KR20070056680A - Electron emission display device - Google Patents

Abstract

An electron emission display device is provided to suppress arc discharge due to electron charging by forming an anti-electrification layer on a non-effective region and an inner wall of a sealing member. A first and second substrates(2,4) are disposed opposite to each other and include an effective region and a non-effective region. An electron emission unit(100) is provided on the effective region of the first substrate. A light emitting unit(110) is provided on the effective region of the second substrate. A sealing member(6) is arranged at edges of the first and second substrates in order to attach the first and second substrates to each other. An anti-electrification layer(12) is formed on the non-effective region of the first substrate, the non-effective region of the second substrate, and an inner wall of the sealing member.

Description

Electron Emission Display Device {ELECTRON EMISSION DISPLAY DEVICE}

1 is a cross-sectional view of an electron emission display device according to an embodiment of the present invention.

2 is a plan view of an electron emission display device according to an embodiment of the present invention.

3 is a partial cross-sectional view showing a case where an electron emission display device according to an embodiment of the present invention is applied to a field emission array (FEA) type device.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron emission display device, and more particularly, to an electron emission display device capable of suppressing arc discharge by charge charging in a vacuum container.

In general, an electron emission element may be classified into a method using a hot cathode and a method using a cold cathode according to the type of electron source.

Here, the electron-emitting device using the cold cathode is a field emitter array (FEA) type, a surface conduction emission type (SCE) type, a metal-insulation layer-metal Metal (MIM) type and Metal-Insulator-Semiconductor (MIS) type are known.

These electron emission devices are arranged in an array on a first substrate to form an electron emission device, and the electron emission device is combined with a second substrate having a light emitting unit including a fluorescent layer, an anode electrode, and the like. An emission display device is configured.

The first substrate and the second substrate are integrally bonded to each other by a sealing member, and then the inside thereof is evacuated to form a vacuum container. At this time, the inside of the vacuum container is provided with an electron emitting part, driving electrodes, and a fluorescent layer, and is an effective area in which actual light emission or image display is performed, and an invalid area in which electrode wiring is provided without contributing to the display along the outside of the effective area. Can be distinguished.

In the above-described electron emission display device, electrons are emitted from the electron emission unit under the action of the electron emission unit and the driving electrodes, and the electrons are accelerated to the second substrate to impinge the fluorescent layer to emit visible light. The marking action takes place.

However, in the electron emission display device, charge charging that accumulates inside the vacuum chamber does not quickly flow out of the electrons that excite the fluorescent layer.

Such charge charging is mainly concentrated on the substrate surface and the sealing member inner wall of the ineffective region exposed by vacuum, and greatly reduces the product characteristics such as causing an arc discharge when the electron emission display device is driven to destroy the electron emission unit.

In addition, since a high voltage of a predetermined magnitude or more is not applied to the anode electrode due to the fear of arc discharge, there is a limit in increasing the brightness of the screen.

Accordingly, an object of the present invention is to solve the above problems, and an object of the present invention is to suppress charge charging inside a vacuum container to prevent arc discharge, and to enable high voltage application to an anode electrode, thereby to increase screen brightness. An emission indicator device is provided.

In order to achieve the above object, the present invention,

A first substrate and a second substrate having an effective area and an invalid area set along the periphery of the effective area, an electron emission unit provided in the effective area of the first substrate, and an effective area of the second substrate On the light emitting unit provided in the and the sealing member which is disposed at the edge of the first substrate and the second substrate to bond the two substrates and the surface of the non-effective region of the first substrate and the surface of the non-effective region of the second substrate and the inner wall of the sealing member An electron emission display device comprising an antistatic film formed over.

The antistatic film may be made of a material having a secondary electron emission coefficient of substantially 1, for example, chromium oxide (Cr ₂ O ₃ ), and may be formed by screen printing or spray coating.

The antistatic film is an oxide film of any metal selected from the group consisting of Cr, Mn, Fe, Co, Y, Ni, Cu, Zr, Nb, Mo, Hf, Ta, W and Ru, or two kinds selected from the group. It can consist of the oxide film of the alloy containing the above metal, and can be formed by sputtering method.

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

1 and 2 are a cross-sectional view and a plan view, respectively, of an electron emission display device according to an embodiment of the present invention.

Referring to the drawings, the electron emission display device includes a first substrate 2 and a second substrate 4 which are arranged in parallel to each other at predetermined intervals. Sealing members 6 are disposed at edges of the first substrate 2 and the second substrate 4 to bond the two substrates, and the internal space is evacuated with a vacuum of approximately 10 ⁻⁶ torr to allow the first substrate 2 to be separated from the first substrate 2. The second substrate 4 and the sealing member 6 constitute the vacuum container 8.

On the opposite side of the first substrate 2 to the second substrate 4 is provided an electron emission unit 100 in which electron emission elements are arranged in an array to form an electron emission device together with the first substrate 2. Then, the electron emission device is combined with the light emitting unit 110 provided on the second substrate 4 and the second substrate 4 to constitute the electron emission display device.

The electron emission unit 100 may include driving electrodes for controlling on / off and electron emission amount of electron emission along with an electron emission unit, and may further include an electrode for correcting an electron beam path. The light emitting unit 110 includes a fluorescent layer, for example, red, green, and blue fluorescent layers, and an anode electrode for maintaining the fluorescent layers in a high potential state.

The sealing member 6 may be made of a frit bar as a whole, or may have a laminated structure of a support frame and an adhesive layer.

The anode lead wire 10 extends from the light emitting unit 110 to one side edge of the second substrate 4 over the inside and the outside of the sealing member 6, and is connected to an external driving circuit part (not shown). The high voltage required for electron beam acceleration is applied to the electrode.

In the above configuration, the area in which the electron emission unit 100 and the light emission unit 110 are provided on the first substrate 2 and the second substrate 4, respectively, to perform actual light emission or image display is called an effective area 200. The non-effective area 210 is set between the effective area 200 and the sealing member 6 along the periphery of the effective area 200.

In the present embodiment, an antistatic film 12 is formed inside the vacuum vessel 8 to suppress charge charging of the ineffective region 210. The antistatic film 12 includes a first substrate 2 and a second substrate 4 corresponding to portions of the first substrate 2 and the second substrate 4 where the surface is directly exposed in a vacuum, that is, the ineffective region 210. ) And the entire inner wall of the sealing member 6.

The antistatic film 12 is made of a material having a secondary electron emission coefficient of 1 or substantially close to 1, in which charge charging does not occur, and may be made of, for example, chromium oxide (Cr ₂ O ₃ ). The antistatic film 12 can easily form a paste containing chromium oxide or a liquid mixture by a known screen printing method, a spray coating method, or the like.

On the other hand, the antistatic film 12 is made of an oxide film of any metal selected from the group consisting of Cr, Mn, Co, Y, Ni, Zr, Nb, Mo, Hf, Ta, W and Ru, or this group It may be made of an oxide film of an alloy containing two or more metals selected from. Such an antistatic film 12 can be easily formed by a sputtering method.

Thus, the electron emission display device in which the antistatic film 12 is formed in the vacuum container 8 suppresses the charge charging generated around the ineffective region 210 and the sealing member 6, and arcing by the charge charging. The occurrence can be prevented, and as a result, breakage of the electron emitting portion, the driving electrodes, the driving circuit portion, and the like can be effectively suppressed.

In addition, even when a high voltage of approximately 10 kV or more is applied to the anode electrode, the arc discharge can be suppressed by the antistatic film 12 described above, so that a high voltage can be applied to the anode electrode, and thus a brightness increase can be expected.

The electron emission display device of the above configuration is any one of a field emission array (FEA) type, a surface conduction emission (SCE) type, a metal-insulating layer-metal (MIM) type, and a metal-insulating layer-semiconductor (MIS) type. It can be made of a type. Referring to FIG. 3, when the electron emission display device illustrated in FIGS. 1 and 2 is of FEA type, its configuration will be briefly described.

Referring to FIG. 3, cathode electrodes 14, which are first electrodes, are formed on the first substrate 2 in a stripe pattern along one direction (y-axis direction of the drawing) of the first substrate 2, and cathode electrodes The first insulating layer 16 is formed on the entire first substrate 2 while covering the 14. Gate electrodes 18 serving as second electrodes are formed on the first insulating layer 16 in a stripe pattern along a direction orthogonal to the cathode electrode 14 (x-axis direction in the drawing).

In the present exemplary embodiment, when the intersection area between the cathode electrode 14 and the gate electrode 18 is defined as a pixel area, at least one electron emission part 20 is formed in each pixel area over the cathode electrode 14, and the first insulation is formed. Openings 161 and 181 corresponding to the electron emission portions 20 are formed in the layer 16 and the gate electrode 18 to expose the electron emission portions 20 on the first substrate 2.

The electron emission unit 20 may be formed of materials emitting electrons, for example, carbon-based materials or nanometer-sized materials when an electric field is applied in a vacuum. The electron emission unit 20 may include, for example, carbon nanotubes, graphite, graphite nanofibers, diamonds, diamond-like carbon, C _60, silicon nanowires _, and combinations thereof, and a method of manufacturing the electron emission units 20. Screen printing, direct growth, chemical vapor deposition or sputtering may be applied.

A focusing electrode 22, which is a third electrode, may be formed on the gate electrodes 18 and the first insulating layer 16. A second insulating layer 24 is positioned below the focusing electrode 22 to insulate the gate electrodes 18 and the focusing electrode 22, and passes the electron beam through the second insulating layer 24 and the focusing electrode 22. Openings 241 and 221 are provided. For example, one of the openings 221 and 241 is provided in each pixel area so that the focusing electrode 22 comprehensively focuses electrons emitted from one pixel area.

Next, on one surface of the second substrate 4 opposite to the first substrate 2, the fluorescent layer 26, for example, the red, green, and blue fluorescent layers 26R, 26G, and 26B may be disposed at random intervals. The black layer 28 is formed between the fluorescent layers 26 to improve contrast of the screen. The fluorescent layer 26 is formed so that the fluorescent layers 26R, 26G, and 26B of one color correspond to the pixel areas set on the first substrate 2.

An anode electrode 30 made of a metal film such as aluminum is formed on the fluorescent layer 26 and the black layer 28. The anode electrode 30 receives a high voltage necessary for accelerating the electron beam from the outside, and reflects the visible light emitted toward the first substrate 2 among the visible light emitted from the fluorescent layer 26 toward the second substrate 4 to improve luminance. Height plays a role.

On the other hand, the anode electrode may be made of a transparent conductive film such as indium tin oxide (ITO) rather than a metal film. In this case, the anode electrode is positioned on one surface of the fluorescent layer 26 and the black layer 28 facing the second substrate 4, and may be formed in plural in a predetermined pattern. In addition, a structure in which the above-described transparent conductive film and the metal film are formed simultaneously on both surfaces of the fluorescent layer 26 and the black layer 28 as an anode electrode is also possible.

Spacers 32 are disposed between the first substrate 2 and the second substrate 4 to support the compressive force applied to the vacuum container 8 and to maintain a constant gap between the two substrates. The spacers 32 are positioned corresponding to the black layer 28 so as not to invade the fluorescent layer 26.

The electron emission display device having the above configuration is driven by supplying a predetermined voltage to the cathode electrodes 14, the gate electrodes 18, the focusing electrode 22 and the anode electrode 30 from the outside.

For example, any one of the cathode electrodes 14 and the gate electrodes 18 receives a scan driving voltage to serve as a scan electrode, and the other electrodes receive a data driving voltage to serve as a data electrode. In addition, the focusing electrode 22 receives a voltage required for electron beam focusing, for example, 0 V or a negative DC voltage of several to several tens of volts, and the anode electrode 30 requires a voltage for accelerating the electron beam, for example, several hundred to several thousand volts. DC voltage of is applied.

As a result, an electric field is formed around the electron emission part 20 in the pixels in which the voltage difference between the cathode electrode 14 and the gate electrode 18 is greater than or equal to the threshold, and electrons are emitted therefrom. The emitted electrons are focused to the center of the electron beam bundle while passing through the focusing electrode opening 221 and are attracted by the high voltage applied to the anode electrode 30 to collide with the corresponding fluorescent layer 26 to emit light.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to

As described above, the electron emission display device according to the present invention forms an antistatic film on the non-effective region and the inner wall of the sealing member to suppress the charging of the electrons and the arc discharge, thereby preventing damage to the electron emission element and the driving circuit portion. There is. In addition, the electron emission display device according to the present invention can apply a high voltage to the anode electrode without fear of arc discharge, thereby increasing the brightness of the screen.

Claims (8)

First and second substrates disposed opposite to each other and having an effective area and an invalid area set along an outer edge of the effective area; An electron emission unit provided in the effective area of the first substrate; A light emitting unit provided in the effective area of the second substrate; A sealing member disposed at an edge of the first substrate and the second substrate to bond the two substrates; And An antistatic film formed over the surface of the non-effective region of the first substrate and the surface of the non-effective region of the second substrate and the inner wall of the sealing member. Electron emission display device comprising a. The method of claim 1, And the antistatic film is formed of a material having a secondary electron emission coefficient of substantially one. The method of claim 2, An electron emission display device in which the antistatic film is made of chromium oxide (Cr ₂ O ₃ ). The method of claim 3, And the antistatic film is formed by any one of a screen printing method and a spray coating method. The method of claim 1, An electron emission display device in which the antistatic film is formed of an oxide film of any metal selected from the group consisting of Cr, Mn, Fe, Co, Y, Ni, Cu, Zr, Nb, Mo, Hf, Ta, W, and Ru. The method of claim 1, The antistatic film is electron emission comprising an oxide film of an alloy containing at least two metals selected from the group consisting of Cr, Mn, Fe, Co, Y, Ni, Cu, Zr, Nb, Mo, Hf, Ta, W and Ru. Display device. The method according to claim 5, wherein An electron emission display device in which said antistatic film is formed by sputtering. The method of claim 1, An electron emission display device wherein the electron emission unit comprises electron emission portions made of a cold cathode electron source.

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