KR100258794B1 - Method of field emission display manufacture - Google Patents

Abstract

PURPOSE: A method of making field emission display is provided to be easy to align upper and lower substrates and a spacer and have no flow of a spacer after aligning. CONSTITUTION: A plurality of cathode electrodes(204) and emitters(203) are formed on a lower substrate and an insulation layer and a gate electrode are formed between the emitters. A plurality of anode electrodes and fluorescent substances(208) are formed on an upper substrate(206) so as to be intersected with the cathode electrodes. A spacer(201) is formed so that the upper substrate and the lower substrate are spaced apart to each other. The spacer is formed so as to have a bead shape with a predetermined diameter. A plurality of grooves(201a) are formed on the upper substrate so as to be spaced apart. A plurality of grooves(206a) are formed on the lower substrate so as to correspond to the grooves formed on the upper substrate. The spacer is placed between the grooves on the upper substrate and the grooves on the lower substrate.

Description

Field emission device manufacturing method

1 is a cross-sectional view of a FED using a spacer according to the prior art.

2 is a cross-sectional view of an FED in accordance with an embodiment of the present invention.

3 is a view for explaining the sealing process of FIG.

* Explanation of symbols for main parts of the drawings

201: lower substrate 202: emitter

203: cathode electrode 204: insulating layer

205: gate electrode 206: upper electrode

207 transparent electrode 208 phosphor

209: secondary glass substrate 210: hole

211: spacer 212: exhaust tube

301: sealant 302: uneven groove

303: Resin

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing a field emission device, and more particularly to a method for manufacturing a field emission device in which a spacer is formed of transparent glass beads.

In general, a pressure sensor or the like of the display element requires vacuum packaging. The display elements requiring the vacuum packaging include a cathode ray tube (CRT), a plasma display panel (hereinafter referred to as PDP), a field emission display (hereinafter referred to as FED), and a vacuum fluorescent display. Devices (Vacuum Fluorescent Display: hereinafter referred to as VFD). Among the display elements, PDP is required to have a low vacuum degree of several hundred torr because electrons and protons generated by discharging an operating gas such as neon in a space filled with the phosphor collide with the phosphor to display a screen. However, FED, VFD, and the like, which are most widely used at present, display a screen by the generated electrons colliding with a phosphor, and thus require a high vacuum to increase the mean free path of the electrons. In particular, FED requires a high vacuum of about 10 ^-6 Torr, so a high vacuum packaging technique is required.

However, in the high vacuum packaged FED, a pressure of about 1 kg / cm · sec ² acts on the upper substrate and the lower substrate constituting the display element by the pressure difference between the inside and the outside, and this pressure is the upper substrate constituting the FED. The lower and lower substrates are bent inward and in severe cases abut. Therefore, a spacer is formed between the upper substrate and the lower substrate to prevent the upper substrate and the lower substrate from bending and to maintain a predetermined distance, for example, 100 to 200 μm.

1 is a cross-sectional view of a FED using a spacer according to the prior art.

The FED includes a lower substrate 101 on which a plurality of stripe cathode electrodes 103 are formed, and an upper substrate 106 on which a plurality of stripe shaped transparent electrodes 103 intersect the cathode electrode 103. ).

The upper substrate 106 is positioned in front of the viewer, and phosphors 108 emitting light by collision with electrons are formed on the surface of the transparent electrode 107, respectively. Therefore, the upper substrate 106 and the transparent electrode 107 are formed of a transparent material.

The lower substrate 101 is located on the back of the viewer and has a conical shape on the surface of the cathode electrode 102 to form a plurality of emitters 103 which emit electrons by generation of an electric field. In addition, an insulating layer 104 is formed between the emitters 103, and a gate electrode 105 is formed on the insulating layer 104.

The upper substrate 106 and the lower substrate 101 may be spaced apart by a plurality of spacers 110 such that the phosphor 108 and the emitter 103 face the space 109, for example, 100. ~ 200㎛ is attached spaced apart. The spacer 110 has a high hardness and insulation property such as ceramics including glass, oxide, or nitride having a wall-like shape at the corners of the upper substrate 106 and the lower substrate 101 and a cylindrical shape at the center thereof. It is made of a good material or an insulating material such as a polymer containing polyimide. The spacer 110 not only attaches the edges of the upper substrate 106 and the lower substrate 101, but in the case of a large screen, hundreds to thousands are formed at the center, and the pressure difference between the space 109 and the atmospheric pressure is external. As a result, the upper substrate 106 and the lower substrate 101 are prevented from contacting each other.

In forming the spacer 110 of the FED having the above-described structure, conventionally, a screen printing method on the upper portion of the lower substrate 101, a method of forming the spacer 110 with polyimide, or a photosensitive glass ( photosensitive glass).

In the above, the screen printing method is to form a shape of the spacer by screenprinting a plurality of slurries, which are mainly composed of glass powder, and then to bake, and when the spacer 110 is formed of polyimide, first, the cathode substrate 102 After applying the polyimide on the)) to form a pattern (pattern) using a mask thereon, through the development process and etching process to remove the desired portion to produce a spacer 110 in a columnar shape.

In addition, the spacer is formed through an etching process and various semiconductor manufacturing processes using photosensitive glass.

However, in the method of forming the spacer according to the prior art as described above, the screen printing method mainly uses frit glass, but it is difficult to prevent contamination on the emitter 103, and to adjust the height several times. Printing is inevitable, so height adjustment is very difficult. In addition, when the spacer 110 is formed of polyimide, it is completed through a very difficult process, there is a risk of damage and contamination of the emitter 103, and there is a problem that the mechanical deformation is somewhat lower than that of other materials. In addition, the photosensitive glass has a problem that it is very difficult to align between the upper and lower substrates 106 and 101 after the etching process is finished.

Accordingly, an object of the present invention is to provide a method of manufacturing a field emission display device in which the upper and lower substrates and the spacers are easily aligned and there is no flow of the spacers after the alignment.

In order to achieve the above object, the present invention provides a plurality of stripe-shaped cathode electrodes and emitters, a lower substrate having an insulating layer and a gate electrode formed between the emitters, and a plurality of stripe-shaped anodes intersecting the cathode electrodes. A field emission display device comprising: an upper substrate having electrodes and phosphors formed thereon; and spacers for keeping the upper substrate and the lower substrate spaced apart from each other by a predetermined distance; Forming the spacers in the shape of beads having a predetermined diameter, forming grooves at predetermined intervals on the upper substrate, forming grooves on the lower substrate corresponding to grooves formed on the upper substrate, And arranging the bead-shaped spacers between the grooves formed in the upper substrate and the grooves formed in the lower substrate.

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

2 is a cross-sectional view showing an embodiment of the present invention.

First, the spacer 201 is formed in the form of beads using transparent glass, but a spacer 211 having a diameter of about 100 μm to 200 μm is formed.

In addition, the upper substrate 206 is formed of a transparent cured glass (pyrex) containing sodium (Na), and a round etching is performed on the upper substrate 206 by unit pixel intervals or a plurality of unit pixel intervals. 206a). Phosphors formed of indium-tin-oxide (ITO), which is a transparent conductive material, on the surface opposite to the viewer of the upper substrate 206 and emitting light by collision with electrons on the surface of the transparent electrode 207 ( 208 respectively.

The lower substrate 201 is located on the back of the viewer and is formed of hardened glass containing sodium or formed of a silicon wafer, similarly to the upper substrate 206, and a groove 206a formed on the upper substrate 206. The groove 201a is formed on the lower substrate 201 to correspond to the. In addition, the cathode electrode 203 is formed of a conductive metal such as chromium (Cr), and a plurality of emi emitting molybdenum (Mo) or tungsten (W) on the surface of the cathode electrode 203 in the form of a cone. Form an emitter (202).

Further, an insulator 204 is formed between the emitters 202 on the cathode electrode 203, and a gate electrode 205 is formed on the insulator 204 so as to face the cathode electrode 203 in common. do. The gate electrode 205 facilitates the emission of electrons from the emitter 202. In addition, when the lower substrate 201 is formed of a silicon wafer, the auxiliary glass substrate 209 is electrostatically bonded to the lower substrate 201 to prevent breakage of the lower substrate 201. In this case, the lower substrate 201 and the auxiliary glass substrate are electrostatically bonded. The two substrates 201 and 209 are baked before the electrostatic bonding in order to eliminate residual gas generated during the electrostatic bonding of 209.

The transparent glass bead spacer 211 is inserted between the upper and lower substrates 206 and 201 formed as described above, and the two substrates 206 and 201 are aligned. That is, after placing the transparent glass bead spacer 211 using the microscope in the groove 201a formed in the unit substrate or a plurality of unit pixel intervals on the lower substrate 201, the groove 206a formed in the upper substrate 206 and The transparent glass beads spacers 211 are aligned.

When the alignment is completed, as shown in FIG. 3, the edge of the upper substrate 206 is formed into the sealant 301 of the rectangular pillar, and the edge of the lower substrate 201 corresponding to the uneven groove 302 is formed. After forming, the resin 303 is placed in the uneven groove 302 to be sealed through a firing process in a furnace.

In addition, the getter is applied to the edge of the FED to capture the residual gas in the internal space of the FED to improve the degree of vacuum. The getter includes titanium (Ti), silver-titanium alloy (Ag-Ti), and tantalum (Ta). , Zirconium (Zr), zirconium-aluminum alloy (Zr-Al), zirconium-nickel and the like are used.

Then, one side of the exhaust tube 212 is inserted into the hole 210 formed by forming a hole 210 in a predetermined portion where the cathode electrode 203 of the lower substrate 201 is not formed, and then sealing the gas. . Then, the other side of the exhaust tube 212 is connected to a vacuum pump (not shown), and then the residual gas in the space inside the FED is evacuated using the vacuum pump. In addition, while the FED space maintains a vacuum, the exhaust tube 212 is rotated and elongated while being heated by a torch or the like so as to separate the FED and the vacuum pump.

As described above, according to the present invention, the spacers are formed of transparent glass beads, so that the upper and lower substrates and the spacers are easily aligned, there is no flow of the spacers after the alignment, and the spacers are transparent glass beads. There is.

Claims (4)

A lower substrate having a plurality of stripe cathode electrodes and emitters formed therebetween, the upper substrate having an insulating layer and a gate electrode formed therebetween, a plurality of stripe anode electrodes and phosphors intersecting the cathode electrodes; A field emission display device comprising a spacer for keeping the upper substrate and the lower substrate spaced apart from each other by a predetermined distance; Forming the spacers in the shape of beads having a predetermined diameter, forming grooves at predetermined intervals on the upper substrate, forming grooves on the lower substrate corresponding to grooves formed on the upper substrate, And arranging the bead-shaped spacers between the grooves formed in the upper substrate and the grooves formed in the lower substrate. The method of claim 1, wherein the spacer is formed to have a diameter of about 100 μm to about 200 μm. The method for manufacturing a field emission display device according to claim 1 or 2, wherein the spacer is formed of transparent glass. The method of claim 1, wherein the groove of the upper substrate and the groove of the lower substrate are etched in a rounded form.