JPH11135002A - Electron emission element and its manufacture and electron emission source and phosphor luminescence device using the element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an efficient and highly stable electron emission element by arranging a film to be an electron emission portion on a conductive layer or between the conductive layers. SOLUTION: By arranging plural electrode portions 2, 3, an electrode portions 2,3-arranged conduction layer 4, and a film 5 on a conductive layers or between conductive layers, electrons are effectively emitted, and highly stable electron emission can be obtained. In a formation process of a diamond film or a film 5 mainly composed of diamond to be an electron emission portion, by providing a process distributing grain diamond of 0.2 μ or less in average grain size, and a process causing the diamond to additionally grow into the grain diamond, the diamond film very suitable for electron emission material is arranged on the conductive layer or between conductive layers with excellent reproducibility so that a highly efficient electron emission element can be easily formed.

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 for emitting an electron beam, and more particularly to an electron-emitting device having an electron-emitting portion formed of a diamond film or a film containing diamond as a main component, and a method of manufacturing the same. The present invention also provides
The present invention relates to a highly efficient and stable electron emission source and a phosphor light emitting device.

[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. Known types of such electron-emitting devices include a field emission type (FE type), a tunnel injection type (MIM type, MIS type), and a surface conduction type (SC type).

The FE type electron-emitting device emits electrons from a cone-shaped protrusion made of silicon (Si) or molybdenum (Mo) by applying a voltage to a gate electrode and applying an electric field to the electron-emitting portion. It is to let.

[0004] Further, the MIM-type and MIS-type elements form a laminated structure of a metal, an insulator layer, a semiconductor layer, and the like, so that a part of electrons injected from the metal side is extracted to the outside from an electron emitting portion. is there.

[0005] In the SC type, electrons are extracted from an electron emission portion formed in advance by flowing a current in an in-plane direction of a thin film formed on a substrate. Electrons are emitted from the fine cracks.

[0006] These element structures have features such as downsizing and integration by using fine processing technology.

[0007]

Generally, the characteristics required for an electron-emitting device include that an electron can be efficiently emitted and that the obtained electron emission current has good stability. Another reason is that the change over time in the electron emission characteristics is small. For this purpose, it is necessary to properly select the structure and material of the electron-emitting portion in addition to the configuration of the electron-emitting device to be used. However, there has been a problem that the characteristics of the electron-emitting device obtained hitherto are such that the shape-dependence of the electron-emitting portion and a change with time are large. In addition, there is a problem that control is very difficult from the viewpoint of manufacturing an element with good reproducibility.

As described above, the structure of the electron-emitting device itself, the structure of the electron-emitting portion, and the material used so far do not sufficiently satisfy the required characteristics.

The present invention solves the above-mentioned problems in the prior art by disposing a film serving as an electron emitting portion on a conductive layer to which a current is applied or between conductive layers.
An object is to provide an electron-emitting device that efficiently emits electrons and has high stability.

Another object of the present invention is to provide a highly efficient electron emission source and a phosphor light emitting device by using an electron emission source having a plurality of the electron emission elements.

Further, the method of the present invention includes a step of forming a diamond film or a film containing diamond as a main component, which is to be an electron-emitting portion by a vapor phase synthesis method, so that an electron-emitting device having a stable electron-emitting portion can be easily manufactured. It is an object of the present invention to provide a method that can be manufactured with high reproducibility.

Another object of the present invention is to provide a method for easily and rationally performing an important manufacturing process for a diamond film or a film containing diamond as a main component, which is used as an electron-emitting portion in an electron-emitting device. I do.

[0013]

In order to achieve the above object, at least the structure of the electron-emitting device according to the present invention is as follows.
A plurality of electrode portions, a conductive layer on which the electrode portions are disposed, and a film serving as an electron emitting portion are disposed on the conductive layer.

In order to achieve the above object, an electron-emitting device according to the present invention comprises at least a plurality of electrode portions, a plurality of conductive layers on which the electrode portions are arranged, and an electron-emitting portion between the conductive layers. Characterized in that a film to be formed is disposed.

Further, in the present invention, in the above-mentioned element structure, it is preferable that a film thickness is 1 μm or less. More preferably, it is 500 nm or less.

In the present invention, it is preferable that in the device, a current is applied in an in-plane direction of the conductive layer. The amount of current to be applied is not particularly limited because it depends on the thickness and size of the conductive layer, the electric resistance value, and the like, but generally 1 to 100 mA is preferable.

In the present invention, it is preferable that the conductive layer is heated while applying a current in an in-plane direction of the conductive layer. Also in this case, the amount of applied current is the same as described above. Further, the heating temperature varies depending on the material used for the conductive layer and the like, and thus cannot be specified unconditionally. However, approximately 300 to 600 ° C. is practical. For this heating, a mechanism for heating the conductive layer from the outside may be provided,
The conductive layer may be heated by Joule heat generated by energizing the conductive layer itself.

Further, according to the present invention, in the above-mentioned element, by controlling the amount of current flowing in the in-plane direction of the conductive layer,
It is preferable to modulate the amount of emitted electrons taken out.

FIG. 1 is an example of a schematic plan view (a) and a sectional view (b) showing the basic structure of an electron-emitting device according to the present invention. As shown in FIG. 1, the present electron-emitting device includes, as main components, a substrate 1, electrodes 2 and 3, a conductive layer 4, and a film 5 serving as an electron-emitting portion laminated on the conductive layer. Consists of

FIG. 2 shows a film 5 serving as an electron emitting portion in FIG.
FIG. 4 is an enlarged view of the vicinity, schematically illustrating the concept of electron emission from an electron-emitting device according to the present invention. The details will be described below. First, when a predetermined voltage is applied between the electrode portions 2 and 3 of the electron-emitting device, a constant current flows through the conductive layer 4. FIG. 2 shows a state in which electrons 6 are conducted in the conductive layer 4 by applying a voltage. At this time, by disposing a layer having a relatively low electric resistance value and easily emitting electrons, that is, a film 5 serving as an electron emitting portion, on the conductive layer 4, some of the electrons conducted through the conductive layer 4 become electrons. The light is transmitted to the inside and the surface layer of the film 5 serving as the emission portion. Further, the electrons 6 transmitted to the film 5 serving as an electron emitting portion are extracted to the outside by an appropriate electric field, and become emitted electrons 7. That is, by arranging the film 5 serving as an electron emitting portion on the conductive layer 4, it is possible to uniformly extract the current flowing through the conductive layer 4 to the outside. Although not shown, the substrate 1
By arranging another electrode for controlling the emitted electron flow at a position opposite to the above, acceleration of the emitted electrons 7 and control of the orbit can be performed.

Normally, the emitted electrons 7 can be obtained only by applying a current to the conductive layer 4 as described above.
By heating, more efficient electron emission is realized with the aid of thermal energy.

The amount of emitted electrons can be controlled by changing the amount of an electric field applied to the film 5 serving as an electron-emitting portion, but can also be controlled by changing the amount of current flowing through the conductive layer 4. It is. In FIG. 1, the conductive layer 4
The electrode portions 2 and 3 are disposed so as to cover the electrode portion 2. However, the present invention is not limited to this. good. When the material of the conductive layer 4 is a metal, the electrode portion may be formed of the conductive layer itself. In addition, in order to increase the transmission efficiency of electrons flowing through the conductive layer, the thickness of the conductive layer 4 may be reduced only in the portion where the film 5 serving as an electron emission portion is disposed.

In the above description, a pair of conductive layers 4 and a film 5 serving as an electron emitting portion are arranged for a pair of electrode portions 2 and 3, but the schematic plan view (a) shown in FIG. Thus, a plurality of pairs of conductive layers 4 and electron emission portions 5 are provided for one set of electrode portions 2 and 3.
May be arranged in parallel. Further, as shown in the schematic plan view of FIG. 3 (b), a plurality of conductive layers 4 formed in parallel with one set of electrodes 2 and 3, and a film serving as an electron emitting portion so as to cover the plurality of conductive layers 4 5 may be arranged.

FIG. 4 is a schematic plan view (a) and a sectional view (b) showing the basic structure of another electron-emitting device according to the present invention.
This is an example. As in FIG. 1, the present electron-emitting device includes a base material 1, electrode portions 2 and 3, and a conductive layer 4 as main components.
a, 4b, and a film 5 serving as an electron emission portion laminated between conductive layers.

FIG. 5 shows a film 5 serving as an electron emitting portion in FIG.
FIG. 4 is an enlarged view of the vicinity, schematically illustrating the concept of electron emission from another electron-emitting device according to the present invention. The details will be described below. In this case, when a predetermined voltage is applied between the electrode portions 2 and 3 of the present electron-emitting device, the materials of the conductive layers 4a and b and the film 5 serving as the electron-emitting portion are appropriately selected, so that the conductive layer 4a A constant current also flows through the film 5 serving as an electron emission portion via the same. That is, the conductive layer 4
The electrons conducting through a and 4b are transmitted to the inside and the surface layer of the film 5 serving as the electron emitting portion, and a part thereof is taken out to the outside by an appropriate electric field to become the emitted electrons 7. That is, by arranging the film 5 serving as an electron emitting portion between the conductive layers 4a and 4b, a part of the current flowing between the conductive layers 4a and 4b can be uniformly extracted to the outside. Although not shown, by arranging another electrode for controlling the emitted electron flow at a position facing the substrate 1, acceleration of the emitted electrons 7 and control of the trajectory can be performed. Normally, the emitted electrons 7 can be obtained only by applying a current between the conductive layers as described above. However, by simultaneously heating the conductive layer and the film 5 serving as an electron emission portion, the heat energy is assisted, so that more efficient Electron emission is realized. Also in this case, the amount of emitted electrons can be modulated by controlling the amount of current flowing between the conductive layers 4a and 4b.

Similarly to the configuration of the above-mentioned first electron-emitting device, a plurality of pairs of conductive layers and electron-emitting layers are provided for a pair of electrode portions 2 and 3 as shown in FIGS. The films serving as the parts may be arranged in parallel.

Although electron emission can be obtained by the above-described element structure, in order to obtain more efficient electron emission characteristics, the material and size of the conductive layer to be used, the material of the film to be the electron emission portion, and the like are determined. The structure needs to be considered. That is, in order to obtain an efficient electron-emitting device, it is important to properly select a suitable material and structure.

Therefore, the present invention relates to the above-mentioned element structure,
It is preferable that the film serving as the electron emitting portion is made of diamond or a material containing diamond as a main component.

Further, in the present invention, it is preferable that the element structure has a structure in which the outermost surface atoms of a diamond film or a film containing diamond as an electron emission portion are terminated by bonding with hydrogen atoms. It is preferable that the bonded hydrogen atom weight be 1 × 10 ¹⁵ or more per square centimeter. More preferably, the amount of bonded hydrogen is 2 × 10 ¹⁵ / cm ² or more.

According to the present invention, in the above element structure, the diamond film serving as the electron emitting portion or the film containing diamond as a main component is preferably a layer having crystal defects, and the crystal defect density is 1 cubic centimeter. The number is preferably 1 × 10 ¹⁸ or more. More preferably, the crystal defect density is 1 × 10 ²⁰ / cm ³ or more.

As described above, in the device configuration of the present invention,
According to a preferred example in which a diamond film or a film containing diamond as a main component is used for the electron-emitting portion, diamond has a wide bandgap semiconductor (5.5 eV), high hardness, abrasion resistance, high thermal conductivity, Since it has very suitable properties as an electron emitting material such as inertness, it is possible to form a highly stable electron emitting portion.

Further, by making the surface state terminated by bonding with hydrogen atoms, it is possible to maintain a film surface more stable against electron emission. Further, since the surface of the diamond terminated with hydrogen is in a negative electron affinity state, it becomes possible to make the electron emission source very easy to emit electrons. The amount of bonded hydrogen atoms for obtaining such a stable surface is 1 × 10 ¹⁵ or more, preferably 2 × 10 ¹⁵ / cm ² or more per square centimeter, where almost all the outermost carbon atoms are bonded to hydrogen atoms. is there.

Since the diamond film or the film containing diamond as a main component has an appropriate amount of crystal defects, the amount of electrons transmitted from the conductive layer to the inside and the surface of the film can be increased. The amount of crystal defects is about 1 × 10 ¹⁸ / cm ³ or more, preferably 1 × 10 ²⁰ / cm ³ or more.

In the present invention, it is preferable that the conductive layer is made of any material selected from a metal and an n-type semiconductor. Among them, metals such as tungsten (W), platinum (Pt), and molybdenum (Mo)
And the like, and the n-type semiconductor is preferably a silicon-based amorphous semiconductor (a-Si, a-SiC, etc.), microcrystalline silicon (μc-Si), polycrystalline silicon (poly-Si), or the like. .

According to the present invention, in the above-mentioned element structure, it is preferable that the thickness of the conductive layer is 100 nm or less.

As described above, in the device configuration of the present invention,
According to a preferred example in which the conductive layer is formed of any material selected from a metal and an n-type semiconductor, it is possible to manufacture a conductive layer capable of flowing an appropriate amount of current. The range of the electrical resistivity of the conductive layer generally used is
Since it depends on the size of the conductive layer, it cannot be specified unconditionally, but is about 10 ⁻⁶ to 10 ⁴ Ω · cm.

According to a preferred embodiment in which the thickness of the conductive layer is 100 nm or less, electrons flowing in the conductive layer can be efficiently transmitted to the film serving as an electron emitting portion.

Further, in the present invention, it is preferable that in the device configuration, another electrode is provided at a position facing the film serving as the electron-emitting portion.

According to this preferred example, another electrode for controlling the emitted electron flow is disposed at a position opposite to the film serving as the electron emitting portion, so that the acceleration of the emitted electrons and the control of the trajectory are controlled. Becomes possible.

According to another aspect of the present invention, there is provided an electron emission source comprising: a plurality of the above-described electron emission devices capable of controlling the amount of each electron emission in accordance with an input signal; It is characterized by being arranged.

According to the electron emission source of the present invention, a large number of high-efficiency electron emission elements are provided, so that a large electron emission current can be obtained and the electron emission region can be widened.
Furthermore, since the amount of each electron emission is controlled according to the input signal, an arbitrary electron emission distribution can be obtained.

In order to achieve the above object, the structure of the phosphor light emitting device according to the present invention comprises at least a sealed container, a phosphor layer disposed inside the container, and a phosphor layer. A phosphor light emitting device comprising an electron emission source for irradiating an electron beam, wherein the electron emission source described above is used.

According to the phosphor light emitting device of the present invention, since the electron emission source of the present invention having high efficiency and stability is arranged, it is possible to emit the phosphor with high controllability and high luminance.

According to another aspect of the present invention, there is provided a method for manufacturing an electron-emitting device, comprising: an electrode portion, a conductive layer portion, and a diamond film serving as an electron-emitting portion or a film containing diamond as a main component. Wherein the step of forming the diamond film or the film containing diamond as a main component is a vapor phase synthesis step.

The present invention also provides the above method, wherein the step of vapor-phase synthesizing a diamond film or a film containing diamond as a main component comprises the step of distributing particulate diamond having an average particle size of 0.2 μm or less; A step of additionally growing diamond or a material containing diamond as a main component on the diamond-shaped diamond.

In the present invention, it is preferable that, in the step of distributing the particulate diamond, the particulate diamond is distributed using a solution in which diamond particles having an average particle diameter of 0.2 μm or less are dispersed.

As described above, in the production method of the present invention,
According to a preferred example, in which a diamond film or a film containing diamond as a main component is a vapor phase synthesis process, a high-quality diamond film, which is very suitable as an electron-emitting material, can be formed by controlling the manufacturing conditions. Since it can be formed on a layer or between conductive layers with good reproducibility, it is possible to easily form a highly efficient electron-emitting device. Vapor-phase synthesis method such as a generally diamond raw material gas a hydrocarbon gas _{(CH 4, C 2 H 6} , C 2 H 4, C 2 H 2 , etc.) or an organic compound (CH ₃ O
H, C ₂ H ₅ OH, CH ₃ COCH _3, etc.) and carbon monoxide (CO) diluted with hydrogen and decomposing the raw material gas. At that time, oxygen, water or the like can be added to the raw material gas as appropriate. In the present invention, the applicable gas phase synthesis method is not particularly limited, but a microwave plasma CVD method or a hot filament method is preferable. Further, a vapor phase synthesis step of a diamond film or a film containing diamond as a main component is a step of distributing particulate diamond having an average particle size of 0.2 μm or less, and a material containing diamond or diamond as a main component on the particulate diamond. According to a preferred example of the method, the nucleation of diamond or a material containing diamond as a main component during vapor phase synthesis can be controlled. The material can be formed. In the step of distributing the particulate diamond, the average particle size is 0.2 μm.
According to a preferred example of distributing the particulate diamond using a solution in which diamond particles having a diameter of m or less are dispersed, the particulate diamond to be a growth nucleus is arranged uniformly and with good controllability and reproducibility even for a large area. It is possible to do. The distribution position of the particulate diamond can be selected by appropriately selecting the distribution method. As a specific distribution method using the diamond particle dispersion solution, 1) application of the dispersion solution to the conductive layer, 2) ultrasonic vibration treatment in the dispersion solution, or 3) voltage application treatment in the solution solution, etc. But not limited to this. Also,
The amount of the particulate diamond dispersed in the diamond dispersion solution used is 0.01 to 20 per liter of the solvent.
g. The number of diamond particles dispersed in the dispersion solution is 1 × 10 ¹⁶ to 1 / liter of the solution.
It is suitable that the number is about × 10 ²⁰ pieces. At this time, it is suitable that water or alcohol is a main component as a solvent of the dispersion solution.

In order to achieve the above object, a method of manufacturing an electron-emitting device according to the present invention is directed to a method of manufacturing an electron-emitting device comprising an electrode portion, a conductive layer, and a diamond film serving as an electron-emitting portion or a film containing diamond as a main component. A manufacturing method,
A step of introducing crystal defects into the diamond film or the film containing diamond as a main component.

In the present invention, it is preferable that, in the above-mentioned manufacturing method, the step of providing crystal defects in the diamond film or the film containing diamond as a main component is a step of irradiating accelerated atoms.

As described above, in the production method of the present invention,
A step of introducing crystal defects into a diamond film or a film containing diamond as a main component, the electron emission characteristics of a diamond film or a film containing diamond as a main component disposed on or between conductive layers. Can be improved, so that a more efficient electron-emitting device can be formed. In this case, according to a preferred example in which the step of providing crystal defects in the diamond film or the film containing diamond as a main component is a step of irradiating accelerated atoms, the amount of crystal defects in the film for improving electron emission characteristics is controlled. It can be formed well.

In order to achieve the above object, a method of manufacturing an electron-emitting device according to the present invention is directed to a method of manufacturing an electron-emitting device comprising an electrode portion, a conductive layer and a diamond film serving as an electron-emitting portion or a film containing diamond as a main component. A manufacturing method,
A step of bonding a hydrogen atom to an outermost surface atom of the diamond film or the film containing diamond as a main component.

Further, according to the present invention, in the above-mentioned manufacturing method, the step of bonding a hydrogen atom to the outermost surface atom of the diamond film or the film containing diamond as a main component may be a step of heating to 600 ° C. or more in an atmosphere containing hydrogen, or Is 200nm
It is preferable to select from the following steps of irradiating ultraviolet light.

As described above, in the production method of the present invention,
A step of bonding hydrogen atoms to the outermost surface atoms of the diamond film or the film containing diamond as a main component, the electron emission of the diamond film or the film containing diamond as a main component disposed on the conductive layer. Since the characteristics can be improved, it is possible to form the electron-emitting device with higher efficiency. At this time, the step of bonding hydrogen atoms to the outermost surface atoms of the diamond film or the film containing diamond as a main component is performed in an atmosphere containing hydrogen.
According to a preferred example of a step of heating to 0 ° C. or higher or a step of irradiating ultraviolet light having a wavelength of 200 nm or less,
Hydrogen atoms can be easily bonded to the surface of diamond or a film containing diamond as a main component. As a result, it becomes possible to easily emit electrons.

[0054]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described more specifically with reference to examples.

<First Embodiment> The result of fabricating an electron-emitting device according to the present invention using the process of FIG. 6 will be described. In the present embodiment, a vapor-phase synthetic diamond film is used as a film serving as an electron emitting portion.

First, the base material 61 is prepared. The material used for the substrate is not particularly limited as long as it is insulating. In this example, quartz glass was used (FIG. 6A).

Next, an n-type microcrystalline silicon (μc-Si) layer having a thickness of 200 nm was formed as a conductive layer 62 on the quartz glass substrate. In the present embodiment, μ
A c-Si layer was deposited, but not limited to this (FIG. 6 (b)).

Subsequently, the μc-Si layer was patterned by a usual photolithography step and an etching step. The pattern size is appropriately selected, but in this embodiment, the width (W) is
A rectangular pattern having a length of 100 μm and a length (L) of 10 μm was formed (FIG. 6C).

Then, a resist layer 63 is coated on the element surface.
After that, the area where the diamond film to be the electron emission part is formed
Use the photolithography process again to select
Open a window of 120μm wide and 5μm long at the center of the conductive layer
Was. (FIG. 6 (d)) Then, the average particle size is 0.02
A solution in which μm diamond particles were dispersed was applied.
In this embodiment, 1 g of diamond is added to 1 liter of pure water.
The solution in which the powder particles were dispersed was used. The application of the dispersion solution
A spin coating technique was used. After application, the substrate is
It was dried by irradiation with pump light. This diamond grain
Observation of the surface of the conductive layer 62 coated with the electron microscope with a scanning electron microscope
As a result, the fine diamond grains mixed with the dispersion
It turned out that they are distributed uniformly. Also, its distribution density
Is ~ 5 × 10 ^TenPieces / cm^TwoIt was about.

Then, a diamond film is further formed on the conductive layer on which the fine diamond particles are distributed by a vapor phase synthesis method.
Formed 64. The method for synthesizing the diamond film is not particularly limited, but in this example, the diamond film was formed by a microwave plasma CVD method. Microwave plasma C
The VD method is a method of forming a diamond by applying a microwave to a source gas to form diamond. As a specific condition, the raw material gas is hydrogen (H ₂ ) 1
Carbon monoxide (CO) gas diluted to 1010 vol% was used.
The reaction temperature and pressure are 800-900 ° C and 25-40 Torr, respectively.
It is.

As a result of forming a diamond film on the conductive layer by the above method, it was confirmed that the diamond film (thickness: 200 nm) was grown only in the region where the diamond particles were distributed. (FIG. 6E) Further, an aluminum layer (Al) to be the electrode portion 65 was formed at both ends of the conductive layer 62 (FIG. 6F).

The characteristics of the electron-emitting device manufactured by the above-described method were examined using the measurement and evaluation apparatus shown in FIG. First, the electron-emitting device 81 was placed in a vacuum chamber 82 and evacuated to a pressure of 1 × 10 ⁻⁷ Torr or less. Then, while a voltage of 1 kV is applied by an anode power supply 84 to an anode electrode 83 arranged at a distance of 1 mm from the electron-emitting device 81, a voltage of 10 V is applied between the electrodes of the electron-emitting device 81 by a power supply 86. The device current and the electron emission current flowing through the
Measured at 85. As a result, the conductive layer of the electron-emitting device 81
A device current of about 0 μA flowed, and an electron emission current of 1 μA was detected from the electron emission portion. That is, it was confirmed that electrons were emitted from the diamond film disposed on the electron-emitting device 81. When the voltage applied to the device was changed in the range of 1 to 30 V, it was observed that the electron emission current value changed according to the amount of current flowing through the conductive layer. At this time, the efficiency of the electron emission current extracted to the outside with respect to the current flowing through the device was about 1%.

In the diamond film forming step of the present embodiment, the diamond particles were obtained by directly scattering the diamond particles on the conductive layer without using the particle diamond dispersion solution, or by using another distribution method using the dispersion solution. Similar results were obtained for the diamond film.

Further, in the present embodiment, similar results were obtained when another material that easily emits electrons, such as particulate boron nitride (BN), was used as the electron-emitting portion.

Further, the present inventors installed a control electrode for controlling the trajectory of the emitted electron current between the electron-emitting device 81 and the anode electrode 83, and applied a voltage to this control electrode to It has been confirmed that the trajectory of the emitted electron stream can be changed or focused.

<Comparative Example 1> When a similar anode voltage was applied to the electron-emitting device manufactured in the first embodiment in a state where no voltage was applied, that is, in a state where current did not flow through the conductive layer. Electron emission was confirmed using the apparatus of FIG. 8, but no electron emission current was detected.

<Comparative Example 2> An element having the same element configuration as that of the first embodiment, in which a voltage of 10 V is applied between electrodes of a comparative sample manufactured without forming a diamond film on a conductive layer, and flows at that time. The current and the electron emission current were measured, respectively. As a result, the same device current as in the first embodiment flowed through the conductive layer of the device, but no electron emission current was detected.

<Second Embodiment> Similar to the first embodiment, the result when the material of the conductive layer is changed in the electron-emitting device formed on the quartz glass substrate will be described.

The base material used, the diamond film used as the electron emitting portion, the method for forming the same, and the like are the same as those in the first embodiment. In this embodiment, a tungsten (W) layer formed by an electron beam evaporation method was used as a material of the conductive layer. The film thickness was 100 nm. As in the previous embodiment, W
The layers were patterned by the usual photolithography and etching steps. The pattern size of the conductive part is the width
(W) is a rectangular pattern having a length of 10 μm and a length (L) of 200 μm. In this embodiment, since the conductive layer itself is a metal and it is not necessary to form an electrode again, a pattern in which the wiring pattern (□ 500 μm) serving as an electrode part is also formed at both ends of the rectangular pattern is formed. . Then, a diamond film was formed on a part of the conductive layer (W layer).

The characteristics of the electron-emitting device manufactured by the above-described method were examined using the measurement and evaluation apparatus shown in FIG. The evaluation conditions are the same as in the first embodiment. As a result, when a voltage of 1 V was applied to the conductive layer of the electron-emitting device 81, a device current of about 40 mA flowed, and an electron emission current emitted from the electron-emitting portion was detected as 40 μA. That is, it was confirmed that electrons were emitted from the diamond film disposed on the electron-emitting device 81. When the voltage applied to the element was changed, it was observed that the electron emission current value changed according to the amount of current flowing through the conductive layer. At this time, the efficiency of the electron emission current extracted to the outside with respect to the current flowing through the device is about 0.
1%.

Next, the conductive layer made of W was heated to 350 ° C. As a result, emission of electrons was facilitated with the help of thermal energy, and the emission efficiency was improved to about 0.5%.

In the present embodiment, even when the diamond particles are directly scattered on the conductive layer without using the particulate diamond dispersion solution, or when the diamond film is formed by another distribution method using the dispersion solution, Similar results were obtained.

Further, in the present embodiment, similar results were obtained even when another material that easily emits electrons, such as boron nitride (BN), was used as the electron emitting portion.

<Third Embodiment> Next, a description will be given of a result of a case where post-processing is performed on the formed diamond film in the first embodiment.

The base material to be used, the material of the conductive layer, the method of forming the diamond film used as the electron emitting portion, and the like are the same as those in the first embodiment. Therefore, after a diamond film was formed in the same manner as in the above embodiment, the diamond film was subjected to a heat treatment at 600 ° C. for 3 hours in a hydrogen atmosphere.

The conductive layer on the conductive layer obtained by the above method
The surface of the diamond film is terminated with bonding to hydrogen atoms.
It was confirmed that. Its hydrogen atomic weight is 1.5 × 10^Fifteen
Pieces / cm ^TwoIt was about. In addition, both ends of the conductive layer become electrodes
An aluminum layer (Al) was formed.

The characteristics of the electron-emitting device manufactured by the above-described method were examined using the measurement and evaluation apparatus shown in FIG. The evaluation conditions are the same as in the first embodiment. As a result, when a voltage of 10 V was applied to the conductive layer of the electron-emitting device 81, a device current of about 100 μA flowed, and 1.5 μA of the electron emission current emitted from the electron-emitting portion was detected. That is, it was confirmed that the electron emission was more efficiently performed by controlling the surface state of the diamond film than in the first embodiment.

<Fourth Embodiment> Next, a description will be given of a result of a case where post-processing is performed on the formed diamond film in the first embodiment.

The base material used, the material of the conductive layer, the method of forming the diamond film used as the electron emitting portion, and the like are the same as those in the first embodiment. Therefore, after a diamond film was formed in the same manner as in the above embodiment, ions were implanted into the diamond film to introduce crystal defects into the diamond layer. In this embodiment, carbon (C) or boron (B) ions are converted to 1 × 10 ¹⁴ ions at an energy of 40 to 200 keV.
Irradiation was performed at about pieces / cm ² .

The diamond film on the conductive layer obtained by the above method had crystal defects of about 1 × 10 ²⁰ / cm ³ . Further, an aluminum layer (Al) serving as an electrode was formed at both ends of the conductive layer.

The characteristics of the electron-emitting device manufactured by the above-described method were examined using the measurement and evaluation apparatus shown in FIG. The evaluation conditions are the same as in the first embodiment. As a result, when a voltage of 10 V was applied to the conductive layer of the electron-emitting device 81, a device current of about 100 μA flowed, and 2 μA of the electron emission current emitted from the electron-emitting portion was detected. That is, it was confirmed that electron emission was more efficiently performed by controlling the state of the diamond film than in the first embodiment.

<Fifth Embodiment> The result of fabricating another electron-emitting device according to the present invention using the process of FIG. 7 will be described. Also in the present embodiment, a vapor-phase synthetic diamond film was used as a film serving as an electron emitting portion.

First, the base material 71 is prepared. The material used for the substrate is not particularly limited as long as it is insulating. In this example, quartz glass was used (FIG. 7A).

Next, on the quartz base material, n
A microcrystalline silicon (μc-Si) layer having a shape of 200 nm was formed (FIG. 7B).

Subsequently, the μc-Si layer is patterned to have a width (W).
A pair of rectangular patterns each having a length of 100 μm and a length (L) of 5 μm were formed (FIG. 7C).

After the resist surface 73 is coated on the element surface, in order to select a region for forming a diamond film to be an electron emitting portion, a photolithography process is again performed so that a width of 120 μm and a length of 120 μm are provided so as to extend over the conductive layers. 5 μm
Opened the window. (FIG. 7 (d)) Then, a solution in which diamond particles having an average particle size of 0.02 μm were dispersed was applied to the region. In this embodiment, a solution in which 1 g of diamond particles is dispersed in 1 liter of pure water is applied by a spin coating technique. After the application, the substrate was dried by irradiation with infrared lamp light. When the surface of the conductive layer coated with the diamond particles was observed with a scanning electron microscope, it was found that the fine diamond particles contained in the dispersion were uniformly distributed. The distribution density is up to 5 × 10 ¹⁰
/ cm ² .

Then, a diamond film 74 was formed on the conductive layer in which the fine diamond particles were distributed by microwave plasma CVD, which is a kind of vapor phase synthesis. The specific forming conditions are the same as in the first embodiment.

As a result of forming a diamond film on a conductive layer by the above-described method, a diamond film grows only in a region where diamond particles are distributed, and an element structure in which a pair of conductive layers is connected by a diamond layer is obtained. Was. (FIG. 7
(e)) Further, an aluminum layer (Al) to be the electrode layer 75 was formed on both ends of the conductive layer (FIG. 7 (f)).

The characteristics of another electron-emitting device manufactured by the above-described method were examined using the measurement and evaluation apparatus shown in FIG. The evaluation conditions are the same as in the first embodiment. As a result, when a voltage of 10 V was applied to the conductive layer of the electron-emitting device 81, 50 μA
About 2 μA of an electron emission current emitted from the electron emission portion was detected. That is, it was confirmed that electrons were emitted from the diamond film disposed on the electron-emitting device 81. The voltage applied to the element is
When it was changed in the range of 30 V, it was observed that the electron emission current value changed according to the amount of current flowing through the conductive layer. At this time, the efficiency of the electron emission current extracted to the outside with respect to the current flowing through the device was about 3%.

In the present embodiment, even when the diamond particles are directly scattered on the conductive layer without using the diamond dispersion solution, or when the diamond film is formed by using another distribution method using the dispersion solution. And similar results were obtained.

Further, in the present embodiment, similar results were obtained even when another material that easily emits electrons, such as particulate boron nitride (BN), was used as the electron emitting portion.

Further, the present inventors set a control electrode for controlling the trajectory of the emitted electron current between the electron-emitting device 81 and the anode electrode 83, and applied a voltage to this control electrode to It has been confirmed that the trajectory of the emitted electron stream can be changed or focused.

<Comparative Example 3> A similar anode voltage was applied to the electron-emitting device manufactured in the fifth embodiment in a state where no voltage was applied, that is, in a state where current did not flow through the conductive layer and the diamond film. The electron emission at this time was confirmed using the apparatus shown in FIG. 8, but no electron emission current was detected.

<Sixth Embodiment> 10 × 10 samples prepared in the first embodiment are arranged on the same substrate, and the total amount of emitted electrons is determined by using the voltage applied to each electrode as an input signal. An electron emission source for controlling the electron emission was fabricated. As a result, the amount of electron emission can be modulated by changing the number of elements that provide a voltage as an input signal, or by changing the voltage applied to the element, and the electron emission source must be more efficient than in the past. Could be confirmed. Also, the change with time of the electron emission amount was small. Also, if input signals with distribution are given to 10 vertical and 10 horizontal electron emission element arrays,
It was also confirmed that an electron emission distribution corresponding to the signal distribution was obtained.

<Seventh Embodiment> Using the electron emission source manufactured in the sixth embodiment, a phosphor light emitting device for emitting a phosphor was manufactured. As a result, it was confirmed that the phosphor can emit light with low power consumption because the electron emission source is more efficient than the conventional one. The stability (change with time) was also good.

[0096]

As described above, according to the electron-emitting device of the present invention, at least a plurality of electrodes, a conductive layer on which the electrodes are disposed, and a film serving as an electron-emitting portion are disposed on the conductive layer. Therefore, electron emission can be performed efficiently and highly stable electron emission can be obtained.

According to the electron-emitting device of the present invention,
Since at least a plurality of electrodes and a film serving as an electron emitting portion are arranged between the conductive layers on which the electrodes are arranged, it is possible to efficiently emit electrons and obtain highly stable electron emission. It becomes possible.

According to the structure of the present invention, the film thickness is 1
Since the thickness is not more than μm, electrons can be efficiently extracted to the outside.

Further, according to the structure of the present invention, since the current is applied in the in-plane direction of the conductive layer or the conductive layer is heated while applying the current, the electron emitting portion can be easily applied to the conductive layer. Electrons can be transmitted.

Further, according to the structure of the present invention, since the amount of current flowing in the in-plane direction of the conductive layer is controlled, signal modulation with a low driving voltage is possible.

According to the structure of the present invention, the film serving as the electron-emitting portion is characterized by being made of diamond or a material containing diamond as a main component, so that the electron-emitting portion has high stability. It becomes possible.

Further, according to the structure of the present invention, the diamond film serving as the electron-emitting portion or the film containing diamond as a main component has a structure in which the outermost surface atoms are terminated by bonding with hydrogen atoms, and preferably the bonded hydrogen since, wherein the atomic weight of from 1 × 10 ^{1 5} or more per square centimeter, it is possible to maintain a more stable surface for electron emission.

According to the structure of the present invention, the diamond film serving as the electron emitting portion or the film containing diamond as a main component is a layer having crystal defects, and preferably has a crystal defect density of 1 per cubic centimeter. Since it is characterized by having × 10 ¹⁸ or more, the amount of electrons transmitted from the conductive layer to the surface of the film can be increased.

Further, according to the structure of the present invention, since the conductive layer is made of any material selected from the group consisting of metal and n-type semiconductor, the conductive layer is capable of supplying an appropriate amount of current. Layers can be made.

Further, according to the structure of the present invention, since the thickness of the conductive layer is 100 nm or less, electrons flowing in the conductive layer can be efficiently transmitted to the electron-emitting portion.

Further, according to the structure of the present invention, since another electrode is provided at a position opposite to the film serving as the electron emitting portion, the trajectory and beam diameter of the emitted electron flow can be controlled. Becomes possible.

Further, according to the electron emission source of the present invention, a plurality of the above-mentioned electron emission elements whose individual electron emission amounts can be controlled according to an input signal are arranged on a flat substrate. Therefore, high-efficiency electron-emitting devices save power,
In addition, it is possible to widen the electron emission region. Further, since the amount of each electron emission can be controlled according to the input signal, it is possible to obtain an arbitrary electron emission distribution.

According to the electron emission source of the present invention, at least a sealed container, a phosphor layer disposed inside the container, and an electron emission source for irradiating the phosphor layer with an electron beam. A phosphor light-emitting device comprising the above-described electron emission source, so that the phosphor can emit light with high controllability and high luminance.

Further, according to the method for manufacturing an electron emission source according to the present invention, there is provided a method for manufacturing an electron emission element comprising a diamond film serving as an electrode portion, a conductive layer portion and an electron emission portion or a film containing diamond as a main component. Since the step of forming the diamond film or the film containing diamond as a main component is performed by a gas phase synthesis method, an electron emission portion made of high-quality diamond can be easily formed.

Further, according to the present invention, the vapor phase synthesizing step of a diamond film or a film containing diamond as a main component is carried out by:
A step of additionally growing diamond on the particulate diamond, so that diamond very suitable as an electron-emitting material can be easily arranged on the conductive layer or between the conductive layers with good reproducibility. An efficient electron-emitting device can be formed.

Further, according to the method of the present invention, in the step of distributing the particulate diamond, a solution in which diamond particles having an average particle diameter of 0.2 μm or less are used is used. Since the diamond particles can be arranged uniformly and with good controllability and reproducibility,
It is possible to easily reduce the thickness of the vapor phase synthetic diamond.

According to the method of the present invention, a diamond film or a film containing diamond as a main component is subjected to a heat treatment at 600 ° C. or more in an atmosphere containing hydrogen gas.
Alternatively, since the accelerated particles are irradiated, the electron emission characteristics of diamond used as the electron emission portion are improved.

[Brief description of the drawings]

FIG. 1A is a schematic plan view showing a basic structure of an electron-emitting device according to the present invention. FIG. 1B is a schematic cross-sectional view showing a basic structure of an electron-emitting device according to the present invention.

FIG. 2 is an enlarged view of the vicinity of a film serving as an electron-emitting portion of the electron-emitting device according to the present invention, schematically showing the concept of electron emission.

FIG. 3 is a schematic plan view showing a basic structure when a plurality of electron-emitting devices according to the present invention are arranged in parallel with respect to a pair of electrode portions.

4A is a schematic plan view showing a basic structure of another electron-emitting device according to the present invention. FIG. 4B is a schematic cross-sectional view showing a basic structure of another electron-emitting device according to the present invention.

FIG. 5 is an enlarged view of the vicinity of a film serving as an electron-emitting portion of another electron-emitting device according to the present invention, schematically showing the concept of electron emission.

FIG. 6 is a schematic view showing a process for forming an electron-emitting device according to the present invention.

FIG. 7 is a schematic view showing a process for forming another electron-emitting device according to the present invention.

FIG. 8 is a schematic diagram of an apparatus for measuring and evaluating the electron emission characteristics of the electron-emitting device according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 base material 2, 3 electrode 4, 4 a, 4 b conductive layer 5 film serving as electron emitting portion 6 electron 7 emitted electron 61 base material (quartz glass) 62 conductive layer (n-type μc-Si) 63 resist layer 64 electron emitting portion Film (diamond film) 65 Electrode (Al) 71 Base material (quartz glass) 72 Conductive layer (n-type μc-Si) 73 Resist layer 74 Film (diamond film) to be electron emission part 75 Electrode (Al) 81 Electron-emitting device 82 Vacuum chamber 83 Anode electrode 84 Anode power supply 85 Ammeter 86 Power supply 87 Ammeter

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Tetsuya Shiratori 1006 Kazuma Kadoma, Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd.

Claims (23)

[Claims] 1. An electron-emitting device in which at least a plurality of electrode portions, a conductive layer on which the electrode portions are disposed, and a film serving as an electron-emitting portion are disposed on the conductive layer. 2. An electron-emitting device in which at least a plurality of electrode portions, a plurality of conductive layers on which the electrode portions are disposed, and a film serving as an electron-emitting portion are disposed between the conductive layers. 3. The electron-emitting device according to claim 1, wherein the thickness of the film is 1 μm or less. 4. The electron-emitting device according to claim 1, wherein a current is applied in an in-plane direction of the conductive layer. 5. The conductive layer is heated while applying a current in an in-plane direction of the conductive layer.
3. The electron-emitting device according to item 1. 6. The electron-emitting device according to claim 1, wherein the amount of electron emission is modulated by controlling the amount of current flowing in the in-plane direction of the conductive layer. 7. The electron-emitting device according to claim 1, wherein the film serving as the electron-emitting portion is made of diamond or a material containing diamond as a main component. 8. The electron-emitting device according to claim 7, wherein the outermost surface atoms of diamond or a film containing diamond as a main component have a structure terminated by bonding with hydrogen atoms. 9. The amount of hydrogen atoms bonded to the outermost surface atoms of diamond or a film containing diamond as a main component is 1
9. The electron-emitting device according to claim 8, wherein the number is 1 × 10 ¹⁵ or more per square centimeter. 10. The electron-emitting device according to claim 7, wherein the diamond or the film containing diamond as a main component has a crystal defect. 11. The crystal defect density of diamond or a film containing diamond as a main component is 1 × 10 ¹⁸ or more per cubic centimeter.
The electron-emitting device according to 0. 12. The electron-emitting device according to claim 1, wherein the conductive layer is made of any material selected from a metal and an n-type semiconductor. 13. The electron-emitting device according to claim 1, wherein the conductive layer has a thickness of 100 nm or less. 14. The device according to claim 1, wherein another electrode is provided at a position opposite to the film serving as an electron emitting portion.
Or the electron-emitting device according to 2. 15. An electron emission source, wherein a plurality of electron emission devices according to claim 1 or 2 are arranged on a plane substrate, wherein the electron emission amount can be controlled according to an input signal. 16. A phosphor light emitting device comprising at least a sealed container, a phosphor layer disposed inside the container, and an electron emission source for irradiating the phosphor layer with an electron beam, 16. A phosphor light emitting device, wherein the electron emission source has a configuration according to claim 15. 17. A method for manufacturing an electron-emitting device comprising a diamond film serving as an electrode portion, a conductive layer portion and an electron-emitting portion or a film containing diamond as a main component, wherein said diamond film or a film containing diamond as a main component. Wherein the step of forming is a vapor phase synthesizing step. 18. A method for producing a diamond film or a film containing diamond as a main component, comprising the steps of: distributing particulate diamond having an average particle size of 0.2 μm or less; and depositing diamond or diamond on the particulate diamond. 18. The method for manufacturing an electron-emitting device according to claim 17, further comprising: a step of additionally growing a material as a main component. 19. The method according to claim 18, wherein in the step of distributing the particulate diamond, the particulate diamond is distributed using a solution in which diamond particles having an average particle size of 0.2 μm or less are dispersed. A method for manufacturing an emission element. 20. A method for manufacturing an electron-emitting device comprising an electrode portion, a conductive layer and a diamond film serving as an electron-emitting portion or a film containing diamond as a main component. A method for manufacturing an electron-emitting device, comprising a step of introducing a crystal defect. 21. The electron-emitting device according to claim 20, wherein the step of introducing a crystal defect into the diamond film or the film containing diamond as a main component is a step of irradiating accelerated atoms or molecules. Production method. 22. A method of manufacturing an electron-emitting device comprising an electrode portion, a conductive layer, and a diamond film serving as an electron-emitting portion or a film containing diamond as a main component. A method for manufacturing an electron-emitting device, comprising a step of bonding a hydrogen atom to an outermost surface atom. 23. A step of bonding a hydrogen atom to the outermost surface atom of the diamond film or the film containing diamond as a main component, wherein the heating is performed at 600 ° C. or more in an atmosphere containing hydrogen, 23. The method for producing an electron-emitting device according to claim 22, wherein the method is selected from a step of irradiating the electron-emitting device.