KR101616509B1 - Field emission device and backlight unit having the same - Google Patents

Abstract

A field emission device and a backlight unit employing the field emission device are disclosed. The disclosed field emission device includes a plurality of conductive fibers provided on a cathode electrode and having a structure that is braided, and a fiber-type emitter including carbon nanotubes (CNTs) formed on the surfaces of the conductive fibers do.

Description

FIELD OF THE INVENTION The present invention relates to a field emission device and a backlight unit employing the field emission device,

There is provided a field emission device having a fiber-type emitter and a backlight unit employing the field emission device.

A field emission device is an element that emits electrons from an emitter by forming a strong electric field around the emitter formed on the cathode electrode. Such a field emission device can be applied to various kinds of systems using electron emission such as a backlight unit for a liquid crystal display device, a field emission display device, an X-ray tube, a microwave amplifier, a flat panel lamp,

A liquid crystal display device is an apparatus that displays an image on the front surface by transmitting light generated from a backlight unit disposed on the backside of a liquid crystal that controls light transmittance. Here, the backlight unit disposed on the rear surface may be a cold cathode fluorescent lamp (CCFL) type backlight unit, a light emitting diode (LED) type backlight unit, a field emission type backlight unit, or the like. The cold cathode fluorescent lamp type backlight unit has a disadvantage in that it is not easy to realize the large-sized screen and also it is impossible to perform screen division driving which can improve the picture quality by complementing the slow response speed of the liquid crystal. The screen division driving method is a method of independently driving only a region requiring light emission by dividing the light emitting surface of the backlight unit into a plurality of regions, thereby improving the energy efficiency of the backlight unit and improving the image quality of the liquid crystal display device . On the other hand, the light-emitting diode type backlight unit has a disadvantage in that it is expensive, though it is capable of screen division driving. The field emission type backlight unit emits light by impinging electrons emitted from the field emission device against a phosphor layer formed on the anode electrode. Such a field emission type backlight unit is advantageous in that it is easy to enlarge a screen area, can perform screen division driving, and is superior in price competitiveness compared to a light emitting diode type backlight unit.

In recent years, carbon nanotubes (CNTs) having excellent electron emission characteristics and excellent mechanical and chemical stability have been used as electron emission sources of field emission devices. As a method of forming a carbon nanotube emitter on a substrate, there is a method of forming a paste in which organic binder and carbon nanotube powder are mixed by a screen printing method at a desired position on a substrate, There is a method in which carbon nanotubes are directly grown on a substrate by using chemical vapor deposition (CVD).

The method using carbon nanotube paste can be continuous process and mass production by screen printing method, but it requires activation process after formation of carbon nanotube emitter. That is, after the carbon nanotube emitter is formed by the screen printing method, the carbon nanotubes are buried in the paste, so that the field emission characteristics are degraded. Accordingly, it is necessary to expose the carbon nanotubes to the outside of the paste through the activation process and align the exposed carbon nanotubes in the direction of the electric field. The activation process is generally a process of aligning the carbon nanotubes on the top of the carbon nanotube paste by exposing the carbon nanotubes to the outside using an adhesive tape or a tacky elastomer. However, such an activation process by the adhesive tape or the adhesive elastomer may damage the carbon nanotubes, and since organic materials remain in the emitter, the uniformity of the electron emission, the reliability of the emitter, and the lifetime may be deteriorated . The method of forming the carbon nanotube emitter by the chemical vapor deposition method first forms a catalyst at the position where the carbon nanotube grows, and then grows the carbon nanotube in the high temperature chemical vapor deposition apparatus. Therefore, this method has a disadvantage in that the material and size of the substrate can be restricted due to the high-temperature growth conditions and the size of the chemical vapor deposition chamber, and the production time is increased because the continuous process is difficult.

An embodiment of the present invention provides a field emission device having a fiber-type emitter and a backlight unit employing the field emission device.

According to an aspect of the present invention, there is provided a field emission device comprising:

Board;

A plurality of cathode electrodes formed on the substrate; And

And a fiber type emitter provided on the cathode electrode, the fiber type emitter including a plurality of conductive fibers having a structure that is braided and carbon nanotubes (CNTs) formed on the surfaces of the conductive fibers.

The conductive fibers may include at least one of metal fibers and carbon fibers.

The field emission device comprising: a first insulation layer formed on the substrate between the cathode electrodes; And a plurality of gate electrodes formed on the first insulating layer so as to intersect with the cathode electrodes. In this case, the twist pitch of the conductive fibers may be less than the spacing between the fibrous emitter and the gate electrode.

At least one through-hole may be formed in the gate electrode located on the fiber-type emitter.

A second insulating layer may be further formed between the gate electrode and the first insulating layer to cover the first insulating layer, the substrate, the cathode electrode, and the island-type emitter.

According to another aspect of the present invention, there is provided a field emission type backlight unit comprising:

A lower substrate and an upper substrate disposed opposite to each other at regular intervals;

A plurality of cathode electrodes formed on an upper surface of the lower substrate;

A fiber emitter provided on the cathode electrode and including a plurality of conductive fibers having a structure that is braided and carbon nanotubes formed on a surface of the conductive fibers;

An anode electrode formed on a lower surface of the upper substrate; And

And a phosphor layer formed on the anode electrode.

Here, the twist pitch of the conductive fibers may be smaller than the interval between the fibrous emitter and the anode electrode.

According to another aspect of the present invention, there is provided a field emission device comprising:

Board;

A plurality of trenches formed on the substrate;

A plurality of cathode electrodes formed on a bottom surface of the trenches; And

And a fiber type emitter provided on the cathode electrode, the fiber type emitter including a plurality of conductive fibers having a structure that is braided and carbon nanotubes (CNTs) formed on the surfaces of the conductive fibers.

According to another aspect of the present invention, there is provided a field emission type backlight unit comprising:

A lower substrate and an upper substrate disposed opposite to each other at regular intervals;

A plurality of trenches formed on the lower substrate;

A plurality of cathode electrodes formed on a bottom surface of the trenches;

A fiber emitter provided on the cathode electrode and including a plurality of conductive fibers having a structure that is braided and carbon nanotubes formed on a surface of the conductive fibers;

An anode electrode formed on a lower surface of the upper substrate; And

And a phosphor layer formed on the anode electrode.

According to the embodiment of the present invention, by using a plurality of conductive fibers and a fiber-type emitter composed of carbon nanotubes formed on the surfaces of the conductive fibers as an electron emitter, electron emission characteristics and reliability can be improved without a separate activation process have. In addition, since the conductive fibers have a twisted structure, it is possible to prevent a short circuit between the cathode electrode and the gate electrode or between the cathode electrode and the anode electrode, which may be caused by breakage of the emitter, .

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, like reference numerals refer to like elements, and the size and thickness of each element may be exaggerated for clarity of explanation.

1 is a partial perspective view of a field emission device according to an embodiment of the present invention and a field emission type backlight unit including the field emission device. Fig. 2 shows the fiber type emitter shown in Fig.

1, a field emission device according to an embodiment of the present invention includes a lower substrate 210, a plurality of cathode electrodes 215 formed on the lower substrate 210, A fiber-type emitter 220 provided on each upper surface, and a plurality of gate electrodes 230 for electron extraction. As the lower substrate 210, a glass substrate may be generally used, but the present invention is not limited thereto. A plurality of cathode electrodes 215 are formed on the lower substrate 210 at regular intervals. For example, the cathode electrodes 215 may be formed in a stripe shape. The cathode 215 may be formed of a transparent conductive material such as a metal or ITO (Indium Tin Oxide).

A fiber-type emitter 220 is provided on the upper surface of each of the cathode electrodes 215. The fiber type emitter 220 may be provided along the longitudinal direction of the cathode electrode 215. The fiber type emitter 220 includes a plurality of conductive fibers 221 and carbon nanotubes 222 formed on the surfaces of the conductive fibers 221. Here, the fiber type emitter 220 may have a structure in which a plurality of conductive fibers 221 are braided.

When the carbon nanotubes 222 are formed on the surface of the conductive fibers 221 or when the fiber emitters 220 are attached on the cathode electrodes 215 or when the fiber emitters 220, arcing occurs, a part of the conductive fibers 221 may be damaged and broken. In this case, if the conductive fibers 221 are not twisted, a part of the fiber-type emitter 220 may be short-circuited to the gate electrode 230 due to the cutting of the conductive fibers 221. However, if the conductive fibers 221 of the fiber-type emitter 220 are twisted together as in the present embodiment, even if a part of the conductive fibers 221 is broken by the damage, It is possible to prevent the gate electrode 220 from being short-circuited with the gate electrode 230. The twist pitch P of the conductive fibers 221 may be less than the distance d between the fiber emitter 220 and the gate electrode 230. [

In the present embodiment, the fiber emitters 220 may have a structure in which three or more conductive fibers 221 are twisted together to prevent the conductive fibers 221 that are twisted with each other from breaking. In FIG. 2, a fiber-type emitter 220 is illustrated by way of example in which three conductive fibers 221 are twisted together. However, the present embodiment is not limited to this, and various numbers of conductive fibers may have a structure in which they are twisted in various forms. In Fig. 3, another example of a fiber-type emitter that can be applied to this embodiment is illustrated by way of example. 3, reference numerals 220 ', 221', and 220 'denote fiber type emitters, conductive fibers and carbon nanotubes, respectively, and P denotes a twist pitch of the conductive fibers.

The conductive fibers 221 may include, for example, metal fibers or carbon fibers. In addition, when the conductive fibers 221 include carbon fibers, metal fibers may be further included to improve conductivity. In the present embodiment, it is preferable that the carbon fibers have a low thermal expansion coefficient in consideration of heat deformation generated when electrons are emitted. For example, the carbon fibers may have a coefficient of thermal expansion of about -1 to 5 x 10 < ^-6 > / K. However, the present invention is not limited thereto. Carbon nanotubes (CNTs) 222 having excellent electron emission characteristics are formed on the surface of the twisted conductive fibers 221. like this. When the carbon nanotubes 222 are formed on the surfaces of the conductive fibers 221 having a twisted structure, an electric field enhancing effect can be obtained. The carbon nanotubes 222 may be formed on the surfaces of the conductive fibers 221 by chemical vapor deposition (CVD) or resistance heating. The conductive fibers 221 having the carbon nanotubes 222 may be formed on the surfaces of the conductive fibers 221, The fiber type emitter 220 can be manufactured by twisting. The fiber type emitter 220 may be fabricated by first folding the conductive fibers 221 and then forming carbon nanotubes 222 on the surface of the twisted conductive fibers 221.

An insulating layer 212 is formed at a predetermined height on the upper surface of the lower substrate 210 between the cathode electrodes 215. The insulating layer 212 may be formed in a direction parallel to the cathode electrodes 215. On the upper surface of the insulating layer 212, a plurality of gate electrodes 230 for electron extraction are formed. The gate electrodes 230 may be formed to cross the cathode electrodes 215, and may be formed in a stripe shape, for example. At least one through hole 231 may be formed in the gate electrode 320 located above the fiber-type emitter 220. In the field emission device having the above structure, electrons are emitted from the fiber emitters 220 as a predetermined voltage is applied between the cathode electrodes 215 and the gate electrodes 230, Through the through holes 231 toward the anode electrode 245 described later.

The upper substrate 240 is disposed at a predetermined distance from the above-described field emission device. Specifically, the upper substrate 240 and the lower substrate 210 are opposed to each other with a predetermined gap therebetween. The upper substrate 240 is generally formed of a glass substrate as in the case of the lower substrate 210, but is not limited thereto. An anode electrode 245 is formed on the lower surface of the upper substrate 240. Here, the anode electrode 245 may be formed to cover the entire lower surface of the upper substrate 240, or may be formed in a stripe shape. The anode electrode 245 may be made of a transparent conductive material. A phosphor layer 246 is formed on the lower surface of the anode electrode 245.

When a predetermined voltage is applied to the cathode electrodes 215, the gate electrodes 230 and the anode electrodes 245 in the field emission type backlight unit having the above structure, the cathode electrodes 215 and the gate electrodes Electrons are emitted from the fiber-type emitters 220 by the voltage applied to the emitter 230. The electrons thus emitted are directed toward the anode electrode 245 through the through holes 231 formed in the gate electrodes 230 and then collide with the phosphor layer 246 to generate light.

As described above, in this embodiment, by using the fiber type emitter 220 composed of the conductive fibers 221 and the carbon nanotubes 222 formed on the surfaces of the conductive fibers 221 as an electron emission source, The electron emission characteristics and the reliability can be improved without the activation process of the electron emission device. The conductive fibers 221 have a mutually twisted structure to prevent a short circuit between the cathode electrode 215 and the gate electrode 230 that may be generated due to the breakage of the fiber type emitter 220, An electric field strengthening effect by the twisted structure can also be obtained.

4 is a partial perspective view of a field emission device and a field emission type backlight unit including the same according to another embodiment of the present invention. The field emission device shown in Fig. 4 is the same as the field emission device shown in Fig. 1 except that the lower substrate (210 in Fig. 1) and the insulating layer (212 in Fig. 1) are integrally formed in the field emission device shown in Fig. The same as the field emission device. Hereinafter, differences from the above-described embodiment will be mainly described.

Referring to FIG. 4, a plurality of trenches 211 are formed on a lower substrate 210 'to a predetermined depth. These trenches 211 may be formed parallel to each other at regular intervals. For example, the trenches 211 may be formed in a stripe shape. A cathode electrode 215 is formed on the bottom surface of each of the trenches 211 and a fiber emitter 220 is provided on the upper surface of each of the cathode electrodes 215. Here, the fiber type emitter includes conductive fibers of a braided structure and carbon nanotubes formed on the surfaces of the twisted conductive fibers as described above. The twist pitch P of the conductive fibers 221 may be less than the distance d between the fiber emitter 220 and the gate electrode 230. A plurality of gate electrodes 30 are formed on the upper surface of the lower substrate 10 'so as to intersect with the cathode electrodes 15. Here, the gate electrodes 15 may be formed in, for example, a stripe shape.

Although the field emission type backlight unit having a three-electrode structure including the cathode electrode 215, the gate electrode 230 and the anode electrode 245 has been described in the above embodiments, the present invention is not limited thereto. Field-emission type backlight unit having a two-electrode structure including a light-emitting layer. In this case, the twist pitch P of the conductive fibers 221 may be smaller than the interval between the fibrous emitter 220 and the anode electrode.

5 is a partial perspective view of a field emission device and a field emission type backlight unit including the same according to another embodiment of the present invention.

5, the field emission device according to another embodiment of the present invention includes a lower substrate 250, a plurality of cathode electrodes 255 formed on the lower substrate 250, and cathode electrodes 255 ), And a plurality of gate electrodes 270 for electron extraction. As the lower substrate 250, a glass substrate may be generally used, but the present invention is not limited thereto. A plurality of cathode electrodes 255 are formed on the lower substrate 250 at regular intervals. For example, the cathode electrodes 255 may be formed in a stripe shape. The cathode electrode 255 may be formed of a transparent conductive material such as a metal material or ITO (Indium Tin Oxide).

A fiber-type emitter 260 is provided on the upper surface of each of the cathode electrodes 255. The fiber-type emitter 260 may be provided along the longitudinal direction of the cathode electrode 55. The fiber type emitter 260 includes conductive fibers 261 having a twisted structure and carbon nanotubes 262 formed on the surfaces of the conductive fibers 261. In order to prevent the fiber type emitter 260 from being short-circuited to the gate electrode 270 due to the damage and breakage of a part of the conductive fibers 261, the twist pitch of the conductive fibers 261 is May be smaller than the distance between the fiber-type emitter 260 and the gate electrode 270. The fiber emitters 260 may have a structure in which three or more conductive fibers 261 are twisted to prevent the conductive fibers 261 twisted from being broken.

The conductive fibers 261 may include, for example, metal fibers or carbon fibers. In addition, when the conductive fibers 261 include carbon fibers, metal fibers may be further included to improve conductivity. Carbon nanotubes (CNTs) 262 having excellent electron emission characteristics are formed on the surface of the twisted conductive fibers 261.

A first insulating layer 252 is formed on the upper surface of the lower substrate 250 between the cathode electrodes 255 to a predetermined height. The first insulating layer 252 may be formed in a direction parallel to the cathode electrodes 255. On the first insulating layer 252, a second insulating layer 256 corresponding to the gate electrodes 270 described later is formed. Specifically, the second insulating layer 256 may be formed to intersect the cathode electrodes 255 between the gate electrodes 270 and the first insulating layer 252. The second insulating layer 256 may include a first insulating layer 252, a lower substrate 250, a cathode electrode 255, and a fiber emitter 260 located under the gate electrodes 270. [ As shown in FIG. A plurality of gate electrodes 270 for electron extraction are formed on the upper surface of the second insulating layer 256. Here, the gate electrodes 270 are formed along the upper surface of the second insulating layer 256. Accordingly, the gate electrodes 270 are formed to intersect with the cathode electrodes 255. When a predetermined voltage is applied between the cathode electrodes 255 and the gate electrodes 270 in the field emission device having the above structure, electrons are emitted from the fiber type emitters 260, Are directed to the anode electrode 285, which will be described later, through the space between the gate electrodes 270.

The upper substrate 280 is disposed at a predetermined distance from the above-described field emission device. Specifically, the upper substrate 280 is disposed opposite to the lower substrate 250 at regular intervals. The upper substrate 280 is generally formed of a glass substrate as in the case of the lower substrate 250, but is not limited thereto. An anode electrode 285 is formed on the lower surface of the upper substrate 280. The anode electrode 285 may be made of a transparent conductive material. A phosphor layer 286 is formed on the lower surface of the anode electrode 285.

When a predetermined voltage is applied to the cathode electrodes 255, the gate electrodes 270 and the anode electrodes 285 in the field emission type backlight unit having the above structure, the cathode electrodes 255 and the gate electrodes Electrons are emitted from the fiber-type emitters 260 by the voltage applied to the emitters 270. The electrons thus emitted are directed toward the anode electrode 285 through the gate electrodes 270 and then collide with the phosphor layer 286 to generate light.

6 is a partial perspective view of a field emission device and a field emission type backlight unit including the same according to another embodiment of the present invention. The field emission device shown in Fig. 6 is the same as the field emission device shown in Fig. 5 except that the lower substrate (250 in Fig. 5) and the insulating layer (252 in Fig. 5) are integrally formed in the field emission device shown in Fig. The same as the field emission device. Hereinafter, differences from the above-described embodiment will be mainly described.

Referring to FIG. 6, a plurality of trenches 251 are formed to a predetermined depth on a lower substrate 250 '. These trenches 251 may be formed parallel to each other at regular intervals. For example, the trenches 251 may be formed in a stripe shape. A cathode electrode 255 is formed on the bottom surface of each of the trenches 251 and a fiber emitter 260 is formed on the upper surface of each of the cathode electrodes 255. The fiber type emitter 260 includes the conductive fibers 261 having a twisted structure and the carbon nanotubes 262 formed on the surfaces of the conductive fibers 261 as described above. Here, the twist pitch of the conductive fibers 261 may be smaller than the interval between the fibrous emitters 260 and the gate electrode 270.

An insulating layer 256 corresponding to the gate electrodes 270 is formed on the lower substrate 250 '. Specifically, the insulating layer 256 may be formed to intersect the cathode electrodes 255 between the gate electrodes 270 and the lower substrate 250 '. The insulating layer 256 may be formed to cover the lower substrate 250 ', the cathode electrode 255, and the fiber emitter 260 located below the gate electrodes 270. A plurality of gate electrodes 270 for electron extraction are formed on the upper surface of the insulating layer 256. Here, the gate electrodes 270 are formed along the upper surface of the insulating layer 256. Accordingly, the gate electrodes 270 are formed to intersect with the cathode electrodes 255. The gate electrodes 270 may be formed in a stripe shape, for example.

Although the field emission type backlight unit having a three-electrode structure including the cathode electrode 255, the gate electrode 270, and the anode electrode 285 has been described in the above embodiments, the present invention is not limited thereto and the cathode electrode and the anode electrode A field emission type backlight unit having a two-electrode structure can be implemented. In this case, the twist pitch of the conductive fibers 261 may be smaller than the interval between the fibrous emitters 260 and the anode electrode. Although the field emission device including the fiber emitter has been exemplarily described in the field emission type backlight unit, the field emission device can be widely applied to other field applications such as a field emission display device, a lighting device, and the like have.

As described above, according to the embodiments of the present invention, a plurality of conductive fibers and a fiber-type emitter composed of carbon nanotubes formed on the surfaces of the conductive fibers are used as an electron emission source, And reliability can be improved. In addition, since there is no damage to the carbon nanotubes and no residual organic matter is present in the emitter, the lifetime of the emitter can be increased. In addition, since the conductive fibers have a twisted structure, it is possible to prevent a short circuit between the cathode electrode and the gate electrode or between the cathode electrode and the anode electrode, which may be caused by breakage of the emitter, .

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. Accordingly, the true scope of the present invention should be determined by the appended claims.

1 is a partial perspective view of a field emission device according to an embodiment of the present invention and a field emission type backlight unit including the field emission device.

Fig. 2 shows the fiber-type emitter shown in Fig.

Fig. 3 shows another example of the fiber type emitter shown in Fig.

4 is a partial perspective view of a field emission device and a field emission type backlight unit including the same according to another embodiment of the present invention.

5 is a partial perspective view of a field emission device and a field emission type backlight unit including the field emission device according to another embodiment of the present invention.

6 is a partial perspective view of a field emission device and a field emission type backlight unit including the field emission device according to another embodiment of the present invention.

Description of the Related Art

210, 210 ', 250, 250' ... Lower substrate 211, 251 .. Trench

212, 252, 256, ... insulating layers 215, 255,

220,260 ... fiber type emitter 221,261 ... conductive fiber

222,262 ... carbon nanotubes 230,270 ... gate electrode

231 ... through-hole 240, 280 ... upper substrate

245, 285, an anode electrode 246, 286,

Claims (27)

Board; A plurality of cathode electrodes formed on the substrate; A fiber type emitter provided on the cathode electrode and including a plurality of conductive fibers having a structure that is braided and carbon nanotubes (CNTs) formed on the surfaces of the conductive fibers; A first insulating layer formed on the substrate between the cathode electrodes; And And a plurality of gate electrodes formed on the first insulating layer so as to intersect with the cathode electrodes, Wherein a twist pitch of the conductive fibers is smaller than an interval between the fibrous emitter and the gate electrode. The method according to claim 1, Wherein the conductive fibers comprise at least one of metal fibers and carbon fibers. delete delete The method according to claim 1, Wherein at least one through hole is formed in the gate electrode located on the upper portion of the fiber type emitter. The method according to claim 1, And a second insulating layer formed between the gate electrode and the first insulating layer. The method according to claim 6, Wherein the second insulating layer is formed to cover the first insulating layer located below the gate electrode, the substrate, the cathode electrode, and the fibrous emitter. A lower substrate and an upper substrate disposed opposite to each other at regular intervals; A plurality of cathode electrodes formed on an upper surface of the lower substrate; A fiber emitter provided on the cathode electrode and including a plurality of conductive fibers having a structure that is braided and carbon nanotubes formed on a surface of the conductive fibers; An anode electrode formed on a lower surface of the upper substrate; A phosphor layer formed on the anode electrode; A first insulating layer formed on the upper surface of the lower substrate between the cathode electrodes; And And a plurality of gate electrodes formed on the first insulating layer so as to intersect with the cathode electrodes, Wherein a twist pitch of the conductive fibers is smaller than an interval between the fibrous emitter and the anode electrode. 9. The method of claim 8, Wherein the conductive fibers comprise at least one of metal fibers and carbon fibers. 9. The method of claim 8, Wherein a twist pitch of the conductive fibers is smaller than an interval between the fibrous emitter and the anode electrode. delete delete 9. The method of claim 8, Wherein at least one through-hole is formed in the gate electrode located on the upper portion of the fiber-type emitter. 9. The method of claim 8, And a second insulating layer formed between the gate electrode and the first insulating layer. Board; A plurality of trenches formed on the substrate; A plurality of cathode electrodes formed on a bottom surface of the trenches; A fiber type emitter provided on the cathode electrode and including a plurality of conductive fibers having a structure that is braided and carbon nanotubes (CNTs) formed on the surfaces of the conductive fibers; And And a plurality of gate electrodes formed on an upper surface of the substrate so as to cross the cathode electrodes, Wherein a twist pitch of the conductive fibers is smaller than an interval between the fibrous emitter and the gate electrode. 16. The method of claim 15, Wherein the conductive fibers comprise at least one of metal fibers and carbon fibers. delete delete 16. The method of claim 15, Wherein at least one through hole is formed in the gate electrode located on the upper portion of the fiber type emitter. 16. The method of claim 15, And an insulating layer formed between the gate electrode and the substrate. A lower substrate and an upper substrate disposed opposite to each other at regular intervals; A plurality of trenches formed on the lower substrate; A plurality of cathode electrodes formed on a bottom surface of the trenches; A fiber emitter provided on the cathode electrode and including a plurality of conductive fibers having a structure that is braided and carbon nanotubes formed on a surface of the conductive fibers; An anode electrode formed on a lower surface of the upper substrate; A phosphor layer formed on the anode electrode; And And a plurality of gate electrodes formed on the upper surface of the lower substrate so as to intersect with the cathode electrodes, Wherein a twist pitch of the conductive fibers is smaller than an interval between the fibrous emitter and the gate electrode. 22. The method of claim 21, Wherein the conductive fibers comprise at least one of metal fibers and carbon fibers. 22. The method of claim 21, Wherein a twist pitch of the conductive fibers is smaller than an interval between the fibrous emitter and the anode electrode. delete delete 22. The method of claim 21, Wherein at least one through-hole is formed in the gate electrode located on the upper portion of the fiber-type emitter. 22. The method of claim 21, Further comprising an insulating layer formed between the gate electrode and the substrate.

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