JPH1040805A - Cold-cathode element and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cold-cathode element for the efficient generation of electron beams by constituting a cold-cathode part which includes a structure designed to serve as several electron emission sources. SOLUTION: This cold-cathode element comprises a conductive layer 2, a cold-cathode part 3 formed thereon, and a gate electrode 3 for taking electrons out of the cold-cathode part 3. In this case, the cold-cathode part 3 includes a structure designed to serve as several electron emission sources. By introducing a process of distributing granular diamonds having an average grain diameter, not greater than about 0.2μm over the conductive layer 2, or a process of implanting granular diamonds having an average grain diameter not greater than about 0.2μm into the conductive layer 2, diamonds highly suitable for cold-cathode material can be arranged on the conductive layer 2 or the surface layer thereof so as to be easily reproduced, in the form of minute grains or its aggregate to provide a structure, designed to serve as electron emission sources. Thus, it is possible to simply produce a highly efficient cold-cathode element.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cold cathode device which emits an electron beam, and more particularly to a cold cathode device comprising a cold cathode portion having particulate diamond as an electron emission source and a method of manufacturing the same.

[0002]

2. Description of the Related Art Micron-sized micro-electron-emitting devices have attracted attention as an electron beam source in place of an electron gun for a high-definition thin display or as an emitter of a micro vacuum device capable of high-speed operation. Conventionally, as the electron-emitting device, a heat-emitting device that applies a voltage of several kilovolts or more to a material such as tungsten (W) heated to a high temperature has been used. 2. Description of the Related Art Cold cathode electron-emitting devices capable of emitting electrons even at a high voltage have been actively researched and developed from the viewpoint of low power consumption.

[0003] There are various types of such cold cathode devices, but in general, field emission type devices and p-type devices are known.
An avalanche amplification type using n and Schottky junctions has been reported. A field emission type cold cathode device is a cone-shaped tip made of high melting point metal such as silicon (Si) or molybdenum (Mo) by applying a voltage to the gate electrode and applying an electric field to the cold cathode. It emits electrons from a part, and has features such as downsizing and integration by using microfabrication technology. In the avalanche amplification type using a semiconductor material, a reverse bias voltage is applied to a pn and a Schottky junction to cause avalanche amplification, so that electrons are hot and electrons are emitted from an emitter.

[0004]

The characteristics generally required for a cold cathode device include the fact that electrons can be emitted with low power and the obtained current has good stability. For that purpose, it is necessary to properly select the structure of the cold cathode portion, which is mainly an electron emission source, and the material to be used.

The structure of the electron emission portion of the field emission type cold cathode device manufactured so far has a cone shape having a single sharp projection called a Spindt type. Heavily relied on. Materials used for the cold cathode device include (1) easy emission of electrons in a relatively small electric field, that is, low electron affinity of the substance, and (2) maintenance of stable electron emission characteristics. Although the emitter surface is chemically stable and (3) it is excellent in wear resistance and heat resistance, none of the conventional materials satisfy all of these requirements. In other words, when the prior art is viewed from the above viewpoints, the field emission device has a large dependence of the emission current on the shape of the emitter portion, making it very difficult to manufacture and control the device. There were issues in terms of stability. Further, in this method, each element is an electron emission source at a point from the cone-shaped tip portion where the electric field is concentrated, and it is difficult to obtain a planar electron emission flow from which a large current can be taken out.

Further, avalanche-amplified cold cathode devices generally need to apply a very large amount of current to the device, so that the device generates heat, which causes unstable electron emission characteristics and shortens the life of the device. There was a problem that In the avalanche amplification type, the work function amount of the electron emission portion is reduced by providing a cesium layer or the like on the surface of the emitter, but a material having a small work function such as cesium has a chemically unstable surface state. There is also a problem that it is not stable, that is, the electron emission characteristics are not stable. As described above, the materials and structures used so far do not sufficiently satisfy the characteristics required for the electron-emitting device.

In order to solve the above-mentioned problems in the prior art, the present invention has a structure in which a cold cathode portion includes a structure that can serve as a plurality of electron emission sources, so that the cold cathode efficiently emits an electron beam. It is intended to provide an element.

In the present invention, the distance between the conductive layer and the gate electrode for extracting electrons from the cold cathode portion is 0.5 μm or less, or the area of the opening of the cold cathode portion is 2 × 10 ⁻⁹ cm ² or less. It is an object of the present invention to provide a fine and highly efficient cold cathode device by including the configuration.

In the method of the present invention, diamond particles having an average particle diameter of 0.2 μm or less are distributed on the conductive layer, or the diamond particles having an average particle diameter of 0.2 μm or less are embedded in the conductive layer. It is an object of the present invention to provide a method for easily manufacturing a cold cathode device that efficiently emits an electron beam by including a step.

In addition, the method of the present invention makes it possible to easily and rationally control a manufacturing process important for manufacturing a high-efficiency electron-emitting device having a particulate diamond disposed in a cold cathode portion, and a surface state control of the particulate diamond. It is intended to provide a method for performing the method.

[0011]

In order to achieve the above object, a cold cathode device according to the present invention comprises a conductive layer, a cold cathode portion formed on the conductive layer, and an electron beam from the cold cathode portion. A cold cathode element provided with a gate electrode for extracting the electrons, wherein the cold cathode portion has a structure including a structure that can serve as a plurality of electron emission sources.

In order to achieve the above object, a cold cathode device according to the present invention comprises a conductive layer, a cold cathode portion formed on the conductive layer, and a gate for extracting electrons from the cold cathode portion. A cold cathode device comprising an electrode and a structure including a cold cathode portion including a structure that can serve as a plurality of electron emission sources, and a diaphragm electrode for controlling the trajectory of the extracted electrons. And

Further, in the present invention, in the above-mentioned element structure, it is preferable that a structure which can be a plurality of electron emission sources arranged in the cold cathode portion is arranged on the conductive layer.

Further, in the present invention, it is preferable that in the device structure, a structure which can be a plurality of electron emission sources arranged in the cold cathode portion is embedded in the surface layer of the conductive layer.

Further, in the present invention, in the above-mentioned element structure, it is preferable that a conductive layer on which a plurality of structures capable of serving as an electron emission source are arranged in the cold cathode portion is flat.

Further, in the present invention, it is preferable that in the device structure, a structure that can be a plurality of electron emission sources disposed in the cold cathode portion is isolated.

Further, in the present invention, it is preferable that in the device configuration, the structure that can be a plurality of electron emission sources disposed in the cold cathode portion is a particle or an aggregate of particles.

Further, in the present invention, in the above-mentioned element structure, it is preferable that the average particle diameter of the particles arranged in the cold cathode portion is 0.2 μm or less. More preferably, the average particle size of the particles is 0.05 μm or less.

Further, according to the present invention, in the above-mentioned element structure, the distribution density of particles or aggregates of particles arranged in the cold cathode portion is at least 1 × 10 3 per square centimeter.
^The number is preferably ¹⁰ or more. More preferably, the distribution density of particles or agglomerates of particles is 1 × 10 ¹¹ or more per square centimeter.

In the present invention, it is preferable that in the device structure, a structure that can be a plurality of electron emission sources disposed in the cold cathode portion is made of diamond.

According to the present invention, in the above-mentioned device structure, the surface of the diamond disposed on the cold cathode portion may be, for example, cesium (Cs), nickel (Ni), titanium (Ti), tungsten (W), hydrogen (H). It is preferable to include a configuration coated with amorphous carbon or the like.

According to the present invention, in the above-mentioned element structure, it is preferable that a substance covering a surface of the diamond disposed on the cold cathode portion has an attached atom density of 1 × 10 ¹⁷ or less per square centimeter. More preferably, the coating material has an attached atom density of 1 × 10 ¹⁶ or less per square centimeter.

Further, the present invention preferably has a structure in which the carbon atoms on the outermost surface of the diamond arranged in the cold cathode portion are terminated by bonding with hydrogen atoms in the above-mentioned element structure.

Further, in the present invention, in the above-mentioned device configuration, the amount of hydrogen atoms bonded to carbon atoms on the outermost surface of the diamond arranged in the cold cathode portion is preferably 1 × 10 ¹⁵ or more per square centimeter. . More preferably, the amount of hydrogen bonded to carbon atoms on the outermost surface of diamond is 2 × 10 ¹⁵ atoms / cm ² or more.

Further, according to the present invention, in the above-mentioned element structure, it is preferable that the conductive layer has a multilayer structure including at least one semiconductor layer.

In order to achieve the above object, a cold cathode device according to the present invention comprises a conductive layer, a cold cathode portion formed on the conductive layer, and a gate for extracting electrons from the cold cathode portion. A cold cathode device including an electrode, wherein a distance between the conductive layer and the gate electrode is 0.5 μm or less.

In order to achieve the above object, a cold cathode device according to the present invention comprises a conductive layer, a cold cathode portion formed on the conductive layer, and a gate for extracting electrons from the cold cathode portion. A cold cathode element comprising an electrode and an opening area of the cold cathode portion is 2 × 10 ⁻⁹ cm ² or less.

Further, in order to achieve the above object, a conductive layer according to the present invention, a cold cathode portion formed on the conductive layer,
A method of manufacturing a cold cathode device including a gate electrode for extracting electrons from the cold cathode portion has an average particle size of 0.2 μm
The method includes a step of distributing the following particulate diamond on the conductive layer.

In order to achieve the above object, a method of manufacturing a cold cathode device according to the present invention comprises a step of distributing a diamond having an average particle diameter of 0.2 μm or less on the conductive layer; Growing a diamond layer on the diamond.

In order to achieve the above object, a method of manufacturing a cold cathode device according to the present invention includes a step of embedding particulate diamond having an average particle size of 0.2 μm or less in the conductive layer. .

According to another aspect of the present invention, there is provided a method of manufacturing a cold cathode device, comprising the steps of: embedding particulate diamond having an average particle size of 0.2 μm or less in the conductive layer; Growing a diamond layer on the substrate.

In the present invention, it is preferable that the step of growing a diamond layer on the particulate diamond is a vapor phase synthesis method.

In the present invention, the step of arranging the particulate diamond on the conductive layer or the surface of the conductive layer may be performed after the step of forming the insulator layer in a partial region on the base material. Is preferred.

In the present invention, the step of disposing the particulate diamond on the conductive layer or on the surface of the conductive layer is preferably performed after the step of forming the gate electrode.

Further, in the present invention, in the above-mentioned production method, the method for arranging the particulate diamond on the conductive layer or on the surface of the conductive layer may be such that a solution in which particulate diamond having an average particle diameter of 0.2 μm or less is dispersed is used as a base material. It is preferably applied to More preferably, the average particle size of the particulate diamond used is 0.05 μm or less.

[0036] In the present invention, the method for arranging the particulate diamond on the conductive layer or on the surface of the conductive layer may be based on a solution in which particulate diamond having an average particle diameter of 0.2 μm or less is dispersed. It is preferable to install a material and apply ultrasonic vibration to the solution. More preferably, the average particle size of the particulate diamond used is 0.05 μm or less.

Further, in the present invention, in the above-mentioned manufacturing method, the method of arranging the particulate diamond on the conductive layer or on the surface of the conductive layer is preferably a method in which a particulate diamond having an average particle diameter of 0.2 μm or less is dispersed in a solution. It is preferable that a material is installed and a voltage is applied between the conductive part of the base material and the container containing the solution, or between the conductive part of the base material and the electrode provided in the solution. More preferably, the average particle size of the particulate diamond used is 0.05 μm or less.

According to the present invention, in the above-mentioned production method, the amount of the particulate diamond dispersed in the solution in which the substrate is provided is preferably 0.01 g or more and 100 g or less per liter of the solution.

More preferably, the amount of the particulate diamond is from 0.1 g to 20 g per liter of the solution.

Further, according to the present invention, in the above-mentioned production method, the number of particulate diamonds dispersed in the solution in which the base material is placed is 1 × 10 ¹⁶ or more per 1 liter of the solution.
^The number is preferably ²⁰ or less. More preferably, the number of particulate diamonds dispersed in the solution is 1 × 10 ¹⁷ or more and 1 × 10 ¹⁹ or less per liter of the solution.

Further, in the present invention, in the above-mentioned production method, it is preferable that the solution in which the base material is placed contains water or alcohol as a main component.

According to the present invention, in the above-mentioned production method, it is preferable that the solution in which the base material is provided contains at least a compound containing fluorine (F) as a constituent element. More preferably, the compound containing fluorine (F) as a constituent element is hydrofluoric acid or ammonium fluoride.

Further, according to the present invention, in the above-mentioned manufacturing method, the distribution density of the particulate diamond disposed on the conductive layer or on the surface of the conductive layer is 1 × 10 3 / cm 2.
^The number is preferably ¹⁰ or more. More preferably, the distribution density is 1 × 10 ¹¹ or more per square centimeter.

In order to achieve the above object, a method of manufacturing a cold cathode device according to the present invention includes a step of irradiating a predetermined region of the particulate diamond arranged in the cold cathode portion with vacuum ultraviolet light having a wavelength of 200 nm or less. It is characterized by including.

In order to achieve the above object, a method for manufacturing a cold cathode device according to the present invention is obtained by subjecting a predetermined region of particulate diamond arranged in a cold cathode portion to discharge decomposition of a gas containing at least hydrogen. A step of exposing to plasma.

In order to achieve the above object, a method of manufacturing a cold cathode device according to the present invention is characterized in that the method includes a step of exposing particulate diamond arranged in a cold cathode portion to a gas containing at least hydrogen.

In order to achieve the above object, a method for manufacturing a cold cathode device according to the present invention is obtained by subjecting a predetermined region of particulate diamond arranged in a cold cathode portion to discharge decomposition of a gas containing at least oxygen. A step of exposing to plasma.

In order to achieve the above object, a method of manufacturing a cold cathode device according to the present invention is characterized in that the method includes a step of exposing particulate diamond disposed at the cold cathode portion to a gas containing at least oxygen.

According to the structure of the present invention, there is provided a cold cathode device including a conductive layer, a cold cathode portion formed on the conductive layer, and a gate electrode for extracting electrons from the cold cathode portion. Since the cold cathode portion has a structure including a plurality of electron emission sources, the following effects can be obtained.

[0050]

FIG. 1 is a sectional view showing a basic structure of a cold cathode device according to the present invention. As shown in FIG. 1, the present cold cathode device includes, as main components, a base material 1, a conductive layer 2 serving as a cathode-side electrode, a cold cathode portion 3, an insulator layer 4, and a cold cathode portion. A gate electrode 5 for extracting electrons. Here, the cold cathode portion 3 is composed of a structure 6 that can be a plurality of electron emission sources.
FIG. 4 shows a structural diagram by a micrograph of the surface of the structure serving as an electron emission source.

FIG. 2 shows, as a comparative example, a conventional structure (Spindt type) of a cold cathode device having similar components.

In any structure, the materials and forming methods used for the base 1, the conductive layer 2, the insulator layer 4, and the gate electrode 5 are common, and are not particularly limited.
For example, the material of the substrate 1 is generally glass or silicon. The conductive layer 2 functions as a lower electrode layer for supplying electrons to the cold cathode portion 3, and may be composed of only a normal metal layer and a low resistance layer,
May be a laminated structure of a resistor layer and a metal layer or a low resistance layer for the purpose of controlling the current supplied to the substrate.

When the base material itself is conductive, it can be omitted. The insulator layer 4 is for electrically separating the cold cathode portion 3 from the gate electrode 5, and is generally made of a silicon dioxide film or a silicon nitride film. The gate electrode 5 is generally made of molybdenum (Mo)
Or a metal such as aluminum (Al).

When comparing FIG. 1 with FIG. 2, the configuration of the cold cathode portion 3 is greatly different. Generally, electrons are emitted from the cold cathode portion 3 by an electric field formed by a voltage applied to the gate electrode 5. The electron emission portion is a portion where the electric field is concentrated most. In the case of the conventional structure as shown in FIG. The electron emission characteristics largely depend on the shape and surface condition of the tip of the cold cathode portion 3 as described above. On the other hand, in the configuration of the present invention as shown in FIG. 1, the electric field applied by the gate electrode 5 is uniformly applied to the structure 6 which can be a plurality of electron emission sources, so that the electron Is emitted, so that a larger electron emission current can be obtained as compared with the case of a single electron emission source, and it is possible to obtain electron emission characteristics with high overall stability. Structure 6 that can be an electron emission source here
Examples thereof include a particle structure described below, an aggregate thereof, and a fine projection structure. However, the structure is not particularly limited as long as the structure easily concentrates an electric field or easily emits electrons.

According to the structure of the present invention, there is provided a cold cathode device including a conductive layer, a cold cathode portion formed on the conductive layer, and a gate electrode for extracting electrons from the cold cathode portion. Therefore, in order to have a configuration including a cold cathode portion including a structure that can be a plurality of electron emission sources, and a diaphragm electrode for controlling the trajectory of the extracted electrons,
The following effects can be obtained.

FIG. 3 is a sectional view showing the basic structure of a cold cathode device according to the present invention. The main components of the present cold cathode device are exactly the same as those of FIG. 1 except for the aperture electrode 7 for controlling the trajectory of the extracted electrons. With such a configuration, the trajectory of the electron flow emitted from the cold cathode portion having a structure that can be a plurality of electron emission sources can be controlled by the aperture electrode 7. That is, it is possible to focus the electron flow or change the trajectory of the electron flow.

In the structure of the present invention, a structure which can be a plurality of electron emission sources arranged in the cold cathode portion is as follows.
According to a preferred example of being disposed on the conductive layer or embedded in the conductive layer surface layer, it is possible to easily form a desired cold cathode device structure.

According to a preferred embodiment of the present invention, the conductive layer for arranging a plurality of structures capable of serving as an electron emission source arranged in the cold cathode portion is flat.
The cold cathode device can be formed without performing a complicated process such as etching which has been conventionally performed.

According to the preferred embodiment of the present invention, in which the structure which can be a plurality of electron emission sources disposed in the cold cathode portion is isolated, the structure which becomes the electron emission source is formed in the cold cathode portion. It is possible to control and arrange at any position.

Further, in the structure of the present invention, according to a preferred example in which the structure that can serve as a plurality of electron emission sources is in the form of particles or agglomerates of particles, it can be formed in any region of the cold cathode portion at any density. It becomes possible to easily arrange the high-efficiency electron emission sources as described above.

According to the preferred embodiment of the present invention, in which the average particle diameter of the particles arranged in the cold cathode portion is 0.2 μm or less, a large number of fine electron emission sources of 0.2 μm or less are provided. , It is possible to efficiently emit electrons and reduce the element size.

According to the preferred embodiment of the present invention, the distribution density of particles or agglomerates of particles arranged in the cold cathode portion is at least 1 × 10 ¹⁰ per square centimeter or more. Since a large number of easy micro electron emission sources are arranged in the cold cathode portion, it is possible to easily obtain a large electron emission.

According to the preferred embodiment of the present invention, wherein the structure which can be a plurality of electron emission sources disposed in the cold cathode portion is diamond, diamond is a wide bandgap semiconductor (5.5 eV), Since it has properties such as high hardness, abrasion resistance, high thermal conductivity, and chemical inertness, it is very suitable as a cold cathode material, and it is possible to realize a cold cathode device that can be driven at low voltage and has high stability. It becomes possible.

In the structure of the present invention, the surface of the diamond disposed on the cold cathode portion is, for example, cesium (Cs), nickel (Ni), titanium (Ti), tungsten (W), hydrogen (H), amorphous (H). According to a preferred example including a configuration coated with carbon or the like, it becomes possible to maintain a diamond surface more stable against electron emission. More preferably, from the viewpoint of not impairing the excellent electron emission properties of diamond, the substance that coats the surface of diamond has an attached atom density of 1 × 10 ¹⁷ or less per square centimeter.

According to the preferred embodiment of the present invention, the carbon atoms on the outermost surface of the diamond disposed in the cold cathode portion include a structure terminated by bonding to hydrogen atoms. Since the diamond surface thus formed has a negative electron affinity state, it becomes possible to make the electron emission source very easy to emit electrons. Further, in the constitution of the present invention, the amount of hydrogen atoms bonded to carbon atoms on the outermost surface of diamond is 1 × 10 ¹⁵ or more, preferably 2 × 10 ¹⁵ per square centimeter.
According to a preferred example of 10 ¹⁵ atoms / cm ² or more, almost all the outermost surface carbon atoms are bonded to hydrogen atoms, so that a more stable negative electron affinity state can be maintained.

According to the preferred embodiment of the present invention, in which the conductive layer has a multilayer structure including at least one semiconductor layer, the amount of current flowing through the cold cathode device can be controlled by the inserted semiconductor layer. In addition, it is possible to prevent discharge of the gate electrode and the cold cathode portion.

According to the structure of the present invention, there is provided a cold cathode device including a conductive layer, a cold cathode portion formed on the conductive layer, and a gate electrode for extracting electrons from the cold cathode portion. The distance between the conductive layer and the gate electrode is
The present invention is characterized by including a configuration of 0.5 μm or less, or a configuration in which the area of the opening of the cold cathode portion is 2 × 10 ⁻⁹ cm ² or less, so that the following effects can be obtained. As described above, when the minute electron emission source is disposed in the cold cathode portion, the distance between the conductive layer portion and the gate electrode can be reduced as compared with the related art. Further, since a plurality of electron emission sources are arranged, a sufficient amount of electron emission can be obtained even in a minute region. That is, it is possible to manufacture a cold cathode device having characteristics equal to or greater than a conventional device at a smaller distance and area than a conventional device, and thus it is possible to manufacture a small cold cathode device having higher integration.

According to the method of the present invention, the conductive layer comprises:
A method of manufacturing a cold cathode element including a cold cathode portion formed on the conductive layer and a gate electrode for extracting electrons from the cold cathode portion, wherein the average particle size is 0.2 μm or less. The step of distributing diamond on the conductive layer, or the step of embedding a particulate diamond having an average particle diameter of 0.2 μm or less in the conductive layer is characterized by the following effects. it can. In other words, diamond, which is very suitable as a cold cathode material, can be arranged on the conductive layer or on the surface of the conductive layer in a reproducible manner in the form of fine particles or aggregates of the structure that can be an electron emission source, so that high efficiency can be easily achieved. A cold cathode device can be formed. Further, with the diamond particles arranged on the conductive layer or on the surface of the conductive layer as nuclei,
Similar effects can be obtained by a structure in which a diamond layer is grown. A sufficient effect can be obtained by setting the average particle diameter of the particulate diamond used to 0.2 μm or less as described above, but the smaller the better, the better. The average particle diameter is desirably 0.02 μm or less.

According to the preferred embodiment of the method of the present invention, wherein the step of growing a diamond layer on diamond particles is a vapor phase synthesis method, fine diamond particles of high quality can be easily obtained.

In the method of the present invention, the step of arranging the particulate diamond on the conductive layer or the surface of the conductive layer is after the step of forming the insulator layer in a partial region on the base material, or the step of forming the gate electrode. According to a preferred example, which is after the step of forming, the process of manufacturing a high-efficiency cold-cathode device becomes easy, for example, the arrangement of diamond particles in the cold-cathode portion becomes self-aligned.

In the method of the present invention, the method of distributing particles on the substrate material or on the surface of the substrate material is to apply a solution in which particulate diamond having an average particle size of 0.2 μm or less is dispersed to the substrate, or The substrate material is placed in a solution in which particulate diamond having an average particle size of 0.2 μm or less is dispersed, and ultrasonic vibration is applied to the solution, or between the conductive part of the base material and the container containing the solution, or According to a preferred example in which a voltage is applied between the conductive part of the material and the electrode placed in the solution, the diamond particles can be uniformly and controllably reproducibly even with a large-area substrate material. It can be distributed. In addition, the distribution position of the particulate diamond can be selected.

In the method of the present invention, the amount of the particulate diamond dispersed in the solution to be used is 0.01 g or more and 100 g or less per liter of the solution, and more preferably 0.1 g or more and 20 g or less per liter of the solution. According to the preferred example, it is possible to easily distribute a sufficient number of diamond particles to the cold cathode portion of the substrate. The optimum amount of diamond particles at that time also depends on the average particle size of the particles used, and is approximately 1 g when the particle size is 0.01 μm and approximately 16 g when the particle size is 0.04 μm.

In the method of the present invention, the number of particulate diamonds dispersed in the solution to be used is 1 × 10 ¹⁶ to 1 × 10 ²⁰ per liter of the solution, and more preferably 1 × 10 ²⁰ or less per liter of the solution. × 10 ¹⁷ or more, 1 × 10
According to a preferred example having ¹⁹ or less, a sufficient number of diamond particles can be easily distributed to the cold cathode portion, similarly to the above configuration.

In the method of the present invention, according to a preferred example in which the solution on which the base material is placed contains water or alcohol as a main component, the solution is easy to handle and the solution is optimal as a dispersion solvent for diamond particles. is there.

According to a preferred embodiment of the method of the present invention, the solution in which the substrate is provided contains at least a compound containing fluorine (F) as a constituent element, such as hydrofluoric acid or ammonium fluoride. For example, it becomes easy to uniformly distribute diamond particles on a silicon substrate or the like.

In the structure of the method of the present invention, the distribution density of the particulate diamond disposed on the conductive layer or on the surface of the conductive layer is 1 × 10 ¹⁰ or more per square centimeter, more preferably 1 × 10 ¹⁰ per square centimeter.
According to a preferred example having 10 ¹¹ or more, it is possible to obtain a particulate diamond that can be a very large amount of electron emission source.

In the structure of the cold cathode device of the present invention, it is very important to control the surface of a structure that can serve as an electron emission source. The method of forming a surface structure suitable for using particulate diamond as an electron emission source is not particularly limited, but controls the conductivity of the diamond surface, that is, controls the elements bonded to carbon atoms on the diamond surface. It is easy to do. As a specific example,
By using a hydrogen-terminated surface (conductive), diamond can easily emit electrons, and by using an oxygen-terminated surface (insulating), it can be difficult to emit electrons. By arbitrarily controlling such surface state change, the device configuration and the manufacturing process of the high-efficiency electron-emitting device can be simplified.

Therefore, according to the structure of the method of the present invention, the method includes a step of irradiating a predetermined region of the particulate diamond arranged at the cold cathode portion with vacuum ultraviolet light having a wavelength of 200 nm or less. It is possible to selectively remove the element bonded to the diamond surface and form a new bond. As a result, it is possible to control the diamond surface state to be either positive (insulating) or negative (conductive).

Further, according to the configuration of the method of the present invention, a step of exposing a predetermined region of the particulate diamond arranged in the cold cathode portion to plasma obtained by subjecting at least hydrogen-containing gas to electric discharge decomposition is provided. Therefore, a hydrogen atom can be selectively bonded to the outermost carbon atom of diamond, and as a result, a region in which electrons can be easily emitted can be formed.

According to the structure of the method of the present invention, the method further comprises the step of exposing the particulate diamond disposed at the cold cathode portion to a gas containing at least hydrogen. A hydrogen atom can be bonded to an atom, and as a result, a region in a state where electrons can be easily emitted can be formed.

According to the structure of the method of the present invention, the method further comprises the step of exposing a predetermined region of the particulate diamond disposed at the cold cathode portion to plasma obtained by discharge-decomposing at least a gas containing oxygen. Therefore, an oxygen atom can be selectively bonded to the outermost carbon atom of diamond, and as a result, it is possible to form a region in which electron emission is difficult.

According to the structure of the method of the present invention, the method further comprises the step of exposing the particulate diamond arranged at the cold cathode portion to a gas containing at least oxygen. An oxygen atom can be bonded to an atom, and as a result, it is possible to form a region where electron emission is difficult.
By these manufacturing methods, an electron-emitting device that selectively emits electrons from an arbitrary portion can be formed.

As described above, by arbitrarily controlling the surface state of the diamond layer, the device configuration and manufacturing process of the high-efficiency electron-emitting device can be simplified.

Hereinafter, the present invention will be described more specifically with reference to examples. (First Embodiment) First, the results when micro-particulate diamond is used as an electron emission source arranged in the cold cathode portion will be described.

First, a base material is prepared. Although the material used for the substrate is not particularly limited, a conductive silicon substrate was used in this example.

Next, after the silicon substrate was cleaned in a usual cleaning step, the silicon substrate was placed in a cylindrical container made of quartz and subjected to thermal oxidation by heating in a wet oxygen atmosphere. Thermal oxidation conditions are 1000 ° C. for 2 hours. As a result, a silicon dioxide layer was formed in a region of about 1 μm in the surface layer of the silicon substrate.

Subsequently, after a photoresist material was applied thereon, a desired pattern was formed on the photoresist material by a usual photolithography process. The method for applying the photoresist material is not limited, but in this embodiment, a method in which a photoresist material is dropped on a rotated silicon substrate to form a coating, that is, spin coating is used. Although there is no particular limitation on the patterning shape, in this embodiment, a round dot having a diameter of 1 μm
Windows of 100 × 100, ie, 10,000, dots were formed at intervals of μm on the coated photoresist material.

Further, using the photoresist material as a mask, the silicon dioxide layer on the surface of the silicon substrate was removed by etching. The silicon dioxide layer was etched by wet etching using a hydrofluoric / nitric acid-based etchant. As a result, a round dot window having a diameter of 1 μm was formed in a portion where the silicon dioxide layer was removed.

Then, a solution in which diamond particles having an average particle size of 0.02 μm were dispersed was applied on a silicon substrate on which a patterned photoresist material and a silicon dioxide layer were laminated. In this embodiment, a solution obtained by dispersing 0.4 g of diamond particles in 1 liter of pure water and further adding 0.2 cc of hydrogen fluoride (concentration: 46%) is used. That is, a solution containing about 2 × 10 ¹⁷ diamond particles per liter of the solution was used as the number of diamond particles. The solution was applied by the same spin coating technique as that of applying the photoresist material. After the application, the silicon substrate was dried by irradiation with infrared lamp light.

Thereafter, the silicon substrate coated with the diamond particles is immersed in a solvent for removing resist for 10 minutes or more.
The photoresist material was removed. As a solvent for removing the resist, an organic solvent such as acetone can be generally used although it depends on the material of the photoresist material to be used.

Observation of the surface of the substrate obtained by the above method confirmed that fine diamond grains were distributed only in the portion where silicon was exposed (circle having a diameter of 1 μm). Its distribution density was about 5 × 10 ¹⁰ pieces / cm ² .

Further, an aluminum layer (Al) serving as a gate electrode was formed on the silicon dioxide layer serving as an insulator layer.

The electron-emitting device manufactured by the above method was placed in a vacuum of 10 ⁻⁶ Torr or less, and a positive voltage of about 30 V was applied to the gate electrode. It was confirmed that electrons were emitted from the diamond grains. That is, it was confirmed that the fine diamond grains acted as an electron emission source. Also, the emission current was larger than in the conventional case, and it was confirmed that electrons were emitted efficiently.

In this embodiment, when the type of the gate electrode is changed to another material, for example, molybdenum (Mo) or niobium (Nb), or when the solution is prepared by changing the particle size or amount of diamond particles to be applied. Similar results were obtained when an alcohol such as ethanol was used as a solvent, or when particles were changed to silicon carbide.

Further, the present inventors can control the trajectory of the emitted electron flow or focus it by installing a stop electrode on the gate electrode and applying a voltage to the stop electrode. Confirmed that there is.

(Second Embodiment) Similar to the first embodiment, fine diamond particles which can be an electron emission source are arranged on a patterned silicon substrate, and a diamond layer is further formed using the particles as nuclei. The result of the growth is described.

The base material used, the formation and patterning of the thermal oxide layer, the method of distributing diamond particles on silicon, and the like are the same as in the first embodiment.

In the present embodiment, before forming the gate electrode, a diamond layer was further formed on the diamond grains distributed on the substrate. The method for synthesizing the diamond layer is not particularly limited, but is often used because the vapor phase synthesis method is easy. The vapor phase synthesis method generally uses methane, ethane, ethylene, hydrocarbon gas such as acetylene, alcohol, an organic compound such as acetone, and a carbon source such as carbon monoxide diluted with hydrogen in a raw material gas, This is performed by decomposing the raw material gas. At that time, oxygen, water or the like can be added to the raw material gas as appropriate. Although there is no particular limitation on the applicable gas phase synthesis method, a diamond film was formed by a microwave plasma CVD method in this example. The microwave plasma CVD method is a method of forming a diamond by applying a microwave to a source gas to form diamond. As specific conditions, a carbon monoxide gas diluted to about 1 to 10 vol% with hydrogen was used as a source gas. Reaction temperature and pressure are 800 each
900900 ° C. and 25-40 Torr. A formation time of about 1 to 5 minutes is sufficient.

As a result of forming a diamond layer on diamond particles by the above-described method, the size of diamond particles arranged on silicon was about 0.2 to 0.5 μm. The surface state of the diamond particles was a state terminated by hydrogen.

Therefore, aluminum (Al) serving as a gate electrode was formed on the silicon dioxide layer serving as an insulator layer.

The electron-emitting device manufactured by the above method was placed in a vacuum of 10 ⁻⁶ Torr or less, and a positive voltage of about 30 V was applied to the gate electrode side. It was confirmed that electrons were emitted from the diamond grains. Also, the emission current was larger than in the conventional case, and it was confirmed that electrons were emitted efficiently. In addition, the surface of hydrogen-terminated diamond is extremely stable, so that the environment with a relatively poor vacuum (10 ^-4
(About Torr).

In this embodiment, when the type of the gate electrode is changed to another material, for example, molybdenum (Mo) or niobium (Nb), or when the solution is prepared by changing the diameter and amount of diamond particles to be applied. When alcohol such as ethanol is used as a dispersion solvent for fine diamond particles,
Further, similar results were obtained when a diamond layer was formed under other forming conditions.

Similar results were obtained when the surface of the obtained diamond particles was coated with a thin layer of cesium, nickel, titanium, tungsten or the like.

(Third Embodiment) Next, a description will be given of a result when ultrasonic vibration is used as a method of arranging fine diamond particles on a silicon substrate.

The base material used and the method of forming and patterning the thermal oxide layer are the same as those in the first embodiment. In this embodiment, a silicon substrate on which a patterned photoresist material and a silicon dioxide layer are stacked is placed in a container containing a solution in which diamond particles having an average particle size of about 0.02 μm are dispersed, and the entire container is placed. By applying ultrasonic vibration (hereinafter referred to as “ultrasonic vibration processing”), thereby distributing the fine diamond particles on the silicon region. In this embodiment, a solution is used in which 0.4 g of diamond particles are dispersed in 1 liter of pure water, and a 0.2 cc aqueous solution of ammonium fluoride (concentration: 40%) is further dropped. The power applied during the ultrasonic vibration processing is about 100 W, and the processing time is 5 to 15 minutes. The silicon substrate subjected to the ultrasonic vibration treatment was washed in pure water, and then dried by blowing with nitrogen gas.

When the surface of the exposed silicon portion of the silicon substrate subjected to the ultrasonic vibration treatment was observed with a scanning electron microscope, it was found that the fine diamond particles dispersed in the solution were uniformly distributed. The distribution density is ~
It was about 1 × 10 ¹¹ / cm ² .

Therefore, aluminum (Al) serving as a gate electrode was formed on the silicon dioxide layer.

The electron-emitting device manufactured by the above method was placed in a vacuum of 10 ⁻⁶ Torr or less, and a positive voltage of about 30 V was applied to the gate electrode. It was confirmed that electrons were emitted from the diamond grains. Also, the emission current was larger than in the conventional case, and it was confirmed that electrons were emitted efficiently.

In this embodiment, when the type of the gate electrode is changed to another material, for example, molybdenum (Mo) or niobium (Nb), or the particle size and amount of the diamond particles in the solution used for the ultrasonic vibration treatment are changed. Similar results were obtained when the solution was prepared by changing the solution, when the pH value of the solution was changed, or when the particles were changed to silicon carbide.

(Fourth Embodiment) Next, results obtained when the conditions of the ultrasonic vibration processing are changed are described.

The used base material, the substrate material cleaning step, and the solution used for the ultrasonic vibration treatment are the same as in the third embodiment. In the present embodiment, the ultrasonic vibration processing of the substrate material was performed under the conditions of an applied power of 350 W and a processing time of 30 minutes. When the surface of the silicon substrate subjected to the ultrasonic vibration treatment under these conditions was observed with a scanning electron microscope in the same manner as in the first embodiment, in addition to the fine diamond particles distributed on the exposed silicon, the surface of the silicon substrate was partially removed. Many fine diamond grains distributed in an embedded form were found. This is considered to be due to the fact that the applied power and the processing time under the ultrasonic vibration processing conditions of the present embodiment are larger than those of the third embodiment. The distribution density of the fine diamond grains distributed on the silicon and in the surface layer was further increased to reach about 5 × 10 ¹¹ / cm ² .

Therefore, aluminum (Al) serving as a gate electrode was formed on the silicon dioxide layer serving as an insulator layer.

The electron-emitting device manufactured by the above method was placed in a vacuum of 10 ⁻⁶ Torr or less, and a positive voltage was applied to the gate electrode side to about 30 V. As a result, the same result as in the third embodiment was obtained. Then, it was confirmed that electrons were emitted from the fine diamond grains arranged on the silicon substrate. Also, the emission current was larger than in the conventional case, and it was confirmed that electrons were emitted efficiently.

In the present embodiment, when the type of the gate electrode is changed to another material, for example, molybdenum (Mo) or niobium (Nb), or the particle size or amount of the diamond particles in the solution used for the ultrasonic vibration treatment is changed. Similar results were obtained when the solution was prepared by changing the solution, when the pH value of the solution was changed, or when the particles were changed to silicon carbide.

(Fifth Embodiment) Subsequently, as a method of arranging fine diamond particles on a silicon base material, after applying an ultrasonic vibration treatment, a diamond layer is further formed on the diamond particles before forming a gate electrode. The result in the case of forming was described.

The base material used, the formation and patterning of the thermal oxide layer, the method of distributing diamond particles on silicon, and the like are the same as in the fourth embodiment. The method for forming the diamond layer is the same as in the second embodiment.

As a result of forming a diamond layer on diamond grains by the above method, a large number of diamond grains having a size of about 0.2 to 0.5 μm were arranged on the exposed silicon. The surface state of the diamond particles was a state terminated by hydrogen.

Therefore, aluminum (Al) serving as a gate electrode was formed on the silicon dioxide layer serving as an insulator layer.

The electron-emitting device manufactured by the above method was placed in a vacuum of 10 ⁻⁶ Torr or less, and a positive voltage of about 30 V was applied to the gate electrode. It was confirmed that electrons were emitted from the diamond grains. Also, the emission current was larger than in the conventional case, and it was confirmed that electrons were emitted efficiently. In addition, the surface of hydrogen-terminated diamond is extremely stable, so that the environment with a relatively poor vacuum (10 ^-4
(About Torr).

In this embodiment, when the type of the gate electrode is changed to another material, for example, molybdenum (Mo) or niobium (Nb), or the particle size or amount of the diamond particles in the solution used for the ultrasonic vibration treatment is changed. Similar results were obtained when the solution was prepared in a different manner, or when the diamond layer was formed under other forming conditions.

(Sixth Embodiment) Next, a base material is placed in a solution in which fine diamond particles are dispersed, and a voltage is applied between a conductive part of the base material and an electrode to arbitrarily set the base material. The result of arranging fine diamond grains in the region will be described.

The used base material and the step of cleaning the base material are the same as in the above embodiment. Subsequently, the base material and a platinum plate electrode were placed in parallel in a container containing a solution containing diamond particles having an average particle size of about 0.02 μm, and the base material was placed between the silicon part and the platinum electrode. By applying a DC voltage (hereinafter referred to as “voltage application process”),
Fine diamond grains were distributed over the silicon area. In this embodiment, a solution in which 0.4 g of diamond particles is dispersed in 1 liter of pure water is used. The conditions of the voltage application process are as follows: the platinum electrode side is the negative electrode,
A voltage of 150 V was applied for 10 minutes. The substrate subjected to the voltage application treatment was washed with pure water, and then dried by blowing with nitrogen gas.

When the surface of the substrate subjected to the voltage application treatment was observed with a scanning electron microscope, it was found that fine diamond particles dispersed in the solution were uniformly distributed on the silicon to which the voltage was applied. Was. Further, the distribution density was about 3 × 10 ¹⁰ / cm ² . This is probably because the colloidal fine diamond particles in the solution had a negative charge and were attracted only to the silicon region used as the electrode by the voltage application treatment.

Therefore, aluminum (Al) serving as a gate electrode was formed on the silicon dioxide layer serving as an insulator layer.

The electron-emitting device manufactured by the above method was placed in a vacuum of 10 ⁻⁶ Torr or less, and a positive voltage of about 30 V was applied to the gate electrode. It was confirmed that more electrons were emitted. The emission current is also larger than before,
It was confirmed that electrons were efficiently emitted.

In this embodiment, when the type of the gate electrode is changed to another material, for example, molybdenum (Mo) or niobium (Nb), or the particle size or amount of the diamond particles in the solution used for the voltage application process is changed. The same results were obtained when the solution was prepared, when the pH value of the solution was changed, when a conductive container was used as the negative electrode without using a platinum electrode, and when the particles were changed to silicon carbide. was gotten.

(Seventh Embodiment) As a method for distributing fine diamond particles on a silicon substrate, after applying a voltage, a diamond layer is further formed on the diamond particles before forming a gate electrode. The results in the case of forming are described.

The used base material, the base material cleaning step, and the dispersion amount of the fine diamond particles in the solution used for the voltage application treatment are the same as those in the sixth embodiment. Also, the method of forming the diamond layer is the same as in the third embodiment.

As a result of forming a diamond layer on diamond particles by the above method, a large number of diamond particles having a size of about 0.2 to 0.5 μm were arranged on silicon. The surface state of the diamond particles was a state terminated by hydrogen.

Therefore, aluminum (Al) serving as a gate electrode was formed on the silicon dioxide layer serving as an insulator layer.

The electron-emitting device manufactured by the above method was placed in a vacuum of 10 ⁻⁶ Torr or less, and a positive voltage of about 30 V was applied to the gate electrode. It was confirmed that electrons were emitted from the diamond grains. Also, the emission current was larger than in the conventional case, and it was confirmed that electrons were emitted efficiently. In addition, the surface of hydrogen-terminated diamond is extremely stable, so that the environment with a relatively poor vacuum (10 ^-4
(About Torr).

In this embodiment, when the type of the gate electrode is changed to another material, for example, molybdenum (Mo) or niobium (Nb), or the particle size or amount of the diamond particles in the solution used for the voltage application process is changed. Similar results were obtained when the solution was prepared by using the above method, and when the diamond layer was formed under other forming conditions.

(Eighth Embodiment) Next, as a procedure of a cold cathode element forming process, a result in a case where fine diamond grains are arranged in the cold cathode portion after forming up to the gate electrode will be described.

First, the conductive silicon substrate was cleaned by a normal cleaning process, and then thermally oxidized to form a silicon dioxide layer on the silicon surface. Further, aluminum (Al) serving as a gate electrode is formed on a silicon dioxide layer serving as an insulator layer.
Was formed.

Subsequently, after a photoresist material is applied thereon, a desired pattern is formed on the photoresist material by a usual photolithography process, and the gate electrode and the silicon dioxide layer are formed using the photoresist material as a mask. Was removed by etching. Thereafter, micro diamond particles were distributed by ultrasonic vibration treatment on the exposed silicon portion of the silicon substrate on which the patterned photoresist material, gate electrode, and silicon dioxide layer were laminated. The conditions of the ultrasonic vibration processing are the same as in the third embodiment.

The electron-emitting device manufactured by the above method was placed in a vacuum of 10 ⁻⁶ Torr or less, and a positive voltage of about 30 V was applied to the gate electrode. It was confirmed that electrons were emitted from the diamond grains. Also, the emission current was larger than in the conventional case, and it was confirmed that electrons were emitted efficiently.

In the present embodiment, when the type of the gate electrode is changed to another material, for example, molybdenum (Mo) or niobium (Nb), or the particle size or amount of the diamond particles in the solution used for the ultrasonic vibration treatment is changed. Similar results were obtained when the solution was prepared in a different manner.

(Ninth Embodiment) Next, as a device size of the cold cathode device, a result when the distance between the conductive layer and the gate electrode is changed will be described.

First, the conductive silicon substrate was cleaned in a usual cleaning step, and then thermally oxidized to form a silicon dioxide layer on the silicon surface. In this embodiment, the thickness of the silicon dioxide layer used as the insulator layer is 0.3 μm. Further, aluminum (Al) serving as a gate electrode was formed on the silicon dioxide layer serving as an insulator layer.

With this structure, the distance between the conductive layer and the gate electrode can be reduced to 0.5 μm or less.

Subsequently, as in the above-described embodiment, fine diamond grains were distributed by ultrasonic vibration treatment on exposed portions of the silicon through the steps of applying and patterning a photoresist material, etching the gate electrode and the silicon dioxide layer. The conditions for the ultrasonic vibration treatment are the same as in the third embodiment, except that the average particle size of the fine diamond particles used is 0.01 μm.

The electron-emitting device manufactured by the above method was placed in a vacuum of 10 ⁻⁶ Torr or less, and a positive voltage was applied to the gate electrode side to about 30 V. As a result, the emission current amount further increased. It was confirmed that electrons were efficiently emitted. That is, the cold cathode device can be driven at a lower voltage.

In the present embodiment, similar results were obtained when minute diamond particles were distributed by another method.

(Tenth Embodiment) Next, as the element size of the cold cathode element, a result when the area of the opening of the cold cathode part is changed will be described.

First, the conductive silicon substrate was cleaned in a usual cleaning step, and then thermally oxidized to form a silicon dioxide layer on the silicon surface. Also in the present embodiment, the thickness of the silicon dioxide layer used as the insulator layer is 0.3 μm. Further, aluminum (Al) serving as a gate electrode was formed on the silicon dioxide layer serving as an insulator layer.

Subsequently, a photoresist material was applied and patterned in the same manner as in the above embodiment. In the present embodiment, the size of the window opened in the photoresist material is 0.4 μm in diameter. Thereafter, the gate electrode and the silicon dioxide layer were etched. As a result, a structure was obtained in which the area of the opening of the cold cathode portion was 2 × 10 ⁻⁹ cm ² or less. The obtained base material was subjected to a voltage application treatment to distribute fine diamond grains. The conditions for the voltage application process are the same as in the sixth embodiment, except that the average particle size of the fine diamond particles used is 0.01 μm.

The electron-emitting device manufactured by the above method was placed in a vacuum of 10 ⁻⁶ Torr or less, and a positive voltage of about 30 V was applied to the gate electrode side. It was confirmed that electrons were emitted more efficiently than diamond grains. That is, it has become possible to form a cold cathode element with a smaller area.

In the present embodiment, similar results were obtained even when minute diamond particles were distributed by another method.

(Eleventh Embodiment) This embodiment describes a case where glass is used as a base material.

First, the glass as a base material was cleaned in a usual washing step, and then a conductive layer serving as a lower electrode was formed in a linear shape. The material of the conductive layer is not particularly limited, and may be a normal metal layer or a low-resistance layer only, or may be a laminated structure of a resistor layer, a metal layer, and a low-resistance layer. In this embodiment, an aluminum layer was used.

Subsequently, after a silicon dioxide layer serving as an insulator layer was formed on the entire surface of the base material by a method such as sputtering or a CVD method, the photoresist material was patterned. Also in the present embodiment, the patterning shape is not particularly limited, but is 1 μm in diameter in the present embodiment.
100 × 100 round dots of 20 μm intervals, that is, 1000
A window of zero dots was formed in the photoresist material on the aluminum layer.

Further, using the photoresist material as a mask, the silicon dioxide layer was removed by etching. As a result, a portion having a diameter of 1 μm
A round dot window was formed.

Next, this base material and a flat plate electrode made of platinum were placed parallel to each other in a container containing a solution in which diamond particles having an average particle size of about 0.02 μm were dispersed, and formed on the base material. A voltage application process for applying a DC voltage between the aluminum layer and the platinum electrode was performed. The conditions of the voltage application processing used in this embodiment are the same as those in the sixth embodiment. The substrate subjected to the voltage application treatment was washed with pure water, and then dried by blowing with nitrogen gas.

When the surface of the substrate subjected to the voltage application treatment was observed with a scanning electron microscope, the fine diamond particles dispersed in the solution were uniformly distributed only in the circular window portion of the aluminum layer to which the voltage was applied. It turned out that it was distributed. Further, the distribution density was about 3 × 10 ¹⁰ / cm ² . Therefore, aluminum (Al) serving as a gate electrode was further formed on the silicon dioxide layer.

The electron-emitting device manufactured by the above method was placed in a vacuum of 10 ⁻⁶ Torr or less, and a positive voltage of about 30 V was applied to the gate electrode side. It was confirmed that electrons were emitted from the diamond grains. Also, the emission current was larger than in the conventional case, and it was confirmed that electrons were emitted efficiently.

In this embodiment, when the type of the gate electrode or the conductive layer is changed to another material or a laminated structure, or when the solution is prepared by changing the particle size or amount of the diamond particles in the solution used for the voltage application process. Similar results were obtained when the pH value of the solution was changed, when a conductive container was used as the negative electrode without using a platinum electrode, and when the particles were changed to silicon carbide.

Similar results can be obtained when the voltage application process is performed after the gate electrode is formed before the voltage application process, or when diamond grains are arranged by another method, such as an ultrasonic vibration process. Was.

(Twelfth Embodiment) In the present embodiment, a case where a linear cold cathode portion is formed on a linear lower electrode layer using glass as a base material will be described.

As in the eleventh embodiment, first, the glass as the base material was cleaned by a normal cleaning step, and then a conductive layer (material: Al) serving as a lower electrode was formed in a linear shape. Subsequently, after a silicon dioxide layer serving as an insulator layer and a gate electrode layer were formed on the entire surface of the base material, patterning of a photoresist material was performed. In this embodiment mode, a linear window having a width of 1 μm is formed on the coated photoresist material, and the gate electrode layer and the silicon dioxide layer are removed by etching using the photoresist material as a mask. As a result, the width is 1μ
A linear window of m was formed.

Next, this substrate and a platinum plate electrode were placed parallel to each other in a container containing a solution in which diamond particles having an average particle size of about 0.02 μm were dispersed. And a platinum electrode to apply a DC voltage.

The electron-emitting device manufactured by the above method was placed in a vacuum of 10 ⁻⁶ Torr or less, and a positive voltage of about 30 V was applied to the gate electrode. It was confirmed that electrons were emitted linearly from the diamond grains.

In this embodiment, when the type of the gate electrode or the conductive layer is changed to another material or a laminated structure, or when the solution is prepared by changing the diameter or amount of diamond particles in the solution used for the voltage application process. Similar results were obtained when the pH value of the solution was changed, when a conductive container was used as the negative electrode without using a platinum electrode, and when the particles were changed to silicon carbide.

Similar results can be obtained when the voltage application process is performed after the gate electrode is formed before the voltage application process, or when diamond grains are arranged by another method, such as an ultrasonic vibration process. Was.

(Thirteenth Embodiment) As a method of controlling the surface structure of diamond grains as an electron emission source, a result of irradiating a predetermined region of diamond grains with vacuum ultraviolet light having a wavelength of 200 nm or less will be described.

First, the surface condition of the diamond particles placed on the conductive layer heated in an oxygen atmosphere was examined, and it was found that the diamond particles had a surface terminated with oxygen. As a result of evaluating the electron emission characteristics of the cold cathode device composed of such diamond grains, the applied voltage was higher than that in the case where hydrogen was terminated. Accordingly, diamond particles having an oxygen-terminated surface were irradiated with vacuum ultraviolet light having a wavelength of 200 nm or less in a vacuum atmosphere of about 10 ⁻⁷ Torr or a hydrogen atmosphere. The irradiation amount of the vacuum ultraviolet light at this time is not particularly limited because it depends on the irradiation rate and the like, but in this embodiment, 10 ¹¹ photons are irradiated for 15 minutes per second. As a result, it was confirmed that the bond between carbon and oxygen on the outermost surface of the region irradiated with the vacuum ultraviolet light was broken and changed to a bond with hydrogen, and that the electron emission characteristics of the cold cathode device were also improved. all right. That is, it was confirmed that by using this process, it was possible to control the surface state of diamond grains serving as electron emission sources.

(Fourteenth Embodiment) As a method of controlling the surface structure of diamond grains as an electron emission source, a result of exposing a predetermined region of diamond grains to plasma obtained by discharge decomposition of hydrogen gas will be described.

First, diamond grains whose surface was terminated with oxygen were prepared. The characteristics of the cold cathode device having the diamond grains are deteriorated as described above. Then, the region of the oxygen-terminated diamond particles was exposed to ECR discharge plasma of hydrogen gas. The hydrogen plasma irradiation time at that time was 20
Seconds. As a result, it was confirmed that the outermost surface carbon in the region exposed to the hydrogen plasma was changed into a bond with hydrogen, and it was found that the electron emission characteristics of the cold cathode device were also improved. That is, it was confirmed that by using this process, it was possible to control the surface state of diamond grains serving as electron emission sources.

The same applies to the case where the time for exposing the hydrogen gas to the ECR discharge plasma is changed, the case where the hydrogen gas is diluted to about 10% with argon or nitrogen, and the case where the hydrogen gas is exposed to the hydrogen plasma formed by another method. Was obtained.

(Fifteenth Embodiment) As a method of controlling the surface structure of diamond particles as an electron emission source, a result of exposing diamond particles to hydrogen gas under heating will be described.

First, diamond grains whose surface was terminated with oxygen were prepared. The characteristics of the cold cathode device having the diamond grains are deteriorated as described above. Therefore, a cold cathode device having oxygen-terminated diamond particles was set in a cylindrical container in which hydrogen gas was flown, and heated to 600 ° C. The processing time at that time is 10 minutes. As a result, it was confirmed that the outermost surface carbon of the diamond particles heated in the hydrogen atmosphere was changed into a bond with hydrogen, and that the electron emission characteristics of the cold cathode device were also improved. That is, it was confirmed that by using this process, it was possible to control the surface state of diamond grains serving as electron emission sources.

Similar results were obtained when the hydrogen gas flowing through the container was diluted to about 10% with argon or nitrogen, or when the heating temperature was changed in the range of 400 to 900 ° C.

(Sixteenth Embodiment) As a method of controlling the surface structure of diamond grains as an electron emission source, a result of exposing a predetermined region of diamond grains to plasma obtained by discharge decomposition of oxygen gas will be described.

First, diamond grains whose surface was terminated with hydrogen were prepared. In order to limit the electron emission region of the cold cathode device composed of such diamond grains, a part of the cold cathode portion where the diamond grains were arranged was exposed to ECR discharge plasma of oxygen gas. The oxygen plasma irradiation time at that time is 20 seconds. As a result, it was confirmed that the outermost surface carbon in the region exposed to the oxygen plasma was changed into a bond with oxygen, and it was found that the region where electrons were emitted could be controlled. That is, it was confirmed that by using this process, it was possible to control the surface state of diamond grains serving as electron emission sources.

The same applies when the time of exposing oxygen gas to ECR discharge plasma is changed, when oxygen gas is diluted to about 10% with argon or nitrogen, or when it is exposed to oxygen plasma formed by another method. Was obtained.

(Seventeenth Embodiment) As a method of controlling the surface structure of diamond grains as an electron emission source, a result of exposing diamond grains to oxygen gas under heating will be described.

First, diamond grains whose surface was terminated with hydrogen were prepared. In order to limit the electron emission region of the cold cathode device composed of such diamond grains, a partial region was exposed to oxygen gas. As a result, it was confirmed that the outermost surface carbon of the diamond particles exposed to the oxygen atmosphere was changed into a bond with oxygen, and it was found that the region where electrons were emitted could be controlled. That is, it was confirmed that by using this process, it was possible to control the surface state of diamond grains serving as electron emission sources.

Similar results were obtained when the oxygen gas exposed to the diamond particles was diluted to about 10% with argon or nitrogen, or when the heating temperature was changed.

[0178]

As described above, according to the cold cathode device according to the present invention, the conductive layer, the cold cathode portion formed on the conductive layer, and the gate electrode for extracting electrons from the cold cathode portion are provided. Since the cold cathode element has a structure that includes a structure that can serve as a plurality of electron emission sources, electrons are emitted from a large number of electron emission sources. A large electron emission current can be obtained, and electron emission with good stability as a whole can be obtained.

According to the cold cathode device of the present invention, the cold cathode includes a conductive layer, a cold cathode portion formed on the conductive layer, and a gate electrode for extracting electrons from the cold cathode portion. The device has a configuration including a cold cathode portion including a structure that can serve as a plurality of electron emission sources, and an aperture electrode for controlling the trajectory of the extracted electrons. The orbit and the beam diameter can be controlled.

According to the structure of the present invention, the structure in which the distance between the conductive layer and the gate electrode is 0.5 μm or less, or the structure in which the area of the opening of the cold cathode portion is 2 × 10 ⁻⁹ cm ² or less. Because it is characterized by including, it is possible to manufacture a cold cathode device having characteristics equal to or greater than a conventional device at a smaller distance and area, so that it is possible to produce a small cold cathode device with higher integration at a lower voltage. It becomes possible.

According to the method of the present invention, the average particle size is
Since the step of distributing 0.2 μm or less of particulate diamond on the conductive layer, or the step of embedding the particulate diamond having an average particle size of 0.2 μm or less in the conductive layer is characterized in that it is used as a cold cathode material, Since highly suitable diamond can be arranged with good reproducibility on the conductive layer or on the surface of the conductive layer in the form of fine particles or agglomerates thereof that can be an electron emission source, it is possible to easily form a highly efficient cold cathode device. It becomes possible. Further, a similar effect can be obtained by a structure in which a diamond layer is grown using diamond particles arranged on the conductive layer or on the surface of the conductive layer as nuclei.

According to the structure of the method of the present invention, the method further comprises the step of irradiating a predetermined region of the particulate diamond arranged in the cold cathode portion with vacuum ultraviolet light having a wavelength of 200 nm or less. Since it becomes possible to selectively remove elements bonded to the diamond surface and form new bonds, it is possible to control the diamond surface state to either positive (insulating) or negative (conductive). Become.

According to the structure of the method of the present invention, the method further comprises the step of exposing a predetermined region of the particulate diamond disposed at the cold cathode portion to plasma obtained by subjecting at least a gas containing hydrogen to electric discharge decomposition, or Since it has a step of exposing the particulate diamond arranged at the cold cathode portion to a gas containing at least hydrogen, it is possible to selectively bond hydrogen atoms to the outermost carbon atoms of diamond, and as a result, It is possible to form a region in a state where electrons are easily emitted.

According to the configuration of the method of the present invention, the method further comprises the step of exposing a predetermined region of the particulate diamond disposed at the cold cathode portion to plasma obtained by discharge-decomposing at least a gas containing oxygen. Since it has a step of exposing the particulate diamond arranged in the cold cathode portion to a gas containing at least oxygen, it is possible to selectively bind oxygen atoms to the outermost carbon atoms of diamond, and as a result, This makes it possible to form a region where electron emission is difficult. By these manufacturing methods, an electron-emitting device that selectively emits electrons from an arbitrary portion can be formed. By arbitrarily controlling the surface state of the diamond layer as described above, the device configuration and the manufacturing process of the high-efficiency electron-emitting device can be simplified.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a basic structure of a cold cathode device according to the present invention.

FIG. 2 is a cross-sectional view showing a basic structure of a conventional cold cathode device as a comparative example.

FIG. 3 is a sectional view showing a basic structure of another cold cathode device according to the present invention.

FIG. 4 is a photograph showing a shape of a surface of a cold cathode device according to the present invention observed with a microscope.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base material 2 Conductive layer 3 Cold cathode part 4 Insulator layer 5 Gate electrode 6 Structure which can be an electron emission source 7 Aperture electrode

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tetsuya Shiratori 1006 Kazuma Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (36)

[Claims] 1. A cold cathode device comprising: a conductive layer; a cold cathode portion formed on the conductive layer; and a gate electrode for extracting electrons from the cold cathode portion, wherein the cold cathode portion includes A cold cathode device, wherein a portion that can be an electron emission source is divided into a plurality of portions. 2. A cold cathode device comprising: a conductive layer; a cold cathode portion formed on the conductive layer; and a gate electrode for extracting electrons from the cold cathode portion, wherein a plurality of electron emitting devices are provided. A cold-cathode device comprising a cold-cathode portion including a structure that can serve as a source, and an aperture electrode for controlling the trajectory of the extracted electrons. 3. The cold-cathode device according to claim 1, wherein a structure that can be a plurality of electron-emitting sources arranged in the cold-cathode portion is embedded in the surface layer of the conductive layer. 4. The cold-cathode device according to claim 1, wherein a plurality of electron emission sources arranged in the cold-cathode portion are isolated. 5. The cold cathode device according to claim 1, wherein the structure that can be a plurality of electron emission sources disposed in the cold cathode portion is in the form of particles or aggregates of particles. 6. The cold cathode device according to claim 5, wherein the average diameter of the particles arranged in the cold cathode portion is 0.2 μm or less. 7. The cold-cathode device according to claim 5, wherein the distribution density of the particles or aggregates of the particles arranged in the cold-cathode portion is at least 1 × 10 ¹⁰ per square centimeter. 8. The cold-cathode device according to claim 1, wherein the structure that can be a plurality of electron-emitting sources disposed in the cold-cathode portion is made of diamond. 9. The surface of a diamond disposed on a cold cathode portion is made of cesium (Cs), nickel (Ni), titanium (T
9. The cold cathode device according to claim 8, comprising a configuration coated with any one of i), tungsten (W), hydrogen (H), and amorphous carbon. 10. The cold cathode according to claim 9, wherein a substance covering the surface of the diamond disposed on the cold cathode portion has an attached atom density of 1 × 10 ¹⁷ or less per square centimeter. Cathode element. 11. The cold cathode device according to claim 8, wherein a carbon atom on the outermost surface of the diamond disposed in the cold cathode portion has a structure terminated by a bond with a hydrogen atom. 12. The method according to claim 11, wherein the amount of hydrogen atoms bonded to carbon atoms on the outermost surface of the diamond disposed on the cold cathode portion is 1 × 10 ¹⁵ or more per square centimeter. Cold cathode device. 13. The cold cathode device according to claim 1, wherein the conductive layer has a multilayer structure including at least one semiconductor layer. 14. A cold cathode device comprising: a conductive layer; a cold cathode portion formed on the conductive layer; and a gate electrode for extracting electrons from the cold cathode portion, wherein the cold cathode element includes A cold cathode device comprising a configuration in which a distance between gate electrodes is 0.5 μm or less. 15. A cold cathode device comprising: a conductive layer; a cold cathode portion formed on the conductive layer; and a gate electrode for extracting electrons from the cold cathode portion, wherein the cold cathode portion includes A cold cathode device comprising a configuration in which the area of the opening is 2 × 10 ⁻⁹ cm ² or less. 16. A method for manufacturing a cold cathode device comprising: a conductive layer; a cold cathode portion formed on the conductive layer; and a gate electrode for extracting electrons from the cold cathode portion, the method comprising: A method for manufacturing a cold cathode device, comprising a step of distributing particulate diamond having a diameter of 0.2 μm or less on the conductive layer. 17. A method for manufacturing a cold cathode device comprising a conductive layer, a cold cathode portion formed on the conductive layer, and a gate electrode for extracting electrons from the cold cathode portion, the method comprising: A method for manufacturing a cold cathode device, comprising: distributing particulate diamond having a diameter of 0.2 μm or less on the conductive layer; and growing a diamond layer on the particulate diamond. 18. A method for manufacturing a cold cathode device comprising a conductive layer, a cold cathode portion formed on the conductive layer, and a gate electrode for extracting electrons from the cold cathode portion, the method comprising: A method for manufacturing a cold cathode device, comprising a step of embedding particulate diamond having a diameter of 0.2 μm or less in the conductive layer. 19. A method for manufacturing a cold cathode device, comprising: a conductive layer; a cold cathode portion formed on the conductive layer; and a gate electrode for extracting electrons from the cold cathode portion, the method comprising: A method of manufacturing a cold cathode device, comprising: a step of embedding particulate diamond having a diameter of 0.2 μm or less in the conductive layer; and a step of growing a diamond layer on the particulate diamond. 20. The method according to claim 17, wherein the step of growing a diamond layer on the particulate diamond is a vapor phase synthesis method. 21. The method according to claim 16, wherein the step of disposing the particulate diamond on the conductive layer or on the surface of the conductive layer is after the step of forming the insulator layer in a partial region on the base material. , 17, 18, and 19. 22. The method according to claim 16, wherein the step of disposing the particulate diamond on the conductive layer or on the surface of the conductive layer is performed after the step of forming the gate electrode.
20. The method for manufacturing a cold cathode device according to any one of 18 and 19. 23. A method for arranging particulate diamond on a conductive layer or on a surface of a conductive layer, wherein a solution in which particulate diamond having an average particle diameter of 0.2 μm or less is dispersed is applied to a substrate. Item 20. The method for producing a cold cathode device according to any one of Items 16, 17, 18, and 19. 24. A method for arranging particulate diamond on a conductive layer or on a surface of a conductive layer is such that a base material is placed in a solution in which particulate diamond having an average particle size of 0.2 μm or less is dispersed, and 20. The method of manufacturing a cold cathode device according to claim 16, wherein ultrasonic vibration is applied. 25. A method for arranging particulate diamond on a conductive layer or a surface layer of a conductive layer, comprising: disposing a substrate in a solution in which particulate diamond having an average particle size of 0.2 μm or less is dispersed; 18. A voltage is applied between the conductive part of the substrate and the container containing the solution, or between the conductive part of the base material and the electrode provided in the solution.
20. The method for manufacturing a cold cathode device according to any one of 18 and 19. 26. The amount of particulate diamond dispersed in a solution in which a substrate is placed is 0.01 to 1 liter of the solution.
25 g or more and 100 g or less.
26. The method for manufacturing a cold cathode device according to 24 or 25. 27. The number of particulate diamonds dispersed in a solution in which a substrate is placed is 1 × / liter of solution.
26. The method according to claim 23, 24 or 25, wherein the number is 10 ¹⁶ or more and 1 × 10 ²⁰ or less. 28. The solution according to claim 23, wherein the solution in which the base material is placed contains water or alcohol as a main component.
26. The method for manufacturing a cold cathode device according to 4 or 25. 29. The method for manufacturing a cold cathode device according to claim 23, wherein the solution in which the substrate is provided contains at least a compound containing fluorine (F) as a constituent element. 30. The method according to claim 29, wherein the compound containing fluorine as a constituent element is hydrofluoric acid or ammonium fluoride. 31. The method according to claim 23, 24 or 25, wherein the distribution density of the particulate diamond arranged on the conductive layer or on the surface of the conductive layer is 1 × 10 ¹⁰ or more per square centimeter. A method for manufacturing a cold cathode device. 32. A method for manufacturing a cold cathode device comprising: a conductive layer; a cold cathode portion formed on the conductive layer; and a gate electrode for extracting electrons from the cold cathode portion, the method comprising: A method for manufacturing a cold cathode device, comprising a step of irradiating a predetermined region of particulate diamond arranged in a portion with vacuum ultraviolet light having a wavelength of 200 nm or less. 33. A method of manufacturing a cold cathode device comprising: a conductive layer; a cold cathode portion formed on the conductive layer; and a gate electrode for extracting electrons from the cold cathode portion, the cold cathode device comprising: A method for manufacturing a cold cathode device, comprising a step of exposing a predetermined region of particulate diamond disposed in a portion to a plasma obtained by subjecting a gas containing at least hydrogen to discharge decomposition. 34. A method for manufacturing a cold cathode device, comprising: a conductive layer; a cold cathode portion formed on the conductive layer; and a gate electrode for extracting electrons from the cold cathode portion, the cold cathode device comprising: A method for manufacturing a cold cathode device, comprising a step of exposing a predetermined region of the particulate diamond arranged in a portion to a gas containing at least hydrogen. 35. A method for manufacturing a cold cathode device comprising: a conductive layer; a cold cathode portion formed on the conductive layer; and a gate electrode for extracting electrons from the cold cathode portion, the method comprising: A method for manufacturing a cold cathode device, comprising a step of exposing a predetermined region of particulate diamond disposed in a portion to a plasma obtained by discharge-decomposing a gas containing at least oxygen. 36. A method of manufacturing a cold cathode device comprising: a conductive layer; a cold cathode portion formed on the conductive layer; and a gate electrode for extracting electrons from the cold cathode portion, the method comprising: A method for manufacturing a cold cathode device, comprising a step of exposing a predetermined region of particulate diamond disposed in a portion to a gas containing at least oxygen.