element current I
f, the activation process was performed while measuring the emission current Ie.

As described above, the forming and activating processes were performed to form the electron-emitting portion 2, and the electron-emitting device 74 was manufactured.

Next, the envelope was evacuated from the vicinity of the envelope to a pressure of about 10 ⁻⁶ Pa while heating the envelope to 300 ° C. for 10 hours, and the exhaust pipe was welded by heating with a gas burner. Was sealed. Finally, in order to maintain the degree of vacuum after sealing, getter processing was performed by a high-frequency heating method.

In the image display device of the present embodiment completed as described above, each of the electron-emitting devices has a terminal Dx1 outside the container.
The scanning signal and the modulation signal are applied from signal generation means (not shown) through Dxm, Dy1 to Dyn, respectively, thereby emitting electrons, and through the high voltage terminal Hv, the metal back 105 or a transparent electrode (not shown).
An image was displayed by applying a high voltage of several kV or more to accelerate the electron beam and causing it to collide with the fluorescent film 104 to excite and emit light.

In this embodiment, the antistatic film 6 is also formed on the insulating surface on the interlayer insulating layer 81,
This portion is also effectively prevented from being charged.

As a result, a stable image was displayed, no abnormal deflection of the electron beam occurred, and no destruction due to electric discharge was observed.

[0210]

As described above, in the present invention, the antistatic film is formed by removing the portion where the conductive thin film including the electron-emitting portion is formed as an opening, and the liquid anti-static method is used in the opening. In order to form a conductive thin film, the periphery of the opening of the antistatic film functions as a weir when the droplet is applied, and the droplet does not spread in an irregular shape on the substrate. Without conducting the hydrophobic treatment, the uniformity of the shape and thickness of the conductive thin film can be improved. Therefore, since the surface treatment of the base is not required, it is possible to shorten the steps and the processing time.

Further, since the shape of the conductive thin film matches the opening of the antistatic film, the reproducibility and uniformity of the dimensions of the conductive thin film can be improved, and the electron in which a plurality of electron-emitting devices are formed is formed. When forming an image display device using a source,
It is possible to improve the reproducibility and uniformity of the entire display,
By applying the present invention to an image forming apparatus, image quality can be improved.

[Brief description of the drawings]

FIG. 1 is a basic configuration diagram of an electron-emitting device obtained by the present invention.

FIG. 2 is another configuration diagram of the electron-emitting device obtained by the present invention.

FIG. 3 is a manufacturing process diagram of the conduction electron-emitting device shown in FIG.

FIG. 4 is a diagram illustrating an example of a forming voltage waveform.

FIG. 5 is an explanatory diagram of an apparatus for measuring and evaluating characteristics of an electron-emitting device.

FIG. 6 is a schematic diagram showing the relationship between the emission current Ie, the device current If, and the device voltage Vf of the electron-emitting device obtained by the present invention.

FIG. 7 is a schematic configuration diagram of a basic configuration of an electron source.

FIG. 8 is a plan view illustrating a configuration of an electron source obtained by the present invention.

FIG. 9 is a schematic view illustrating a manufacturing process of the electron source of FIG. 8;

FIG. 10 is a perspective view showing a schematic configuration of a display panel using the electron source of FIG.

FIG. 11 is an explanatory diagram of a fluorescent film.

FIG. 12 is a schematic diagram of a vacuum exhaust device for performing an electron emitting portion forming step and an activation step when manufacturing an electron source and an image forming apparatus.

FIG. 13 is an explanatory diagram of a wiring state for performing an electron emission portion forming step and an activation step when manufacturing an electron source and an image forming apparatus.

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Electron emission part 3 Conductive thin film 4 Element electrode 5 Element electrode 6 Antistatic film 6a Opening 7 Droplet applying device 8 Droplet 50 Ammeter 51 Power supply 52 Ammeter 53 High voltage power supply 54 Anode electrode 55 Vacuum container 56 Exhaust Pump 72 X-directional wiring 73 Y-directional wiring 74 Electron-emitting device 75 Connection 81 Interlayer insulating layer 101 Rear plate 102 Support frame 103 Base 104 Fluorescent film 105 Metal back 106 Face plate 108 Enclosure 111 Black conductive material 112 Phosphor 121 Display panel 122 Exhaust pipe 123 Vacuum chamber 124 Gate valve 125 Exhaust device 126 Pressure gauge 127 Quadrupole mass analyzer 128 Gas introduction line 129 Introduced amount control means 130 Introduced substance source 131 Common electrode 132 Power supply 133 Current measuring resistor 134 Oscilloscope 1 41 display panel 142 scanning circuit 143 control circuit 144 shift register 145 line memory 146 synchronization signal separation circuit 147 modulation signal generator Vx and Va DC voltage source

Claims (6)

[Claims] An element electrode forming step of providing a pair of opposing element electrodes on an insulating substrate; a conductive thin film forming step of providing conductive thin films respectively connected to the pair of element electrodes; An electron-emitting portion forming step of forming an electron-emitting portion on a part of the conductive thin film, wherein at least prior to the conductive thin-film forming step, the conductive thin film is formed in the conductive thin-film forming step. An antistatic film forming step of providing an antistatic film on the substrate except for a region provided as an opening, and the conductive thin film forming step is provided on the substrate in the antistatic film forming step. A method for manufacturing an electron-emitting device, comprising a step of applying a liquid containing a conductive thin film component as droplets in an opening of an antistatic film. 2. An antistatic film forming step and a conductive thin film forming step are performed after an element electrode forming step, and in the antistatic film forming step, opposite ends of a pair of element electrodes provided in the element electrode forming step. 2. The method for manufacturing an electron-emitting device according to claim 1, wherein the step of forming the conductive thin film is performed after the portion is positioned in the opening and the antistatic film is provided on the pair of device electrodes. 3. An antistatic film forming step and a conductive thin film forming step are performed before an element electrode forming step, and a conductive thin film is formed in the opening of the antistatic film provided in the antistatic film forming step by the conductive thin film forming step. Is provided, in the device electrode forming step,
2. The method according to claim 1, wherein an element electrode is provided on a conductive thin film provided in an opening of the antistatic film. 4. The method according to claim 1, wherein the application of the conductive thin film component-containing liquid as droplets in the conductive film forming step is performed by an ink jet device that discharges the droplets by a pressure of a piezoelectric element or a pressure of bubbles generated by heating. The method for manufacturing an electron-emitting device according to claim 1. 5. A method for manufacturing an electron source, comprising forming a plurality of electron-emitting devices on a common substrate by the method for manufacturing an electron-emitting device according to claim 1. 6. An image forming apparatus, wherein an electron source manufactured by the method for manufacturing an electron source according to claim 5 is combined with an image forming member that forms an image by irradiating an electron beam from the electron source. Manufacturing method.