KR101167182B1 - The field emission device - Google Patents

Abstract

The present invention relates to a field emission device, comprising: an anode substrate and a cathode substrate spaced apart from each other, a cathode electrode formed on the cathode substrate, a plurality of field emitters formed on the cathode electrode, and the A gate electrode formed between the cathode substrate and the anode substrate, the gate electrode including a plurality of opening groups, the opening group including an opening having a rectangular shape having a first side and a second side shorter than the first side. The direction of the first side of the opening group is arranged differently from the direction of the first side of the adjacent opening group. Therefore, by forming the rectangular opening, when the electron beam exiting the opening reaches the anode electrode, it can be spread in a specific direction to increase the filling ratio and consequently increase the field emission efficiency.

Field emitters, emitters, gate electrodes, openings, patterns

Description

Field emission device {THE FIELD EMISSION DEVICE}

The present invention relates to a field emission device. In particular, the present invention relates to field emission devices capable of controlling the spread of electron beams emitted from emitters.

The present invention is derived from the research conducted as part of the IT growth engine technology development project of the Ministry of Knowledge Economy and the Ministry of Information and Communication Research and Development. [Task management number: 2008-S-016-01, Task name: 15-inch dynamic surface backlight ].

Generally, field emission devices include a gate electrode that induces electron emission from a field emitter between the cathode and anode electrodes.

Openings are formed in the gate electrode such that electrons emitted from the field emitter escape and accelerate to the anode electrode.

In general, the opening formed in the gate electrode has a symmetrical shape such as a circle.

In general field emission devices, the larger the impact area of the electron beam reaching the anode electrode, the higher the efficiency.

In order to increase the efficiency, the density of the openings formed in the gate electrode should be increased.

However, increasing the density of the openings in the gate electrode of a constant area is structurally limited.

The technical problem to be achieved by the present invention is to provide a field emission device that can increase the efficiency by anisotropically spreading the electron beam exiting the opening by the effect of the anode electrode and the gate voltage by presenting a simple opening structure.

The field emission device according to the present invention comprises: an anode substrate and a cathode substrate spaced apart from each other; A cathode electrode formed on the cathode substrate; A plurality of field emitters spaced apart on the cathode electrode; And a gate electrode formed between the cathode substrate and the anode substrate, the gate electrode including a plurality of opening groups, wherein the opening group has a rectangular shape having a first side and a second side shorter than the first side. The direction of the first side of the opening group is arranged differently from the direction of the first side of the adjacent opening group.

Each of the opening groups may include one opening.

Each of the opening groups may include at least two openings.

The first direction of the opening group may be perpendicular to the first direction of the adjacent opening group.

The field emitter may be formed in alignment with the opening, and may have a size in which the shape of the opening is symmetrically reduced.

The field emitter is carbon nanotubes. It may be formed of one of carbon nanofibers and carbon-based synthetic materials.

According to the present invention, by forming the rectangular opening, when the electron beam exiting the opening reaches the anode electrode, it can be spread in a specific direction to increase the filling ratio and consequently increase the field emission efficiency.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding other components unless specifically stated otherwise.

Hereinafter, a field emission device according to the present invention will be described with reference to FIG. 1.

1 is a cross-sectional view showing a field emission device according to the present invention.

Referring to FIG. 1, the field emission device is formed of a cathode substrate 100 and an anode substrate 200 facing away from the cathode substrate 100.

The cathode electrode 110 is formed on the cathode substrate 100 toward the anode substrate 200, and the field emission emitter 120 is formed on the cathode electrode 110 by being spaced apart at regular intervals.

An anode electrode 210 is formed on the anode substrate 200 toward the cathode substrate 100, and a fluorescent film 220 is formed on the anode electrode 210.

In addition, a gate electrode 300 for inducing field emission of the field emission emitter 120 is formed within the separation distance between the cathode substrate 100 and the anode substrate 200.

The gate electrode 300 includes an opening 310 for passing electrons emitted from the field emission emitter 120, which opening 310 emits a field emission emitter 120 over the lower cathode substrate 100. ).

The gate electrode 300 may be made of a metal mesh.

 In the field emission device, the field emission emitter 120 emits electrons by the voltage applied to the gate electrode 300, and the emitted electrons pass through the opening 310 of the gate electrode 300 to the anode substrate 200. You are attracted to).

Electrons accelerated by the voltage applied to the anode electrode 210 collide with the fluorescent film 220 to generate cathode light emission. The electrons emitted from the field emission emitter 120 uniformly collide with the anode fluorescent film 220. It is necessary to design the discharge device.

In the case of the tripolar structure, as shown in FIG. 1, since electrons are not emitted in the region where the opening 310 is not formed, the ratio of the opening 310 to the total panel area is increased, or electrons passing through the opening 310 are opened. ) Should be designed to reach neighboring areas that are not formed.

FIG. 2 is a schematic view of a conventional gate electrode viewed from above, and FIG. 3 is a schematic view of a gate electrode viewed from above, according to an embodiment of the present invention.

Referring to FIG. 2, the opening 310 of the gate electrode 300 is formed in a circular shape, and a field emission emitter 120 having a size smaller than the diameter of the opening 310 is formed.

The circular opening 310 is symmetrically applied to an electric field in a first direction I and a second direction II perpendicular to the vertical direction based on the field emission emitter 120.

When the electric field is applied symmetrically in both perpendicular directions, the emitted electrons have the same spreading characteristics.

On the other hand, as shown in FIG. 3, when the opening 320 is formed in a rectangular shape, that is, when the length of the long side b and the short side a of the opening 320 is a rectangle of b> a, The electric field acts strongly in the second direction II perpendicular to the first direction compared to the first direction I, that is, in the direction of the short side a.

Therefore, the electrons emitted from the field emission emitter 120 have a characteristic of spreading further in the second direction II.

Also carbon nanotubes. When the nano emitter formed of one of the carbon nanofibers and the carbon-based synthetic material is used as the field emission emitter 120, a rectangular field emission emitter pattern may be formed as shown in FIG. 3 instead of a circular dot emitter. have.

In this case, since the emitter area is relatively larger than the circular dot pattern, the number of emitters 120 that contribute to the field emission can be increased to increase the field emission characteristics.

Hereinafter, a field emission device according to an embodiment of the present invention will be described using the pattern of FIG. 3 with reference to FIGS. 4 to 6.

4 and 5 are schematic views of the field emission device using the pattern of FIG. 3 as viewed from the top of the gate electrode, and FIGS. 6A to 6C illustrate an anode of the electron beam of the field emission device having the patterns of FIGS. 2, 4 and 5. The area reaching the electrode is shown.

Referring to FIG. 4, the gate electrode 300 includes a plurality of unit opening groups 350.

One unit opening group 350 includes a plurality of openings 320, and one opening 320 has a rectangular pattern as illustrated in FIG. 3.

In each unit opening group 350, the plurality of openings 320 are repeatedly arranged such that the long sides of the rectangles are placed in the vertical direction and the ones lying in the horizontal direction are adjacent to each other.

Therefore, the electron beam passing through the opening 320 spreads to a portion that the neighboring opening 320 cannot fill.

In this case, the field emission emitters 120 on the cathode electrode 110 may have a rectangular pattern and are aligned to be exposed by the openings 320.

In addition, as illustrated in FIG. 5, a plurality of unit opening groups 350 are formed in the gate electrode 300, and the number of the openings 320 in each unit opening group 350 may be twice that of FIG. 4.

That is, two openings 320 having the same long side direction of the rectangle form one opening pair 370, and pairs of openings having different directions of the long side of the rectangle are adjacent to each other.

 When arranged as shown in FIG. 5, the spreading characteristic of the electron beam may be further maximized, and in the same principle, the length and arrangement of the opening 320 may vary depending on the situation.

For example, the length of the long side of the opening 320 can be further increased, and the number of the openings 320 constituting the opening pair 370 can be formed in a number greater than two.

In the pattern of the gate electrode 300 of FIGS. 4 and 5, the unit opening group 350 is repeatedly formed.

FIG. 6A illustrates a circular opening of the gate electrode 300 as shown in FIG. 2, and FIG. 6B illustrates a rectangular shape of the opening 320 of the gate electrode 300, as illustrated in FIG. 4. The openings 320 of the 300 are rectangular, and the area A, B, and C respectively representing the electron beams reaching the anode electrodes 250, 260, 270 when the pair of openings have two openings 320 are shown. .

As shown in FIG. 6A, in the case of the circular opening 310, the electron beam exiting the opening 310 may spread in a circle when it reaches the anode electrode 250, and the electron beam may be interposed between the circular electron beam patterns. There may be areas that do not reach.

When the opening 320 has a rectangular opening 320 as shown in FIG. 6B and the openings 320 in different directions are arranged in the unit opening group, the electron beams exiting the opening 320 may be shortened. It is spread toward the sides, and the long sides are formed adjacent to each other in the vertical and horizontal direction, and the electron beams are spread to the arrival region of the electron beams through the neighboring openings 320.

 In addition, as shown in FIG. 6C, when the pair of rectangular openings 320 is provided, the overlapping area of the electron beams is greater than that in FIG. 6B, and the electron beams emitted from the neighboring openings 320 overlap each other. The filling ratio of the beam can be further increased.

In this case, the field emission emitter may have any shape and may be formed in a form in which the opening is reduced. When having a shape similar to the opening, the reduction ratio can be determined depending on the situation, and the opening and the emitter are aligned.

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 exemplary embodiments, It belongs to the scope of right.

1 is a cross-sectional view showing a field emission device according to the present invention.

2 is a schematic view of a conventional gate electrode viewed from above.

3 is a schematic view of the gate electrode according to the embodiment of the present invention viewed from above.

4 and 5 are schematic views of the field emission device using the pattern of FIG. 3 as viewed from the top of the gate electrode.

6A-6C show the area where the electron beam of the field emission device having the pattern of FIGS. 2, 4 and 5 reaches the anode electrode.

Claims (6)

An anode substrate and a cathode substrate spaced apart from each other; A cathode electrode formed on the cathode substrate; A plurality of field emitters spaced apart on the cathode and having a rectangular shape; And A gate electrode formed between the cathode substrate and the anode substrate and including a plurality of opening groups; / RTI > The opening group includes a plurality of first openings having a rectangular shape having a first side and a second side shorter than the first side, and the direction of the first side of the first opening is a first side of the adjacent first opening. A field emission device perpendicular to the direction of one side. delete The method of claim 1, The opening group further includes a plurality of second openings having the same shape and arrangement direction as the plurality of first openings, each of the second openings being adjacent to each of the corresponding first openings. . delete The method of claim 1, The field emitter is formed in alignment with the opening and has a size in which the shape of the opening is symmetrically reduced.  Field emission device. The method of claim 1, The field emitter is formed of one of carbon nanotubes, carbon nanofibers and carbon-based synthetic material.

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