JP2008004280A - Flat panel display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flat panel display device capable of reducing generation of damage on an anode electrode and a cold cathode field electron emission element caused by discharge. <P>SOLUTION: The flat panel display device is formed by joining a cathode panel, which includes a plurality of electron emitting regions, and an anode panel which includes a phosphor region and an anode electrode, on their peripheral edge parts. The anode panel is provided with a substrate, the phosphor region formed on a display region of the substrate, a light reflection layer formed on the phosphor region, and the anode electrode formed on a light reflection layer for covering the display region. The light reflection layer is formed of insulating material, and the anode electrode is formed of resistance material. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a flat display device.

  As an image display device that can replace the mainstream cathode ray tube (CRT), various types of flat display devices have been studied. Examples of such a flat display device include a liquid crystal display device (LCD), an electroluminescence display device (ELD), and a plasma display device (PDP). In addition, development of a flat display device incorporating a cathode panel equipped with an electron-emitting device is also in progress. Here, as the electron-emitting device, a cold cathode field electron-emitting device, a metal / insulating film / metal-type device (also called MIM device), and a surface conduction electron-emitting device are known. A flat display device incorporating a cathode panel provided with the electron-emitting device is attracting attention from the viewpoint of high-resolution, high-luminance color display and low power consumption.

  In general, a cold cathode field emission display device (hereinafter sometimes abbreviated as a display device), which is a flat display device incorporating a cold cathode field emission device, has a sub-pixel arranged in a two-dimensional matrix. A cathode panel having a corresponding electron emission region and an anode panel having a phosphor region that emits light when excited by collision with electrons emitted from the electron emission region are arranged to face each other through a space held in a vacuum. Have a configuration. The electron emission region is usually provided with one or a plurality of cold cathode field emission devices (hereinafter sometimes abbreviated as field emission devices). Examples of field emission devices include Spindt type, flat type, edge type, and planar type.

  FIG. 10 shows a schematic plan view of the anode electrode in the display device disclosed in Embodiment 2 of the invention of Japanese Patent Application Laid-Open No. 2004-158232, and arrows AA, BB, and C in FIG. Schematic partial end views of the anode panel AP along -C are shown in FIGS. 11 (A), 11 (B), and 11 (C). A schematic partial end view of this display device is shown in FIG. 12, and a schematic partial perspective view of the anode panel AP and the cathode panel CP is shown in FIG. In FIG. 13, illustration of the anode electrode unit is omitted and the illustration of the partition wall is also omitted for simplification of the drawing.

  In this display device, a cathode panel CP provided with a plurality of electron emission regions and an anode panel AP provided with a phosphor region and an anode electrode are joined at their peripheral portions. A plurality of field emission elements are provided in the electron emission region.

  The field emission device shown in FIG. 12 is a so-called Spindt type field emission device having a conical electron emission portion. The field emission device includes a cathode electrode 11 formed on a support 10, an insulating layer 12 formed on the support 10 and the cathode electrode 11, a gate electrode 13 formed on the insulating layer 12, a gate An opening 14 provided in the electrode 13 and the insulating layer 12 (a first opening 14A provided in the gate electrode 13 and a second opening 14B provided in the insulating layer 12), and a second opening 14B It comprises a conical electron emission portion 15 formed on the cathode electrode 11 located at the bottom. In general, the cathode electrode 11 and the gate electrode 13 are each formed in a strip shape in a direction in which the projected images of both the electrodes 11 and 13 are orthogonal to each other. An overlapping region where the strip-shaped cathode electrode 11 and the strip-shaped gate electrode 13 overlap is an electron emission region EA, which corresponds to a region of one subpixel. The electron emission areas EA are usually arranged in a two-dimensional matrix within the effective area of the cathode panel CP (area corresponding to the display area of the display device).

  On the other hand, the anode panel AP is formed on the substrate 120, the unit phosphor region 121 formed on the substrate 120 and having a predetermined pattern, the anode electrode 130 formed on the unit phosphor region 121, and the power feeding unit 140 (see FIG. 12). (Not shown). The anode electrode 130 as a whole has a shape that covers a rectangular effective area, and is made of an aluminum thin film. The anode electrode 130 has a function as a reflection film that reflects light emitted from the unit phosphor region 121. A light absorption layer (black matrix) 122 is formed on the substrate 120 between the unit phosphor region 121 and the unit phosphor region 121. A partition wall 123 is formed on the light absorption layer 122. The planar shape of the partition wall 123 is a lattice shape (cross-beam shape), and has a shape surrounding one subpixel (unit phosphor region).

  Here, one subpixel is a group of field emission elements provided in an overlapping region of the cathode electrode 11 and the gate electrode 13 on the cathode panel side, and unit fluorescence on the anode panel side facing these group of field emission elements. And a body region 121 (one red light emitting unit phosphor region, one green light emitting unit phosphor region, or one blue light emitting unit phosphor region). In the display area, such sub-pixels are arranged on the order of several hundred thousand to several million, for example. One pixel (one pixel) is composed of three sub-pixels.

  The anode electrode 130 is composed of an assembly of anode electrode units 131 covering the unit phosphor region 121. Gaps 132A and 132B are provided between the anode electrode units 131. The gap 132A is provided in the portion of the substrate 120 where the unit phosphor region 121 is not formed, and the gap 132B is formed so as to be located on the top surface of the partition wall 123 or straddling the partition wall 123. ing. A resistor layer 133 is formed between the anode electrode unit 131 and the anode electrode unit 131. More specifically, the resistor layer 133 is formed so as to cross the gaps 132A and 132B and straddle between the adjacent anode electrode units 131. The resistor layer 133 is composed of a resistor thin film made of, for example, silicon carbide (SiC), and is formed by a sputtering method.

  The size of the anode electrode unit 131 is such that the anode electrode unit 131 is locally generated by the energy generated by the discharge generated between the anode electrode unit 131 and the field emission device (more specifically, the gate electrode 13 or the cathode electrode 11). That does not evaporate (more specifically, a size corresponding to one subpixel in the anode electrode unit 131 by the energy generated by the discharge generated between the anode electrode unit 131 and the gate electrode 13 or the cathode electrode 11). This is the size that does not evaporate. 10 shows a 4 × 4 anode electrode unit 131 in order to simplify the drawing. In a schematic partial sectional view, one anode electrode unit 131 includes a plurality of unit phosphor regions. In practice, the anode electrode unit 131 has a size covering the unit phosphor region, that is, a size corresponding to one subpixel.

The anode electrode unit 131 </ b> A constituting one side of the anode electrode 130 is connected to the anode electrode control circuit 53 via the power feeding unit 140. A resistor R ₀ is usually disposed between the anode electrode control circuit 53 and the power feeding unit 140 to prevent overcurrent and discharge. Here, the power feeding unit 140 includes a power feeding unit 141 connected in series via the power feeding resistor layer 143. A gap 142A is provided between the power supply unit 141 and the power supply unit 141, and the power supply unit resistor layer 143 is disposed on the gap 142A so as to straddle between the power supply unit 141 and the power supply unit 141. Is formed. The power feeding unit 141 is also made of, for example, an aluminum thin film. A gap 142B is provided between the anode electrode unit 131A that constitutes one side of the anode electrode 130 and the power feeding unit 141, and the anode electrode unit 131A that constitutes one side of the anode electrode 130 and the power feeding unit 141 Are connected via a resistance member 134. The resistance member 134 is formed on the gap 142 </ b> B based on a chemical vapor deposition method (CVD method) so as to straddle between the anode electrode unit 131 and the power supply unit 141.

  In the display device disclosed in Japanese Patent Laid-Open No. 2004-158232, the anode electrode is divided into anode electrode units 131 having a smaller area instead of forming the anode electrode over almost the entire effective area. Thus, the capacitance between the anode electrode unit 131 and the cold cathode field emission device can be reduced. As a result, the occurrence of discharge can be reduced, and the occurrence of damage to the anode electrode and the cold cathode field emission device due to the discharge can be effectively reduced.

JP 2004-158232 A

  Thus, in the display device disclosed in Japanese Patent Application Laid-Open No. 2004-158232, the occurrence of discharge can be reduced. However, in order to form an anode electrode unit or the like, a complicated process for patterning a conductive material layer or the like is required. In addition, when patterning the conductive material layer or the like, it is difficult to avoid generation of minute foreign matters. Generally, a minute foreign substance in the display device triggers an unexpected discharge. Insufficient removal of foreign matter caused by patterning to form an anode electrode unit or the like will increase unexpected discharge caused by the foreign matter.

  Accordingly, an object of the present invention is to provide a flat display capable of effectively reducing the occurrence of damage to the anode electrode and cold cathode field emission device due to discharge without the need for forming an anode electrode unit or the like. To provide an apparatus.

In order to achieve the above object, a flat display device of the present invention comprises:
A flat panel display device in which a cathode panel provided with a plurality of electron emission regions and an anode panel provided with a phosphor region and an anode electrode are joined at the peripheral edge thereof.
The anode panel
(A) substrate,
(B) a phosphor region formed on the display region of the substrate;
(C) a light reflecting layer formed on the phosphor region, and
(D) an anode electrode formed on the light reflecting layer and covering the display area;
With
(A) The light reflecting layer is made of an insulating material,
(B) The anode electrode is made of a resistive material.

  In the flat display device of the present invention, the light reflection layer made of an insulating material is formed on the phosphor region, and the anode electrode made of a resistance material covers the display region and is formed on the light reflection layer. ing. When a trigger discharge occurs between the anode electrode and the cold cathode field emission device, the discharge is stored in the capacitance formed between the inner surface of the anode panel (anode electrode) and the inner surface of the cathode panel (for example, the gate electrode). The electrostatic energy flows as a current through the discharge site and tries to grow the discharge. That is, the electrostatic energy stored in the anode electrode is transmitted as a discharge current through the anode electrode (flows through the anode electrode) and tends to flow toward the discharge location. According to the present invention, since the anode electrode and the light reflection layer are each made of a resistance material and an insulating material, the magnitude of the discharge current flowing through the anode electrode is suppressed. This suppresses the growth of the discharge and hence the energy generated by the discharge, and reduces the occurrence of damage to the anode electrode and the cold cathode field emission device due to the discharge. A part of the light emitted from the phosphor region and traveling toward the cathode panel is returned to the anode panel by the light reflecting layer made of an insulating material. Thereby, the light emission efficiency of the display device can be improved in the same manner as the configuration using the conventional anode electrode that also functions as a reflective film. The light reflection layer is securely held on the anode panel by the anode electrode formed on the light reflection layer and covering the display area. Further, although depending on the light absorption rate of the resistance material constituting the anode electrode, at least part of the light traveling from the light reflection layer toward the cathode panel is shielded by the anode electrode. Thereby, contrast deterioration of the display image due to unnecessary light leakage to the cathode panel side is suppressed.

In the flat display device of the present invention, it is preferable that the anode current corresponding to the luminance of the image flows through the anode electrode without any trouble during normal operation. Accordingly, the sheet resistance value of the anode electrode has no hindrance to the supply of the anode current during the normal operation of the flat display device, and when a discharge occurs between the anode electrode and the cold cathode field emission device, It is desirable that the discharge current flowing through the anode electrode be in a range where the magnitude of the discharge current can be sufficiently suppressed. Examples of the sheet resistance value of the anode electrode include 1 × 10 ⁴ Ω / □ to 2 × 10 ⁵ Ω / □, preferably 2 × 10 ⁴ Ω / □ to 1 × 10 ⁵ Ω / □.

  In the present invention including the above preferred embodiments and configurations, the phosphor region is composed of a plurality of unit phosphor regions arranged in a matrix, and a light absorption layer is formed on the substrate between adjacent unit phosphor regions. The anode electrode may be formed so as to cover the light absorption layer. In this configuration, the light reflection layer may be formed only on the unit phosphor region, or may be formed on the unit phosphor region and the light absorption layer. The light absorption layer may be directly covered with the anode electrode, or may be indirectly covered with another layer (for example, a partition wall described later) or the like. The light absorption layer may be planarly formed on the substrate or may be three-dimensionally formed. Further, a grid-like partition wall surrounding each unit phosphor region may be provided on the light absorption layer. By providing the partition walls, electrons recoiled from the unit phosphor region or secondary electrons emitted from the unit phosphor region enter another unit phosphor region, and so-called optical crosstalk (color turbidity) occurs. Occurrence can be prevented. A partition may be formed on the light absorption layer, and the anode electrode may be configured to cover the light absorption layer via the partition, or the anode electrode may be formed to cover the light absorption layer. Then, a structure in which a partition wall is formed on the portion of the anode electrode corresponding to the light absorption layer may be employed.

  In the present invention including the above preferred form and configuration, when an anode voltage is applied to the anode electrode made of a resistance material, for example, it is provided on a substrate constituting the anode panel and is passed through a power feeding portion made of a conductive material. An anode voltage can be applied. What is necessary is just to set suitably the shape of a power supply part, the material which comprises a power supply part, the order of formation of a power supply part and an anode electrode, etc. according to the design of a flat type display apparatus. A power feeding unit surrounding the display area is provided on the substrate, and the power feeding unit and the anode electrode may be stacked. The power supply unit may be any shape that substantially surrounds the display area, and does not necessarily have to be a closed shape. According to this configuration, since the anode voltage is uniformly applied around the anode electrode, the potential uniformity over the entire anode electrode can be improved. The power feeding unit can be formed by a method appropriately selected depending on a material to be used, such as a combination of a spin coating method and a lift-off method, various printing methods, a lithography technique, and the like. Examples of the constituent material of the power feeding unit include metal materials such as molybdenum (Mo), aluminum (Al), chromium (Cr), and tungsten (W), and glass paste containing conductive particles.

In the flat display device of the present invention including the preferred embodiments and configurations described above (hereinafter, these may be collectively referred to simply as the present invention), the insulating material constituting the light reflecting layer As such, materials that exist stably under vacuum conditions and heating conditions can be widely used. For example, the light reflecting layer can be formed using an insulating compound. If the light reflecting layer becomes thicker than necessary, the charging of the phosphor region becomes difficult to flow to the anode electrode. Therefore, it is preferable that the light reflection layer has a sheet resistance value that ensures the function of the light reflection layer and that the charging of the phosphor region flows without trouble to the anode electrode. Examples of the sheet resistance value of the formed light reflecting layer include 1 × 10 ⁶ Ω / □ to 1 × 10 ¹⁰ Ω / □. Examples of the insulating compound constituting the light reflecting layer include metal oxides such as titanium oxide, aluminum oxide, zinc oxide, and magnesium oxide; metal sulfides such as WS _x ; metal salts such as barium sulfate, calcium carbonate, and calcium phosphate. Can be mentioned. In order to effectively reflect the light from the phosphor region (unit phosphor region), the average particle size is about 1 × 10 ⁻⁷ m (about 0.1 μm) to about 4 × 10 ⁻⁷ m (about 0.1 μm). 4 μm), more preferably white light reflecting layer by particles of insulating material in the range of about 1.5 × 10 ⁻⁷ m (about 0.15 μm) to about 3 × 10 ⁻⁷ m (about 0.3 μm) It is desirable to configure. When the light reflecting layer is formed by a coating method or the like, a coating such as silicic acid or alumina may be applied to the surface of the insulating material particles in order to suppress aggregation. The light reflecting layer can be formed by, for example, a combination of a spin coating method and a lift-off method in which particles of an insulating material are dispersed in polyvinyl alcohol (PVA) resin and water. In addition to the polyvinyl alcohol (PVA) resin, an acrylic resin, an acrylic emulsion, or the like may be used. The light reflecting layer can be formed by a method appropriately selected depending on the material to be used, such as various printing methods and lithography techniques. From the viewpoint of the luminous efficiency of the display device, the phosphor region side of the light reflecting layer is preferably formed on a smooth surface. For example, a resin layer is provided on the phosphor region, a light reflection layer is formed on the resin layer, and then the resin layer is removed by a heat treatment or the like, so that the phosphor region side of the light reflection layer is made smooth. Can be formed. Examples of the material constituting the resin layer include lacquer or polyvinyl alcohol (PVA) aqueous solution. Here, the lacquer is a kind of varnish in a broad sense, which is a cellulose derivative, generally a mixture of nitrocellulose as a main component dissolved in a volatile solvent such as a lower fatty acid ester, or other synthetic polymer. This includes urethane lacquers, acrylic lacquers, chromium compounds and manganese compounds used. In the case of an aqueous polyvinyl alcohol solution, a solution obtained by mixing a glycol solvent and glycerin in a dilute aqueous solution to adjust the drying speed, and a solution added with a chromium compound or a manganese compound are included. As a method for forming the resin layer, a screen printing method; a metal mask printing method; a coating method using a roll coater, a spray coater, or a transfer method; a lacquer float method (resin on the water surface with a substrate placed in water stored in a water tank) A method of depositing a resin layer on a substrate by forming a layer and draining water can be exemplified. The resin layer is removed by performing heat treatment. More specifically, for example, the resin layer may be burned (decomposed and removed) by performing heat treatment at a temperature at which the resin layer burns.

As the resistance material constituting the anode electrode, materials that exist stably under vacuum conditions and heating conditions can be widely used. For example, a semimetal such as graphite (carbon), an oxide, a boride, a carbide, a sulfide, and a nitride can be used. For example, compounds containing a metalloid element ₂ such as a semi-metal and MoSe such as _{graphite, Cr 2 O 3, Nd 2} O 3, La x Ba 2-x CuO 4, La x Ba 2-x CuO 4, La x Y Oxides such as _1-x CrO ₃ , borides such as AlB ₂ and TiB ₂ , carbides such as silicon carbide (SiC) and tungsten carbide, sulfides such as MoS ₂ and WS ₂ , and nitriding such as BN and SiN And the like. Qualitatively, the greater the light absorption rate of the resistive material, the less light leakage to the cathode panel side by the light reflecting layer. Further, when the leaked light is reflected on the cathode panel side and re-entered on the anode panel side, a phenomenon is observed in which the vicinity of the spacer is relatively dark and the portion away from the spacer is relatively bright. The greater the light absorptance of the resistive material, the less re-incidence of the leaked light to the anode panel side. Therefore, it is preferable to select a resistance material having a large light absorption rate from the viewpoint of reducing light leakage. As a method for forming the anode electrode, for example, vapor deposition methods such as electron beam vapor deposition method and hot filament vapor deposition method, various physical vapor deposition methods (PVD method) such as sputtering method, ion plating method and laser ablation method; Vapor phase growth method (CVD method); various printing methods; lift-off method; sol-gel method.

  The electrons emitted from the electron emission region pass through the anode electrode and the light reflection layer and reach the phosphor region (unit phosphor region). The energy of electrons is reduced by colliding with substances constituting them when they pass through the anode electrode and the light reflection layer. Qualitatively, the light emission of the phosphor region becomes weaker as the anode electrode and the light reflection layer become thicker. On the other hand, qualitatively, when the light reflection layer becomes thicker, the reflection efficiency of the light reflection layer is improved. Therefore, the thickness of the reflective layer may be determined in consideration of the degree of decrease in electron energy and the degree of improvement in the reflection efficiency of the light reflective layer. Examples of the average thickness of the light reflection layer on the phosphor region include 0.5 μm to 10 μm, preferably 1 μm to 4 μm. Moreover, as an average thickness of the anode electrode on a light reflection layer, 0.1 micrometer-0.6 micrometer, Preferably 0.2 micrometer-0.4 micrometer can be illustrated.

  The light absorption layer provided on the substrate between the adjacent unit phosphor regions functions as a so-called black matrix, and improves the contrast of the display image. As the material constituting the light absorption layer, it is preferable to select a material that absorbs 80% or more of light from the unit phosphor region. In addition, if a path with low resistance is formed by contact between the light absorption layer and the anode electrode made of a resistance material, the effect of suppressing the discharge current is impaired. Therefore, it is preferable that the light absorption layer is made of a high resistance material or an insulating material. Examples of such a material include a metal oxide (for example, chromium oxide), a metal nitride (for example, chromium nitride), a heat resistant organic resin, a glass paste, and a glass paste containing a black pigment. The light absorption layer depends on the material used, for example, a combination of vacuum deposition method, sputtering method and etching method, a combination of vacuum deposition method, sputtering method, spin coating method and lift-off method, various printing methods, lithography technology, etc. Thus, it can be formed by an appropriately selected method.

  The flat display device of the present invention can be a cold cathode field emission display device having an electron emission region composed of one or more cold cathode field emission devices (hereinafter abbreviated as field emission devices). Alternatively, a flat display device having an electron emission region composed of a metal / insulating film / metal type element (also referred to as an MIM element), and a flat type having an electron emission region composed of a surface conduction type electron emission element It can also be a display device.

When the flat display device is a cold cathode field emission display device, the electron emission region for emitting electrons includes one or a plurality of field emission elements,
Each field emission device
(A) a strip-shaped cathode electrode formed on the support and extending in the first direction;
(B) an insulating layer formed on the cathode electrode and the support;
(C) a strip-shaped gate electrode formed on the insulating layer and extending in a second direction different from the first direction;
(D) an opening provided in a portion of the gate electrode and the insulating layer located in an overlapping portion where the cathode electrode and the gate electrode overlap, and the cathode electrode exposed at the bottom; and
(E) an electron emission portion provided on the cathode electrode exposed at the bottom of the opening,
Consists of.

  Here, the type of the field emission device is not particularly limited, and a Spindt-type field emission device (a field emission device in which a conical electron emission portion is provided on the cathode electrode located at the bottom of the opening) or a flat type Type field emission device (a field emission device in which a substantially planar electron emission portion is provided on the cathode electrode located at the bottom of the opening).

  In the cathode panel, the projection image of the cathode electrode and the projection image of the gate electrode are orthogonal to each other, that is, the first direction and the second direction are orthogonal to each other in the structure of the cold cathode field emission display device. It is preferable from the viewpoint of simplification. An overlapping region where the cathode electrode and the gate electrode overlap corresponds to an electron emission region, and the electron emission region is arranged in a two-dimensional matrix in the effective region of the cathode panel. The first direction may be the X direction, the second direction may be the Y direction, the first direction may be the Y direction, and the second direction may be the X direction.

  In the cold cathode field emission display, a strong electric field generated by a voltage applied to the cathode electrode and the gate electrode is applied to the electron emission portion, and as a result, electrons are emitted from the electron emission portion by the quantum tunnel effect. The electrons are attracted to the anode panel by the anode electrode provided on the anode panel, and collide with the phosphor region (unit phosphor region). As a result of the collision of electrons with the phosphor region, the phosphor region emits light and can be recognized as an image.

In the cold cathode field emission display, the cathode electrode is connected to the cathode electrode control circuit, the gate electrode is connected to the gate electrode control circuit, and the anode electrode is connected to the anode electrode control circuit. Note that these control circuits can be constituted by known circuits. During actual operation, the voltage (anode voltage) V _A applied to the anode electrode from the anode electrode control circuit is normally constant, and can be, for example, 5 to 15 kilovolts. Alternatively, when the distance between the anode panel and the cathode panel is d ₀ (where 0.5 mm ≦ d ₀ ≦ 10 mm), the value of V _A / d ₀ (unit: kilovolt / mm) is 0. It is desirable to satisfy 5 or more and 20 or less, preferably 1 or more and 10 or less, and more preferably 4 or more and 8 or less. In actual operation of the cold cathode field emission display, the voltage modulation method can be adopted as the gradation control method for the voltage V _C applied to the cathode electrode and the voltage V _G applied to the gate electrode.

A field emission device can be generally manufactured by the following method.
(1) forming a cathode electrode on a support;
(2) forming an insulating layer on the entire surface (on the support and the cathode electrode);
(3) forming a gate electrode on the insulating layer;
(4) forming an opening in a portion of the gate electrode and the insulating layer in a region where the cathode electrode and the gate electrode overlap, and exposing the cathode electrode at the bottom of the opening;
(5) A step of forming an electron emission portion on the cathode electrode located at the bottom of the opening.

Alternatively, the field emission device can be manufactured by the following method.
(1) forming a cathode electrode on a support;
(2) forming an electron emission portion on the cathode electrode;
(3) forming an insulating layer on the entire surface (on the support and the electron emission portion or on the support, the cathode electrode and the electron emission portion);
(4) forming a gate electrode on the insulating layer;
(5) A step of forming an opening in a portion of the gate electrode and the insulating layer in the overlapping region of the cathode electrode and the gate electrode, and exposing the electron emission portion at the bottom of the opening.

  The field emission device may be provided with a focusing electrode. That is, for example, a field emission element in which an interlayer insulating layer is further provided on the gate electrode and the insulating layer, and a focusing electrode is provided on the interlayer insulating layer, or a focusing electrode is provided above the gate electrode. It can also be a field emission device. Here, the focusing electrode is an electrode for converging the trajectory of emitted electrons that are emitted from the opening and directed toward the anode electrode, thereby improving the luminance and preventing optical crosstalk between adjacent pixels. It is. In a so-called high voltage type cold cathode field emission display, the potential difference between the anode electrode and the cathode electrode is on the order of several kilovolts or more and the distance between the anode electrode and the cathode electrode is relatively long. The electrode is particularly effective. A relative negative voltage (for example, 0 volts) is applied to the focusing electrode from the focusing electrode control circuit. The focusing electrode does not necessarily have to be individually formed so as to surround each of the electron emission portion or the electron emission region provided in the overlapping region where the cathode electrode and the gate electrode overlap, for example, the electron emission portion or The electron emission region may be extended along a predetermined arrangement direction, or the electron emission portion or the electron emission region may be surrounded by one focusing electrode (that is, the focusing electrode may be a cold cathode field electron). It may be a thin sheet-like structure covering the entire effective area, which is the central display area that performs a practical function as an emission display device), thereby providing a plurality of electron emission areas or electron emission areas. A common convergence effect can be exerted.

  In the Spindt-type field emission device, the material constituting the electron emission portion is molybdenum, molybdenum alloy, tungsten, tungsten alloy, titanium, titanium alloy, niobium, niobium alloy, tantalum, tantalum alloy, chromium, chromium alloy, and And at least one material selected from the group consisting of silicon (polysilicon and amorphous silicon) containing impurities. The electron emission portion of the Spindt-type field emission device can be formed by various PVD methods such as sputtering and vacuum deposition, and various CVD methods.

In the flat field emission device, it is preferable that the material constituting the electron emission portion is composed of a material having a work function Φ smaller than that of the material constituting the cathode electrode. What is necessary is just to determine based on the work function of the material which comprises a cathode electrode, the electric potential difference between a gate electrode and a cathode electrode, the magnitude | size of the emission electron current density requested | required, etc. Alternatively, the material constituting the electron emission portion may be appropriately selected from materials in which the secondary electron gain δ of the material is larger than the secondary electron gain δ of the conductive material constituting the cathode electrode. In the flat type field emission device, carbon, more specifically, amorphous diamond or graphite, a carbon nanotube structure (carbon nanotube and / or graphite nanofiber), as a particularly preferable constituent material of the electron emission portion, Examples thereof include ZnO whiskers, MgO whiskers, SnO ₂ whiskers, MnO whiskers, Y ₂ O ₃ whiskers, NiO whiskers, ITO whiskers, In ₂ O ₃ whiskers, and Al ₂ O ₃ whiskers. In addition, the material which comprises an electron emission part does not necessarily need to be provided with electroconductivity.

The constituent materials of the cathode electrode, gate electrode, and focusing electrode are aluminum (Al), tungsten (W), niobium (Nb), tantalum (Ta), molybdenum (Mo), chromium (Cr), copper (Cu), gold ( Metals such as Au), silver (Ag), titanium (Ti), nickel (Ni), cobalt (Co), zirconium (Zr), iron (Fe), platinum (Pt), zinc (Zn); these metal elements Alloys (eg, MoW) or compounds (eg, nitrides such as TiN, silicides such as WSi ₂ , MoSi ₂ , TiSi ₂ , TaSi ₂ ); semiconductors such as silicon (Si); carbon thin films such as diamond; ITO ( Examples thereof include conductive metal oxides such as indium oxide-tin oxide, indium oxide, and zinc oxide. In addition, as a method for forming these electrodes, for example, a vapor deposition method such as an electron beam vapor deposition method or a hot filament vapor deposition method, a sputtering method, a combination of a CVD method, an ion plating method, and an etching method; Various printing methods such as a metal mask printing method; plating methods (electroplating method and electroless plating method); lift-off method; laser ablation method; sol-gel method and the like can be mentioned. According to various printing methods and plating methods, for example, a strip-like cathode electrode or gate electrode can be directly formed.

As a material for constituting the insulating layer and the interlayer insulating _{layer, SiO 2, BPSG, PSG,} BSG, AsSG, PbSG, SiON, SOG ( spin on glass), low-melting glass, SiO ₂ based materials such glass paste; insulating resin such as polyimide Can be used alone or in appropriate combination. For forming the insulating layer or the interlayer insulating layer, a known process such as a CVD method, a coating method, a sputtering method, or various printing methods can be used.

  Planar shape of the first opening (opening formed in the gate electrode) or the second opening (opening formed in the insulating layer) (shape when the opening is cut in a virtual plane parallel to the support surface) ) Can be any shape such as a circle, an ellipse, a rectangle, a polygon, a rounded rectangle, a rounded polygon. The formation of the first opening can be performed by, for example, anisotropic etching, isotropic etching, a combination of anisotropic etching and isotropic etching, or, depending on the method of forming the gate electrode, The first opening can also be formed directly. The second opening can also be formed by, for example, anisotropic etching, isotropic etching, or a combination of anisotropic etching and isotropic etching.

  In the field emission device, depending on the structure of the field emission device, one electron emission portion may exist in one opening, or a plurality of electron emission portions may exist in one opening. In addition, a plurality of first openings are provided in the gate electrode, one second opening communicating with the first opening is provided in the insulating layer, and one or more are provided in one second opening provided in the insulating layer. There may be an electron emission portion.

In the field emission device, a resistor film may be provided between the cathode electrode and the electron emission portion. By providing the resistor film, the operation of the field emission device can be stabilized and the electron emission characteristics can be made uniform. Materials constituting the resistor film include carbon-based materials such as SiC and SiCN, semiconductor materials such as SiN and amorphous silicon, refractory metal oxides such as ruthenium oxide (RuO ₂ ), tantalum oxide, and tantalum nitride, and refractory metal nitriding. Things can be exemplified. Examples of the method for forming the resistor film include a sputtering method, a CVD method, and various printing methods. The electrical resistance value per one electron emitting portion is approximately 1 × 10 ⁶ to 1 × 10 ¹¹ Ω, preferably several gigaΩ.

As a support constituting the cathode panel or as a substrate constituting the anode panel, a glass substrate, a glass substrate with an insulating film formed on the surface, a quartz substrate, a quartz substrate with an insulating film formed on the surface, and a surface Examples of the semiconductor substrate include an insulating film. From the viewpoint of reducing manufacturing costs, it is preferable to use a glass substrate or a glass substrate having an insulating film formed on the surface. As a glass substrate, high strain point glass, soda glass (Na ₂ O · CaO · SiO ₂ ), borosilicate glass (Na ₂ O · B ₂ O ₃ · SiO ₂ ), forsterite (2MgO · SiO ₂ ), lead glass (Na ₂ O · PbO · SiO ₂ ) and alkali-free glass can be exemplified.

  The phosphor region may be composed of monochromatic phosphor particles or may be composed of three primary color phosphor particles. When the phosphor region is composed of a plurality of unit phosphor regions arranged in a matrix, the unit phosphor region is arranged in a dot form. Specifically, when the flat display device performs color display, examples of the arrangement and arrangement of the unit phosphor regions include a delta arrangement, a stripe arrangement, a diagonal arrangement, and a rectangle arrangement. That is, one row of the unit phosphor regions arranged in a straight line includes a row in which all the red light emitting unit phosphor regions are occupied, a row in which the green light emitting unit phosphor region is occupied, and a blue light emitting unit phosphor. It may be composed of a column occupied by a region, or may be composed of a column in which a red light emitting unit phosphor region, a green light emitting unit phosphor region, and a blue light emitting unit phosphor region are sequentially arranged. . Here, the unit phosphor region is defined as a phosphor region that generates one bright spot on the anode panel. One pixel (one pixel) is composed of a set of one red light emitting unit phosphor region, one green light emitting unit phosphor region, and one blue light emitting unit phosphor region. It is composed of one unit phosphor region (one red light-emitting unit phosphor region, one green light-emitting unit phosphor region, or one blue light-emitting unit phosphor region).

  The unit phosphor region uses a luminescent crystal particle composition prepared from luminescent crystal particles (for example, phosphor particles having a particle size of about 2 to 10 nm), for example, a red photosensitive luminescent crystal particle composition. The product (red phosphor slurry) is coated on the entire surface, exposed and developed to form a red light emitting unit phosphor region, and then the green photosensitive luminescent crystal particle composition (green phosphor slurry) is coated on the entire surface. The green light-emitting unit phosphor region is formed by coating, exposing and developing, and further, a blue photosensitive luminescent crystal particle composition (blue phosphor slurry) is coated on the entire surface, exposed and developed. The blue light emitting unit phosphor region can be formed by a method. Alternatively, each unit phosphor region may be formed by sequentially applying a red light emitting phosphor slurry, a green light emitting phosphor slurry, and a blue light emitting phosphor slurry, and then sequentially exposing and developing each phosphor slurry. Each unit phosphor region may be formed by a screen printing method, an ink jet method, a float coating method, a sedimentation coating method, a phosphor film transfer method, or the like. The average thickness of the unit phosphor region on the substrate is not limited, but is 3 μm to 20 μm, preferably 5 μm to 10 μm.

The phosphor material constituting the luminescent crystal particles can be appropriately selected from conventionally known phosphor materials. In the case of color display, a phosphor material whose color purity is close to the three primary colors specified by NTSC, white balance is achieved when the three primary colors are mixed, the afterglow time is short, and the afterglow time of the three primary colors is almost equal. It is preferable to combine them. As phosphor materials constituting the red light emitting unit phosphor region, (Y ₂ O ₃ : Eu), (Y ₂ O ₂ S: Eu), (Y ₃ Al ₅ O ₁₂ : Eu), (Y ₂ SiO ₅ : Eu) and (Zn ₃ (PO ₄ ) ₂ : Mn) can be exemplified, and among them, (Y ₂ O ₃ : Eu) and (Y ₂ O ₂ S: Eu) are preferably used. Further, as the phosphor material constituting the green light emitting unit phosphor region, (ZnSiO ₂ : Mn), (Sr ₄ Si ₃ O ₈ Cl ₄ : Eu), (ZnS: Cu, Al), (ZnS: Cu, Au) , Al), [(Zn, Cd) S: Cu, Al], (Y ₃ Al ₅ O ₁₂ : Tb), (Y ₂ SiO ₅ : Tb), [Y ₃ (Al, Ga) ₅ O ₁₂ : Tb ], (ZnBaO ₄ : Mn), (GbBO ₃ : Tb), (Sr ₆ SiO ₃ Cl ₃ : Eu), (BaMgAl ₁₄ O ₂₃ : Mn), (ScBO ₃ : Tb), (Zn ₂ SiO ₄ : Mn) ), (ZnO: Zn), (Gd ₂ O ₂ S: Tb), and (ZnGa ₂ O ₄ : Mn), among which (ZnS: Cu, Al), (ZnS: Cu, Au) , Al), [(Zn, Cd) S: Cu, Al], (Y ₃ Al ₅ O ₁₂ : Tb), [Y ₃ (Al, Ga) ₅ O ₁₂ : Tb] or (Y ₂ SiO ₅ : Tb) is preferably used. Further, as phosphor materials constituting the blue light emitting unit phosphor region, (Y ₂ SiO ₅ : Ce), (CaWO ₄ : Pb), CaWO ₄ , YP _0.85 V _0.15 O ₄ , (BaMgAl ₁₄ O ₂₃ : Eu) ), (Sr ₂ P ₂ O ₇ : Eu), (Sr ₂ P ₂ O ₇ : Sn), (ZnS: Ag, Al), (ZnS: Ag), ZnMgO, and ZnGaO ₄ . Among these, it is preferable to use (ZnS: Ag) or (ZnS: Ag, Al).

  Electrons recoiled from the unit phosphor region or secondary electrons emitted from the unit phosphor region are incident on other unit phosphor regions to prevent so-called optical crosstalk (color turbidity). In order to prevent collision of electrons recoiled from the unit phosphor region or secondary electrons emitted from the unit phosphor region with other unit phosphor regions. Is preferred.

  Examples of the partition wall forming method include a screen printing method, a dry film method, a photosensitive method, a casting method, and a sandblast forming method. Here, in the screen printing method, an opening is formed in a portion of the screen corresponding to a portion where a partition is to be formed, and the partition forming material on the screen is passed through the opening using a squeegee, and the partition is formed on the substrate. In this method, after the formation material layer is formed, the partition wall formation material layer is fired. The dry film method is a method of laminating a photosensitive film on a substrate, removing the photosensitive film at the part where the partition wall is to be formed by exposure and development, embedding the partition wall forming material in the opening generated by the removal, and baking. . The photosensitive film is burned and removed by baking, and the partition wall-forming material embedded in the openings remains to form partition walls. The photosensitive method is a method in which a barrier rib-forming material layer having photosensitivity is formed on a substrate, the barrier rib-forming material layer is patterned by exposure and development, and then fired (cured). The casting method (embossing molding method) refers to a method for forming a partition wall forming material layer by extruding a partition wall forming material layer made of a paste-like organic material or inorganic material onto a substrate from a mold (cast). In this method, the partition wall forming material layer is fired. The sand blast forming method is, for example, forming a partition wall forming material layer on a substrate using a screen printing or metal mask printing method, a roll coater, a doctor blade, a nozzle discharge type coater, etc. In this method, the part of the partition wall forming material layer to be covered is covered with a mask layer, and then the exposed part of the partition wall forming material layer is removed by sandblasting. After the partition wall is formed, the partition wall may be polished to flatten the top surface of the partition wall.

  Rectangular shape, circular shape, elliptical shape, oval shape as a planar shape (corresponding to the inner contour line of the projected image of the side face of the partition wall, which is a kind of opening region) surrounding the unit phosphor region in the lattice-shaped partition wall And a triangular shape, a pentagonal or more polygonal shape, a rounded triangular shape, a rounded rectangular shape, a rounded polygon, and the like. By arranging these planar shapes (planar shapes of the opening regions) in a two-dimensional matrix, a grid-like partition is formed. This two-dimensional matrix-like arrangement may be arranged, for example, like a cross or like a zigzag.

Examples of the partition wall forming material include photosensitive polyimide resin, SiO ₂ and low melting point glass paste. A protective layer (for example, made of SiO ₂ , SiON, or AlN) is provided on the surface (top surface and side surface) of the partition wall to prevent an electron beam from colliding with the partition wall and releasing gas from the partition wall. It may be formed.

  In the present invention, the spacer can be made of, for example, ceramics or glass. When the spacer is made of ceramics, the ceramics include mullite, alumina, barium titanate, lead zirconate titanate, zirconia, cordiolite, borosilicate barium, iron silicate, glass ceramic materials, titanium oxide and chromium oxide. Examples thereof include iron oxide, vanadium oxide, and nickel oxide added. In this case, the spacer can be manufactured by forming a so-called green sheet, firing the green sheet, and cutting the green sheet fired product. In addition, it is preferable to chamfer the end portion of the spacer to remove the protruding portion and the like. For example, the spacer may be fixed by being sandwiched between partition walls provided in the anode panel, or, for example, a spacer holding portion may be formed on the anode panel and / or the cathode panel and fixed by the spacer holding portion. do it.

An antistatic film may be provided on the side surface of the spacer. The material constituting the antistatic film preferably has a secondary electron emission coefficient close to 1, and as the material constituting the antistatic film, a semimetal such as graphite, an oxide, a boride, a carbide, a sulfide, and A nitride or the like can be used. For example, a compound containing a semimetal such as graphite and a semimetal element such as MoSe ₂ , CrO _x , CrAl _x O _y , manganese oxide, Nd ₂ O ₃ , La _x Ba _2−x CuO ₄ , La _x Ba _2−x CuO ₄ , oxides such as La _x Y _1-x CrO ₃ , borides such as AlB ₂ and TiB ₂ , carbides such as SiC, sulfides such as MoS ₂ and WS ₂ , and compounds of tungsten nitride and germanium nitride In addition, nitrides such as BN, TiN, and AlN can be used, and further, for example, materials described in JP-T-2004-500688 can be used. The antistatic film may be composed of a single type of material, may be composed of a plurality of types of materials, may be a single layer structure, or may be a multilayer structure. May be. The antistatic film can be formed based on a known method such as a sputtering method, a vacuum deposition method, a CVD method, or the like.

The cathode panel and the anode panel are joined at the peripheral edge. The joining may be performed using an adhesive layer, or a rod-like or frame-like (frame-like) material made of an insulating rigid material such as glass or ceramics. The frame body and the adhesive layer may be used in combination. When using a frame and an adhesive layer together, the opposing distance between the cathode panel and the anode panel is set longer than when only the adhesive layer is used by appropriately selecting the height of the frame. Is possible. The material constituting the adhesive layer is generally a frit glass such as B ₂ O ₃ —PbO-based frit glass or SiO ₂ —B ₂ O ₃ —PbO-based frit glass, but has a melting point of about 120 to 400 ° C. These so-called low melting point metal materials may be used. Such low melting point metal materials include In (indium: melting point 157 ° C.); indium-gold based low melting point alloy; Sn ₈₀ Ag ₂₀ (melting point 220 to 370 ° C.), Sn ₉₅ Cu ₅ (melting point 227 to 370 ° C.) C) tin (Sn) type high temperature solder such as Pb _97.5 Ag _2.5 (melting point 304 ° C.), Pb _94.5 Ag _5.5 (melting point 304 to 365 ° C.), Pb _97.5 Ag _1.5 Sn _1.0 (melting point 309 ° C.), etc. Lead (Pb) high temperature solder; zinc (Zn) high temperature solder such as Zn ₉₅ Al ₅ (melting point 380 ° C.); Sn ₅ Pb ₉₅ (melting point 300 to 314 ° C.), Sn ₂ Pb ₉₈ (melting point 316 to 322) Tin-lead standard solder such as ° C); brazing material such as Au ₈₈ Ga ₁₂ (melting point 381 ° C) (the above subscripts all represent atomic%).

  When joining the three of the cathode panel, the anode panel and the frame, the three may be joined at the same time, or in the first stage, either the cathode panel or the anode panel and the frame are joined, In the second stage, the other of the cathode panel or the anode panel and the frame may be joined. When the three-party simultaneous bonding or the second-stage bonding is performed in a high vacuum atmosphere, the space surrounded by the cathode panel, the anode panel, the frame, and the adhesive layer becomes a vacuum simultaneously with the bonding. Alternatively, the space surrounded by the cathode panel, the anode panel, the frame body, and the adhesive layer can be exhausted and vacuumed after the completion of the joining of the three parties. When exhausting after joining, the pressure of the atmosphere at the time of joining may be normal pressure / depressurized, and the gas constituting the atmosphere may be air, or nitrogen gas or group 0 of the periodic table An inert gas containing a gas belonging to (for example, Ar gas) may be used.

  When exhaust is performed, the exhaust can be performed through an exhaust pipe connected in advance to the cathode panel and / or the anode panel. The exhaust pipe is typically a glass pipe, or a metal or alloy having a low coefficient of thermal expansion [for example, an iron (Fe) alloy containing 42 wt% nickel (Ni), 42 wt% nickel (Ni), An iron (Fe) alloy containing 6% by weight of chromium (Cr)], and an ineffective region of the cathode panel and / or the anode panel (a central portion that performs a practical function as a flat display device) After the space has reached a predetermined degree of vacuum, it is joined to the periphery of the penetrating part provided in the frame surrounding the effective area, which is the display area, using the frit glass or the low melting point metal material. It can be sealed by thermal fusion, or it can be sealed by crimping. In addition, if the whole flat display device is once heated and then cooled before sealing, it is preferable because residual gas can be released into the space, and this residual gas can be removed out of the space by exhaust. .

  In the flat display device of the present invention, since the anode electrode and the light reflection layer are each made of a resistance material and an insulating material, the magnitude of the discharge current flowing through the anode electrode is suppressed. Thereby, the energy generated by the discharge can be suppressed without requiring formation of an anode electrode unit or the like. Therefore, it is possible to provide a flat display device that can effectively reduce the occurrence of damage due to discharge. In addition, the light reflection layer made of an insulating material improves the light emission efficiency of the display device, similarly to the configuration using the conventional anode electrode that also functions as a reflection film. Then, at least a part of the light traveling from the light reflection layer to the cathode panel side is shielded by the anode electrode, and contrast deterioration of the display image due to unnecessary light leakage to the cathode panel side can be suppressed.

  Hereinafter, the present invention will be described based on examples with reference to the drawings.

  Example 1 relates to a flat display device of the present invention.

  FIG. 1 shows a schematic partial end view of a flat display device according to the first embodiment or another embodiment described later (hereinafter sometimes referred to as the first embodiment or the like). More specifically, the flat display device of Example 1 or the like includes a cold cathode field emission display (hereinafter abbreviated as a display device).

In the display device in Example 1 or the like, a cathode panel CP provided with a plurality of electron emission regions EA and an anode panel AP provided with a phosphor region 21 and an anode electrode 30 are joined at their peripheral portions. A display device. Here, the space between the cathode panel CP and the anode panel AP is in a vacuum state (pressure: for example, 10 ⁻³ Pa or less). A schematic exploded perspective view of a part of the anode panel AP and the cathode panel CP when the cathode panel CP and the anode panel AP are disassembled is basically the same as that shown in FIG.

In Example 1 or the like, the field emission device constituting the electron emission region EA is constituted by, for example, a Spindt type field emission device. As shown in FIG. 1, the Spindt-type field emission device is
(A) a cathode electrode 11 formed on the support 10;
(B) an insulating layer 12 formed on the support 10 and the cathode electrode 11;
(C) a gate electrode 13 formed on the insulating layer 12;
(D) the opening 14 provided in the gate electrode 13 and the insulating layer 12 (the first opening 14A provided in the gate electrode 13 and the second opening 14B provided in the insulating layer 12), and
(E) a conical electron emission portion 15 formed on the cathode electrode 11 located at the bottom of the opening 14;
It is composed of

  In the cathode panel CP, the cathode electrode 11 has a strip shape extending in the first direction (see the Y direction in the figure), and the gate electrode 13 has a second direction (see the X direction in FIG. 1) different from the first direction. ). The cathode electrode 11 and the gate electrode 13 are each formed in a strip shape in a direction in which the projected images of both the electrodes 11 and 13 are orthogonal to each other. A plurality of field emission elements are provided in the electron emission area EA corresponding to one subpixel.

As shown in FIG. 1, the anode panel AP is
(A) substrate,
(B) a phosphor region formed on the display region of the substrate;
(C) a light reflecting layer formed on the phosphor region, and
(D) an anode electrode formed on the light reflecting layer and covering the display area;
With
(A) The light reflecting layer is made of an insulating material,
(B) The anode electrode is made of a resistance material.

In the display device of Example 1 or the like, the phosphor region 21 has a plurality of unit phosphor regions 22 arranged in a matrix (more specifically, a red light emitting unit phosphor region 22R, a green light emitting unit phosphor). A region 22G and a blue light-emitting unit phosphor region 22B). The phosphor region 21 is a rectangular region as a whole and corresponds to the display region of the display device. A light absorption layer (black matrix) 23 is formed on the substrate 20 between the adjacent unit phosphor regions 22. One pixel includes a red light emitting unit phosphor region 22R, a green light emitting unit phosphor region 22G, and a blue light emitting unit phosphor region 22B. The unit phosphor region 22 has a rectangular shape. Furthermore, a spacer (not shown) made of alumina (Al ₂ O ₃ , purity 99.8 wt%) is disposed between the cathode panel CP and the anode panel AP.

In the display device of Example 1 or the like, the light reflecting layer 31 made of titanium oxide is formed on each unit phosphor region 22. An anode electrode 30 made of SiC is formed on the light reflection layer 31 and the light absorption layer 23 so as to cover the display region. The sheet resistance value of the anode electrode 30 is 1 × 10 ⁴ Ω / □ or more in consideration of the supply of the anode current during the normal operation of the display device and the fact that the magnitude of the discharge current flowing through the anode electrode can be sufficiently suppressed. It is desirable that it is 2 × 10 ⁵ Ω / □, preferably 2 × 10 ⁴ Ω / □ to 1 × 10 ⁵ Ω / □. Specifically, for example, 8 × 10 ⁴ Ω / □. Examples of the sheet resistance value of the light reflecting layer include 1 × 10 ⁶ Ω / □ to 1 × 10 ¹⁰ Ω / □.

  In order to apply an anode voltage to the anode electrode 30, a power feeding unit 40 made of a conductive material is provided on the substrate 20. The power feeding unit 40 is provided so as to surround the display area, and the power feeding unit 40 and the anode electrode 30 are laminated. In the display device of Example 1, the power feeding unit 40 was formed on the anode electrode 30 by printing a glass paste containing conductive particles in a predetermined pattern. An arrangement state of the unit phosphor region 22, the anode electrode 30, and the power feeding unit 40 in the anode panel AP is schematically shown in FIG. In FIG. 2, the unit phosphor region 22, the anode electrode 30, and the power feeding unit 40 are hatched to clearly show the components of the anode panel AP. Further, the number and arrangement state of the unit phosphor regions 22 in FIG. 2 are for explanation, and are different from an actual display device.

In the display device of Example 1, the cathode electrode 11 is connected to the cathode electrode control circuit 51, the gate electrode 13 is connected to the gate electrode control circuit 52, and the anode electrode 30 is connected to the anode electrode control circuit 53 via the power feeding unit 40. It is connected. These control circuits can be constituted by known circuits. During actual operation of the display device, the output voltage v _A of the anode electrode control circuit 53 is normally constant, and can be, for example, 5 kilovolts to 15 kilovolts. On the other hand, regarding the voltage v _C applied to the cathode electrode 11 and the voltage v _G applied to the gate electrode 13 during actual operation of the display device,
(1) A method in which the voltage v _C applied to the cathode electrode 11 is constant and the voltage v _G applied to the gate electrode 13 is changed. (2) The voltage v _C applied to the cathode electrode 11 is changed and applied to the gate electrode 13. the voltage v _G changing the voltage v _C is applied to the method (3) a cathode electrode 11, fixed to, and may employ any voltage v method in which _G is also changed to be applied to the gate electrode 13.

During actual operation of the display device, a relatively negative voltage is applied to the cathode electrode 11 from the cathode electrode control circuit 51, a relatively positive voltage is applied to the gate electrode 13 from the gate electrode control circuit 52, and the anode electrode 30 A positive voltage higher than that of the gate electrode 13 is applied from the anode electrode control circuit 53. When performing display in such a display device, for example, a scanning signal is input to the cathode electrode 11 from the cathode electrode control circuit 51, and a video signal is input to the gate electrode 13 from the gate electrode control circuit 52. Note that a video signal may be input to the cathode electrode 11 from the cathode electrode control circuit 51, and a scanning signal may be input to the gate electrode 13 from the gate electrode control circuit 52. Electrons are emitted from the electron emission portion 15 based on the quantum tunnel effect due to an electric field generated when a voltage is applied between the cathode electrode 11 and the gate electrode 13, and the electrons are attracted to the anode electrode 30. The light passes through the light absorption layer 31 and collides with the unit phosphor region 22. As a result, the unit phosphor region 22 is excited to emit light, and a desired image can be obtained. That is, the operation of this display device is basically controlled by the voltage v _G applied to the gate electrode 13 and the voltage v _C applied to the cathode electrode 11.

  Hereinafter, Example 1 will be described with reference to FIGS. 3A to 3C and FIGS. 4A to 4C which are schematic partial end views of the substrate 20 and the like constituting the anode panel AP. A method for manufacturing the anode panel of the display device and a method for manufacturing the display device will be described.

[Step-100]
First, the lattice-like light absorption layer 23 is formed on the substrate 20 (see FIG. 3A). Specifically, a low melting glass paste colored black with a metal oxide such as cobalt oxide is printed on the substrate 20 by a screen printing method, and then the low melting glass paste is baked to form a lattice-shaped light. The absorption layer 23 was formed. In addition, the thickness of the light absorption layer 23 was about 8 μm, and the size of the opening region of the light absorption layer 23 (region in which the unit phosphor region was formed) was about 200 μm × 60 μm.

[Step-110]
Next, the unit phosphor region 22 is formed on the portion of the substrate 20 surrounded by the light absorption layer 23 (see FIG. 3B). Specifically, to form the red light emitting unit phosphor region 22R, for example, a red light emitting phosphor in which red light emitting phosphor particles are dispersed in, for example, polyvinyl alcohol (PVA) resin and water, and ammonium bichromate is further added. After applying the slurry to the entire surface, the red light emitting phosphor slurry is dried. Thereafter, the portion of the red light emitting phosphor slurry where the red light emitting unit phosphor region 22R is to be formed is irradiated with ultraviolet rays through a mask having a predetermined opening to expose the red light emitting phosphor slurry. The thickness of the red light emitting unit phosphor region 22R was about 8 μm. Thereafter, the red light emitting phosphor slurry is developed to form the red light emitting unit phosphor region 22R. Hereinafter, the green emission unit phosphor region 22G is formed by performing the same treatment on the green emission phosphor slurry, and further the blue emission unit phosphor by performing the same treatment on the blue emission phosphor slurry. Region 22B is formed. Thus, the structure shown in FIG. 3B can be obtained. The method of forming the unit phosphor region is not limited to the method described above, and after sequentially applying the red light emitting phosphor slurry, the green light emitting phosphor slurry, and the blue light emitting phosphor slurry, each phosphor slurry is sequentially exposed, Each unit phosphor region may be formed by development, or each unit phosphor region may be formed by a screen printing method or the like.

[Step-120]
Thereafter, a resin layer 32 is formed on each unit phosphor region 22 (see FIG. 3C). Specifically, a metal mask or mesh screen mask having an opening that substantially matches the formation pattern of the resin layer 32 is prepared, for example, an acrylic lacquer is placed on the mask, and the acrylic lacquer on the mask is passed through the opening with a squeegee. Thus, the resin layer 32 can be formed based on a metal mask printing method or a screen printing method such as printing on each unit phosphor region 22. Thereafter, the substrate 20 is carried into a drying furnace and dried at a predetermined temperature. The drying temperature of the resin layer 32 is preferably in the range of 50 ° C. to 90 ° C., for example, and the drying time of the resin layer 32 is preferably in the range of several minutes to several tens of minutes, for example. Of course, as the drying temperature increases and decreases, the drying time decreases.

[Step-130]
Next, a light reflecting layer 31 made of an insulating material is formed on each unit phosphor region 22 (see FIG. 4A). Specifically, for example, titanium oxide particles are dispersed in polyvinyl alcohol (PVA) resin and water, and a titanium oxide slurry to which ammonium bichromate is added is applied to the entire surface, and then the titanium oxide slurry is dried. In order to ensure sufficient light reflectivity of the light reflecting layer, a titanium oxide slurry having an average particle diameter of about 2.5 × 10 ⁻⁷ m (about 0.25 μm) and titanium oxide of about 50% by volume is prepared. did. Thereafter, similarly to the above-described exposure of the phosphor slurry, the portion of the titanium oxide slurry on which the light reflecting layer 31 is to be formed is irradiated with ultraviolet rays to expose the titanium oxide slurry. The thickness of the formed light reflecting layer 31 was about 3 μm. Thereafter, by developing the titanium oxide slurry, the light reflecting layer 31 made of an insulating material formed on each unit phosphor region 22 can be obtained. The formation method of a light reflection layer is not limited to the method demonstrated above, You may form by the screen printing method etc.

[Step-140]
Next, an anode electrode 30 made of a resistive material is formed so as to cover the display region and be formed on the light reflecting layer 31 (see FIG. 4B). Specifically, the anode electrode 30 made of SiC is formed so as to cover the light absorption layer 23 by various vapor deposition methods or sputtering methods. The thickness of the formed anode electrode 30 was about 0.3 μm.

[Step-150]
Thereafter, the resin layer 32 is removed by heat treatment. Specifically, the resin layer 32 is baked at about 400 ° C. (see FIG. 4C). By this baking treatment, the resin layer 32 is burned and burned out, and the light reflecting layer 31 is left on each unit phosphor region 22. The unit phosphor region 22 side of the light reflecting layer 31 is formed on a smooth surface by following the surface of the resin layer 32. The gas generated by the combustion of the resin layer 32 is discharged to the outside through, for example, the fine holes of the light reflecting layer 31 and the anode electrode 30. Since the hole is fine, it does not affect the structural strength of the light reflecting layer 31 and the anode electrode 30.

[Step-160]
Thereafter, a glass paste containing conductive particles is printed in a predetermined pattern on the anode electrode 30 so as to surround the display region, and this is baked. As a result, the power feeding unit 40 and the anode electrode 30 are stacked.

  Through the above steps, the anode panel AP can be completed.

[Step-170]
A cathode panel CP on which field emission elements are formed is prepared. A method of manufacturing the field emission device will be described next. Then, the display device is assembled. Specifically, for example, a spacer (not shown) is attached to a spacer holding portion (not shown) provided in the effective area of the anode panel AP so that the unit phosphor region 22 and the field emission element face each other. An anode panel AP and a cathode panel CP are arranged, and the anode panel AP and the cathode panel CP (more specifically, the substrate 20 and the support 10) are made of a ceramic or glass frame having a height of about 1 mm. It joins in a peripheral part via 25. At the time of joining, frit glass is applied to the joining part between the frame 25 and the anode panel AP and the joining part between the frame 25 and the cathode panel CP, and the anode panel AP, the cathode panel CP, and the frame 25 are pasted. In addition, the frit glass is dried by preliminary baking, and then main baking is performed at about 450 ° C. for 10 to 30 minutes. Thereafter, the space surrounded by the anode panel AP, the cathode panel CP, the frame 25 and the frit glass (not shown) is exhausted through a through hole (not shown) and a tip tube (not shown), When the pressure reaches about 10 ⁻⁴ Pa, the tip tube is sealed by heating and melting. In this way, the space surrounded by the anode panel AP, the cathode panel CP, and the frame body 25 can be evacuated. Alternatively, for example, the frame 25, the anode panel AP, and the cathode panel CP may be bonded together in a high vacuum atmosphere. Alternatively, depending on the structure of the display device, the anode panel AP and the cathode panel CP may be bonded together by using only an adhesive layer without a frame. Thereafter, wiring connection with necessary external circuits is performed, and the display device is completed.

  Hereinafter, a method for manufacturing a Spindt-type field emission device will be described with reference to FIGS. 5A and 5B and FIGS. 6A and 6B which are schematic partial end views of the support 10 and the like constituting the cathode panel. A description will be given with reference to B).

  This Spindt-type field emission device can be basically obtained by a method of forming the conical electron emission portion 15 by vertical vapor deposition of a metal material. That is, the vapor deposition particles are perpendicularly incident on the first opening 14A provided in the gate electrode 13, but use the shielding effect by the overhanging deposit formed near the opening end of the first opening 14A. Thus, the amount of vapor deposition particles reaching the bottom of the second opening 14B is gradually reduced, and the electron emission portion 15 that is a conical deposit is formed in a self-aligning manner. Here, a method for forming the separation layer 16 in advance on the gate electrode 13 and the insulating layer 12 in order to facilitate removal of unnecessary overhanging deposits will be described. In the drawing for explaining the method of manufacturing the field emission device, only one electron emission portion is shown.

[Step-A0]
First, a cathode electrode conductive material layer made of, for example, polysilicon is formed on the support 10 made of, for example, a glass substrate by a plasma CVD method, and then the cathode electrode conductive material layer is formed based on a lithography technique and a dry etching technique. Is patterned to form a strip-like cathode electrode 11. Thereafter, an insulating layer 12 made of SiO _{2 is} formed on the entire surface by a CVD method.

[Step-A1]
Next, a gate electrode conductive material layer (for example, a TiN layer) is formed on the insulating layer 12 by sputtering, and then the gate electrode conductive material layer is patterned by a lithography technique and a dry etching technique. Thus, the strip-shaped gate electrode 13 can be obtained. The strip-shaped cathode electrode 11 extends in the left-right direction in the drawing, and the strip-shaped gate electrode 13 extends in the direction perpendicular to the drawing.

  The gate electrode 13 is formed by a well-known thin film such as a PVD method such as a vacuum evaporation method, a CVD method, a plating method such as an electroplating method or an electroless plating method, a screen printing method, a laser ablation method, a sol-gel method, a lift-off method. You may form by the combination of formation and an etching technique as needed. According to the screen printing method or the plating method, for example, a strip-shaped gate electrode can be directly formed.

[Step-A2]
Thereafter, a resist layer is formed again, the first opening 14A is formed in the gate electrode 13 by etching, the second opening 14B is formed in the insulating layer, and the cathode electrode 11 is formed at the bottom of the second opening 14B. After the exposure, the resist layer is removed. Thus, the structure shown in FIG. 5A can be obtained.

[Step-A3]
Next, nickel (Ni) is obliquely vapor-deposited on the insulating layer 12 including the gate electrode 13 while rotating the support 10 to form a release layer 16 (see FIG. 5B). At this time, by selecting a sufficiently large incident angle of the vapor deposition particles with respect to the normal of the support 10 (for example, an incident angle of 65 to 85 degrees), nickel is hardly deposited on the bottom of the second opening 14B. A release layer 16 can be formed on the gate electrode 13 and the insulating layer 12. The release layer 16 protrudes in a bowl shape from the opening end of the first opening 14A, whereby the diameter of the first opening 14A is substantially reduced.

[Step-A4]
Next, for example, molybdenum (Mo) is vertically deposited as an electrically conductive material on the entire surface (incident angle: 3 to 10 degrees). At this time, as shown in FIG. 6A, as the conductive member layer 17 having an overhang shape grows on the release layer 16, the substantial diameter of the first opening 14A is gradually reduced. The vapor deposition particles that contribute to the deposition at the bottom of the second opening 14B are gradually limited to those that pass near the center of the first opening 14A. As a result, a conical deposit is formed at the bottom of the second opening 14 </ b> B, and this conical deposit becomes the electron emission portion 15.

[Step-A5]
Thereafter, as shown in FIG. 6B, the peeling layer 16 is peeled off from the surfaces of the gate electrode 13 and the insulating layer 12 by a lift-off method, and the conductive member layer 17 above the gate electrode 13 and the insulating layer 12 is selected. To remove. Thus, a cathode panel in which a plurality of Spindt type field emission devices are formed can be obtained.

  In the display device according to the first embodiment, the anode electrode and the light reflection layer are each made of a resistance material and an insulating material, so that the magnitude of the discharge current flowing through the anode electrode is suppressed. As a result, the energy generated by the discharge is also suppressed, and the occurrence of damage to the anode electrode or the cold cathode field emission device due to the discharge is reduced. A part of the light emitted from the phosphor region and traveling toward the cathode panel is returned to the anode panel by the light reflecting layer made of an insulating material. Thereby, the light emission efficiency of the display device can be improved in the same manner as the configuration using the conventional anode electrode that also functions as a reflective film. Moreover, in Example 1, the adhesiveness of the light reflection layer 31 and the unit fluorescent substance region 22 falls by combustion of a resin layer. However, the light reflection layer is securely held on the anode panel by the anode electrode formed on the light reflection layer and covering the display area. In the experiment using the plurality of display devices of Example 1, during the operation in which about 10 kV was applied between the anode panel and the cathode panel, the anode was subjected to laser-excited forced discharge conditions at 20 positions on each panel. The phosphor did not fall off in the phosphor region of the panel, and the damage occurrence rate to the electron emission region in the cathode panel was suppressed to about 14%. On the other hand, in the display device of the comparative example having the same configuration as that of the display device of Example 1 except that the anode electrode is formed by vapor deposition of aluminum, the operation in which about 10 kV is applied between the anode panel and the cathode panel. After the discharge was generated inside, the dropping of the phosphor in the phosphor region and the damage in the electron emission region were observed extensively and in a chained manner in all places.

  Example 2 relates to a flat display device of the present invention. The display device of Example 1 is different in that the structure of the light absorption layer constituting the anode panel is different.

  Since the configuration and structure of the display device, the anode panel AP, and the cathode panel, the configuration and the structure of the power feeding unit, the field emission device, and the like can be the same as those in the first embodiment, their detailed description is omitted.

  Hereinafter, with reference to FIGS. 7A to 7C and FIGS. 8A to 8C, a method for manufacturing an anode panel for a flat display device of Example 2, and a flat display device manufacture A method will be described.

[Step-200]
First, in the same manner as in [Step-100] of Example 1, a lattice-like light absorption layer 23 is formed on the substrate 20 (see FIG. 7A). Specifically, a black photosensitive polyimide resin was used as a material, and a lattice-shaped light absorption layer 23 was formed by a lithography technique. The thickness of the light absorption layer 23 was approximately 0.3 μm, and the size of the opening region of the light absorption layer 23 (region in which the unit phosphor region 22 was formed) was approximately 60 μm × 200 μm.

[Step-210]
Next, the unit phosphor region 22 is formed on the portion of the substrate 20 surrounded by the light absorption layer 23 in the same manner as in [Step-110] of Example 1 (see FIG. 7B).

[Step-220]
Thereafter, the resin layer 32 is formed on the unit phosphor region 22 in the same manner as in [Step-120] in Example 1 (see FIG. 7C).

[Step-230]
Next, in the same manner as in [Step-130] of Example 1, a light reflecting layer 31 made of an insulating material and formed on the unit phosphor region 22 is formed (see FIG. 7A).

[Step-240]
Thereafter, in the same manner as in [Step-140] in Example 1, the anode electrode 30 made of a resistive material is formed to cover the display area and formed on the light reflecting layer 31 (see FIG. 8B). .

[Step-250]
Next, in the same manner as in [Step-150] of Example 1, the resin layer 32 is removed by heat treatment.

  Thereafter, the power feeding unit 40 is formed in the same manner as in [Step-160] of the first embodiment. Through the above steps, the anode panel AP can be completed. Next, the display device of Example 2 can be completed in the same manner as [Step-170] of Example 1.

  As mentioned above, although this invention was demonstrated based on the preferable Example, this invention is not limited to these Examples. The configurations and structures of the anode panel and cathode panel, anode electrode, power supply unit, display device and field emission device described in the embodiments are examples, and can be changed as appropriate. The anode panel, cathode panel, anode electrode, The method for manufacturing the power feeding unit, the display device, and the field emission element is also an example, and can be changed as appropriate. Furthermore, various materials used in the manufacture of the anode panel and the cathode panel are also examples, and can be changed as appropriate. The display device has been described by taking color display as an example, but it may also be a single color display.

  For example, in Example 1, after [Step-100], a grid-like partition wall 24 surrounding each unit phosphor region 22 is provided on the light absorption layer 23, and then [Step-110] to [Step-170]. ] To complete the anode panel AP. FIG. 9 is a schematic partial end view of an anode panel for a flat display device when the partition wall 24 is provided.

  In the embodiment, the power feeding unit 40 is formed after the anode electrode 30 is formed, but the present invention is not limited to this. After forming the power feeding unit 40, the anode electrode 30 made of a resistive material may be formed. In this case, the anode electrode may be formed so that the portion of the power feeding unit 40 connected to the anode electrode control circuit 53 is exposed.

  In the embodiment, the planar shape of the portion surrounding the unit phosphor region 22 in the light absorption layer 23 is a rectangular shape, but it may be a circular shape, a hexagonal shape, a triangular shape, an elliptical shape, an oval shape, or the like. The shape may be a pentagon or more polygonal shape, a rounded triangular shape, a rounded rectangular shape, a rounded polygon, or the like. In addition, a lattice-shaped light absorption layer is formed by arranging these planar shapes in a two-dimensional matrix. However, the two-dimensional matrix may be arranged in a grid pattern, for example. It may be arranged in a zigzag manner.

  In the field emission device, a mode in which one electron emission portion corresponds to one opening has been described. However, depending on the structure of the field emission device, a mode in which a plurality of electron emission portions correspond to one opening. Alternatively, one electron emission portion may correspond to a plurality of openings. Alternatively, a plurality of first openings are provided in the gate electrode, a plurality of second openings connected to the plurality of first openings in the insulating layer are provided, and one or a plurality of electron emission portions are provided. You can also.

  In the field emission device, an interlayer insulating layer may be further provided on the gate electrode 13 and the insulating layer 12, and a focusing electrode may be provided on the interlayer insulating layer.

The electron emission portion can also be constituted by a field emission device commonly called a surface conduction type field emission device. This surface conduction type field emission device is formed on a support made of glass, for example, tin oxide (SnO ₂ ), gold (Au), indium oxide (In ₂ O ₃ ) / tin oxide (SnO ₂ ), carbon, palladium oxide ( A pair of counter electrodes made of a conductive material such as (PdO), having a small area, and arranged at a predetermined interval (gap) are formed in a matrix. A carbon thin film is formed so as to straddle the counter electrode. A row direction wiring or a column direction wiring (first electrode) is connected to one counter electrode of the pair of counter electrodes, and a column direction wiring or a row direction wiring (first electrode) is connected to the other counter electrode of the pair of counter electrodes. (Second electrode) is connected. By applying a voltage from the first electrode and the second electrode to the pair of counter electrodes, an electric field is applied to the carbon thin films facing each other across the gap, and electrons are emitted from the carbon thin film. By causing the electrons to collide with the phosphor region on the anode panel, the phosphor region is excited to emit light, and a desired image can be obtained. Alternatively, the electron emission source can be constituted by a metal / insulating film / metal type element.

FIG. 1 is a schematic partial end view of a flat display device of Example 1 or the like. FIG. 2 is a plan view schematically showing the arrangement state of the unit phosphor region, the anode electrode, and the power feeding unit in the anode panel. 3A to 3C are schematic partial end views of a substrate and the like for explaining a method for manufacturing an anode panel constituting the flat display device of Example 1. FIG. FIGS. 4A to 4C are schematic partial views of a substrate and the like for explaining a method of manufacturing an anode panel constituting the flat display device of Example 1, following FIG. 3C. It is an end view. 5A and 5B are schematic partial end views of a support and the like for explaining a method for manufacturing a Spindt-type cold cathode field emission device. 6 (A) and 6 (B) are schematic partial end views of a support and the like for explaining the manufacturing method of the Spindt-type cold cathode field emission device following FIG. 5 (B). . 7A to 7C are schematic partial end views of a substrate and the like for explaining a method of manufacturing an anode panel constituting the flat display device of Example 2. FIG. FIGS. 8A to 8C are schematic partial views of a substrate and the like for explaining a manufacturing method of an anode panel constituting the flat display device of Example 2 following FIG. 7C. It is an end view. FIG. 9 is a schematic partial end view of the anode panel when the partition walls are provided. FIG. 10 is a schematic plan view of an anode electrode in a conventional cold cathode field emission display disclosed in Japanese Patent Application Laid-Open No. 2004-158232. FIGS. 11A, 11B, and 11C are respectively the lines AA, BB, and BB of the anode panel in the conventional cold cathode field emission display shown in FIG. It is a typical partial end view along line CC. FIG. 12 is a schematic partial end view of a cold cathode field emission display. FIG. 13 is a schematic partial perspective view of a cathode panel of a cold cathode field emission display.

Explanation of symbols

AP ... anode panel, CP ... cathode panel, EA ... electron emission region, 10 ... support, 11 ... cathode electrode, 12 ... insulating layer, 13 ... gate electrode, DESCRIPTION OF SYMBOLS 14 ... Opening part, 14A ... 1st opening part, 14B ... 2nd opening part, 15 ... Electron emission part, 16 ... Release layer, 20 ... Substrate, 21 ... Phosphor region, 22, 22R, 22G, 22B ... Unit phosphor region, 23 ... Light absorption layer (black matrix), 24 ... Partition, 25 ... Frame, 30 ... Anode Electrode, 31... Light reflecting layer, 32... Resin layer, 40... Power feeding part, 51... Cathode electrode control circuit, 52. 120 ... substrate, 121 ... unit phosphor region, 122 ... light absorption Layer (black matrix), 123 ... partition wall, 130 ... anode electrode, 131, 131A ... anode electrode unit, 132A, 132B ... gap, 133 ... resistor layer, 134 ... Resistance member, 140... Power feeding unit, 141... Power feeding unit, 142A, 142B... Gap, 143.

Claims (5)

A flat panel display device in which a cathode panel provided with a plurality of electron emission regions and an anode panel provided with a phosphor region and an anode electrode are joined at the peripheral edge thereof.
The anode panel
(A) substrate,
(B) a phosphor region formed on the display region of the substrate;
(C) a light reflecting layer formed on the phosphor region, and
(D) an anode electrode formed on the light reflecting layer and covering the display area;
With
(A) The light reflecting layer is made of an insulating material,
(B) The flat display device, wherein the anode electrode is made of a resistance material. 2. The flat display device according to claim 1, wherein a sheet resistance value of the anode electrode is 1 × 10 ⁴ Ω / □ to 2 × 10 ⁵ Ω / □. 3. The flat display device according to claim 2, wherein the sheet resistance value of the anode electrode is 2 × 10 ⁴ Ω / □ to 1 × 10 ⁵ Ω / □.   The phosphor region is composed of a plurality of unit phosphor regions arranged in a matrix. A light absorption layer is formed on a substrate between adjacent unit phosphor regions, and the anode electrode covers the light absorption layer. The flat display device according to claim 1, wherein the flat display device is formed.   The flat display device according to claim 1, wherein a power supply unit surrounding the display area is provided on the substrate, and the power supply unit and the anode electrode are stacked.

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