JP2007109481A - Flat display device, spacer, and inspection method of spacer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spacer used in a flat display device which can reduce the relative luminance variation of a pixel along the spacer, a flat display device incorporating this spacer, and an inspection method of the spacer. <P>SOLUTION: This spacer 140, which is used in a flat display device, is arranged between a cathode panel and an anode panel. The spacer 140 is constructed of a spacer substrate 140A, a first electrode 140B, a second electrode 140C, and an electrode for measuring resistance value 140D of a belt shape. When the resistance value at impressing of a voltage of 1 [kV] between the first electrode and the second electrode is R<SB>12</SB>, and the resistance value at impressing of a voltage of (H<SB>2</SB>/(H<SB>1</SB>+H<SB>2</SB>))×1 [kV], between the second electrode and the electrode for measuring resistance value, is R<SB>23</SB>, 0.95×(H<SB>2</SB>/(H<SB>1</SB>+H<SB>2</SB>))≤R<SB>23</SB>/R<SB>12</SB>≤1.05×(H<SB>2</SB>/(H<SB>1</SB>+H<SB>2</SB>)) is satisfied. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a spacer used in a flat display device that displays information such as characters and images, a flat display device incorporating such a spacer, and a method for inspecting such a spacer.

  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). Development of a flat display device incorporating an electron emission source is also in progress. Here, cold cathode field emission devices, metal / insulating film / metal type devices (also called MIM devices) and surface conduction type electron emission devices are known as electron emission sources, and these electron emission sources are incorporated. The flat display device is attracting attention from the viewpoint of high resolution, high luminance color display, and low power consumption.

  2. Description of the Related Art 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 electron emission element as an electron emission source, is generally arranged in a two-dimensional matrix. A cathode panel having an electron emission region corresponding to each pixel (in the case of color display, each subpixel), and an anode having a phosphor layer that emits light when excited by collision with electrons emitted from the electron emission region The panel has a configuration in which the panel is disposed to face each other through a space in a vacuum state. 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.

  As an example, a conceptual partial end view of a display device having a Spindt-type field emission device is shown in FIG. 4, and a schematic view of a part of the cathode panel CP and the anode panel AP when the cathode panel CP and the anode panel AP are disassembled. A simple exploded perspective view is shown in FIG. The Spindt-type field emission device constituting this display device is formed on a cathode electrode 11 formed on a support 10, an insulating layer 12 formed on the support 10 and the cathode electrode 11, and an insulating layer 12. The gate electrode 13 and 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 a conical electron emission portion 15 formed on the cathode electrode 11 located at the bottom of the opening 14.

  In this display device, the cathode electrode 11 extends in the first direction (the Y direction in FIGS. 4 and 5). The gate electrode 13 extends in a second direction (X direction in FIGS. 4 and 5) different from the first direction. 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 has a phosphor layer 22 (specifically, a red light-emitting phosphor layer 22R, a green light-emitting phosphor layer 22G, and a blue light-emitting phosphor layer 22B) having a predetermined pattern on the substrate 20. The phosphor layer 22 is formed and covered with the anode electrode 24. Between these phosphor layers 22, a light absorbing layer (black matrix) 23 made of a light absorbing material such as carbon is embedded to prevent display image color turbidity and optical crosstalk. ing. In the figure, reference numeral 21 represents a partition, reference numeral 40 represents a plate-shaped spacer, reference numeral 25 represents a spacer holding portion, reference numeral 26 represents a frame, and reference numeral 16 represents a focusing electrode. Reference numeral 17 denotes an interlayer insulating layer. In FIG. 5, illustration of the partition walls, the spacers, the spacer holding portion, the focusing electrode, and the interlayer insulating layer is omitted.

  The anode electrode 24 has a function of preventing charging of the phosphor layer 22 in addition to a function as a reflection film that reflects light emitted from the phosphor layer 22. Further, the barrier rib 21 is configured such that electrons recoiled from the phosphor layer 22 or secondary electrons emitted from the phosphor layer 22 (hereinafter, these electrons are collectively referred to as backscattered electrons) are used as other fluorescence. It has a function of preventing so-called optical crosstalk (color turbidity) from colliding with the body layer 22.

  One subpixel is configured by an electron emission area EA on the cathode panel CP side and a phosphor layer 22 on the anode panel side facing the electron emission area EA. In the case of a color display device, one pixel (one pixel) is composed of a set of one red-emitting phosphor layer, one green-emitting phosphor layer, and one blue-emitting phosphor layer. . In the effective area, such pixels are arranged on the order of hundreds of thousands to millions, for example.

Then, the anode panel AP and the cathode panel CP are arranged so that the electron emission area EA and the phosphor layer 22 face each other, joined at the peripheral portion via the frame body 26, and then exhausted and sealed. Thus, a display device can be manufactured. A space surrounded by the anode panel AP, the cathode panel CP, and the frame body 26 is in a high vacuum (for example, 1 × 10 ⁻³ Pa or less).

  Therefore, if the spacer 40 is not disposed between the anode panel AP and the cathode panel CP, the display device is damaged by the atmospheric pressure. The spacer 40 includes a spacer base 40A, a first electrode 40B, and a second electrode 40C. The spacer base material 40A includes a first end face portion facing the anode panel AP, a second end face portion facing the cathode panel CP, and a pair of side face portions, and the first electrode 40B is a first end face of the spacer base material 40A. The second electrode 40C is provided on the second end surface portion of the spacer base material 40A. If necessary, an antistatic film is provided on the side surface of the spacer base material 40A.

  A relatively negative voltage is applied to the cathode electrode 11 from the cathode electrode control circuit 31, a relatively positive voltage is applied to the gate electrode 13 from the gate electrode control circuit 32, and a focusing electrode control circuit ( A relatively negative voltage (for example, 0 volts) is applied from an anode electrode control circuit 33, and a higher positive voltage than that of the gate electrode 13 is applied to the anode electrode 24. 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 31, and a video signal is input to the gate electrode 13 from the gate electrode control circuit 32. Alternatively, a video signal is input from the cathode electrode control circuit 31 to the cathode electrode 11, and a scanning signal is input from the gate electrode control circuit 32 to the gate electrode 13. Electrons are emitted from the electron emitter 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 24. It passes and collides with the phosphor layer 22. As a result, the phosphor layer 22 is excited to emit light, and a desired image can be obtained. That is, the operation of the cold cathode field emission display is basically controlled by the voltage applied to the gate electrode 13 and the voltage applied to the cathode electrode 11.

  The spacer base 40A constituting the spacer 40 is made of a high resistance rigid material such as mullite, alumina, ceramic such as barium titanate, or glass. Both ends of the spacer 40 are in contact with the anode electrode 24 and the convergence electrode 16, respectively. Therefore, a potential difference (voltage) between the voltage applied to the anode electrode 24 and the voltage applied to the focusing electrode 16 is applied between both ends of the spacer 40. Depending on the type of the display device, the cathode side of the spacer is in contact with the gate electrode. In this case, a potential difference (voltage) between the voltage applied to the anode electrode and the voltage applied to the gate electrode is applied between both ends of the spacer. Therefore, the spacer 40 is basically required to have a high resistance so that an excessive current does not flow through the spacer 40. Further, as will be described later, the potential difference (voltage) at both end surfaces of the spacer 40 (between the first end surface portion and the second end surface portion of the spacer 40) needs to be divided equally between the both end surfaces of the spacer 40. There is. For this reason, the 1st electrode 40B and the 2nd electrode 40C are provided in the both end surface part of 40 A of spacer base materials, and a favorable electrical connection can be obtained in a spacer end surface part. For example, Patent Document 1 discloses a spacer having an electrode on an end surface portion.

  6A and 6B schematically show the trajectory of the electron beam in the pixel located in the vicinity of the spacer 40. FIG. In FIGS. 6A and 6B, the partition wall 21, the spacer holding portion 25, and the interlayer insulating layer 17 are not shown. As shown in FIG. 6A, when the specific resistance of the spacer base material 40 </ b> A is uniform, the voltage is equally divided between both ends of the spacer 40. Accordingly, the electric field becomes a parallel electric field also in the vicinity of the spacer 40, and the electrons emitted from the electron emission portion 15 go to a predetermined position on the phosphor layer 22. However, as shown in FIG. 6B, if the specific resistance of the spacer base material 40A is not uniform, the electric field is not uniform in the vicinity of the spacer 40, which affects the electron trajectory. That is, the electrons emitted from the electron emitter 15 do not collide with a predetermined position of the phosphor layer 22, and a relative luminance change occurs in the pixels along the spacer 40.

For example, when the spacer substrate is made of a ceramic material,
(A) Using ceramic powder as a dispersoid, adding a binder to prepare a slurry for green sheets,
(B) A green sheet is obtained from the slurry for the green sheet, and then
(C) firing the green sheet;
Thus, a ceramic material can be obtained. However, for example, insufficient stirring and mixing at the time of slurry preparation, non-uniform firing due to non-uniform temperature during green sheet firing, or oxidation / reduction due to non-uniform air flow during green sheet firing If the degree of is non-uniform, the specific resistance of the ceramic material becomes non-uniform. In general, it is difficult to completely eliminate non-uniform resistivity in the spacer base material.

  Therefore, it is known to adjust the electric field distribution in the vicinity of the spacer by providing an electrode on the side surface of the spacer base (see, for example, Patent Document 1 and Patent Document 2). Further, in the spacer in which the electrodes are provided on the end surface portion and the side surface portion of the spacer base material, the voltage is equally divided in the height direction of the spacer (the Z direction in FIGS. 4 to 6). In order to confirm indirectly, the resistance value between the electrode on one end face part and the electrode on the side face part and the resistance value between the electrode on the other end face part and the electrode on the side face part are measured, and the measurement is performed. It is also known to check whether or not a predetermined voltage division ratio is based on the result (see, for example, Patent Document 3).

US Pat. No. 5,859,502 JP 2002-108271 A JP-A-2005-93202

  However, in a spacer in which electrodes are provided on the end surface portion and the side surface portion of the spacer base material, the relative luminance change of the pixels along the spacer does not become a practical problem. What conditions should be satisfied for the position and width, the resistance value between the electrode on one end face and the electrode on the side face, and the resistance value between the electrode on the other end face and the side face electrode? Is unknown. Also, a specific evaluation method has been desired for the spacer inspection method.

  Accordingly, an object of the present invention is to provide a flat panel display device, a spacer, and a spacer inspection method capable of reducing a relative luminance change of pixels along the spacer.

  In order to achieve the above object, a flat panel display according to the present invention includes a cathode panel in which a plurality of electron emission sources that emit electrons are formed on a support, and a fluorescent light that collides with electrons emitted from the electron emission source. A body layer and an anode panel formed by forming an anode electrode on a substrate are joined at their peripheral portions, a spacer is disposed between the cathode panel and the anode panel, and the space is sandwiched between the cathode panel and the anode panel The present invention relates to a flat display device in which is held in a vacuum.

  In order to achieve the above object, the spacer of the present invention includes a cathode panel in which a plurality of electron emission sources that emit electrons are formed on a support, and a phosphor that collides with electrons emitted from the electron emission source. An anode panel having a layer and an anode electrode formed on a substrate is joined at the periphery thereof, and is used in a flat display device in which a space sandwiched between the cathode panel and the anode panel is maintained in a vacuum. The present invention relates to a spacer disposed between a panel and an anode panel.

  In addition, the spacer inspection method of the present invention for achieving the above-described object includes a cathode panel in which a plurality of electron emission sources that emit electrons are formed on a support, and an electron emitted from the electron emission source collides. Used in a flat panel display device in which a phosphor layer and an anode panel formed by forming an anode electrode on a substrate are joined at their peripheral portions and the space sandwiched between the cathode panel and the anode panel is maintained in a vacuum The present invention relates to a method for inspecting a spacer disposed between a cathode panel and an anode panel.

In the spacer constituting the flat display device of the present invention, the spacer of the present invention, or the spacer inspected by the spacer inspection method of the present invention,
The spacer includes a spacer base material, a first electrode, a second electrode, and a strip-shaped resistance measurement electrode. The spacer base material has a first end face portion facing the anode panel and a second end face facing the cathode panel. A first electrode is provided on the first end surface portion of the spacer base material, and a second electrode is provided on the second end surface portion of the spacer base material. The value measuring electrode includes a spacer base material such that the first edge on the first end face side extends in parallel with the first end face and the second edge on the second end face side extends in parallel with the second end face. Is provided on the side surface of one side of the.

And in the spacer constituting the flat display device of the present invention, or the spacer of the present invention,
The distance between the first end face and the first edge of the resistance measurement electrode is H ₁ , the distance between the second end face and the second edge of the resistance measurement electrode is H ₂ , and the resistance measurement electrode When the distance between the first edge and the second edge is H ₃ and the distance between the first end face and the second end face is H ₄ , 0.2 × H ₄ ≦ H ₁ ≦ 0.8 × H ₄ , 0.2 × H ₄ ≦ H ₂ ≦ 0.8 × H ₄ and 10 μm ≦ H ₃ ≦ 0.2 × H ₄
The resistance value when a voltage of 1 [kV] is applied between the first electrode and the second electrode is R ₁₂ , and the resistance value between the second electrode and the resistance value measuring electrode is (H ₂ / (H ₁ + H ₂ )) When a resistance value when a voltage of 1 [kV] is applied is R ₂₃ , 0.95 × (H ₂ / (H ₁ + H ₂ )) ≦ R ₂₃ / R ₁₂ ≦ 1.05 × ( H ₂ / (H ₁ + H ₂ )) is satisfied.

Further, in the spacer inspection method of the present invention,
The distance between the first end face and the first edge of the resistance measurement electrode is H ₁ , the distance between the second end face and the second edge of the resistance measurement electrode is H ₂ , and the resistance measurement electrode When the distance between the first edge and the second edge is H ₃ and the distance between the first end face and the second end face is H ₄ , 0.2 × H ₄ ≦ H ₁ ≦ 0.8 × H ₄ , 0.2 × H ₄ ≦ H ₂ ≦ 0.8 × H ₄ and 10 μm ≦ H ₃ ≦ 0.2 × H ₄
The resistance value when a voltage of 1 [kV] is applied between the first electrode and the second electrode is R ₁₂ , and the resistance value between the second electrode and the resistance value measuring electrode is (H ₂ / (H ₁ + H ₂ )) When a resistance value when a voltage of 1 [kV] is applied is R ₂₃ , 0.95 × (H ₂ / (H ₁ + H ₂ )) ≦ R ₂₃ / R ₁₂ ≦ 1.05 × ( A spacer that satisfies H ₂ / (H ₁ + H ₂ )) is judged as a good product.

In the spacer constituting the flat display device of the present invention or the spacer of the present invention, the voltage is divided while maintaining the required uniformity by satisfying the above-mentioned conditions. Accordingly, the non-uniformity of the electric field in the vicinity of the spacer does not become excessive, and the relative luminance change of the pixels along the spacer is also reduced to the extent that there is no practical problem. In the spacer, the portion where the resistance measuring electrode is present has the same potential. Therefore, from the viewpoint of uniformity of the partial pressure by the spacer, the distance H ₃ corresponding to the width in the height direction of the electrode for measuring the resistance value is sufficiently larger than the distance H ₄ corresponding to the width in the height direction of the spacer base material. It is necessary to be short, and it is desirable that 10 μm ≦ H ₃ ≦ 0.2 × H ₄ , more preferably 10 μm ≦ H ₃ ≦ 0.05 × H ₄ .

  In the spacer inspection method of the present invention, a spacer that satisfies the above-described conditions is determined as a good product. As a result, it is possible to select a spacer in which the non-uniformity of the electric field near the spacer does not become excessive. For example, a flat display device in which the relative luminance change of pixels along the spacer is reduced is manufactured by inspecting and sorting the spacers in advance and manufacturing the flat display device using only the selected spacers. be able to.

  Hereinafter, the flat display device of the present invention, the spacer of the present invention, or the spacer inspection method of the present invention may be simply referred to as the present invention. Moreover, the spacer which comprises the flat type display apparatus of this invention, the spacer of this invention, or the spacer test | inspected by the inspection method of the spacer of this invention may be only called the spacer of this invention. Furthermore, the flat display device of the present invention may be simply referred to as the display device of the present invention.

  Here, in the spacer of this invention, the spacer base material which comprises a spacer can be set as the structure which consists of high resistance rigid materials, such as a ceramic and glass. Ceramic materials include aluminum silicate compounds such as mullite, aluminum oxide such as alumina, barium titanate, lead zirconate titanate, zirconia (zirconium oxide), cordiolite, barium borosilicate, iron silicate, glass ceramic materials, etc. Examples thereof include those added with titanium oxide, chromium oxide, magnesium oxide, iron oxide, vanadium oxide, nickel oxide, and the like. For example, materials described in JP-T-2003-524280 are used. You can also. Moreover, soda-lime glass can be mentioned as glass which comprises a spacer.

In the spacer of the present invention, aluminum (Al), tungsten (W), niobium (Nb), tantalum (Ta), molybdenum as constituent materials of the first electrode, the second electrode, and the resistance measurement electrode (Mo), chromium (Cr), copper (Cu), gold (Au), silver (Ag), titanium (Ti), nickel (Ni), cobalt (Co), zirconium (Zr), iron (Fe), platinum Metals such as (Pt) and zinc (Zn); alloys (such as MoW and NiV) or compounds containing these metal elements (such as nitrides such as TiN and silicides such as WSi ₂ , MoSi ₂ , TiSi ₂ and TaSi ₂₎ ); Semiconductors such as silicon (Si); carbon thin films such as diamond; and conductive metal oxides such as ITO (indium oxide-tin), 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 chemical vapor deposition (CVD) method, a combination of an ion plating method and an etching method; Printing method; plating method (electroplating method or electroless plating method); lift-off method; laser ablation method; sol-gel method and the like. According to the screen printing method or the plating method, it is possible to directly form a strip-like electrode.

In the spacer of the present invention, an antistatic film may be provided on the surface of the spacer base material. 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, compounds containing a metalloid element such as a semi-metal and MoSe _x such as _{graphite, CrO x, NdO x, La} x Ba 2-x CuO 4, La x Ba 2-x CuO 4, La x Y 1-x CrO Oxides such as ₃ ; borides such as AlB _x and TiB _x ; carbides such as SiC; sulfides such as MoS _x and WS _x ; and nitrides such as BN, TiN and AlN; Furthermore, for example, materials described in JP-T-2004-500688 and the like 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.

In the present invention, when the spacer base material is made of a ceramic material, the ceramic base material constituting the spacer base material is, for example,
(A) Using ceramic powder as dispersoid, adding a binder to prepare a slurry for green sheet,
(B) A green sheet is obtained from the slurry for the green sheet, and then
(C) firing the green sheet;
Can be obtained. The ceramic material constituting the spacer substrate is formed by sintering the ceramic powder in the green sheet slurry. Examples of the material constituting the ceramic powder serving as the dispersoid of the green sheet slurry include the same materials as exemplified in the description of the spacer base material. If necessary, a conductivity-imparting material may be added to the slurry as a dispersoid. The conductivity-imparting material does not necessarily need to exhibit conductivity in the slurry. The conductivity-imparting material may have a chemical composition that changes when the green sheet is fired, or may have a chemical composition that does not change by firing. Specifically, by firing the green sheet, the conductivity-imparting material in the green sheet is also fired, but any material may be used as long as the fired conductivity-imparting material exhibits conductivity. Examples of the conductivity imparting material used as the dispersoid of the slurry for the green sheet include noble metals such as gold and platinum; metal oxides such as molybdenum oxide, niobium oxide, tungsten oxide, and nickel oxide; titanium carbide, tungsten carbide Metal carbides such as nickel carbide; metal salts such as ammonium molybdate. Furthermore, a mixture thereof may be used. Examples of the material constituting the binder added to the green sheet slurry include organic binder materials (for example, acrylic emulsion, polyvinyl alcohol (PVA), polyethylene glycol) or inorganic binder materials (for example, water glass). be able to.

When the flat display device is a cold cathode field electron emission display device, a cold cathode field electron emission device (hereinafter abbreviated as a field emission device) constituting an electron emission source is provided on a cathode panel,
(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 region where the cathode electrode and the gate electrode overlap, and an exposed portion of the cathode electrode at the bottom; and
(E) an electron emission portion provided on the cathode electrode exposed at the bottom of the opening,
Consists of.

  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 positioned at the bottom of the opening) or a flat type field emission device An element (a field emission element in which a substantially planar electron emission portion is provided on a cathode electrode positioned at the bottom of an opening) can be given.

  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 portion where the cathode electrode and the gate electrode overlap corresponds to an electron emission region, the electron emission regions are arranged in a two-dimensional matrix, and one or a plurality of field emission elements are arranged in each electron emission region. Is provided.

  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 layer. As a result of the collision of electrons with the phosphor layer, the phosphor layer 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 output voltage V _A of the anode electrode control circuit is normally constant, and can be, for example, 5 kilovolts 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 an overlapping region between 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 portion 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, as the material constituting the electron emission portion, 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, for example, a sputtering method or a CVD method in addition to the vacuum evaporation method.

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; a screen printing method; Plating method and electroless plating method); lift-off method; laser ablation method; sol-gel method and the like. According to the screen printing method or the plating method, for example, a strip-like cathode electrode or gate electrode can be formed directly.

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; SiN-based materials; polyimide These insulating resins 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 a screen printing method 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. As a material constituting the resistor film, a carbon-based material such as silicon carbide (SiC) or SiCN, a semiconductor material such as SiN or amorphous silicon, or a refractory metal oxide such as ruthenium oxide (RuO ₂ ), tantalum oxide, or tantalum nitride. It can be illustrated. Examples of the method for forming the resistor film include a sputtering method, a CVD method, and a screen printing method. The electrical resistance value per one electron emitting portion may be approximately 1 × 10 ⁶ to 1 × 10 ¹¹ Ω, preferably several tens of 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 glass substrates, high strain point glass, low alkali glass, non-alkali glass, soda glass (Na ₂ O · CaO · SiO ₂ ), borosilicate glass (Na ₂ O · B ₂ O ₃ · SiO ₂ ), forsterite ( 2MgO · SiO ₂ ) and lead glass (Na ₂ O · PbO · SiO ₂ ) can be exemplified.

  In the flat display device, examples of the configuration of the anode electrode and the phosphor layer include (1) a configuration in which the anode electrode is formed on the substrate and the phosphor layer is formed on the anode electrode, and (2) on the substrate. The structure which forms a fluorescent substance layer and forms an anode electrode on a fluorescent substance layer can be mentioned. In the configuration (1), a so-called metal back film that is electrically connected to the anode electrode may be formed on the phosphor layer. In the configuration (2), a metal back film may be formed on the anode electrode.

The anode electrode may be composed of one anode electrode as a whole, or may be composed of a plurality of anode electrode units. In the latter case, it is preferable that the anode electrode unit and the anode electrode unit are electrically connected by a resistor layer. As the material constituting the resistor layer, carbon, carbon carbide (SiC), SiCN, and other carbon materials; SiN materials; ruthenium oxide (RuO ₂ ), tantalum oxide, tantalum nitride, chromium oxide, titanium oxide, and other high melting point metals Examples thereof include oxides; semiconductor materials such as amorphous silicon; ITO. It is also possible to realize a stable desired sheet resistance value by combining a plurality of films such as laminating a carbon thin film having a low resistance value on the SiC resistance film. Examples of the sheet resistance value of the resistor layer include 1 × 10 ⁻¹ Ω / □ to 1 × 10 ¹⁰ Ω / □, preferably 1 × 10 ³ Ω / □ to 1 × 10 ⁸ Ω / □. The number (Q) of anode electrode units may be two or more. For example, when the total number of rows of phosphor layers arranged in a straight line is q, Q = q or q = k · Q (K is an integer of 2 or more, preferably 10 ≦ k ≦ 100, more preferably 20 ≦ k ≦ 50), or a number obtained by adding 1 to the number of spacers arranged at a constant interval. It can also be a number that matches the number of pixels or sub-pixels, or an integer fraction of the number of pixels or sub-pixels. The size of each anode electrode unit may be the same regardless of the position of the anode electrode unit, or may vary depending on the position of the anode electrode unit.

The anode electrode (including the anode electrode unit) may be formed using a conductive material layer. Examples of the method of forming the conductive material layer include various physical vapor deposition methods (PVD methods) such as an evaporation method such as an electron beam evaporation method and a hot filament evaporation method, a sputtering method, an ion plating method, and a laser ablation method; Examples include CVD method; screen printing method; metal mask printing method; lift-off method; sol-gel method. That is, it is possible to form an anode electrode by forming a conductive material layer made of a conductive material and patterning the conductive material layer based on a lithography technique and an etching technique. Alternatively, the anode electrode can be obtained by forming a conductive material based on a PVD method or a screen printing method through a mask or screen having an anode electrode pattern. The resistor layer can also be formed by a similar method. That is, a resistor layer may be formed from a resistor material, and the resistor layer may be patterned based on a lithography technique and an etching technique, or the resistor material may be provided via a mask or screen having a resistor layer pattern. The resistor layer can be obtained by formation based on the PVD method or the screen printing method. 3 × 10 ⁻⁸ m (30 nm) to 5 as the average thickness of the anode electrode on the substrate (or above the substrate) (when the partition is provided as described later, the average thickness of the anode electrode on the top surface of the partition) Examples include x10 ⁻⁷ m (0.5 μm), preferably 5 × 10 ⁻⁸ m (50 nm) to 3 × 10 ⁻⁷ m (0.3 μm).

As the constituent material of the anode electrode, molybdenum (Mo), aluminum (Al), chromium (Cr), tungsten (W), niobium (Nb), tantalum (Ta), gold (Au), silver (Ag), titanium (Ti) ), Cobalt (Co), zirconium (Zr), iron (Fe), platinum (Pt), zinc (Zn), etc .; alloys or compounds containing these metal elements (for example, nitrides such as TiN, WSi ₂ Silicide such as MoSi ₂ , TiSi ₂ , TaSi ₂ ); Semiconductor such as silicon (Si); Carbon thin film such as diamond; Conductive metal oxide such as ITO (indium oxide-tin oxide), indium oxide, zinc oxide can do. When the resistor layer is formed, the anode electrode is preferably made of a conductive material that does not change the resistance value of the resistor layer. For example, when the resistor layer is made of silicon carbide (SiC), the anode electrode is It is preferable to comprise from molybdenum (Mo).

  The phosphor layer may be composed of single-color phosphor particles or may be composed of three primary color phosphor particles. The phosphor layer is arranged in a dot pattern. Specifically, when the display device performs color display, examples of the arrangement and arrangement of the phosphor layers include a delta arrangement, a stripe arrangement, a diagonal arrangement, and a rectangle arrangement. That is, one line of the phosphor layers arranged in a straight line is occupied by a line occupied by the red light emitting phosphor layer, a line occupied by the green light emitting phosphor layer, and a blue light emitting phosphor layer. It may be comprised from the row | line | column, and it may be comprised from the row | line | column in which the red light emission fluorescent substance layer, the green light emission fluorescent substance layer, and the blue light emission fluorescent substance layer were arrange | positioned in order. Here, the phosphor layer is defined as a phosphor region that generates one bright spot in the display device. Further, one pixel (one pixel) is composed of a set of one red light emitting phosphor layer, one green light emitting phosphor layer, and one blue light emitting phosphor layer, and one subpixel is one phosphor. It is composed of layers (one red-emitting phosphor layer, one green-emitting phosphor layer, or one blue-emitting phosphor layer). A gap between adjacent phosphor layers may be filled with a light absorption layer (black matrix) for the purpose of improving contrast.

  The phosphor layer uses a luminescent crystal particle composition prepared from luminescent crystal particles. For example, a red photosensitive luminescent crystal particle composition (red phosphor slurry) is applied to the entire surface, exposed, Development is performed to form a red light-emitting phosphor layer, and then a green photosensitive light-emitting crystal particle composition (green phosphor slurry) is applied to the entire surface, exposed, and developed to form a green light-emitting phosphor layer. Further, a blue light-emitting phosphor crystal particle composition (blue phosphor slurry) is coated on the entire surface, exposed and developed to form a blue light-emitting phosphor layer. . Alternatively, 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 may be sequentially exposed and developed to form each phosphor layer. Each phosphor layer may be formed by a screen printing method, an inkjet method, a float coating method, a sedimentation coating method, a phosphor film transfer method, or the like. The average thickness of the phosphor layer on the substrate is not limited, but is preferably 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.

  The light absorption layer that absorbs light from the phosphor layer is preferably formed between adjacent phosphor layers or between the partition wall and the substrate from the viewpoint of improving the contrast of the display image. Here, the light absorption layer functions as a so-called black matrix. As the material constituting the light absorption layer, it is preferable to select a material that absorbs 90% or more of light from the phosphor layer. Such materials include carbon, metal thin films (eg, chromium, nickel, aluminum, molybdenum, etc., or alloys thereof), metal oxides (eg, chromium oxide), metal nitrides (eg, chromium nitride), heat resistance Materials such as photosensitive organic resins, glass pastes, glass pastes containing conductive particles such as black pigments and silver, and specifically, photosensitive polyimide resins, chromium oxides, and chromium oxide / chromium laminated films Can be illustrated. In the chromium oxide / chromium laminated film, the chromium film is in contact with the substrate. For example, the light absorption layer is a combination of a vacuum vapor deposition method, a sputtering method and an etching method, a vacuum vapor deposition method, a sputtering method, a combination of a spin coating method and a lift-off method, a screen printing method, a lithography technique, etc. It can be formed by a method appropriately selected depending on the method.

  In order to prevent electrons rebounding from the phosphor layer or secondary electrons emitted from the phosphor layer from entering other phosphor layers, so-called optical crosstalk (color turbidity) is generated. Alternatively, when electrons recoiled from the phosphor layer or secondary electrons emitted from the phosphor layer enter the other phosphor layer through the barrier ribs, these electrons enter the other phosphor layer. In order to prevent collision, it is preferable to provide a partition wall.

  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.

  As a planar shape of the part surrounding the phosphor layer in the partition wall (corresponding to the inner contour line of the projected image of the partition wall side surface and a kind of opening region), a rectangular shape, a circular shape, an elliptical shape, an oval shape, a triangular shape, Examples include pentagonal or more polygonal shapes, rounded triangular shapes, rounded rectangular shapes, rounded polygons, 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, lead glass colored with a metal oxide such as cobalt oxide, SiO ₂ , and a 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.

  For example, the spacer can be fixed by being sandwiched between the partition walls, or can be fixed by forming a spacer holding portion on the cathode panel and / or the anode panel and fixing the spacer. Alternatively, the spacer and the cathode panel and / or the anode panel can be fixed by frit glass, a low melting point metal or the like.

The cathode panel and the anode panel are joined at the peripheral edge, but the joining may be performed using an adhesive layer, or may be performed using a frame body made of glass or ceramic and an adhesive layer 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. As a constituent material of the adhesive layer, frit glass is generally used, but a so-called low melting point metal material having a melting point of about 120 to 400 ° C. 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, exhaust can be performed through a tip tube connected in advance to the cathode panel and / or the anode panel. The tip tube is typically a glass tube, or a metal or alloy having a low thermal expansion coefficient [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 area of the cathode panel and / or the anode panel (an effective area that is a display area in the center portion that performs a practical function as a display device) Is bonded to the periphery of the through-hole provided in the frame-like area) using frit glass or the above-mentioned low-melting-point metal material, and after the space reaches a predetermined degree of vacuum, it is sealed by thermal fusion. Or alternatively sealed by crimping. Note that it is preferable that the entire display device is once heated and then cooled before being sealed because residual gas can be released into the space and the residual gas can be removed out of the space by exhaust.

  In the present invention, examples of the electron emission source include a cold cathode field emission device (hereinafter abbreviated as a field emission device), a metal / insulating film / metal type device (MIM device), and a surface conduction electron emission device. . Further, as a flat display device, a flat display device (cold cathode field electron emission display device) provided with a cold cathode field emission device, a flat display device incorporating an MIM element, and a surface conduction electron emission device are incorporated. And a flat display device.

  In the spacer constituting the flat display device of the present invention or the spacer of the present invention, the spacer divides the voltage while maintaining the required uniformity. Accordingly, the non-uniformity of the electric field in the vicinity of the spacer does not become excessive, and the relative luminance change of the pixels along the spacer is also reduced to the extent that there is no practical problem. Further, according to the spacer inspection method of the present invention, it is possible to select a spacer in which the non-uniformity of the electric field in the vicinity of the spacer does not become excessive. It is possible to manufacture a flat display device in which the relative luminance change of the pixels along the spacer is reduced by manufacturing the flat display device using only the selected spacers by inspecting and sorting the spacers in advance. it can.

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

  FIG. 1 shows a conceptual partial end view of the flat display device of the embodiment and the spacer. The flat display device in the embodiment is a cold cathode field emission display (hereinafter abbreviated as a display device), and the cathode panel CP and the anode panel AP constituting the display device are shown in FIGS. The display panel described above has the same configuration and structure as the cathode panel CP and the anode panel AP. That is, in the display device of the embodiment, the cathode panel CP in which a plurality of Spindt type field emission elements corresponding to electron emission sources that emit electrons are formed on the support 10 and the electron emission source (Spindt type electric field). The phosphor layer 22 and the anode electrode 24 on which the electrons emitted from the emission element collide are formed on the substrate 20 and are joined at their peripheral portions, and the spacer 140 is the cathode panel CP and the anode panel. A space disposed between the AP and the cathode panel CP and the anode panel AP is held in a vacuum. Since these configurations, operations, and actions are the same as those described in the background art, description thereof is omitted here.

  With reference to FIGS. 2A and 2B, the spacer of the embodiment will be described. FIG. 2A is a schematic perspective view in which a part of the spacer 140 of the embodiment is cut out, and FIG. 2B is a schematic view of the first end surface portion 140P in the spacer 140 of the embodiment. It is typical sectional drawing for demonstrating the positional relationship of 2nd end surface part 140Q and electrode 140D for resistance value measurement. The spacer 140 according to the embodiment is a spacer disposed between the cathode panel CP and the anode panel AP. The spacer 140 includes a spacer base material 140A, a first electrode 140B, a second electrode 140C, and a strip-shaped resistance value measuring electrode 140D. The spacer base material 140A includes a first end surface portion 140P facing the anode panel AP, a second end surface portion 140Q facing the cathode panel CP, and a pair of side surface portions 140R. The first electrode 140B is provided on the first end surface portion 140P of the spacer base material 140A, and the second electrode 140C is provided on the second end surface portion 140C of the spacer base material 140A. The strip-shaped resistance value measuring electrode 140D has a first edge portion on the first end face portion side extending in parallel with the first end face portion 140P and a second edge portion on the second end face portion side extending in parallel with the second end face portion 140Q. As described above, the spacer base 140A is provided on one side surface portion 140R.

In the spacer 140 of the embodiment, the distance between the first end surface portion 140P and the first edge portion of the resistance value measuring electrode 140D is H ₁ , and the distance between the second end surface portion 140Q and the resistance value measuring electrode 140D is the _first distance portion. The distance between the two edges is H ₂ , the distance between the first edge and the second edge of the resistance measurement electrode 140D is H ₃ , and the distance between the first end face 140P and the second end face 140Q is H _4. , 0.2 × H ₄ ≦ H ₁ ≦ 0.8 × H ₄ , 0.2 × H ₄ ≦ H ₂ ≦ 0.8 × H ₄ , and 10 μm ≦ H ₃ ≦ 0.2 × H ₄ is satisfied, the resistance value when a voltage of 1 [kV] is applied between the first electrode 140B and the second electrode 140C is R ₁₂ , the second electrode 140C and the resistance value measuring electrode 140D are when the _{(H 2 / (H 1 +} H 2)) × 1 the resistance value when a voltage is applied to the [kV] R ₂₃ during, 0.95 × (H ₂ / ( _{1 + H 2)) ≦ R} 23 / R 12 ≦ 1.05 × (H 2 / (H 1 + H 2)) satisfying.

  In the display device incorporating the spacer of the present invention, the deviation between the luminance centroid obtained by measuring the luminance of the pixels along the spacer 140 and the luminance centroid obtained by measuring the luminance of the pixels separated from the spacer 140 is, It was confirmed that it was within 5 μm. The luminance center of gravity of the pixel will be described later.

  Next, a method for manufacturing the spacer of the example, a method for inspecting the spacer of the example, and a method for manufacturing the display device of the example will be described.

[Step-100]
First, a green sheet slurry is prepared. Alumina powder (Alcoa Incorporated) and titania powder (Kanto Chemical Co., Ltd.), which have been pulverized and classified so that the average particle size is 1 to 2 μm, are mixed so that the volume ratio is 98: 2. -A butyral resin binder and a surfactant are added, dispersed in a mixed solvent of toluene and ethanol, and stirred by a ball mill to obtain a slurry.

[Step-110]
Next, a green sheet is obtained from the slurry for the green sheet. In the examples, the prepared slurry was formed into a sheet having a thickness of about 100 μm by a blade coating method and sufficiently dried at 100 ° C. to obtain a green sheet. However, the present invention is not limited to this.

[Step-120]
Thereafter, the green sheet is fired to obtain a ceramic material. A ceramic material was obtained by placing the above sheet on a molybdenum setter and firing it for about 1 hour in an atmosphere of 1650 ° C. and nitrogen: hydrogen = 1: 3. Absent.

[Step-130]
Next, the spacer base material 140A is obtained by cutting the ceramic material. In the embodiment, the dimension of the spacer base material 140A is 150 mm in the longitudinal direction (X direction in FIGS. 1 and 2), 100 μm in the thickness direction (Y direction in FIGS. 1 and 2), and the height direction (FIGS. 1 and 2). Although it is 2 mm in the Z direction in FIG. 2, it is not limited thereto.

[Step-140]
Next, a first electrode 140B, a second electrode 140C, and a strip-shaped resistance measurement electrode 140D are provided. In the embodiment, platinum (Pt) is used as a material constituting these electrodes, and the first electrode 140B, the second electrode 140C, and the strip-shaped resistance measurement electrode 140D are formed by using a sputtering method and a lift-off method. did. The thickness of these electrodes was about 50 μm. In the embodiment, as described above, the distance H ₄ between the first end surface portion 140P and the second end surface portion 140Q is 2 mm, and the distance between the first end surface portion 140P and the first edge portion of the resistance value measuring electrode 140D. H ₁ is 1 mm (= 0.5 × H ₄ ), and the distance H ₂ between the second end face portion 140Q and the second edge of the resistance value measuring electrode 140D is 0.8 mm (= 0.4 × H ₄ ), The distance H ₃ between the first edge and the second edge of the resistance value measurement electrode 140D was set to 0.2 mm (= 0.1 × H ₄ ).

  By the above [Step-100] to [Step-140], the spacer 140 including the spacer base 140A, the first electrode 140B, the second electrode 140C, and the strip-shaped resistance measurement electrode 140D can be obtained.

[Step-150]
Thereafter, the spacer is inspected. That is, for the obtained spacer 140, first, a voltage of 1 [kV] is applied between the first electrode 140B and the second electrode 140C, and the resistance value R ₁₂ is set based on the relationship between the magnitude of the flowing current and the voltage. taking measurement. In the example, the resistance value R ₁₂ was distributed in a range of approximately 5 gigaΩ to 10 gigaΩ. Next, a voltage of (H ₂ / (H ₁ + H ₂ )) × 1 [kV] (more specifically about 0.44 [kV]) is applied between the second electrode 140C and the resistance value measuring electrode 140D. The resistance value R ₂₃ is measured based on the relationship between the magnitude of the applied current and the voltage. In the example, the resistance value R ₂₃ was distributed in a range of approximately 2 gigaΩ to 5 gigaΩ. Based on the obtained resistance values R ₁₂ and R ₂₃ , the spacer is 0.95 × (H ₂ / (H ₁ + H ₂ )) ≦ R ₂₃ / R ₁₂ ≦ 1.05 × (H ₂ / (H ₁ + H ₂ )) was judged to satisfy or not, and the satisfied spacers were selected as non-defective products.

[Step-160]
Next, the display device shown in FIG. 1 is assembled using the spacers 140 selected as non-defective products. The anode panel AP and the cathode panel CP are arranged so that the phosphor layer 22 and the electron emission area EA are opposed to each other with the spacer 140 interposed therebetween. The anode panel AP and the cathode panel CP (more specifically, the support body 10 and the substrate 20) are joined together at the peripheral edge via, for example, the frame body 26. At the time of joining, frit glass is applied to the joining part between the frame body 26 and the anode panel AP and the joining part between the frame body 26 and the cathode panel CP, and the frit glass is dried by pre-baking, and then the anode panel AP. The cathode panel CP and the frame are bonded together, and the 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 26 and the frit glass is exhausted through a through hole (not shown) and a tip tube (not shown), and the pressure in the space is 10 ^−4. When the pressure reaches about Pa, the tip tube is sealed by heat melting or pressure welding. In this way, the space surrounded by the anode panel AP, the cathode panel CP, and the frame 26 can be evacuated. Thereafter, wiring with necessary external circuits is performed, and the display device of the embodiment can be completed.

  By using the display device of the embodiment, a pixel in the vicinity of the spacer 140 and a pixel separated from the spacer 140 (specifically, an interval of four pixels from the pixel in the vicinity of the spacer 140 in the direction orthogonal to the longitudinal direction of the spacer is set. Luminance characteristics of the pixel at the empty position were measured. Specifically, using a display device for color display, white is displayed on the entire display region, and a pixel in the vicinity of the spacer 140 (1 subpixel in the embodiment) and a pixel separated from the spacer 140 are described below. The luminance center of gravity was measured by the method described. The driving condition of the display device is such that the voltage applied to the anode panel AP (more specifically, the anode electrode 24) is about 10 kV, and the power calculated from this voltage and the effective value of the amount of current flowing through the anode panel. Was set to approximately 20 W. The display area of the display device is about 40 cm × 30 cm.

First, with reference to (A) and (B) of FIG. FIG. 3A is a diagram schematically showing an electron beam trajectory in a pixel (one subpixel in the embodiment) located in the vicinity of the spacer 140. FIG. 3B is a diagram schematically showing the luminance distribution of the phosphor layer 22 in the state shown in FIG. Usually, the brightness of the peripheral part of the phosphor layer 22 tends to be relatively lower than the brightness of the central part of the phosphor layer 22. A broken line in FIG. 3B schematically shows a luminance contour line in the phosphor layer 22. As shown in FIG. 3B, the upper right end of the phosphor layer 22 constituting the pixel to be measured is the origin (0, 0), and the point (x _i , y _j ) on the phosphor layer 22 is set. Is given by L (x _i , y _j ), the coordinates (X _C , Y _C ) of the center of gravity of the luminance can be obtained by the following equations (1) and (2).

The luminance centroid was measured for the pixels in the vicinity of the spacer 140 and the pixels separated from the spacer 140. Specifically, the luminance distribution inside the pixel to be measured by the display device was measured with a CCD camera or the like. Using the measurement result, the luminance L (x _i , y _j ) can be obtained. Next, the coordinates (X _C , Y _C ) of the luminance centroid were calculated using the calculated luminance L (x _i , y _j ).

A pixel to be measured is configured using the coordinates (X _C1 , Y _C1 ) of the luminance centroid of the pixel near the spacer 140 and the coordinates (X _C2 , Y _C2 ) of the luminance centroid of the pixel separated from the spacer 140. The deviation amount of the luminance center of gravity when the upper right end portion of the phosphor layer 22 is used as a reference is obtained. Specifically, the distance between the luminance centroids of both may be obtained by calculation. In the example, the calculated deviation amount was 4 μm or less. According to the experiment by the inventors, if the deviation amount of the luminance center of gravity is 5 μm or less, the influence cannot be visually recognized in the display image, and the image display quality is maintained. For comparison, a comparative experiment was performed using spacers that were not judged to be non-defective, and about 30 spacers with a deviation in luminance center of gravity exceeding 5 μm were observed for 100 spacers.

  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 display device, cathode panel and anode panel, cold cathode field emission display device and cold cathode field emission device described in the embodiments are examples, and can be changed as appropriate. A method for manufacturing a panel, a cold cathode field emission display or a cold cathode field emission device is also an example, and can be appropriately changed. 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.

  In the embodiment, the electrode for measuring the resistance value is provided on the side surface portion on one side of the spacer base material and the electrode is not provided on the other side surface portion. However, the electrode is provided on the other side surface portion. The aspect provided may be sufficient. For example, the second resistance measurement electrode may be provided on the other side surface portion.

  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 may be provided in the gate electrode, a second opening connected to the plurality of first openings related to the insulating layer may be provided, and one or a plurality of electron emission portions may be provided. .

An electron emission source can also be constituted by an electron emission element commonly called a surface conduction electron emission element. This surface conduction electron-emitting 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 electrodes made of a conductive material such as (PdO), having a small area and arranged with a predetermined gap (gap) are formed in a matrix. A carbon thin film is formed on each electrode. The row direction wiring is connected to one electrode of the pair of electrodes, and the column direction wiring is connected to the other electrode of the pair of electrodes. By applying a voltage to the pair of 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 layer on the anode panel, the phosphor layer 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 conceptual partial end view of a flat display device and a spacer according to an embodiment. 2A is a schematic perspective view in which a part of the spacer of the embodiment is cut away, and FIG. 2B is a first end face portion and a second end face in the spacer of the embodiment. It is typical sectional drawing for demonstrating the positional relationship of a part and the electrode for resistance value measurement. FIG. 3A is a diagram schematically showing the trajectory of the electron beam in a pixel (in the embodiment, one subpixel) located in the vicinity of the spacer, and FIG. 3B is a diagram of FIG. In the state shown to (A), it is the figure which showed typically the luminance distribution of the fluorescent substance layer. FIG. 4 is a conceptual partial end view of a conventional cold cathode field emission display having a Spindt-type field emission device. FIG. 5 is a schematic exploded perspective view of a part of the cathode panel and the anode panel when the cathode panel and the anode panel are disassembled. 6A and 6B are diagrams schematically showing the trajectory of the electron beam in the pixel located in the vicinity of the spacer.

Explanation of symbols

CP ... cathode panel, AP ... anode panel, 10 ... support, 11 ... cathode electrode, 12 ... insulating layer, 13 ... gate electrode, 14, 14A, 14B ... Opening, 15 ... Electron emission part, 16 ... Converging electrode, 17 ... Interlayer insulating layer, 20 ... Substrate, 21 ... Partition, 22, 22R, 22G, 22B ... Phosphor Layer, 23 ... light absorption layer, 24 ... anode electrode, 25 ... spacer holding part, 26 ... frame, 31 ... cathode electrode control circuit, 32 ... gate electrode control circuit, 33 ... Anode electrode control circuit, 40 ... Spacer, 40A ... Spacer base material, 40B ... First electrode, 40C ... Second electrode, 140 ... Spacer, 140A ... Spacer Base material, 140B ... first electrode, 140C ... 2 electrode, 140D · · · for resistance measurement electrodes, 140P · · · first end surface portion, 140Q · · · second end face portion, 140R · · · side portions

Claims (6)

A cathode panel in which a plurality of electron emission sources for emitting electrons are formed on a support, and an anode panel in which a phosphor layer and an anode electrode with which electrons emitted from the electron emission source collide are formed on a substrate, A flat display device in which a space sandwiched between the cathode panel and the anode panel is held in a vacuum, bonded at the peripheral edge thereof, a spacer is disposed between the cathode panel and the anode panel,
The spacer includes a spacer base material, a first electrode, a second electrode, and a strip-shaped resistance measurement electrode. The spacer base material has a first end face portion facing the anode panel and a second end face facing the cathode panel. A first electrode is provided on the first end surface portion of the spacer base material, and a second electrode is provided on the second end surface portion of the spacer base material. The value measuring electrode includes a spacer base material such that the first edge on the first end face side extends in parallel with the first end face and the second edge on the second end face side extends in parallel with the second end face. On one side of the
The distance between the first end face and the first edge of the resistance measurement electrode is H ₁ , the distance between the second end face and the second edge of the resistance measurement electrode is H ₂ , and the resistance measurement electrode When the distance between the first edge and the second edge is H ₃ and the distance between the first end face and the second end face is H ₄ , 0.2 × H ₄ ≦ H ₁ ≦ 0.8 × H ₄ , 0.2 × H ₄ ≦ H ₂ ≦ 0.8 × H ₄ and 10 μm ≦ H ₃ ≦ 0.2 × H ₄
The resistance value when a voltage of 1 [kV] is applied between the first electrode and the second electrode is R ₁₂ , and the resistance value between the second electrode and the resistance value measuring electrode is (H ₂ / (H ₁ + H ₂ )) When a resistance value when a voltage of 1 [kV] is applied is R ₂₃ , 0.95 × (H ₂ / (H ₁ + H ₂ )) ≦ R ₂₃ / R ₁₂ ≦ 1.05 × ( A flat display device satisfying H ₂ / (H ₁ + H ₂ )).   2. The flat display device according to claim 1, wherein the spacer base material is made of a ceramic material. A cathode panel in which a plurality of electron emission sources for emitting electrons are formed on a support, and an anode panel in which a phosphor layer and an anode electrode with which electrons emitted from the electron emission source collide are formed on a substrate, Spacers that are joined at their peripheral portions and used in a flat display device in which a space sandwiched between a cathode panel and an anode panel is maintained in a vacuum, and are arranged between the cathode panel and the anode panel,
The spacer includes a spacer base material, a first electrode, a second electrode, and a strip-shaped resistance measurement electrode. The spacer base material has a first end face portion facing the anode panel and a second end face facing the cathode panel. A first electrode is provided on the first end surface portion of the spacer base material, and a second electrode is provided on the second end surface portion of the spacer base material. The value measuring electrode includes a spacer base material such that the first edge on the first end face side extends in parallel with the first end face and the second edge on the second end face side extends in parallel with the second end face. On one side of the
The distance between the first end face and the first edge of the resistance measurement electrode is H ₁ , the distance between the second end face and the second edge of the resistance measurement electrode is H ₂ , and the resistance measurement electrode When the distance between the first edge and the second edge is H ₃ and the distance between the first end face and the second end face is H ₄ , 0.2 × H ₄ ≦ H ₁ ≦ 0.8 × H ₄ , 0.2 × H ₄ ≦ H ₂ ≦ 0.8 × H ₄ and 10 μm ≦ H ₃ ≦ 0.2 × H ₄
The resistance value when a voltage of 1 [kV] is applied between the first electrode and the second electrode is R ₁₂ , and the resistance value between the second electrode and the resistance value measuring electrode is (H ₂ / (H ₁ + H ₂ )) When a resistance value when a voltage of 1 [kV] is applied is R ₂₃ , 0.95 × (H ₂ / (H ₁ + H ₂ )) ≦ R ₂₃ / R ₁₂ ≦ 1.05 × ( A spacer characterized by satisfying H ₂ / (H ₁ + H ₂ )).   The spacer according to claim 3, wherein the spacer substrate is made of a ceramic material. A cathode panel in which a plurality of electron emission sources for emitting electrons are formed on a support, and an anode panel in which a phosphor layer and an anode electrode with which electrons emitted from the electron emission source collide are formed on a substrate, In a method for inspecting a spacer disposed between a cathode panel and an anode panel, which is used in a flat panel display device in which a space between the cathode panel and the anode panel is held in a vacuum, which is joined at the peripheral portion thereof. There,
The spacer includes a spacer base material, a first electrode, a second electrode, and a strip-shaped resistance measurement electrode. The spacer base material has a first end face portion facing the anode panel and a second end face facing the cathode panel. A first electrode is provided on the first end surface portion of the spacer base material, and a second electrode is provided on the second end surface portion of the spacer base material. The value measuring electrode includes a spacer base material such that the first edge on the first end face side extends in parallel with the first end face and the second edge on the second end face side extends in parallel with the second end face. On one side of the
The distance between the first end face and the first edge of the resistance measurement electrode is H ₁ , the distance between the second end face and the second edge of the resistance measurement electrode is H ₂ , and the resistance measurement electrode When the distance between the first edge and the second edge is H ₃ and the distance between the first end face and the second end face is H ₄ , 0.2 × H ₄ ≦ H ₁ ≦ 0.8 × H ₄ , 0.2 × H ₄ ≦ H ₂ ≦ 0.8 × H ₄ and 10 μm ≦ H ₃ ≦ 0.2 × H ₄
The resistance value when a voltage of 1 [kV] is applied between the first electrode and the second electrode is R ₁₂ , and the resistance value between the second electrode and the resistance value measuring electrode is (H ₂ / (H ₁ + H ₂ )) When a resistance value when a voltage of 1 [kV] is applied is R ₂₃ , 0.95 × (H ₂ / (H ₁ + H ₂ )) ≦ R ₂₃ / R ₁₂ ≦ 1.05 × ( A spacer inspection method characterized in that a spacer satisfying H ₂ / (H ₁ + H ₂ )) is judged as a non-defective product.   6. The spacer inspection method according to claim 5, wherein the spacer substrate is made of a ceramic material.

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