JP2003203554A - Electron-emitting device - Google Patents

Abstract

(57) [Problem] To provide an electron-emitting device having a uniform lifetime of electrons emitted from an electron-emitting portion, converging electrons on a light-emitting surface, and having a long lifetime. SOLUTION: A cathode electrode 2 is arranged in a line on a substrate 1, and a linear gate electrode 4 is arranged so as to intersect with the cathode electrode 2 via an insulating layer 3, and intersects with the cathode electrode 2. Two fine holes a and b arranged on the gate electrode 4 along the wiring direction of the gate electrode 4 and opened to the cathode electrode, and an electron emission portion arranged on the cathode electrode 2 in the fine hole 5. An electron-emitting device wherein the center of 5 is arranged between the center between the side walls of adjacent fine holes a and b and the center of said fine holes.

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 of various electron beam utilizing devices such as a display device, various sensors, an electron microscope, and an electron beam exposure device.

[0002]

2. Description of the Related Art A conventional cold cathode electron-emitting device will be described with reference to the schematic sectional view of FIG. A plurality of striped cathode electrodes 2 and an insulating layer 3 are formed on the surface of a substrate 1 such as glass.
And a plurality of stripe-shaped gate electrodes 4 are formed. The cathode electrodes 2 and the gate electrodes 4 are usually arranged so as to be orthogonal to each other and form a matrix. Each cathode electrode 2 and gate electrode 4 is connected to the control means 6, and a drive voltage is selectively applied. The orthogonal region of each cathode electrode 2 and gate electrode 4 corresponds to one pixel of the display device. Figure 1
It is a schematic sectional drawing of a pixel part.

In a region where the cathode electrode 2 and the gate electrode 4 are orthogonal to each other, a plurality of fine openings are formed penetrating the gate electrode 4 and the insulating layer 3. A conical microchip 7 is formed in this opening and is electrically integrated with the cathode electrode 2. Microchip 7
Is made of a refractory metal such as W or Mo, and its tip is located substantially on the same plane as the gate electrode 4.

When a predetermined voltage is applied to the cathode electrode 2 and the gate electrode 4 from the control means 6, electrons are emitted from the tips of the microchips 7 by the tunnel effect.

When the electron-emitting device of FIG. 10 is applied to a display device, the electron-emitting device is combined with the gate electrode 4 and a transparent panel substrate (not shown) provided at a predetermined distance. On the panel substrate, stripe-shaped anode electrodes arranged in the same direction as the cathodes, and fluorescent bodies are formed on the anode electrodes. The anode electrode is
It is made of a transparent conductive material such as ITO (Indium Tin Oxide), and its connection end is connected to the control means 6. The space between the substrate 1 and the panel substrate is a high vacuum region.

With such a configuration, the microchip 7
The electrons emitted from the tip are accelerated by the voltage applied between the cathode electrode 2 and the anode electrode, enter the fluorescent surface, and are converted into visible light. This visible light is observed through the transparent anode electrode and the panel substrate. In the case of a color display device, the anode electrode and the fluorescent surface are divided and arranged corresponding to each color of R, G and B.

However, the above-mentioned electron-emitting device shown in FIG. 10 has the following problems. First, the microchip 7
Is difficult to manufacture, especially at its tip. If the shape of the tip of the microchip 7 is different for each microchip 7, the amount of electrons emitted from each microchip 7, that is, the amount of current is non-uniform in each pixel, and this electron-emitting device is used in a display device. When used, the bright spots on the panel substrate also become non-uniform, degrading the image quality.

Secondly, the gas remaining in the operating vacuum is ionized and adheres to the microchip 7 or changes its surface, so that the microchip 7 is prone to deterioration over time and the amount of emitted electrons is reduced. I have a problem to do.

In order to avoid the above problems, an electron-emitting device using carbon nanotubes as an emitter is proposed in Japanese Patent Laid-Open No. 9-221309. A carbon nanotube is a hollow cylinder formed by rolling a graphene sheet in which carbon atoms are regularly arranged, and its outer diameter is on the order of nm, and its length is 0.5 μm to several tens of μm. is there. Further, since the carbon nanotube has a characteristic that it has high chemical and physical stability, it has a characteristic that it is hardly affected by adsorption of a residual gas in an operating vacuum, ion bombardment and the like. A schematic sectional view of this electron-emitting device is shown in FIG. The carbon nanotubes 8 are on the carbonaceous substrate 9 (the carbonaceous substrate 9 is shown in FIG.
Not in 1. Please correct Figure 11. ) Is irradiated with ions, and the cathode electrode 2, the insulating layer 3 and the electron beam extracting grid 10 are arranged so as to surround the carbon nanotube formation region.

[0010]

In an electron-emitting device having a structure similar to that of the electron-emitting device shown in FIG. 10, flight trajectories of electrons emitted from the carbon nanotubes when a voltage is applied between the carbon nanotubes and the grid. Is shown in FIG. As is apparent from FIG. 12, the electrons emitted from the carbon nanotubes 8 spread widely without converging. Therefore, when a display device is configured using this electron-emitting device, the electrons are separated from the grid 10 by a predetermined distance. It is necessary to increase the area of the fluorescent surface provided on the anode electrode. Therefore, a fine pixel cannot be formed, and a display device with high saturation cannot be formed.

The present invention is intended to solve such a problem of the prior art, focuses the emitted electrons, has a long life, and further has a plurality of electron-emitting devices. An object of the present invention is to provide an electron-emitting device in which the amount of emitted electrons emitted from each electron-emitting device, that is, the amount of current is uniform.

[0012]

In order to achieve the above object, the electron-emitting device of the present invention has a structure in which a cathode electrode arranged in a line on a substrate intersects with the cathode electrode via an insulating layer. A line-shaped gate electrode, two fine holes that are arranged side by side along the direction of the gate electrode on the gate electrode that intersects with the cathode electrode, and are opened to the cathode electrode; And an electron emitting portion arranged on the cathode electrode, and the center of the electron emitting portion is arranged between the center between the side walls of the adjacent fine holes and the center of the fine hole. Thus, by arranging the center of the electron emitting portion not to coincide with the center of the fine hole and positively arranging it on the side wall side of the adjacent fine hole, the electrons emitted from the electron emitting portion converge and reach the phosphor screen. To do.

Further, it is characterized in that carbon nanotubes are used in the electron emitting portion. A carbon nanotube is a hollow cylinder formed by rolling a graphene sheet in which carbon atoms are regularly arranged, and its outer diameter is on the order of nm, and its length is 0.5 μm to several tens of μm. is there. Also, carbon nanotubes
Since it has the characteristics of high chemical and physical stability,
It is not easily affected by adsorption of residual gas in operating vacuum and ion bombardment. Therefore, by using carbon nanotubes as the electron emitting portions, stable electron emission can be obtained, and an electron emitting device having a long life can be realized. Further, when there are a plurality of electron emitting devices, each electron emitting portion is The amount of electrons emitted from the can be made uniform.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention is a linear electrode arranged in a line on a substrate and a linear electrode arranged so as to intersect the cathode electrode via an insulating layer. Of the gate electrode, two fine holes arranged side by side along the wiring direction of the gate electrode on the gate electrode intersecting with the cathode electrode and opened to the cathode electrode, and arranged on the cathode electrode in the fine hole. And a center of the electron emitting portion is disposed between a center between side walls of adjacent fine holes and a center of the fine hole. This is an electron-emitting device, and the electrons emitted from the electron-emitting portion can be focused on the phosphor surface provided on the cathode electrode.

Further, the invention according to claim 2 of the present invention is
A cathode electrode arranged in a line on the substrate, a line-shaped gate electrode arranged so as to intersect with the cathode electrode through an insulating layer, and the cathode electrode on the gate electrode intersecting with the cathode electrode An electron-emitting device comprising two fine holes arranged side by side along the wiring direction of the above and opened to the cathode electrode, and an electron-emitting portion arranged at the cathode electrode in the fine holes, The electron-emitting device is characterized in that the center of the electron-emitting device is arranged between the center of the side walls of the adjacent fine holes and the center of the fine holes, and the electrons emitted from the electron-emitting portion are placed on the cathode electrode. It can be made to converge on the provided phosphor surface.

Further, the invention according to claim 3 of the present invention is
A cathode electrode arranged in a line on the substrate, a gate electrode arranged in a line so as to intersect the cathode electrode via an insulating layer, and the gate electrode on the gate electrode intersecting the cathode electrode An electron-emitting device comprising three or more fine holes arranged side by side in the wiring direction and opened to the cathode electrode, and an electron-emitting portion arranged in the cathode electrode in the fine holes, at least at both ends. The electron-emitting device is characterized in that the center of the electron-emitting portion of the fine hole is arranged between the center of the side walls of the adjacent fine holes and the center of the fine hole. The generated electrons can be focused on the phosphor surface provided on the cathode electrode.

The invention according to claim 4 of the present invention is
A cathode electrode arranged in a line on the substrate, a line-shaped gate electrode arranged so as to intersect the cathode electrode through an insulating layer, and a gate electrode intersecting the cathode electrode. An electron-emitting device comprising three or more fine holes arranged side by side in the wiring direction of the cathode electrode and opened to the cathode electrode, and an electron-emitting portion arranged in the cathode electrode in the fine hole. , At least the centers of the electron emitting portions of the fine holes are disposed between the centers of the side walls of the adjacent fine holes and the centers of the fine holes. The generated electrons can be focused on the phosphor surface provided on the cathode electrode.

Further, the invention according to claim 5 of the present invention is
A cathode electrode arranged in a line on the substrate, a line-shaped gate electrode arranged so as to intersect the cathode electrode through an insulating layer, and a matrix formed on the gate electrode intersecting the cathode electrode. An electron-emitting device comprising a plurality of fine holes arranged and opened to the cathode electrode, and an electron-emitting portion arranged in the cathode electrode in the fine hole, wherein the center of the electron-emitting portion of the fine hole is the fine hole. An electron-emitting device characterized by being arranged between the center of a hole and the center of the matrix, wherein electrons emitted from an electron-emitting portion can be converged on a phosphor surface provided on a cathode electrode. .

Further, the invention according to claim 6 of the present invention is
6. The electron emitting device according to claim 1, wherein the electron emitting portion is formed of a carbon tube, and the electrons emitted from the electron emitting portion are evenly distributed on a phosphor surface provided on the cathode electrode. Can be converged.

Next, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1) An electron-emitting device according to claims 1, 3 and 6 of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of an electron-emitting device of the present invention,
FIG. 2 is a plan view of the electron-emitting device, and FIG. 3 is a perspective view of the electron-emitting device cut along the broken line connecting XX ′ shown in FIG.

First, a method of manufacturing the electron-emitting device shown in FIGS. 1 to 3 will be described.

On the substrate 1 such as glass, Al, Nb, Mo, W,
Or metal such as Cr is deposited, sputtered or CV
200 nm by D (Chemical Vapor Deposition) method
It is formed to a thickness of about the same. After that, a resist film is applied and formed, and a predetermined line-shaped resist mask is formed by exposure and development. Using this resist mask as an etching mask, the metal film is patterned by RIE (Reactive Ion Etching) to obtain the cathode electrode 2. By using, for example, a mixed gas of Cl2 and O2 as the etching gas, the etching selection ratio with the underlying substrate 1 can be secured.

Next, after removing the resist mask, the electron emitting portion 5 having a fine projection structure is formed at a predetermined position on the cathode electrode 2. The electron emitting portion 5 is, for example, a carbon nanotube, and can be formed by dispersing the carbon nanotube in a conductive paste, arranging the carbon nanotube at a predetermined position by a screen printing method, and then performing a baking process.

After that, as the insulating layer 3, SiO2, or
1μ by SiN vapor deposition, sputtering or CVD method
It is formed to a thickness of about m.

Further, a metal such as Al, Nb, Mo, W or Cr is vapor-deposited, sputtered or CVD on the insulating layer 4.
Then, a line-shaped gate electrode 4 orthogonal to the cathode electrode 2 is obtained by forming the gate electrode 4 in a thickness of about 100 nm by a method or the like and patterning the same as the cathode electrode 2.

After removing the resist mask, a new resist film is applied and formed, and a resist mask having an opening pattern is formed in the region where the cathode electrode 2 and the gate electrode 4 intersect. Using this as an etching mask, the gate electrode 4,
The insulating layer 3 is etched by RIE to form fine holes a and b.
And the electron-emitting portion 5 is exposed to complete the electron-emitting device. Alternatively, when the gate electrode 4 is formed,
An opening pattern may also be formed in the gate electrode 4 at the same time, and the insulating layer 3 may be etched by RIE using this as a mask.

In the electron-emitting device of the present invention produced as described above, two fine holes a and b are arranged in the pattern direction of the gate electrode 4 on the region where the gate electrode 4 and the cathode electrode 2 intersect. The electron-emitting portion 5 that is arranged and has a fine protrusion structure is arranged in the extending direction of the gate electrode 4.
It is arranged closer to the center of the region where the cathode electrode 2 and the gate electrode 4 intersect with each other than the center of the fine hole. That is, in FIG. 2, the electron emitting portion 5 in the fine hole a is arranged closer to the center X0 of the region where the cathode electrode 2 and the gate electrode 4 intersect with each other than the center X1 of the fine hole a in the X direction. Similarly, the electron emitting portion 5 in the fine hole b is arranged closer to the X0 side than the center X2 of the fine hole b in the X direction. Therefore, in FIG. 1, the distance from the electron emitting portion 5 to the position B of the gate electrode is shorter than the distance from the electron emitting portion 5 in the fine hole a to the position A of the gate electrode 4, and , The position C of the gate electrode 4 from the electron emitting portion 5 in comparison with the distance from the electron emitting portion 5 in the fine hole b to the position D of the gate electrode 4.
The distance to is shorter.

In the electron-emitting device having the electron-emitting portion 5 arranged at the above position, the electron-emitting portion 5 emits light when a voltage is applied between the electron-emitting portion 5 on the cathode electrode 2 and the gate electrode 4. The flight trajectory of electrons is shown in FIG. Since the electrons emitted from the electron emitting portion 5 are focused on the center of the area where the cathode electrode 2 and the gate electrode 4 intersect, a display device having a small fluorescent screen area can be produced.

Further, like the electron-emitting device shown in FIG.
When three or more fine holes are arranged side by side in the extension direction of the gate electrode 4, at least the two outermost ones in the extension direction of the gate electrode 4, that is, the fine holes c and d in FIG. If the electron emitting portion 5 is arranged closer to the center side of the region where the cathode electrode 2 and the gate electrode 4 intersect with each other than the center of the fine hole in the extending direction of the gate electrode 4, as described above, the electron emitting portion 5 is formed. There is an effect that the electrons emitted from the electron beam 5 are focused on the upper center of the region where the cathode electrode 2 and the gate electrode 4 intersect.

Further, the electron emitting portion 5 having the fine protrusion structure of the electron emitting device of the present invention is composed of carbon nanotubes. A carbon nanotube is a hollow cylinder formed by rolling a graphene sheet in which carbon atoms are regularly arranged, and its outer diameter is on the order of nm and its length is 0.5 μm.
It is a fine substance with an extremely high aspect ratio of several tens of μm. Further, since the carbon nanotube has a characteristic of high chemical and physical stability, it is hardly affected by adsorption of residual gas in an operating vacuum, ion bombardment and the like. Therefore, by using carbon nanotubes as the electron emitting portions, stable electron emission can be obtained, and an electron emitting device having a long life can be realized. Further, when there are a plurality of electron emitting devices, each electron emitting portion is The amount of electrons emitted from the can be made uniform.

(Embodiment 2) Next, claim 2 of the present invention,
4 and the electron-emitting device according to claim 6 will be described with reference to the drawings.

FIG. 6 is a plan view of the electron-emitting device of the present invention. The method of manufacturing the electron-emitting device shown in FIG.

In the electron-emitting device of the present invention shown in FIG. 6, two fine holes are arranged side by side in the region where the cathode electrode 2 and the gate electrode 4 intersect, and the orientation thereof is along the pattern of the cathode electrode 4. ing. The electron emitting portion 5 having a fine protrusion structure is formed along the pattern of the cathode electrode 2 by
It is arranged closer to the midpoint of the line segment connecting the centers of adjacent fine holes than the center of the fine holes. Therefore, for the same reason as described in the first embodiment, when a predetermined voltage is applied between the cathode electrode 2 and the gate electrode 4, the electrons emitted from the electron emitting portion 5 are emitted from the cathode electrode 2 and the gate electrode 4.
Since the light is focused on the center of the intersecting region, it is possible to create a display device having a small fluorescent screen area.

Further, like the electron-emitting device shown in FIG.
When the gate electrode is divided into a plurality of lines and coupled at the ends thereof, the gap between the gate lines has the same effect as the fine hole of FIG. Considered as fine pores.

Further, like the electron-emitting device shown in FIG.
When three or more fine holes are arranged side by side in the extension direction of the cathode electrode 2, at least the two outermost ones in the extension direction of the cathode electrode 2, that is, the fine holes e in FIG.
If the electron emission portion 5 in the fine hole f is arranged closer to the center side of the region where the cathode electrode 2 and the gate electrode 4 intersect with respect to the extension direction of the cathode electrode 4 than the center of the fine hole, Due to the same effect as described in 1, there is an effect that the electrons emitted from the electron emitting portion 5 are focused on the upper center of the region where the cathode electrode 2 and the gate electrode 4 intersect.

Further, the electron emitting portion 5 having the fine protrusion structure of the electron emitting device of the present invention is composed of carbon nanotubes. Therefore, due to the characteristics of the carbon nanotubes described above, stable electron emission can be obtained, and a long-life electron-emitting device can be realized. Further, by providing a plurality of electron-emitting devices, the electron emission from each electron-emitting portion can be increased. The emission amount can be made uniform and a long-life electron-emitting device can be realized.

(Embodiment 3) Next, an electron-emitting device according to claims 5 and 6 of the present invention will be described with reference to the drawings.

FIG. 9 is a plan view of the electron-emitting device of the present invention. Since the method of manufacturing the electron-emitting device shown in FIG.

In the electron-emitting device of the present invention shown in FIG. 9, fine holes are arranged in a matrix in a region where the cathode electrode 2 and the gate electrode 4 intersect, and at least the outermost portion in the extending direction of the cathode electrode 2 is formed. The electron emitting portion 5 in the micropore is disposed closer to the center of the area where the cathode electrode 2 and the gate electrode 4 intersect with each other than the center of the micropore in the extension direction of the cathode electrode 2, and the extension of the gate electrode 4 is The electron emission portion 5 in the outermost micropore in the direction is arranged closer to the center of the region where the cathode electrode 2 and the gate electrode 4 intersect with each other than the center of the micropore in the extension direction of the gate electrode 4.

By disposing the electron-emitting device 5 in such a position, when a predetermined voltage is applied between the cathode electrode 2 and the gate electrode 4 for the same reason as described in the first embodiment, the electron Since the electrons emitted from the emitting portion 5 are focused on the center of the region where the cathode electrode 2 and the gate electrode 4 intersect, a display device having a small fluorescent screen area can be produced.

Further, the electron emitting portion 5 having the fine protrusion structure of the electron emitting device of the present invention is composed of carbon nanotubes. Therefore, due to the characteristics of the carbon nanotubes described above, stable electron emission can be obtained, and a long-life electron-emitting device can be realized. Further, when there are a plurality of electron-emitting devices, the electrons from each electron-emitting portion are The release amount can be made uniform.

[0043]

As described above, the electron-emitting device of the present invention is capable of focusing emitted electrons, obtaining stable electron emission, and having a long life. In this case, the amount of electron emission from each electron-emitting device, that is, the amount of current can be made uniform.

[Brief description of drawings]

FIG. 1 is a sectional view of an electron-emitting device of the present invention.

FIG. 2 is a plan view of an electron-emitting device of the present invention.

FIG. 3 is a perspective view of an electron-emitting device of the present invention.

FIG. 4 is a diagram showing an electron flight trajectory of the electron-emitting device of the present invention.

FIG. 5 is a plan view of an electron-emitting device of the present invention.

FIG. 6 is a plan view of an electron-emitting device of the present invention.

FIG. 7 is a plan view of an electron-emitting device of the present invention.

FIG. 8 is a plan view of an electron-emitting device of the present invention.

FIG. 9 is a plan view of an electron-emitting device of the present invention.

FIG. 10 is a sectional view of a first conventional electron-emitting device.

FIG. 11 is a sectional view of a second conventional electron-emitting device.

FIG. 12 is a diagram showing an electron flight trajectory of a second conventional electron-emitting device.

[Explanation of symbols]

1 substrate 2 cathode electrode 3 insulating layers 4 gate electrode 5 Electron emission part 6 Control means 7 microchips 8 carbon nanotubes 9 Carbonaceous substrate 10 grid

Claims (6)

[Claims] 1. A cathode electrode arranged in a line on a substrate, a line-shaped gate electrode arranged so as to intersect with the cathode electrode via an insulating layer, and the gate electrode intersecting with the cathode electrode. An electron-emitting device comprising: two fine holes, which are arranged side by side along the wiring direction of the gate electrode and opened to the cathode electrode, and an electron-emitting portion arranged in the cathode electrode in the fine hole. The electron-emitting device is characterized in that the center of the electron-emitting portion is arranged between the center of the side walls of adjacent fine holes and the center of the fine holes. 2. A cathode electrode arranged in a line on a substrate, a line-shaped gate electrode arranged so as to intersect with the cathode electrode via an insulating layer, and the gate electrode intersecting with the cathode electrode. An electron-emitting device comprising: two fine holes, which are arranged side by side along the wiring direction of the cathode electrode and open to the cathode electrode; and an electron-emitting portion arranged in the cathode electrode in the fine hole. The electron-emitting device is characterized in that the center of the electron-emitting portion is arranged between the center of the side walls of adjacent fine holes and the center of the fine holes. 3. A cathode electrode arranged in a line on the substrate, a line-shaped gate electrode arranged so as to intersect the cathode electrode with an insulating layer interposed therebetween, and the gate electrode intersecting with the cathode electrode. An electron-emitting device comprising: three or more fine holes arranged side by side along the wiring direction of the gate electrode and opened to the cathode electrode; and an electron-emitting portion arranged in the cathode electrode in the fine hole. The electron-emitting device is characterized in that at least the centers of the electron-emitting portions of the micro holes at both ends are arranged between the centers of the side walls of the adjacent micro holes and the centers of the micro holes. 4. A cathode electrode arranged in a line on a substrate, a line-shaped gate electrode arranged so as to intersect with the cathode electrode via an insulating layer, and the gate electrode intersecting with the cathode electrode. An electron-emitting device comprising three or more fine holes arranged side by side along the wiring direction of the cathode electrode and opened to the cathode electrode, and an electron-emitting portion arranged in the cathode electrode in the fine holes. The electron-emitting device is characterized in that at least the centers of the electron-emitting portions of the micro holes at both ends are arranged between the centers of the side walls of the adjacent micro holes and the centers of the micro holes. 5. A cathode electrode arranged in a line on a substrate, a line-shaped gate electrode arranged so as to intersect with the cathode electrode via an insulating layer, and the gate electrode intersecting with the cathode electrode. An electron emitting device comprising a plurality of fine holes arranged in a matrix above and opening to the cathode electrode, and an electron emitting portion arranged in the cathode electrode in the fine holes, the electron emitting portion of the fine hole The electron-emitting device is characterized in that the center of is arranged between the center of the fine hole and the center of the matrix. 6. The electron emitting device according to claim 1, wherein the electron emitting portion is formed of a carbon tube.