KR20070036924A - Electron emission display device and manufacturing method of the same - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron emission display device capable of suppressing damage to an anode electrode caused by a spacer. The electron emission display device according to the present invention includes a first substrate and a second substrate disposed to face each other, and are provided on the first substrate. Formed on the second substrate while covering the electron emitting portion, the driving electrodes for controlling the electron emission of the electron emitting portion, and the fluorescent layers and the fluorescent layers disposed on opposite surfaces of the second substrate with the first substrate; An anode electrode, wherein the anode electrode is formed with at least one opening in a non-light emitting region between the fluorescent layers.

Electroluminescent display, anode electrode, spacer, fluorescent layer, black layer.

Description

Electronic emission display device and manufacturing method thereof {ELECTRON EMISSION DISPLAY DEVICE AND MANUFACTURING METHOD OF THE SAME}

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

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

3 is a partial bottom view of a second substrate structure in an electron emission display device according to a first embodiment of the present invention.

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

5A to 5F are schematic views at each step for explaining a method of manufacturing an electron emission display device according to a first 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 capable of suppressing damage to an anode electrode caused by a spacer and a method of manufacturing the same.

In general, the electron emitting device 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.

Although the detailed structure of the electron emission devices differs depending on the type, the electron emission devices basically include an electron emission unit provided on the substrate, and a driving electrode for controlling electron emission of the electron emission unit. Control on / off of electron emission and electron emission amount. Such an electron emitting device may be applied to a light source such as a backlight or an electron emitting structure of an image display device.

A typical electron emission display device using an electron emission device includes an electron emission unit and driving electrodes formed on a first substrate of a pair of substrates facing each other, and a fluorescent layer on one surface of a second substrate facing the first substrate. In addition, the anode electrode for maintaining the fluorescent layer in a high potential state is formed. The edges of the first substrate and the second substrate are integrally bonded by the sealing member, and then the inside thereof is exhausted to form a vacuum container.

In addition, a plurality of spacers are disposed inside the vacuum container to maintain a constant distance between the first substrate and the second substrate, and to support the compressive force applied to the vacuum container to prevent deformation and breakage of the vacuum container. In this case, the spacers are generally disposed corresponding to the black layers positioned between the fluorescent layers so as not to invade the fluorescent layers.

In the above-mentioned electron emission display device, an anode electrode formed of a metal film such as aluminum is known. The anode is located on the surface of the fluorescent layer and the black layer, and reflects the visible light emitted toward the first substrate of the visible light emitted from the fluorescent layer to the second substrate to increase the brightness of the screen.

However, in the electron emission display device using the anode electrode, since the spacer is fixed on the anode electrode having a thin thickness of approximately several thousand ohms strong, the anode electrode is easily damaged by the force pushing the anode electrode. The damaged anode electrode may cause arc discharge and cause fatal damage to the electron emitting structure, the driving circuit part, and the like, and may cause the display beam quality to be degraded due to the deterioration of the electron beam acceleration ability around the spacer.

Accordingly, an object of the present invention is to solve the above problems, and an object of the present invention is to provide an electron emission display device capable of preventing damage to an anode electrode caused by a spacer and preventing arc discharge and display quality deterioration.

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

A first substrate and a second substrate disposed to face each other, an electron emission portion provided on the first substrate, driving electrodes for controlling electron emission of the electron emission portion, and an opposing surface of the first substrate of the second substrate; And an anode electrode formed on the second substrate while covering the fluorescent layers and the fluorescent layers spaced apart from each other, wherein the anode has at least one opening in the non-light emitting region between the fluorescent layers. Provide the device.

The anode electrode may be made of a metal film. The electron emission display device may further include spacers positioned between the first substrate and the second substrate corresponding to the non-emission area, and the anode electrode may have an opening corresponding to the spacer mounting portion.

The electron emission display device further includes a black layer positioned between the fluorescent layers, and the anode electrode is formed with at least one opening on the black layer.

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

Forming fluorescent layers in a light emitting region set on the substrate, forming a surface planarization layer on the fluorescent layers, forming a lift-off layer at a spacer mounting portion of the non-light emitting region between the fluorescent layers, Forming an anode electrode, using a lift-off layer etchant to remove the lift-off layer and the anode electrode formed on the lift-off layer, and firing the substrate to remove the surface planarization layer. Provided are methods of manufacturing the device.

The forming of the lift-off layer may include forming a photosensitive lift-off layer on the entire surface of the substrate on which the fluorescent layer is formed, and partially exposing the lift-off layer to remove the lift-off layer of the remaining portions except for the spacer mounting portion. Optionally dissolving and removing the dissolved lift-off layer.

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

1 and 2 are partially exploded perspective views and partial cross-sectional views of an electron emission display device according to a first embodiment of the present invention, and FIG. 3 is a second substrate structure of the electron emission display device according to the first embodiment of the present invention. Part of bottom view.

Referring to the drawing, the electron emission display device includes a first substrate 2 and a second substrate 4 which are disposed to be parallel to each other at predetermined intervals. 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.

A structure for emitting electrons is provided on an opposite surface of the first substrate 2 to the second substrate 4, and visible light is generated by electrons on an opposite surface of the second substrate 4 to the first substrate 2. A structure is provided for emitting any light and performing any light emission or display.

First, cathode electrodes 6 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, and cover the cathode electrodes 6. The first insulating layer 8 is formed on the entirety of the first substrate 2. Gate electrodes 10, which are second electrodes, are formed on the first insulating layer 8 in a stripe pattern along a direction orthogonal to the cathode electrode 6 (x-axis direction in the drawing).

In the present exemplary embodiment, when the intersection region of the cathode electrode 6 and the gate electrode 10 is defined as a pixel region, one or more electron emission portions 12 are formed in each pixel region over the cathode electrode 6, and the first insulation is formed. Openings 81 and 101 corresponding to the electron emission portions 12 are formed in the layer 8 and the gate electrode 10 to expose the electron emission portions 12 on the first substrate 2.

The electron emitter 12 is made of materials that emit electrons when an electric field is applied in a vacuum, such as a carbon-based material or a nanometer-sized material. The electron emission unit 12 may include, for example, carbon nanotubes, graphite, graphite nanofibers, diamonds, diamond-like carbons, C _60, silicon nanowires _, and combinations thereof. On the other hand, the electron emission unit may be formed of a tip structure having a pointed tip mainly made of molybdenum (Mo) or silicon (Si).

In the drawing, the electron emission parts 12 are formed in a circular shape and arranged in a line along the length direction of the cathode electrode 6 in each pixel area. However, the planar shape of the electron emission unit 12, the number and arrangement form per pixel area, etc. are not limited to the illustrated example and may be variously modified.

The focusing electrode 14, which is a third electrode, is formed on the gate electrode 10 and the first insulating layer 8. A second insulating layer 16 is positioned below the focusing electrode 14 to insulate the gate electrode 10 and the focusing electrode 14, and to pass the electron beam through the second insulating layer 16 and the focusing electrode 14. Openings 161 and 141 are provided. For example, one of the openings 141 and 161 is provided in each pixel area so that the focusing electrode 14 comprehensively focuses electrons emitted from one pixel area.

Next, on one surface of the second substrate 4 facing the first substrate 2, the fluorescent layer 18, for example, the red, green, and blue fluorescent layers 18R, 18G, and 18B may be disposed at random intervals. The black layer 20 is formed between the fluorescent layers 18 to improve contrast of the screen. The fluorescent layer 18 may be formed so that the fluorescent layers 18R, 18G, and 18B of one color correspond to the pixel areas set on the first substrate 2.

An anode electrode 22 made of a metal film such as aluminum is formed on the fluorescent layer 18 and the black layer 20. The anode 22 receives a high voltage necessary for accelerating the electron beam from the outside, and reflects the visible light emitted toward the first substrate 2 of the visible light emitted from the fluorescent layer 18 toward the second substrate 4 to improve luminance. Height plays a role.

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 maintain a constant gap between the two substrates. The spacers 24 are positioned corresponding to the black layer 20 so as not to invade the fluorescent layer 18.

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, one of the cathode electrode 6 and the gate electrode 10 receives a scan driving voltage to serve as a scan electrode, and the other electrode receives a data driving voltage to serve as a data electrode. In addition, the focusing electrode 14 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 22 requires a voltage for accelerating the electron beam, for example several hundreds to thousands of volts. A positive DC voltage is applied.

Then, an electric field is formed around the electron emission part 12 in the pixels in which the voltage difference between the cathode electrode 6 and the gate electrode 10 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 141, and are attracted by the high voltage applied to the anode electrode 22 to collide with the corresponding fluorescent layer 18 to emit light.

In this embodiment, the anode electrode 22 made of a metal film is formed on the second substrate 4 over the region excluding the mounting portion of the spacer 24. In other words, the anode electrode 22 forms an opening 221 corresponding to the spacer 24 at each mounting position of the spacer 24 among the non-light emitting regions where the black layer 20 is located. As a result, the spacer 24 is not in contact with the anode electrode, and is directly contacted with the black layer 20 through the anode electrode opening 221.

Here, as shown in FIG. 3, the opening 221 of the anode electrode 22 is located in a region where the spacer 24 is to be positioned so that the anode electrode 22 can be positioned at a predetermined clearance from the spacer 24. It may be formed of a region (shown as region A in FIG. 3) having a larger area than the spacer 24.

With the above-described configuration, in this embodiment, it is expected that the anode electrode 22 is prevented from being damaged in the spacer 24 mounting region, and that the adhesive force of the spacer 24 is increased. As a result, it is possible to effectively suppress the arc discharge and the degradation of the display quality around the spacer caused by the damaged anode electrode.

Referring to FIG. 4, the second embodiment of the present invention provides a configuration in which the second anode electrode 26 is further formed based on the configuration of the first embodiment described above.

The second anode electrode 26 is formed of a transparent conductive film such as indium tin oxide (ITO) instead of a metal film, and is positioned on one surface of the fluorescent layer 18 and the black layer 20 facing the second substrate 4. . The first anode electrode 22 formed of a metal film forms an opening 222 in the spacer 24 mounting portion of the black layer 20 as in the above-described embodiment.

In this case, the second anode electrode 26 is electrically connected to the first anode electrode 22 made of a metal film to maintain the fluorescent layer in a high potential state, and functions as an anode electrode together with the first anode electrode.

Next, a method of manufacturing the above-described electron emission display device will be described with reference to FIGS. 5A to 5F.

First, as shown in FIG. 5A, the black layer 20 is formed in the non-light emitting region on the second substrate 4. The black layer 20 may be formed of a thin film such as a chromium oxide film or a thick film of a carbon-based component such as graphite. In addition, red, green, and blue fluorescent layers 18R, 18G, and 18B are formed in the emission region between the black layers 20.

Subsequently, as shown in FIG. 5B, the surface planarization layer 28 is formed on the second substrate. The surface planarization layer 28 may be selectively formed only on the fluorescent layers 18, for example. This is to increase the adhesion of the anode electrode to the second substrate by directly contacting the anode electrode formed later. The surface planarization layer consists of a polymeric material that decomposes at a firing temperature of approximately 430 ° C.

As shown in FIG. 3, a portion where the spacer 24 is to be positioned is determined, and a lift-off layer 30 is formed on the portion as shown in FIG. 5C.

In this process, a photosensitive material is mixed with a lift-off material to form a photosensitive lift-off layer on the front of the fluorescent layer 18 and the black layer 20, and the remaining portions except for the spacer 24 mounting portion are exposed and dissolved. It is then easily achieved through the process of removing the dissolved lift-off layer. The lift-off layer may be composed of, for example, a mixture of polyvinyl alcohol (PVA) and ammonium dichromate.

As shown in FIG. 5D, the anode electrode 22 is formed by vapor deposition or sputtering of a metal material, for example, aluminum, on the entire surface of the second substrate 4 on which the lift-off layer 30 is formed. The anode electrode 22 is formed thereon in the shape of the surface planarization layer 28 formed on the fluorescent layer 18 and the lift-off layer 30 formed at the spacer mounting site.

Next, as shown in FIG. 5E, the second substrate 4 on which the anode electrode 22 is formed is wet etched on the lift-off layer etchant to remove the lift-off layer 30. The lift-off layer etchant may include hydrogen peroxide or a mixture of hydrogen peroxide and ammonium hydroxide. In this process, the lift-off layer 30 and the anode electrode formed thereon are removed together. Therefore, the anode electrode 22 has an opening 221 which directly exposes the black layer 20 for each spacer 24 mounting portion.

Subsequently, the second substrate 4 is fired to remove the surface planarization layer 28 to complete the structure of the second substrate 4 shown in FIG. 5F. At this time, the anode electrode on the fluorescent layer 18 is positioned with a predetermined gap with the fluorescent layer 18 by the surface planarization layer 28 removed, and the anode electrode on the black layer 20 is the black layer 20. It is formed in direct contact with.

Finally, the electron emission part 12 and the driving electrodes 6, 10, 14 for controlling the electrons are formed on the first substrate 2, the spacers 24 are disposed, and then the first substrate is formed using the sealing member. (2) and the edge of the second substrate 4 are joined to form a vacuum container, and the inside of the vacuum container is exhausted through an exhaust port (not shown) to complete the electron emission display device. Here, the spacers 24 are mounted in direct contact with the black layer 20 through the opening 221 formed in the anode electrode 22.

In the above description, the field emission array (FEA) type electron emission display device made of materials in which the electron emission portion emits electrons by an electric field in vacuum has been described. However, the present invention is not limited to the FEA type, but the electron emission portion and the anode electrode. And other types of electron emission displays having a fluorescent layer.

In addition, while 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 belongs to the scope of the invention.

As such, the electron emission display device according to the present invention has an effect of preventing the anode electrode from being damaged by the spacer by removing the anode electrode at the spacer mounting portion, and preventing the arc discharge that may be generated by the damaged anode electrode. . Therefore, since arc discharge is suppressed and a higher voltage can be applied to the anode, the brightness of the screen is increased.

Claims (10)

A first substrate and a second substrate disposed to face each other; An electron emission unit provided on the first substrate; Drive electrodes for controlling electron emission of the electron emission unit; Fluorescent layers spaced apart from each other on the opposite surface of the second substrate to the first substrate; And An anode electrode formed on the second substrate while covering the fluorescent layers; And the anode electrode has at least one opening in a non-light emitting region between the fluorescent layers. The method of claim 1, And an anode electrode made of a metal film. The method of claim 1, And a spacer disposed between the first substrate and the second substrate corresponding to the non-light emitting region, wherein the anode electrode has an opening corresponding to the spacer mounting portion. The method of claim 1, And a black layer positioned between the fluorescent layers. The method according to any one of claims 1 to 4, And a transparent anode positioned on one surface of the fluorescent layers facing the second substrate. (a) forming fluorescent layers in a light emitting region set on the substrate; (b) forming a surface planarization layer over the fluorescent layers; (c) forming a lift-off layer at a spacer mounting portion of the non-light emitting region between the fluorescent layers; (d) forming an anode electrode on an entire surface of the substrate; (e) removing the lift-off layer and the anode electrode formed on the lift-off layer using a lift-off layer etchant; (f) firing the substrate to remove the surface planarization layer Method of manufacturing an electron emission display device comprising a. The method of claim 6, In step (c), (i) forming a photosensitive lift-off layer on one surface of the substrate on which the fluorescent layer is formed; (Ii) partially exposing the lift-off layer to selectively dissolve the lift-off layer at portions other than the spacer mounting site; (Iii) removing the dissolved lift-off layer Method of manufacturing an electron emission display device comprising a. The method of claim 6, A method of manufacturing an electron emission display device, wherein the anode electrode comprises aluminum (Al). The method of claim 6, And (d) vapor-depositing or sputtering a metal material. The method of claim 9, The lift-off etchant comprises hydrogen peroxide or a mixture of hydrogen peroxide and ammonium hydroxide.

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