KR20070046658A - Electron emission display device - Google Patents

Abstract

The present invention relates to an electron emission display device, and more particularly, to an electron emission display device according to an embodiment of the present invention, a first substrate and a second substrate disposed to face each other, a driving electrode provided on the first substrate and And electron emission parts controlled by the driving electrodes, a focusing electrode positioned to be insulated from the driving electrodes on the driving electrodes, forming openings for passing an electron beam, and a red formed on one surface of the second substrate. And green and blue fluorescent layers, an anode formed on one surface of the fluorescent layers, a plurality of spacers maintaining a distance between the first substrate and the second substrate, and at least one of the focusing electrodes A resistive layer is included in the site | part to make.

Electron emission, spacer, focusing electrode, resistive layer

Description

Electron Emission Display Device {ELECTRON EMISSION DISPLAY DEVICE}

1 is a partially exploded perspective view of an electron emission display device according to an exemplary embodiment of the present invention.

FIG. 2 is a partial cross-sectional view of the electron emission display device shown in FIG. 1. FIG.

3 is a partial cross-sectional view of an electron emission display device according to another exemplary embodiment of the present invention.

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 having improved distortion of an electron beam due to a difference in resistance between a focusing electrode and a spacer.

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

Here, the electron emission device using the cold cathode may be a field emitter array (FEA) type, a surface conduction emission type (SCE) type, metal Metal-Insulator-Metal (hereinafter referred to as 'MIM') type and Metal-Insulator-Semiconductor (hereinafter referred to as 'MIS') type are known.

Among them, the FEA type electron emission device includes an electron emission unit and driving electrodes for controlling electron emission of the electron emission unit, and includes one cathode electrode and one gate electrode, and has a low work function as a material of the electron emission unit. Or a high aspect ratio material, such as molybdenum (Mo) or silicon (Si), with a sharp tip structure, or an electric field in vacuum using carbon-based materials such as carbon nanotubes and graphite and diamond-like carbon. By using the principle that the electron is easily emitted by.

On the other hand, the electron emission elements are formed in an array on one substrate to form an electron emission device, and the electron emission device is combined with another substrate having a light emitting unit composed of a fluorescent layer and an anode electrode to emit electrons. A display device (electron emission display device) is constituted.

That is, the conventional electron emitting device includes a plurality of driving electrodes that function as scan electrodes and data electrodes in addition to the electron emitting part, so that the electron emission amount and the electron emission amount per pixel are controlled by the action of the electron emitting part and the driving electrodes. To control. The electron emission display device excites the fluorescent layer with the electrons emitted from the electron emission unit to perform a predetermined light emission or display function.

The electron emission display device has a plurality of spacers therein to space the two substrates constituting the vacuum container. This spacer is exposed to the interior space of the vacuum where the flow of electrons continues to occur.

On the other hand, the electron emission display device includes a focusing electrode at the top for focusing the electron beam emitted from the electron emission part, and the spacer is usually disposed on the focusing electrode to discharge the charge charged therefrom to the outside through the focusing electrode. However, the spacer is generally formed of a high resistance material, and the focusing electrode is made of a metal, and thus the electron beam emitted around the spacer does not go straight due to a difference in resistance between the spacer and the focusing electrode, which causes distortion.

Accordingly, an object of the present invention is to provide an electron emission display device capable of canceling a difference in resistance between a spacer and a focusing electrode so as to maintain the straightness of an electron beam emitted around the spacer. have.

In order to achieve the above object, an electron emission display device according to an exemplary embodiment of the present invention includes a first substrate and a second substrate disposed opposite to each other, drive electrodes provided on the first substrate, and the drive electrodes. Electron emission parts controlled by the light emitting device, a focusing electrode which is insulated from the driving electrodes on the driving electrodes, and forms openings for passing an electron beam, and red, green, and blue fluorescent lights formed on one surface of the second substrate. Layers, an anode electrode formed on one surface of the fluorescent layers, a plurality of spacers for maintaining a distance between the first substrate and the second substrate, and a resistive layer on at least a portion of the focusing electrode adjacent to the spacer It includes.

In addition, the resistance layer may be formed of the same material as the spacer, and in this case, the resistance layer may be formed of glass or ceramic.

In addition, the focusing electrode may be formed of a single body, and the resistance layer may be formed on the entire surface of the focusing electrode.

In addition, the spacer may be formed on the resistive layer or may be connected to the focusing electrode through a hole formed in the resistive layer.

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

1 is a partially exploded perspective view of an electron emission display device according to an exemplary embodiment, and FIG. 2 is a partial cross-sectional view of the electron emission display device illustrated in FIG. 1.

Referring to the drawings, the electron emission display device according to the exemplary embodiment of the present invention includes a first substrate 2 and a second substrate 4 which are arranged in parallel to each other at a predetermined interval. Sealing members (not shown) are disposed at the 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 bonded. ), The second substrate 4 and the sealing member constitute a vacuum container.

On the opposite surface of the first substrate 2 to the second substrate 4, electron emission elements are arranged in an array to form an electron emission device together with the first substrate 2, and the electron emission device is a second substrate. (4) and the light emitting unit provided on the second substrate 4 to form an electron emission display device.

First, the cathode electrodes 6, which are the first driving electrodes, are formed on the first substrate 2 in a stripe pattern along one direction (y-axis direction in FIG. 1) of the first substrate 2, and the cathode electrodes ( Covering 6), the first insulating layer 8 is formed on the entire first substrate 2. Gate electrodes 10 serving as second driving electrodes are formed on the first insulating layer 8 in a stripe pattern along a direction orthogonal to the cathode electrode 6 (the x-axis direction in FIG. 1).

An intersection area between the cathode electrodes 6 and the gate electrodes 10 forms a unit pixel, and electron emission parts 12 are formed in each unit pixel above the cathode electrodes 6. In addition, openings 82 and 102 corresponding to the respective electron emission parts 12 are formed in the first insulating layer 8 and the gate electrodes 10, so that the electron emission parts 12 are formed on the first substrate 2. To be exposed.

The electron emission unit 12 may be formed of materials emitting electrons when a electric field is applied in a vacuum, such as a carbon-based material or a nanometer (nm) size material. The electron emission unit 12 may include carbon nanotubes (CNT), graphite, graphite nanofibers, diamonds, diamond-like carbons (DLC), fullerenes (C ₆₀ ), silicon nanowires, and combinations thereof.

On the other hand, the electron emission portion may be formed of a tip structure having a pointed tip mainly made of molybdenum (Mo) or silicon (Si).

The electron emitters 12 may be positioned in a line along the length direction of one of the cathode electrode 6 and the gate electrode 10, for example, the cathode electrode 6, in each unit pixel, and may have a circular plane It may be formed to have a shape. The arrangement of the electron emission units 12 and the planar shape of the electron emission units 12 for each pixel are not limited to the illustrated example, and may be variously modified.

In addition, in the above, the structure in which the gate electrodes 10 are positioned on the cathode electrodes 6 with the first insulating layer 8 therebetween has been described, but the gate electrodes have the first insulating layer interposed therebetween. A structure positioned below the electrodes is also possible, in which case the electron emission parts may be formed on the side of the cathode electrode over the first insulating layer.

The focusing electrode 14 is formed on the gate electrodes 10 and the first insulating layer 8. A second insulating layer 16 is positioned below the focusing electrode 14 to insulate the gate electrodes 10 and the focusing electrode 14, and passes the electron beam through the focusing electrode 14 and the second insulating layer 16. Openings 142 and 162 are provided respectively.

One opening 142 of the focusing electrode 14 is formed for each unit pixel so that the focusing electrode 14 collectively focuses electrons emitted from one unit pixel, or one for each opening 102 of the gate electrode 10. Thus, the electrons emitted from each electron emitter 12 may be individually focused. In the drawings, the former case is illustrated as an example.

In addition, the focusing electrode 14 may have a single body on the entire first substrate 2.

Next, a fluorescent layer 18, for example, red, green, and blue fluorescent layers 18, are formed on one surface of the second substrate 4 opposite to the first substrate 2 at random intervals from each other. Then, a black layer 20 is formed between the fluorescent layers 18 to improve the contrast of the screen. The fluorescent layer 18 may be disposed such that one fluorescent layer 18 corresponds to each unit pixel set in the first substrate 2.

An anode electrode 22 made of a metal film such as aluminum (Al) is formed on one surface of the fluorescent layer 18 and the black layer 20. The anode 22 receives the high voltage necessary for accelerating the electron beam from the outside to maintain the fluorescent layer 18 in a high potential state, and visible light emitted toward the first substrate 2 of the visible light emitted from the fluorescent layer 18. Is reflected to the second substrate 4 side to increase the brightness of the screen.

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 is positioned on one surface of the fluorescent layer 18 and the black layer 20 facing the second substrate 4. In addition, the anode electrode may have a structure in which the above-mentioned transparent conductive film and a metal film are simultaneously used.

In addition, spacers 24 are disposed between the first substrate 2 and the second substrate 4 to support the compressive force applied to the vacuum container and to keep the distance between the two substrates constant. The spacers 24 are positioned corresponding to the black layer 20 so as not to invade the fluorescent layer 18. The spacers may have various shapes such as a wall shape and a circular column shape. In FIG. 1, the spacers are illustrated as an example.

The spacer 24 is made of glass or ceramic, which is a high resistance material, in order to prevent a short between the focusing electrode 14 and the anode electrode 22.

In this embodiment, a resistive layer 26 is stacked on the focusing electrode 14, and a spacer 24 is formed between the resistive layer 26 and the anode electrode 22. The resistive layer 26 prevents an electron beam distortion that may occur due to a difference in resistance between the spacer 24 and the focusing electrode 14 when the electron beam emitted from the spacer 24 and the adjacent opening 142. That is, since the spacer 24 is made of a high resistance material and has a high resistance value, and the focusing electrode 14 is made of metal and has a low resistance value, the resistance value difference thereof is formed very large, and the resistance layer 26 is formed of a spacer. Since the resistance difference between the spacer 24 and the spacer 24 is formed on the focusing electrode 14 by using a material having a small difference between the resistance 24 and the resistance value, a uniform resistance environment is formed around the electron beam.

The resistive layer 26 is preferably formed of the same material (glass or ceramic) that has no resistance difference from the spacer 24, that is, the material of the spacer 24.

As shown in FIG. 2, the resistive layer 26 may be formed on the entire surface of the focusing electrode 14, and the resistive layer 26 may be formed in the opening 142 of the focusing electrode 14. Another corresponding opening 262 is provided. In addition, the resistive layer 26 may be formed at least partially on the focusing electrode 14 adjacent to the spacer 14.

3 is a partial cross-sectional view of an electron emission display device according to another exemplary embodiment, and illustrates a structure in which a resistive layer is directly connected to a focusing electrode.

As shown in FIG. 3, the spacer 24 is inserted into a hole 264 formed in the resistance layer 26 to directly contact the focusing electrode 14. Therefore, when the spacer 24 is charged, the charge can be sent to the outside through the focusing electrode 14.

The electron emission display device having the above configuration is driven by supplying a predetermined voltage to the cathode electrode 6, the gate electrode 10, the focusing electrode 14 and the anode electrode 22 from the outside.

For example, any one of the cathode electrode 6 and the gate electrode 10 receives a scan driving voltage to serve as scan electrodes, and the other electrodes receive a data driving voltage to serve as data electrodes. The focusing electrode 14 receives a voltage required for focusing, for example, 0 V or a negative DC voltage of several to several tens of volts, and the anode electrode 22 has a voltage necessary for accelerating the electron beam, for example, a quantity of several hundred to several thousand volts. DC voltage is applied.

As a result, an electric field is formed around the electron emission unit 12 in the unit pixels in which the voltage difference between the cathode electrode 6 and the gate electrode 10 is greater than or equal to a threshold, and electrons are emitted therefrom. The emitted electrons are focused to the center of the electron beam bundle while passing through the opening 142 of the focusing electrode 14, and are attracted to the fluorescent layer 18 of the corresponding unit pixel by being attracted by the high voltage applied to the anode electrode 22. It emits light.

In the above-described driving process, the spacer 24 is formed on the resistance layer 26 having substantially the same resistance value, so as to reduce the resistance difference between the spacer 24 and the focusing electrode 14, and thus the electron beam has a resistance difference. This maintains the original electron beam path without biasing either side.

The electron emission display device according to the embodiment of the present invention has been applied only to the field emission array (FEA) type, but is not limited thereto, and the surface conduction emission (SCE) type, the metal-insulating layer-metal (MIM) type, and the metal type. -It can be applied in various ways such as insulation layer-semiconductor (MIS) type.

In addition, although the preferred embodiment of the present invention has 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 is within the scope of the present invention.

As described above, the electron emission display device according to the exemplary embodiment of the present invention includes a resistance layer on the focusing electrode, thereby eliminating the distortion of the electron beam, which may be caused by the resistance unevenness between the spacer and the focusing electrode, and thus the screen. In order to realize high quality image by eliminating the spacer detection phenomenon caused by the difference in luminance around the spacer.

Claims (9)

A first substrate and a second substrate disposed to face each other; Drive electrodes provided on the first substrate; Electron emission parts controlled by the drive electrodes; A focusing electrode which is insulated from the driving electrodes on the driving electrodes and forms openings for passing an electron beam; Red, green, and blue fluorescent layers formed on one surface of the second substrate; An anode electrode formed on one surface of the fluorescent layers; A plurality of spacers maintaining a distance between the first substrate and the second substrate; And And a resistive layer on at least a portion of the focusing electrode adjacent to the spacer. The method of claim 1, And the resistive layer is formed of the same material as the spacer. The method of claim 2, And the resistive layer is formed of glass or ceramic. The method of claim 3, The focusing electrode is composed of a single body, The electron emission display device in which the said resistance layer is formed in the whole surface of a focusing electrode. The method of claim 4, wherein And the spacer is formed over the resistive layer. The method of claim 4, wherein And the spacer is connected to the focusing electrode through a hole formed in the resistive layer. The method of claim 2, The driving electrodes include cathode electrodes and gate electrodes which are formed in different layers with the insulating layer interposed therebetween and formed in an intersecting direction. And the electron emission portions are formed on the cathode electrode at every intersection of the cathode electrode and the gate electrode. The method of claim 7, wherein And one opening for passing the electron beam is formed at each intersection of the cathode electrode and the gate electrode. The method of claim 7, wherein And the electron emission unit comprises at least one material selected from the group consisting of carbon nanotubes, graphite, graphite nanofibers, diamonds, diamond-like carbons, fullerenes (C ₆₀ ), and silicon nanowires.

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