JP2003178669A - Method of manufacturing cold cathode device, cold cathode device, and display device using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cold cathode device improving electron emission efficiency in addition to keeping chemical stability of carbon in electron emission. <P>SOLUTION: This manufacturing method for the cold cathode device having a cathode bus formed on a substrate and a field emission cold cathode made from a carbon base material electrically connected to the cold cathode bus comprises a process forming the cold cathode bus on the substrate; a process forming the carbon base material layer containing graphite as the main component and electrically connected to the cold cathode bus; and a process introducing impurity atoms or molecules having a work function smaller than that of the graphite into the carbon base material layer and forming the field emission cold cathode. <P>COPYRIGHT: (C)2003,JPO

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 and a method for manufacturing a cold cathode device, and more particularly to cooling a carbon-based material containing graphite (graphite), which is a plate-like crystal belonging to the hexagonal system, as a main component material. The present invention relates to a technique effective when applied to a cold cathode device which is a cathode (field emission cold cathode).

[0002]

2. Description of the Related Art A conventional typical cold cathode is a spin cathode in which a voltage is applied between a cathode having a sharp cone-shaped tip and a gate electrode which surrounds it, and electrons are emitted from the cathode tip by an electric field. The structure called a mold was common. The electron emission efficiency of the Spindt-type cold cathode device is largely influenced by the concentration of the electric field formed on the cathode surface and various characteristics such as the work function φ of the cathode material and surface physical properties.

Since the electric field concentration of the Spindt-type cold cathode device is determined by the sharpness of the cathode and the distance between the cathode and the gate electrode, a great improvement in efficiency is achieved by improving the precision of a fine processing technique centered on lithography and further reducing the size. It depended on the progress of technology.

As a cold cathode that does not require such fine processing, a MIM type (Metal / lnsulator /
Metal), MIS type (Metal / Insulat)
or / Semiconductor). In the surface emission type cold cathode device, a combination of materials and improvement of electron emission efficiency have been problems.

On the other hand, high melting point metals such as molybdenum (Mo) and nickel (Ni) and semiconductors such as silicon have been mainly used as cold cathode materials, but in these materials, work function φ = 4 to 5 eV or so. Therefore, a material having a lower work function has been sought. On the other hand, diamond or diamond-like carbon (DLC: Diamond)
-Like Carbon), aluminum nitride (AlN), or boron nitride (BN) has a negative electron affinity (NEA: Negative Electron Af).
It is also said to have the property of "finity", and it is considered to be promising as a cold cathode material in combination with its high hardness performance and chemical stability.

On the other hand, in recent years, it has been said that carbon nanotubes or carbon nanofibers exhibit excellent electron emission characteristics. However, clear NEA characteristics or high-efficiency electron emission characteristics have not yet been found for cold cathodes using these materials, and their practical application is hindered.

As a technique for improving electron emission characteristics, a method of adsorbing impurity atoms on the material surface is known. For example, on the surface of a tungsten single crystal, Cs (cesium), B
a (barium), U (uranium), I ₂ (iodine), Br
It is known that the work function φ can be significantly reduced by adsorbing ₂ (bromine), Cl ₂ (chlorine), and the like. this is,
This is due to the movement of electrons between the adsorbed species and the W single crystal substrate. However, with this method, the impurities adsorbed on the surface are unstable, and it is considered difficult to use it in a vacuum device such as a display or an image sensor.

[0008]

SUMMARY OF THE INVENTION The present inventor
As a result of examining the technology, the following problems were found. Cold shade
Diamond bonding, which is expected to have the highest performance as a polar material
The crystal is usually CH _Four(Methane), C_TwoH_Two(Acetile
Carbon dioxide, etc. and carbon monoxide CO as raw materials
, Chemical vapor deposition (CVD: Chemical Vapo)
r Deposition) or the like. However
However, in this method, the substrate is heated to a temperature of about 800 ° C or higher.
Hold the temperature to decompose the above raw materials, and
It is difficult to process on a large area because it grows crystals.
It was Especially in diamond, the diffusion coefficient of atoms is very high.
Small, generally with a growth rate of the order of 0.1 μm / hour
There was a problem of being small.

On the other hand, diamond-like carbon has characteristics similar to those of diamond even though it is amorphous carbon, so that it is advantageous for processing a large area. Deposited DL
The C film may be used as a thin film cold cathode as it is, but a cold cathode cone composed of a cathode having a sharp tip such as Mo (molybdenum) or silicon in advance and a gate electrode surrounding the cathode via an insulator is produced. Incidentally, there has been attempted a method of depositing a DLC film (or a polycrystalline diamond film) on the tip of the cathode from above the cathode by the above-mentioned CVD method or the like and coating the surface thereof. In addition, a method has also been attempted in which a pyramid-shaped depression is formed in advance on a substrate made of silicon, DLC or polycrystalline diamond is deposited on the depression by CVD, and then the substrate is removed. However, even when such a coating method is used, as described above, it is necessary to keep the substrate cold cathode at a high temperature of 800 ° C. or higher, and the surface layer contains a large number of defects. There was a problem that it was an amorphous layer. That is, since the characteristics of the cold cathode are largely influenced by the state of the surface layer, such a structure of the surface layer is unstable and is not preferable.

On the other hand, as a low temperature manufacturing method of these materials,
A laser ablation method has also been attempted in which a graphite target is irradiated with a strong laser beam to evaporate carbon atoms, molecules, ions, clusters and the like and deposit them on a substrate. ArF (wavelength: 19
3 nm), KrF (wavelength: 256 nm) or other excimer laser pulse light is used. However, there is also a report that the size of diamond crystals that can be produced by this method is very small and that they are DLC. Such a DLC film is composed of sp ² bonds and sp ³ bonds. The reason why DLC has not yet performed sufficiently as a cold cathode is that the relationship between the electron emission characteristics and the ratio of these bonds and the structure and properties of other materials is not yet clear. Recent studies have revealed that sp ² bonds play an important role in the electron emission properties of DLC. Therefore, a technique for controlling this sp ² bonded phase (region) is required, but a method for realizing highly efficient electron emission efficiency at low temperature has not been found for both diamond and DLC. However, since these carbon-based materials have the advantage that they are stable to an electron emission environment and do not require a high degree of vacuum for stable operation, it is possible to form a cold cathode of a carbon-based material at low temperature and There is a demand for development of a technology capable of achieving an efficient electron emission efficiency.

Further, Cs, Ba, U, I ₂ , Br ₂ , C
In the method of depositing l ₂ or the like on the surface of the metal cold cathode to improve the electron emission characteristics, as described above, not only is it unstable and difficult to make into a device, but it also brings about the maximum effect of reducing the work function φ. There is an optimum concentration, and even if these elements are deposited on the surface layer of the cold metal cathode, the effect cannot be improved, and the work function reducing effect is limited.

It is an object of the present invention to provide a cold cathode device capable of improving the electron emission efficiency while making the most of the chemical stability of carbon in electron emission. The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0013]

Among the inventions disclosed in the present application, a brief description will be given to the outline of typical ones.
It is as follows.

(1) In a method of manufacturing a cold cathode device having a cathode bus bar formed on a substrate and a field emission cold cathode made of a carbon-based material electrically connected to the cathode bus bar, the method is as follows: Forming a cathode busbar, forming a carbon-based material layer electrically connected to the cathode busbar by using the graphite as a main component material, and forming an impurity atom or molecule having a work function smaller than that of the graphite. Forming a field emission cold cathode by introducing it into the carbon-based material layer.

(2) In a cold cathode device having a cathode bus bar formed on a substrate and a field emission cold cathode made of a carbonaceous material electrically connected to the cathode bus bar, the cathode bus bar is electrically connected to the cathode bus bar. A carbon-based material layer made of a carbon-based material is formed so as to be connected, and a region in which an impurity atom or a molecule is introduced is formed between the plate-like crystals of the carbon-based material layer. A field emission cold cathode is formed.

(3) A cold cathode device in which a plurality of field emission cold cathodes are formed and a phosphor anode are arranged to face each other, and a voltage applied between the field emission cold cathode and the phosphor anode is controlled. In a display device for displaying an image according to an image signal, the cold cathode device is formed with a carbon-based material layer made of a carbon-based material so as to be electrically connected to a cathode bus bar formed on a substrate. At the same time, a plurality of regions in which impurity atoms or molecules are introduced are formed between the plate-like crystals of the carbon-based material layer, and the impurity-introduced regions form field emission cold cathodes.

According to the above-mentioned means (1), a step of forming a cathode bus bar on the substrate, a step of forming a carbon-based material layer containing graphite as a main component material and electrically connected to the cathode bus bar, The process of introducing an impurity atom or molecule having a work function smaller than that of graphite into the carbon-based material layer to form a field emission cold cathode, and the work of graphite to form the carbon-based material layer as shown in the following principle section. Since the function (about 5 eV) can be made close to the work function of the impurity atom or molecule smaller than the work function of graphite, the carbon-based material layer can be used as a field emission cold cathode.

At this time, since the impurity atoms or molecules are introduced (intercalated) into graphite, the chemical stability of carbon in electron emission is utilized, and highly efficient and selective electron emission characteristics are obtained. Obtainable.

(Principle) The structure of the cold cathode device according to the present invention will be described with reference to FIG. However, in FIG.
Is a carbon atom, 102 is an intercalation atom, 10
Reference numeral 3 indicates an emitted electron.

As shown in FIG. 1, the cold cathode of the cold cathode device of the present invention has a carbon atom 101 which is annularly bonded in the same plane.
Crystals of a layered structure (hereinafter referred to as "graphite layered crystal") formed by connecting a plurality of carbon atoms are formed, and each carbon atom 1
During 01, atoms or molecules that become impurities are introduced (intercalated). That is, the cold cathode of the cold cathode device of the present invention makes use of chemical stability of carbon in electron emission by introducing (intercalation) impurity atoms or molecules having a small work function between the layers of the graphite layered crystal. The structure is such that highly efficient and selective electron emission characteristics are obtained.

Generally, the work function of graphite is ~ 5.
Since it is about eV, it is not used as a cold cathode material. On the other hand, when carbon forms a compound with Cs, Ba, etc., the compound shows a work function rather close to that of Cs, Ba. Therefore, instead of adsorbing these alkali metals on the surface, in the present invention, between the layers of the graphite layered crystal formed by the plurality of carbon atoms 101,
By introducing an impurity atom or molecule as the intercalation atom 102, both chemical stability of the carbon surface at the time of emitting the emitted electron 103 from the graphite layered crystal and reduction of the work function by intercalation were made compatible. It forms a cold cathode.

That is, it differs from the graphite layer structure having vertical stacks of carbon atoms 101 having a very large interval (periodic interval) as compared with the interval between the carbon atoms 101 adjacent in the left-right direction shown in FIG. Cs or B that brings low resistance as an atom (may be a molecular layer)
By inserting a, the intercalation is applied to increase the efficiency of electron emission and to form the in-plane selective electron emission region, and the chemical stability of the carbon surface at the time of emitting the emitted electrons 103 and It is intended to form a cold cathode that achieves both a reduction in work function due to curation. However, the order of intercalation is the number of carbon atom layers formed of carbon atoms 101, that is, the number of carbon atom layers formed by one intercalation layer 102. It is known that the characteristics such as resistance can be controlled by controlling the order.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the drawings together with an embodiment (example) of the invention. In all the drawings for explaining the embodiments of the invention, components having the same function are designated by the same reference numeral, and the repeated description thereof will be omitted.

(Embodiment 1) FIG. 2 is a diagram for explaining a structure and a manufacturing method of a cold cathode device according to Embodiment 1 of the present invention. Hereinafter, Embodiment 1 will be described with reference to FIG. The structure and manufacturing method of the cold cathode device will be described. However, FIGS. 2A to 2C are cross-sectional views of the cold cathode device according to the first embodiment.

First, as shown in FIG. 2A, after depositing a photosensitive paste, for example, a cathode bus 202 on a glass substrate 201, which is a substrate, a column direction (vertical direction on the paper surface of FIG. 2) is formed by a lithography method or the like. ) Line. This cathode bus bar 202 is, as shown in FIG.
Five cathode buses 2 formed on the upper surface of the glass substrate 201
02 are independent.

Next, PSG (phosphosilicate glass) is used as a glass paste for photo-embedding having a thickness of several microns or less by a well-known reflow technique.
s) and the like are deposited to form a layer of the glass paste for photo embedding. After that, as shown in FIG. 2A, the cell region 210 is formed from the upper surface side to the depth at which the cathode bus bar 202 and the glass substrate 201 are exposed by a lithography method or the like with respect to the substrate manufactured by the steps described above. Form. In this way, first, the glass substrate 20
A cell structure separated by a barrier 203 is formed on the upper surface side of 1. In addition, the cathode bus bar 202 is provided on the upper surface side of the glass substrate 201.
The process of forming the cell structure and the cell structure is the same as the conventional one.

After that, the glass substrate 201 on which the cathode bus bar 202 and the cell structure are formed is subjected to chemical vapor deposition (C) using a hydrocarbon-based material such as CH ₄ or CO at a low temperature as a raw material.
VD: ChemicalI Vapor Deposit
Ion) and the like, diamond-like carbon 205 (DL
C: Diamond-Like Carbon) is deposited to form the DLC layer 204.

Next, as shown in FIG. 2B, the laser beam 206 is applied from the upper surface side of the deposited DLC layer 204.
Are scanned and irradiated to anneal the DLC layer 204 to graphitize the DLC to form a graphite layer 207 which is a carbon-based material layer. However, the DLC phase 20 produced by the chemical vapor deposition method using the above raw materials
No. 4 is usually graphitized by heating at a temperature of about 600 ° C. for about 10 minutes.
The graphite layer 207 is formed by selecting the wavelength, the beam power, and the irradiation time so as to bring about such a heating effect. The graphite layer (graphite film) 207 may be directly deposited on the cell region 210 by using other known methods such as arc discharge and laser ablation.

Next, as shown in FIG. 2 (c), impurities such as Cs and Ba which become intercalation atoms 208 are introduced into the graphite layer (graphite film) 207 by well-known ion implantation or thermal diffusion method. Etc. and add intercalation. As a result of this intercalation, as shown in FIG.
An intercalation layer 209 in which impurities such as Cs and Ba are introduced (intercalated) is formed between the layers of the graphite layered crystal of 1. That is, the cold cathode device of the first embodiment has a structure in which Cs, Ba, and the like, which are impurities having a work function smaller than that of graphite, are introduced (intercalated) between the layers of the graphite layered crystal, so that carbon in electron emission is generated. The structure makes it possible to obtain highly efficient and selective electron emission characteristics while making the most of the chemical stability of.

In the above-mentioned method, 1) DLC can be deposited at a temperature of room temperature to 300 ° C., 2) laser annealing is heating only on the surface, and 3) intercalation of Cs, Ba and the like is low. It is possible to obtain the effect that the whole process such as possible can be performed at a low temperature. As a result, an inexpensive glass or plastic substrate can be used without using an expensive crystal glass or the like having excellent heat resistance for the glass substrate 201, and as described later, the cold cathode device according to the first embodiment. When is used as a display device, the weight can be reduced.

On the other hand, the cold cathode device according to the first embodiment is arranged in a vacuum airtight container, and an electrode serving as an anode is arranged in a position facing the cold cathode device in this vacuum airtight container to form a two-pole structure. By disposing a well-known phosphor on the cold cathode device side of the anode, it is possible to form a fluorescent light emission type display device for displaying characters, graphics and the like. Therefore, by supplying a driving signal of a predetermined voltage between the cathode bus bar 202 and the anode, the phosphor is caused to emit light by the electrons emitted from the intercalation layer 209 of the cold cathode device, so that the formation pattern of each electrode and the driving signal are changed. It is possible to perform light emission display of corresponding characters or graphics or light emission display as a light emitting element. At this time, in the cold cathode device of the first embodiment, it is possible to obtain a highly efficient and selective electron emission characteristic while utilizing the chemical stability of carbon in the electron emission from the intercalation layer 209.
Even with a large-area display device, it is possible to obtain a highly efficient and high-quality light-emitting display in which display unevenness is significantly reduced.

(Embodiment 2) FIG. 3 is a diagram for explaining a structure and a manufacturing method of a cold cathode device according to Embodiment 2 of the present invention. Hereinafter, an embodiment will be described based on FIG. The structure and manufacturing method of the cold cathode device 2 will be described. However, the cold cathode device of the second embodiment shown in FIG. 3 is an example of fabrication on a glass substrate having no cell structure or cell barrier in order to form a high density cold cathode array.

First, as shown in FIG. 3A, a cathode bus 302 made of a refractory metal or the like is formed on a glass substrate 301. At this time, as will be described later, this cathode bus 3
02 is deposited on the upper surface of 02, and this DLC is further heated to be graphitized. Therefore, the material of the cathode bus bar 302 is stable to these heat treatments, for example, tantalum,
A refractory metal such as molybdenum or tungsten is desirable.

Next, as shown in FIG. 3B, D is formed on the upper surface side of the glass substrate 301 on which the cathode bus bar 302 is formed, that is, on the side of the glass substrate 301 on which the cathode bus bar 302 is formed.
The LC layer 303 is formed. However, this DLC layer 303
For example, similar to the first embodiment, the glass substrate 301 on which the cathode bus bar 302 is formed is diamond-shaped by a chemical vapor deposition method using a hydrocarbon-based material such as CH ₄ or CO as a raw material at a low temperature. Carbon 304 (DLC: Diam
ond-like carbon).

Next, as shown in FIG. 3C, the energy beam such as the laser beam 305 is narrowed down and the cathode bus 3
The irradiation region 308 is annealed by irradiating the laser beam 305 only on the region to be the electron emission region on 02. By this annealing treatment, only the DLC layer 303 in the irradiation region 308 of the laser beam 305 is locally graphitized to form a graphite region, that is, a graphite layer 306. At this time, the graphite layer 306 serving as the electron emission region is substantially determined by the beam diameter of the laser light 305 to be irradiated. Therefore, laser light 3
By repeating the movement and irradiation of the irradiation region 308 of 05, it becomes possible to easily form the array of the graphite layer 306 which becomes the electron emission region.

Next, as shown in FIG. 3D, with respect to the irradiation region (graphite layer 306) of the laser beam 305, Cs and interstitial atoms 307 are used as the intercalation atoms 307 as in the first embodiment. An intercalation layer 309 is formed by adding impurities such as Ba by ion implantation or a thermal diffusion method and performing intercalation. However, the intercalation atoms Ca and Ba penetrate between the graphite layers to form the intercalation layer, while D, which is in an almost amorphous state,
Since the intercalation layer is not formed in the LC layer 303, the intercalation layer can be selectively formed only in the graphitized region.

That is, the cold cathode device according to the second embodiment is
Cs, Ba, etc., which are impurities with a small work function, are introduced between the layers of the graphite layered crystal (intercalation).
As a result, the structure is such that it is possible to obtain highly efficient and selective electron emission characteristics while taking advantage of the chemical stability of carbon in electron emission. At this time, the intercalation layer 309 controls the irradiation of the laser light 305 and C
Since it can be formed by controlling the addition of impurities such as s and Ba, a high-density cold cathode array structure can be formed. As a result, when the cold cathode device of the second embodiment is used as the display device, a display device having high display resolution and high definition can be manufactured.

However, when the cold cathode device of the second embodiment is used as a display device, as in the first embodiment, it has a two-pole structure in which an anode is arranged so as to face the cold cathode device of the second embodiment. Emit electrons.

(Embodiment 3) FIG. 4 is a diagram for explaining the structure and manufacturing method of a cold cathode device according to Embodiment 3 of the present invention. The embodiment will be described below with reference to FIG. The structure and manufacturing method of the cold cathode device of No. 3 will be described. However, FIGS. 4A and 4C are plan views of the cold cathode device according to the third embodiment, and FIG. 4B is a line AA ′ shown in FIG. 4D is a sectional view taken along line CC ′ shown in FIG. 4C. First, the DLC layer 402 is uniformly formed on the upper surface side of the glass substrate 401. To do. However, this DLC layer 402 is, for example, similar to that of the second embodiment, the CH at a low temperature with respect to the glass substrate 401.
Diamond-like carbon (DLC: Diam) by a chemical vapor deposition method using hydrocarbons such as ₄ and CO as raw materials.
ond-like carbon).

Next, as shown in FIG. 4 (a), an energy beam such as a laser beam is narrowed down and the laser beam is moved in the lateral direction of the glass substrate 401.
Anneal the DLC layer 402 to a predetermined width. At this time,
By sequentially moving the region to be annealed downward (upward) and performing it a plurality of times, as shown in FIG. 4A, the graphite layer 40 formed by the annealing treatment is performed.
3 and the DLC layer 4 which is a region not annealed
02 and 10 are alternately arranged in a linear shape. However, as shown in FIG. 4B, the upper surface of the glass substrate 401 is heated by annealing so that the lower surface side of the DLC layer 402, that is, the side where the DLC layer 402 and the glass substrate 401 are in contact with each other. Graphite layer 403 on the side
To form. Further, in the cold cathode device of the third embodiment, graphite layer 403 becomes a region corresponding to the cathode bus.

Next, impurities such as Cs and Ba are added to the graphite layer 403 by ion implantation, thermal diffusion method or the like, and intercalation is performed, so that a part or the whole of the graphite layer 403 is not shown. To form an optional layer. Since this intercalation layer originally has a low resistance characteristic, it can be used as it is as a cathode bus.

Next, as shown in FIGS. 4C and 4D, an insulating film 405 is formed on the upper surface side of the graphite layer 403 and the intercalation layer, for example, by a well-known reflow technique to have a thickness of several microns or less. PSG (phosphosi
Licate glass) is deposited, and this glass paste for photo embedding is used as an insulating layer (insulating film) 405.

Next, as shown in FIG. 4C, the DLC layer 402 and the graphite layer 40 are formed on the upper surface side of the insulating film.
A gate electrode bus bar 404 extending in a direction not parallel to 3 (for example, an orthogonal direction) is formed. However, the third embodiment
The gate electrode bus bar 404 of 5 lines corresponds to 5 lines in which the direction orthogonal to the DLC layer 402 and the graphite layer 403 is the extending direction. At this time, the intercalation layer and each gate electrode bus 404 are separated by a thickness of several microns or less, that is, a thick insulating film.

After this, as shown in FIGS. 4C and 4D, with respect to the substrate manufactured by the steps described above,
An electron emission hole 406 as an electron emission region is formed from the gate electrode bus 404 side to a depth at which the intercalation layer is exposed by a lithography method or the like. At this time, for example, as shown in FIG. 4D, one electron emission hole 406 is formed in each of the regions where the intercalation layer and the gate electrode bus 404 intersect with each other with the insulating film 405 interposed therebetween. However, it is needless to say that the number of electron emission holes 406 in this intersection region may be two or more.

In the thus-formed cold cathode device of the third embodiment, an electric field is applied between the gate electrode bus 404 and the intercalation layer to emit electrons.

Even in this case, the cold cathode device of the third embodiment has a structure in which Cs, Ba, etc., which are impurities having a small work function, are introduced (intercalated) between the layers of the graphite layered crystal. In addition, it becomes a structure capable of obtaining highly efficient and selective electron emission characteristics while making the most of the chemical stability of carbon in electron emission.

On the other hand, the cold cathode device according to the third embodiment is placed in a vacuum airtight container, and an electrode serving as an anode is placed at a position facing the cold cathode device in this vacuum airtight container,
By disposing a well-known phosphor on the cold cathode device side of the anode electrode, it is possible to form a fluorescent light emission type display device for displaying characters, graphics and the like. Therefore, by supplying a driving signal of a predetermined voltage between the graphite layer 403 serving as the cathode bus bar, the gate electrode bus bar 404, and the anode electrode, the phosphor emits light by the electrons emitted from the not-shown intercalation layer of the cold cathode device. However, it is possible to perform light emission display of characters and graphics or light emission display as a light emitting element according to the formation pattern of each electrode and the drive signal. At this time, in the cold cathode device of the third embodiment, it is possible to obtain a highly efficient and selective electron emission characteristic while making the most of the chemical stability of carbon in the electron emission from the intercalation layer.
Even with a large-area display device, it is possible to obtain a highly efficient and high-quality light-emitting display in which display unevenness is significantly reduced.

In the first to third embodiments, impurities are used as impurities.
I explained the case of using Cs and Ba.
Without limitation, K (potassium), Rb (rubidi
From graphite such as um) and Sr (strontium)
It is also possible to use an alkali metal with a low work function
Needless to say. Furthermore, U, I_Two, Br_Two, Cl _Two
It goes without saying that a metal such as may be used.

In the first to third embodiments, the case where the field emission cold cathodes of the cold cathode device are arranged in an array to form the display device has been described, but the cold cathode device and the photoelectric conversion film are opposed to each other. It goes without saying that the image pickup device can be configured by arranging them. Particularly, in the second embodiment,
Since a high-density cold cathode array structure can be formed, a high-definition imaging device can be manufactured.

Further, in the first to third embodiments, the stage (order) for introducing the impurities is not particularly limited, but the electrons emitted from the field emission cold cathode are combined by combining the stages for introducing the impurities. It goes without saying that the configuration may be controlled.

The inventions made by the present inventors are as follows.
Although the specific description has been given based on the embodiment of the invention, the invention is not limited to the embodiment of the invention and can be variously modified without departing from the scope of the invention. .

[0052]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

(1) A stable and highly efficient cold cathode or its array can be manufactured at a low temperature.

(2) By narrowing the energy beam of a laser or the like, it is possible to form an electron emission region and an array thereof having a size corresponding to the beam size. Therefore, a display device combined with a phosphor or a photoelectric conversion film is formed. Higher definition of the image sensor combined with

(3) Since the cathode bus bar can also be formed of the same host material, there is an effect that the structure and process of the cold cathode array can be simplified.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the principle of the structure of a cold cathode device according to the present invention.

FIG. 2 is a diagram for explaining the structure and the manufacturing method of the cold cathode device according to the first embodiment of the present invention.

FIG. 3 is a diagram for explaining the structure and manufacturing method of the cold cathode device according to the second embodiment of the present invention.

FIG. 4 is a diagram for explaining a structure and a manufacturing method of a cold cathode device according to a third embodiment of the present invention.

[Explanation of symbols]

101 ... Carbon atom 102 ... Intercalation atom 103 ... Emitted electron 201 ... Glass substrate 202 ... Cathode bus bar 203 ... Barrier 204 ... DLC
Layer 205 ... Diamond carbon 206 ... Laser beam 207 ... Graphite layer 208 ... Intercalation atom 209 ... Intercalation layer 210 ... Cell region 301 ... Glass substrate 302 ... Cathode bus 303 ... DLC layer 304 ... Diamond carbon 305 ... Laser Light 306 ... Graphite layer 307 ... Intercalation atom 308 ... Laser light irradiation region 309 ... Intercalation layer 401 ... Glass substrate 402 ... DLC
Layer 403 ... Graphite layer 404 ... Gate electrode bus 405 ... Insulating film 406 ... Electron emission hole

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Toshihiro Yamamoto             1-10-11 Kinuta, Setagaya-ku, Tokyo, Japan             Broadcasting Association Broadcast Technology Institute (72) Inventor Satoshi Ueda             1-10-11 Kinuta, Setagaya-ku, Tokyo, Japan             Broadcasting Association Broadcast Technology Institute (72) Inventor Tatsuya Takei             1-10-11 Kinuta, Setagaya-ku, Tokyo, Japan             Broadcasting Association Broadcast Technology Institute (72) Inventor Kei Hagiwara             1-10-11 Kinuta, Setagaya-ku, Tokyo, Japan             Broadcasting Association Broadcast Technology Institute F-term (reference) 5C031 DD17 DD19                 5C036 EG12 EH11

Claims (9)

[Claims] 1. A method for producing a cold cathode device, comprising: a cathode bus bar formed on a substrate; and a field emission cold cathode made of a carbon-based material electrically connected to the cathode bus bar. Forming a cathode busbar; forming a carbon-based material layer containing graphite as a main component material and electrically connected to the cathode busbar; and adding an impurity atom or molecule having a work function smaller than that of graphite to the carbon-based carbon And a step of forming a field emission cold cathode by introducing the material into a material layer. 2. The cold cathode device according to claim 1, wherein the impurity atom or molecule is introduced between plate crystals of graphite forming the carbon-based material layer. Method for manufacturing device. 3. The cold cathode device manufacturing method according to claim 1, wherein an alkali metal having a work function smaller than that of the graphite is introduced as the impurity atoms or molecules. Manufacturing method. 4. The method for manufacturing a cold cathode device according to claim 3, wherein an alkali metal having a work function smaller than that of the graphite is introduced as the impurity atoms or molecules. . 5. The method of manufacturing a cold cathode device according to claim 4, wherein the alkali metal is K, Rb, Cs,
A method of manufacturing a cold cathode device, comprising introducing one of Ba and Sr metals. 6. The method of manufacturing a cold cathode device according to claim 1, wherein any one of U, I ₂ , Br ₂ and Cl ₂ is introduced as the impurity atom or molecule. A method for manufacturing a characteristic cold cathode device. 7. A cold cathode device having a cathode bus bar formed on a substrate and a field emission cold cathode made of a carbon material electrically connected to the cathode bus bar, wherein the cold cathode device is electrically connected to the cathode bus bar. As described above, a carbon-based material layer made of a carbon-based material is formed, and regions where impurity atoms or molecules are introduced are formed between the plate-like crystals of the carbon-based material layer, and the impurity-introduced region is an electric field. A cold cathode device, characterized in that it forms an emission cold cathode. 8. The cold cathode device according to claim 7,
A cold cathode device, wherein a plurality of the field emission regions are formed in a surface of the carbon-based material layer. 9. A cold cathode device in which a plurality of field emission cold cathodes are formed and a phosphor anode are opposed to each other, and a voltage applied between the field emission cold cathode and the phosphor anode is controlled, In a display device for displaying an image according to an image signal, the cold cathode device is formed with a carbon-based material layer made of a carbon-based material so as to be electrically connected to a cathode bus formed on a substrate. A display device, wherein a plurality of regions in which impurity atoms or molecules are introduced are formed between the plate-like crystals of the carbon-based material layer, and the impurity-introduced regions form a field emission cold cathode.