KR20070014750A - Method of eliminating residue in electron emitting device, and method of fabricating the same - Google Patents

Abstract

A method for eliminating residues in an electron emitting device and a method for fabricating the same are provided to suppress abnormal emission due to the residues by eliminating effectively the residues from a predetermined part except for a gate electrode and an electron emission layer. A first substrate(90) includes an anode electrode(80) and a phosphor layer(70). A second substrate(110) is disposed apart from the first substrate. A cathode electrode(120) is disposed in one direction on the second substrate. A plurality of gate electrodes(140,145) are disposed across the cathode electrode. A plurality of insulating layers(130,135) are disposed between the cathode electrode and the gate electrodes. An electron emission source hole is formed at an intersection between the cathode electrode and the gate electrons. An electron emission layer(150) is disposed within the electron emission source hole. A spacer is formed between the first and second substrate. A method of eliminating a residue in an electron emitting device includes a process for positioning the electron emission device in a chamber including a discharge gas, and a process for generating plasma.

Description

Method of eliminating residue in electron emitting device, and method of fabricating the same

1 is a cross-sectional view schematically showing the configuration of an electron emitting device.

2 is a cross-sectional view schematically showing a method for removing residues of an electron emitting device according to the present invention.

<Explanation of symbols for the main parts of the drawings>

60: spacer 70: phosphor layer

80: anode electrode 90: first substrate

100: electron emission device 101: first panel

102: second panel 103: light emitting space

110: second substrate 120: cathode electrode

130: first insulator layer 131: electron emission source hole

135: second insulator layer 140: first gate electrode

145: second gate electrode 150: electron emission layer

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing residues of an electron emission device and a method of manufacturing the same. The present invention relates to a method for removing a residue to prevent the cause of abnormal light emission and a method of manufacturing an electron emitting device using the same.

In general, an electron emission device includes a method using a hot cathode and a cold cathode as an electron emission source. Examples of electron-emitting devices using a cold cathode include field emitter array (FEA), surface conduction emitter (SCE) type, metal insulator metal (MIM) type, metal insulator semiconductor (MIS) type, and ballistic electron surface emitting (BSE) type. ) And the like are known.

The FEA type uses a principle that electrons are easily released due to electric field difference in vacuum when a material having a low work function or a high β function is used as an electron emission source. Molybdenum (Mo) and silicon A tip structure with a major material such as (Si), a carbon-based material such as graphite, DLC (Diamond Like Carbon), and a recent nano tube or nano wire, etc. Devices have been developed that use nanomaterials as electron emission sources.

The SCE type is a device in which an electron emission source is formed by providing a conductive thin film between a first electrode and a second electrode disposed to face each other on a first substrate and providing a micro crack in the conductive thin film. The device uses a principle that electrons are emitted from an electron emission source that is a micro crack by applying a voltage to the electrodes to flow a current to the surface of the conductive thin film.

The MIM type and the MIS type electron emission devices each form an electron emission source having a metal-dielectric layer-metal (MIM) and metal-dielectric layer-semiconductor (MIS) structure, and are disposed between two metals or metals with a dielectric layer interposed therebetween. When a voltage is applied between semiconductors, a device using the principle of emitting electrons is moved and accelerated from a metal or semiconductor having a high electron potential toward a metal having a low electron potential.

The BSE type uses the principle that electrons travel without scattering when the size of the semiconductor is reduced to a dimension area smaller than the average free stroke of the electrons in the semiconductor, thereby forming an electron supply layer made of a metal or a semiconductor on an ohmic electrode. And an insulator layer and a metal thin film formed on the electron supply layer to emit electrons by applying power to the ohmic electrode and the metal thin film.

The present invention relates to a double FEA type electron emission device.

In recent years, FEA type electron emission devices have used needle-like materials composed mainly of carbon-based materials as materials for electron emission layers. The method of forming an electron emission layer in such an electron emission device usually uses a method of applying a paste containing acicular material. In this process, acicular material remains in portions other than the electron emitting layer, causing abnormal light emission while the electron emitting device is operating. Therefore, there is a great need to develop a process for removing such residual acicular material during the manufacturing process.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to remove the residues remaining in the portions other than the electron emitting layer during the manufacturing process, and to remove the residues of the electron emitting device and the electron emitting device using the same It is to provide a method for producing.

An object of the present invention as described above, the first substrate comprising an anode electrode and a phosphor layer; A second substrate disposed at a predetermined distance from the first substrate; A cathode electrode disposed extending in one direction on the second substrate; A gate electrode disposed to extend in a direction crossing the cathode electrode; An insulator layer disposed between the cathode electrode and the gate electrode; An electron emission source hole provided at a point where the cathode electrode and the gate electrode cross each other; An electron emission layer disposed in the electron emission hole; And a spacer for maintaining a gap between the first substrate and the second substrate, the method comprising: (a) placing the electron emitting device in a chamber filled with discharge gas; And (b) generating a plasma by applying a high (+) voltage to the anode electrode while maintaining the gate electrode at 0V.

In this case, the plasma generation in the step (b) is preferably performed by applying a positive voltage lower than the voltage applied to the anode electrode to the cathode electrode to protect the electron emission layer.

Here, the voltage applied to the anode electrode of the step (b) is 5 to 7 times the voltage applied to the cathode electrode effectively prevents (+) ions approach the electron emission layer to damage the electron emission layer It is preferable because it can block.

In addition, an object of the present invention as described above, the first substrate comprising an anode electrode and a phosphor layer; A second substrate disposed at a predetermined distance from the first substrate; A cathode electrode disposed extending in one direction on the second substrate; A gate electrode disposed to extend in a direction crossing the cathode electrode; An insulator layer disposed between the cathode electrode and the gate electrode; A method of manufacturing an electron emission device including a spacer that maintains a gap between the first substrate and the second substrate, the method comprising: forming an electron emission hole at a point where the cathode electrode and the gate electrode intersect (a) ; (B) applying a composition for forming an electron emission layer on the electron emission hole; (C) selectively curing light by illuminating the composition for forming an electron emission layer; Washing with a developer to remove the uncured composition (d); A residue removal step (e) of applying a plasma to remove the remaining material; And a firing step (f) of applying organic heat to remove organic substances contained in the electron emission layer.

Here, after the firing step (f), it is preferable that the step (g) of activating carbon-based materials on the surface of the electron emission layer to stand up may be performed to improve the electron emission characteristics of the electron emission layer.

Here, the firing step (f) is preferably performed before the residue removing step (e) because the organic material remaining in the electron emitting layer before firing has an effect of preventing damage to the electron emitting layer by the plasma.

Here, the plasma of the residue removing step (e) is generated by applying a high (+) voltage to the anode electrode while maintaining the gate electrode at 0V, in particular, the discharge is generated, in particular the discharge is the anode electrode It is preferable that the positive electrode voltage is lower than the voltage applied to the cathode electrode.

In addition, the voltage applied to the anode electrode of the step (e) is preferably 5 to 7 times the voltage applied to the cathode electrode.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the method for removing residues of the electron emitting device according to the present invention.

FIG. 1 is a diagram schematically showing the structure of an example of an electron emitting device of a double gate structure.

As shown in FIG. 1, an electron emission device 100 having a double gate structure includes a first panel 101 and a second panel 102 arranged side by side to form a light emitting space 103 that is a vacuum. A spacer 60 is provided to maintain a gap between the first panel 101 and the second panel 102.

The first panel 101 includes a first substrate 90, an anode electrode 80 disposed on a bottom surface of the first substrate 90, and a phosphor layer 70 disposed on a bottom surface of the anode electrode 80. Equipped.

The second panel 102 includes a second substrate 110, a cathode electrode 120, a first insulator layer 130, and a first gate electrode sequentially stacked on the second substrate 110. 140, a second insulator layer 135, and a second gate electrode 145. Electron emission source holes 131 having a predetermined diameter are formed in the first and second insulator layers 130 and 135, and the first and second gate electrodes 140 correspond to the electron emission source holes 131. , 145 is formed with a first gate hole and a second gate hole, respectively. The electron emission layer 150 is formed on the cathode electrode 120 exposed through the electron emission hole 131.

Here, a glass substrate is mainly used for the first and second substrates 90 and 110, and the cathode electrode 120 and the first and second gate electrodes 140 and 145 are made of a conductive material.

In addition, the electron emission layer 150 is made of a needle-like material including a carbonaceous material. In particular, it is preferable to include carbon-based materials such as carbon nanotubes (CNTs) having a small work function and large beta functions, graphite, diamond, and diamond-like carbon. In particular, since the carbon nanotubes have excellent electron emission characteristics and are easily driven at low voltages, the carbon nanotubes are advantageous for the large area of the device using them as the electron emission layer.

The electron emission device having the double gate structure can prevent the divergence of the electron beam emitted from the electron emission layer 150 by adjusting the voltage applied to the second gate electrode 145. Accordingly, the electron beam is focused to a beam spot having a smaller size at a desired position of the anode electrode 80, and thus the vivid image quality can be realized. In addition, in the electron-emitting device 100 having the double gate structure, an electric arc which may be generated between the anode electrode 80 and the cathode electrode 120 may be applied to the cathode electrode 120 rather than the anode electrode 80. It may be discharged through the closer second gate electrode 145. Therefore, the electric arc may further have an advantage of not directly affecting the electron emission layer 150, the cathode electrode 120, and the first gate electrode 140, which emit electron beams.

The manufacturing process of the second panel including the electron emission layer 150 may be performed as follows.

First, the electron emission source hole 131 is formed first. The process of forming the electron emission source hole 131 forms the cathode electrode 120 on the substrate 110, covers the insulator layer 130 thereon, and intersects the cathode electrode 120 thereon. Forming a first gate electrode 140, covering the second insulator layer 135, and forming a second gate electrode thereon in a direction parallel to the first gate electrode, followed by a mask pattern (not shown) with photoresist. And selectively etch a region where the cathode electrode 120 and the first gate electrode 140 cross each other. Of course, any method other than this method may be used.

Next, the composition for electron emission layer formation containing the acicular material excellent in the electron emission characteristic is prepared. In addition to the acicular material, the composition for forming an electron emission layer may further contain a negative photosensitive material that is cured upon receiving light and an organic material such as a binder to have a predetermined viscosity. This paste is applied to the electron emission hole 131 using a screen printing method. Only the portion of the coated paste to form the electron emission layer 150 is irradiated with UV light selectively and partially cured. Thereafter, unnecessary portions are removed by a developing process to form the electron emission layer 150 to a desired width and thickness. Of course, other methods besides these methods are also applicable.

The residues (residues) of the acicular material remain after the process of finally removing the unnecessary substances in the composition for forming an electron emission layer with the developer during the above process of forming the electron emission layer. These residues may cause abnormal light emission while the electron emitting device is operating, and thus are removed by the method described with reference to FIG. 2.

2 is a view schematically showing a method of removing residues of an electron emission device according to a first embodiment of the present invention.

As shown in FIG. 2, in order to remove residues remaining on the second panel 102 of the fabricated electron emission device, a predetermined voltage is applied to electrodes disposed in the electron emission device 100 to discharge the discharge. To generate a plasma.

For example, after placing the electron-emitting device 100 in the chamber and filling the discharge gas, 300V is applied to the anode electrode 80, 50V is applied to the cathode electrode 120, and the first and the first The two gate electrodes 140 and 145 are held at 0V or ground. When voltage is applied in this manner, a discharge occurs and a plasma is generated. Accordingly, the discharge gas is excited with positive ions and electrons, and the generated electrons move toward the anode electrode 80 by the strong positive voltage of the anode electrode 80, and the positive ions ) Burn-out the residues by reacting with the residues located outside the cathode electrode 120 without moving in the direction of the applied cathode electrode 120. The generation of the plasma can be generated in various ways in addition to the examples described herein.

The residue removal method using the plasma is preferably performed before the firing process and the activation process for the electron emission layer 150. This is because organic matter remaining in the electron emission layer before the firing process may function to prevent damage of the electron emission layer from the plasma.

Up to now, while describing the residue removal method and manufacturing method according to the present invention, an electron emission device having a double gate structure is shown and described based on this, but the residue removal method using a plasma is characterized in that only one gate electrode is located It will be apparent to those skilled in the art that they can be used even in the case. That is, in the case where there is only one gate electrode, instead of applying 0V to two gate electrodes, only the 0V is applied to one gate electrode, the effect of removing the residue described above and preventing abnormal light emission may be obtained as it is.

In addition, the process of generating the plasma may be performed using the anode electrode of the first panel after the manufacture of the second panel is combined with the first panel where the anode electrode is located, but the manufacture of the second panel is completed It can also be performed by inducing discharge to the electrode provided in the chamber and the electrode cavity provided in the second panel in a state where the discharge gas and the second panel are located in the chamber in which the electrode that can replace the anode electrode is placed. It is more preferable to work in a chamber in which a separate electrode is installed prior to bonding with the first panel since it does not have to be separated from the first panel again to perform the firing process or the activation process.

As described above, according to the present invention, even after the process of forming the electron emission layer, residues remaining in portions other than the electron emission layer including the gate electrode can be effectively removed.

Thus, abnormal light emission caused by the residue can be prevented and the light emission efficiency of the display device using the electron emission efficiency and the electron emission element can be improved.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (9)

A first substrate comprising an anode electrode and a phosphor layer; A second substrate disposed at a predetermined distance from the first substrate; A cathode electrode disposed extending in one direction on the second substrate; A gate electrode disposed to extend in a direction crossing the cathode electrode; An insulator layer disposed between the cathode electrode and the gate electrode; An electron emission source hole provided at a point where the cathode electrode and the gate electrode cross each other; An electron emission layer disposed in the electron emission hole; And A method for removing residue from an electron emission device comprising a spacer for maintaining a gap between the first substrate and the second substrate, Positioning the electron emitting device in a chamber filled with a discharge gas (a); And And (b) generating a plasma by applying a high positive voltage to an anode while maintaining the gate electrode at 0V. The method of claim 1, Plasma generation of the step (b) is, while applying a voltage (+) lower than the voltage applied to the anode electrode to the cathode electrode, the residue removal method of the electron-emitting device. The method of claim 2, And a voltage applied to the anode electrode of step (b) is 5 to 7 times the voltage applied to the cathode electrode. A first substrate comprising an anode electrode and a phosphor layer; A second substrate disposed at a predetermined distance from the first substrate; A cathode electrode disposed extending in one direction on the second substrate; A gate electrode disposed to extend in a direction crossing the cathode electrode; An insulator layer disposed between the cathode electrode and the gate electrode; A method of manufacturing an electron emission device including a spacer for maintaining a gap between the first substrate and the second substrate, (A) forming an electron emission hole at a point where the cathode electrode and the gate electrode cross each other; (B) applying a composition for forming an electron emission layer on the electron emission hole; (C) selectively curing light by illuminating the composition for forming an electron emission layer; Washing with a developer to remove the uncured composition (d); A residue removal step (e) of applying a plasma to remove the remaining material; And And a firing step (f) of applying organic heat to remove organic substances contained in the electron emission layer. The method of claim 4, wherein And after the firing step (f), activating (g) the carbon-based materials on the surface of the electron emission layer to stand upright. The method according to claim 4 or 5, And the firing step (f) is performed before the residue removing step (e). The method according to claim 4 or 5, Plasma of the residue removal step (e), And a discharge is induced by applying a high (+) voltage to the anode electrode while maintaining the gate electrode at 0V. The method of claim 7, wherein And the discharge is performed while applying a positive voltage lower than the voltage applied to the anode electrode to the cathode electrode. The method of claim 8, The voltage applied to the anode electrode of the step (b) is a method of manufacturing an electron emission device, characterized in that 5 to 7 times the voltage applied to the cathode electrode.

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