JP3639732B2 - Spacer manufacturing method and image display device manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present inventionBACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a spacer disposed between a rear plate and a face plate of an image display device, and a method for manufacturing an image display device having the spacer..
[0002]
[Prior art]
Conventionally, two types of electron-emitting devices, a hot cathode device and a cold cathode device, are known. Among these, as the cold cathode device, for example, a surface conduction type emission device, a field emission type device (hereinafter referred to as FE type), a metal / insulating layer / metal type emission device (hereinafter referred to as MIM type) and the like are known. Yes.
[0003]
As surface conduction electron-emitting devices, for example, M.I.Elinson, Radio Eng. Electron Phys., 10, 1290, (1965) and other examples described later are known.
[0004]
The surface conduction electron-emitting device utilizes a phenomenon in which electron emission occurs when a current flows in parallel to a film surface in a small-area thin film formed on a substrate. As this surface conduction electron-emitting device, SnO by Erinson et al.₂In addition to those using thin films, those using Au thin films [G. Dittmer: “Thin Solid Films”, 9,317 (1972)], In₂O_Three/ SnO₂Thin film [M. Hartwell and CGFonstad: “IEEE Trans.ED Conf.”, 519 (1975)], carbon thin film [Hisa Araki et al .: Vacuum, Vol. 26, No. 1, 22 (1983) ] Have been reported.
[0005]
As a typical example of the device configuration of these surface conduction electron-emitting devices, the above-described M.P. FIG. 3 shows a plan view of a device by Hartwell et al. In the figure, reference numeral 3001 denotes a substrate, and 3004 denotes a conductive thin film made of a metal oxide formed by sputtering. The conductive thin film 3004 is formed in an H-shaped planar shape as shown. By applying an energization process called energization forming to be described later to the conductive thin film 3004, an electron emission portion 3005 is formed. The interval L in the drawing is set to 0.5 to 1 [mm], and W is set to 0.1 [mm]. For convenience of illustration, the electron emission portion 3005 is shown as a rectangular shape in the center of the conductive thin film 3004. However, this is a schematic shape and faithfully represents the actual position and shape of the electron emission portion. I don't mean.
[0006]
M.M. In the above-described surface conduction electron-emitting devices such as the device by Hartwell et al., It is common to form the electron-emitting portion 3005 by performing an energization process called energization forming on the conductive thin film 3004 before electron emission. there were. That is, the energization forming means that the conductive thin film 3004 is energized by applying a constant DC voltage or a DC voltage boosted at a very slow rate of, for example, about 1 V / min to both ends of the conductive thin film 3004. Is locally destroyed, deformed, or altered to form an electron emitting portion 3005 in an electrically high resistance state. Note that a crack occurs in a part of the conductive thin film 3004 that is locally broken, deformed, or altered. When an appropriate voltage is applied to the conductive thin film 3004 after the energization forming, electrons are emitted in the vicinity of the crack.
[0007]
Examples of the FE type include, for example, WPDyke & W.W.Dolan, “Field Emission”, Advance in Electron Physics, 8, 89 (1956), or CASpindt, “Physical Properties of Thin-Film Field Emission Cathodes. with Molybdenium Cones ”, J. Appl. Phys., 47, 5248 (1976).
[0008]
As a typical example of the element configuration of the FE type, the above-described C.I. A. A cross-sectional view of the element according to Spindt et al. Is shown. In this figure, 3010 is a substrate, 3011 is an emitter wiring made of a conductive material, 3012 is an emitter cone, 3013 is an insulating layer, and 3014 is a gate electrode. This element causes field emission from the tip of the emitter cone 3012 by applying an appropriate voltage between the emitter cone 3012 and the gate electrode 3014.
[0009]
Further, as another element configuration of the FE type, there is an example in which an emitter and a gate electrode are arranged on the substrate substantially parallel to the substrate plane, instead of the laminated structure as shown in FIG.
[0010]
Further, as an example of the MIM type, for example, C.A. Mead, “Operation of tunnel-emission Devices”, J. Appl. Phys., 32, 646 (1961) and the like are known. A typical example of the MIM type element configuration is shown in FIG. This figure is a sectional view, in which 3020 is a substrate, 3021 is a lower electrode made of metal, 3022 is a thin insulating layer having a thickness of about 100 mm, and 3023 is an upper electrode made of a metal having a thickness of about 80 to 300 mm. is there.
[0011]
In the MIM type, an appropriate voltage is applied between the upper electrode 3023 and the lower electrode 3021 to cause electron emission from the surface of the upper electrode 3023.
[0012]
Since the above-described cold cathode device can obtain electron emission at a lower temperature than a hot cathode device, a heater for heating is not required. Therefore, the structure is simpler than that of the hot cathode device, and a fine device can be produced. Further, even if a large number of elements are arranged on the substrate at a high density, problems such as thermal melting of the substrate hardly occur. Further, unlike the case where the hot cathode element operates by heating of the heater, the response speed is slow. In the case of the cold cathode element, there is also an advantage that the response speed is fast.
[0013]
For this reason, research for applying cold cathode devices has been actively conducted.
[0014]
For example, the surface conduction electron-emitting device has an advantage that a large number of devices can be formed over a large area because the structure is particularly simple and easy to manufacture among the cold cathode devices. Therefore, for example, as disclosed in Japanese Patent Application Laid-Open No. 64-31332 by the present applicant, a method for arranging and driving a large number of elements has been studied.
[0015]
As for the application of surface conduction electron-emitting devices, for example, image forming apparatuses such as image display apparatuses and image recording apparatuses, charged beam sources, and the like have been studied.
[0016]
In particular, as an application to an image display device, for example, as disclosed in US Pat. No. 5,066,883, JP-A-2-257551 and JP-A-4-28137 by the present applicant, An image display device using a combination of a conductive emission element and a phosphor that emits light when irradiated with an electron beam has been studied. An image display device using a combination of a surface conduction electron-emitting device and a phosphor is expected to have characteristics superior to those of other conventional image display devices. For example, it can be said that it is superior in that it does not require a backlight and has a wide viewing angle as compared with a liquid crystal display device that has been widespread in recent years.
[0017]
A method for driving a plurality of FE types in a row is disclosed, for example, in US Pat. No. 4,904,895 by the present applicant. As an example of applying the FE type to an image display device, for example, R.I. A flat panel display device reported by Meyer et al. Is known [R. Meyer: “Recent Development on Microtips Display at LETI”, Tech. Digest of 4th Int. Vacuum Microele-ctronics Conf., Nagahama, pp. 6- 9 (1991)].
[0018]
An example in which a large number of MIM types are arranged and applied to an image display device is disclosed in, for example, Japanese Patent Application Laid-Open No. 3-55738 by the present applicant.
[0019]
Among the image forming apparatuses using the electron-emitting devices as described above, a flat-type display device with a small depth is attracting attention as a replacement for a CRT type display device because it is space-saving and lightweight.
[0020]
FIG. 28 is a perspective view showing an example of a display panel unit constituting a flat type image display device, and a part of the panel is cut away to show the internal structure.
[0021]
In the figure, 3115 is a rear plate, 3116 is a side wall, and 3117 is a face plate. The rear plate 3115, the side wall 3116 and the face plate 3117 provide an envelope (airtight container) for maintaining the inside of the display panel in a vacuum. Forming.
[0022]
A substrate 3111 is fixed to the rear plate 3115, and N × M cold cathode elements 3112 are formed on the substrate 3111. N and M are positive integers of 2 or more, and are appropriately set according to the target number of display pixels. Further, the N × M cold cathode elements 3112 are wired by M row-directional wirings 3113 and N column-directional wirings 3114 as shown in FIG. A portion constituted by the substrate 3111, the cold cathode element 3112, the row direction wiring 3113, and the column direction wiring 3114 is referred to as a multi-electron beam source. In addition, an insulating layer (not shown) is formed between both the wirings in the row direction wiring 3113 and the column direction wiring 3114 so that electrical insulation is maintained.
[0023]
A phosphor film 3118 made of phosphor is formed on the lower surface of the face plate 3117, and phosphors (not shown) of three primary colors of red (R), green (G), and blue (B) are separately applied. Yes. Further, a black body (not shown) is provided between the color phosphors forming the fluorescent film 3118, and a metal back 3119 made of Al or the like is formed on the surface of the fluorescent film 3118 on the rear plate 3115 side. ing.
[0024]
Dx1 to Dxm and Dy1 to Dyn and Hv are electrical connection terminals having an airtight structure provided to electrically connect the display panel and an electric circuit (not shown). Dx1 to Dxm are electrically connected to the row direction wiring 3113 of the multi electron beam source, Dy1 to Dyn are electrically connected to the column direction wiring 3114 of the multi electron beam source, and Hv is electrically connected to the metal back 3119.
[0025]
The inside of the above airtight container is 10^-6As the display area of the image display device is increased because the vacuum is maintained at about [Torr], a means for preventing the deformation or destruction of the rear plate 3115 and the face plate 3117 due to the pressure difference between the inside and the outside of the hermetic container is necessary. It becomes. The method of increasing the thickness of the rear plate 3115 and the face plate 3116 not only increases the weight of the image display device, but also causes image distortion and parallax when viewed from an oblique direction. On the other hand, in FIG. 28, a structural support (called a spacer or a rib) 3120 made of a relatively thin glass plate and supporting atmospheric pressure is provided. In this way, the space between the substrate 3111 on which the multi-beam electron source is formed and the face plate 3116 on which the fluorescent film 3118 is formed is normally maintained at sub millimeters to several millimeters, and the inside of the hermetic container is maintained at a high vacuum as described above. ing.
[0026]
The image display apparatus using the display panel described above emits electrons from each cold cathode element 3112 when a voltage is applied to each cold cathode element 3112 through the external terminals Dx1 to Dxm and Dy1 to Dyn. At the same time, a high voltage of several hundred [V] to several [kV] is applied to the metal back 3119 through the container outer terminal Hv to accelerate the emitted electrons and collide with the inner surface of the face plate 3117. As a result, the phosphors of the respective colors forming the fluorescent film 3118 are excited to emit light, and an image is displayed.
[0027]
[Problems to be solved by the invention]
  As described above, an electron beam apparatus such as an image forming apparatus includes an envelope for maintaining a vacuum atmosphere inside the apparatus, an electron source disposed in the envelope, and an electron beam emitted from the electron source. It has a target to be irradiated, an acceleration electrode for accelerating the electron beam toward the target, etc., and further supports the atmospheric pressure applied to the envelope from the inside of the envelope.SpacerMay be placed inside the envelope.
[0028]
The display panel of such an image display device has the following problems.
[0029]
First, there is a possibility that spacer charging is caused when a part of electrons emitted from the vicinity of the spacer hits the spacer or ions ionized by the action of the emitted electrons adhere to the spacer. Furthermore, there is a possibility that the electrons reaching the face plate are partly reflected and scattered, and a part of the electrons hits the spacer, thereby causing spacer charging. The electrons emitted from the cold cathode device due to the charging of the spacer are bent in their orbits and reach when they are different from the normal positions on the phosphor, and the image near the spacer is distorted and displayed.
[0030]
In order to solve this problem, proposals have been made to remove the charge (hereinafter referred to as charge removal) so that a minute current flows through the spacer. There, a high resistance film is formed on the surface of the insulating spacer so that a minute current flows on the surface of the spacer.
[0031]
However, when the amount of electrons emitted from the cold cathode device is increased, the charge removal capability cannot be said to be sufficient, and the charge amount changes depending on the intensity of the electron beam. Accordingly, the deviation of the electron beam emitted from the element in the vicinity of the spacer from the normal position on the target differs depending on the intensity (luminance). For this reason, when displaying a moving image, there existed a fault of an image appearing swaying.
[0032]
Japanese Laid-Open Patent Publication No. 8-508846 has already proposed a method of reducing spacer charging and image distortion by forming a second layer having a small secondary electron emission coefficient on a part of the spacer surface. Yes.
[0033]
In view of the above problems, an object of the present invention is to reduce the influence of a member, such as a spacer, that affects the electrons emitted from the electron source.
[0034]
[Means for Solving the Problems]
The spacer manufacturing method according to the present invention includes a rear plate on which an electron source is disposed, an accelerating electrode that is disposed opposite to the rear plate, accelerates electrons emitted from the electron source, and a phosphor irradiated with the electrons. An image display apparatus comprising: a disposed face plate; and a spacer disposed between the rear plate and the face plate, the spacer having a region located within the image display region and a region located outside the image display region. In the method for manufacturing the spacer, a step of covering the substrate with a conductive first layer, and a first region located outside the image display region of the substrate covered with the first layer as a jig The second region having a secondary electron emission coefficient smaller than that of the first layer is a second region located in the image display region of the substrate held by the first layer and covered with the first layer. Cover Characterized by a step.
[0035]
  The second layer is part of the spacer surfaceTerritoryBy forming the area excluding the area, it is not a small area surface that is a joint surface with the face plate or the rear plate in the state in which the spacer is incorporated in the envelope at the time of forming the second layer, It is possible to hold on the maximum area surface, and various holding methods are possible. As a holding method, do not form the second layer on both sides of the spacer with a holding jig.TerritoryThose who hold across the areaLegalAnd so on.
[0036]
At this time, when the second layer is made of an insulating material or a material close thereto, a change in the spacer resistance defined by the first layer of the spacer due to the second layer can be suppressed. The value of the sheet resistance of the second layer varies depending on the acceleration voltage, driving conditions, element size, etc. of the image display device, but is generally more than one digit greater than the value of the sheet resistance of the high resistance film of the first layer. It is desirable that it is two or more digits larger. At this time, the sheet resistance value is 10¹²Ω / □ or more is preferable.
[0037]
  Here, the phenomenon that sufficient neutralization characteristics can be obtained even if the second layer found by the present inventors as a result of intensive studies is not formed on the entire surface of the spacer will be described. At this time, although the effect of suppressing charging depends on the driving conditions and the formation position of the second layer, the area of the spacer surface area on which the second layer is formed is approximately 1/3 or more of the area of the spacer surface. The effect of suppression is recognized, and it is possible to obtain an effect substantially equivalent to the case where it is formed on the entire surface, preferably at a half or more, and more than two-thirds. It has been found that by providing the region where the second layer is formed in a direction substantially parallel to the acceleration voltage and the electron source, the uniformity of the static elimination characteristics can be obtained. This is because the second forming region is formed at the same height in the direction in which the acceleration voltage is applied, so that the spacers can exhibit the same charge removal characteristics for each element. As described above, the second layer of the present invention is part of the spacer surface.TerritoryBy adopting a form excluding the region, the selectivity of the spacer holding method at the time of production has been dramatically increased, and it has become possible to provide a spacer having excellent mass productivity. The present invention improves the above-mentioned disadvantages of conventional spacers, and provides a spacer exhibiting high static elimination characteristics excellent in mass productivity.
[0038]
The electron beam apparatus of the present invention may have the following form.
[0039]
  (1)In the electron beam apparatus, the electrode is an accelerating electrode that accelerates electrons emitted from the electron source, and forms an image by irradiating the target with electrons emitted from the cold cathode device according to an input signal. An image forming apparatus is formed. In particular, an image display device in which the target is a phosphor is made.
[0040]
  (2)The cold cathode device is a cold cathode device having a conductive film including an electron emitting portion between a pair of electrodes, and is particularly preferably a surface conduction electron-emitting device.
[0041]
  (3)The electron source is an electron source arranged in a simple matrix having a plurality of cold cathode elements that are matrix-wired by a plurality of row-direction wirings and a plurality of column-direction wirings.
[0042]
  (4)The electron source has a plurality of cold cathode element rows each having a plurality of cold cathode elements arranged in parallel and connected at both ends (referred to as a row direction), and in a direction perpendicular to the wiring (referred to as a column direction). Accordingly, a control electrode (also referred to as a grid) disposed above the cold cathode element forms a ladder-shaped electron source that controls electrons from the cold cathode element.
[0043]
  (5)In addition, according to the idea of the present invention, the image forming apparatus is not limited to an image forming apparatus suitable for display, and the above-described light source can be used as an alternative light source such as a light emitting diode of an optical printer composed of a photosensitive drum and a light emitting diode. An image forming apparatus can also be used. At this time, by appropriately selecting the above-mentioned m row-directional wirings and n column-directional wirings, the present invention can be applied not only to a linear light-emitting source but also to a two-dimensional light-emitting source. In this case, as the image forming member,Reference form andThe material is not limited to a directly emitting substance such as a phosphor used in the embodiment, and a member that forms a latent image by charging with electrons can also be used.
[0044]
Further, according to the idea of the present invention, the present invention can be applied to a case where a member to be irradiated with electrons emitted from an electron source is other than an image forming member such as a phosphor as in an electron microscope. . Therefore, the present invention can take the form of a general electron beam apparatus that does not specify the irradiated member.
[0045]
That is, the present application includes the following inventions as inventions related to a configuration that can reduce the influence on electrons emitted from an electron source. An electron beam apparatus having an electron beam source and a first member, wherein the first member partially covers a region easily charged on a base with a low secondary electron emission coefficient material. A featured electron beam apparatus. Here, the base may be a conductive material. The conductive base may be a conductive layer provided on the base of the first member. In this case, the substrate may be insulating. The low secondary electron emission coefficient material may be provided in a layered form as a second layer on the first layer. The present invention is particularly effective when the first member is provided at a position that substantially affects the trajectory of electrons emitted from the electron source by the potential of the first member due to charging. is there. More specifically, the low secondary electron emission coefficient material is 2 smaller than the secondary electron emission coefficient of the base (the base, the conductive base layer, or both the base and the conductive layer). It is a material having a secondary electron emission coefficient. More specifically, the conductivity of the base having conductivity is higher than the conductivity of the low secondary electron emission coefficient material (the portion having the conductivity higher than that of the low secondary electron emission coefficient material). Is more likely to move the charge). In the case where a large current does not need to flow through the base, or when it is desired to suppress the current flowing through the base, the conductivity of the base may be made semiconductive. In particular, when this member is electrically connected to electrodes having different potentials (for example, the wiring electrode and the acceleration electrode of the electron-emitting device) and current flows between the electrodes, the current flows when the conductivity is high. Current will increase. Therefore, it is desirable to suppress power consumption by making the base conductivity semi-conductive. In this case, in particular, by using an insulating material as a substrate and providing a layer (first layer) having conductivity (semi-conductivity) on the layer, the conductivity of the entire first member is suitably controlled. it can. In order to suppress the conductivity of the first layer, the resistance of the first layer may be increased, that is, the first layer may be a high resistance film. Moreover, this application includes the following invention as a manufacturing method of the member in which charging is suppressed. A method of manufacturing a member in which charging is suppressed, the method including a step of holding a part of a substrate and providing a material for suppressing charging on the substrate, the held portion being a member of the member A method for producing a member, wherein the member is a portion where charging is difficult to occur. Here, the material for suppressing the charging is preferably a material that imparts conductivity, or a material that has a lower secondary electron emission coefficient than that of the substrate. In addition, the present invention is particularly effective in a configuration in which the material for suppressing charging is applied on a substrate in a liquid state.
[0046]
DETAILED DESCRIPTION OF THE INVENTION
Next, the configuration and manufacturing method of the display panel of the image display device to which the present invention is applied will be described with reference to specific examples.
[0047]
  FIG.referenceIt is a perspective view of the display panel used for form, and in order to show an internal structure, a part of panel is notched and shown.
[0048]
In the figure, 1015 is a rear plate, 1016 is a side wall, 1017 is a face plate, and 1015 to 1017 form an airtight container for maintaining the inside of the display panel in a vacuum. When assembling an airtight container, it is necessary to seal the joints of each member in order to maintain sufficient strength and airtightness. For example, frit glass is applied to the joints, and in the air or in a nitrogen atmosphere, Celsius. Sealing was achieved by baking at 400 to 500 degrees for 10 minutes or more. A method for evacuating the inside of the hermetic container will be described later. The inside of the above airtight container is 10^-6Since a vacuum of about [Torr] is maintained, a spacer 1020 is provided as an atmospheric pressure resistant structure for the purpose of preventing the destruction of the airtight container due to atmospheric pressure or unexpected impact. Reference numeral 1021 denotes a formation region of the second layer.
[0049]
A substrate 1011 is fixed to the rear plate 1015, and N × M cold cathode elements 1012 are formed on the substrate. N and M are positive integers of 2 or more, and are appropriately set according to the target number of display pixels. For example, in a display device for the purpose of displaying high-definition television, it is desirable to set the numbers N = 3000 and M = 1000 or more. The N × M cold cathode elements are simply matrix-wired by M row-directional wirings 1013 and N column-directional wirings 1014. The part constituted by 1011 to 1014 is called a multi-electron beam source.
[0050]
The multi-electron beam source used in the image display apparatus of the present invention is not limited in the material, shape or manufacturing method of the cold cathode element as long as it is an electron source in which cold cathode elements are wired in a simple matrix. Therefore, for example, a cold cathode device such as a surface conduction electron-emitting device, FE type, or MIM type can be used.
[0051]
Next, the structure of a multi-electron beam source in which surface conduction electron-emitting devices (described later) are arranged as a cold cathode device on a substrate and wired in a simple matrix will be described.
[0052]
FIG. 12 is a plan view of the multi-electron beam source used in the display panel of FIG. On the substrate 1011, surface conduction electron-emitting devices similar to those shown in FIG. 10 to be described later are arranged, and these devices are wired in a simple matrix by row direction wiring electrodes 1003 and column direction wiring electrodes 1004. An insulating layer (not shown) is formed between the electrodes at the intersecting portions of the row direction wiring electrodes 1013 and the column direction wiring electrodes 1014 so that electrical insulation is maintained.
[0053]
FIG. 11 shows a cross section taken along the line BB ′ of FIG.
[0054]
The multi-electron source having such a structure includes a row-direction wiring electrode 1013, a column-direction wiring electrode 1014, an inter-electrode insulating layer (not shown), and element electrodes 1102 and 1103 of surface conduction electron-emitting devices on a substrate in advance. After the conductive thin film 1104 was formed, each element was supplied through the row direction wiring electrode 1013 and the column direction wiring electrode 1014 to perform energization forming processing (described later) and energization activation processing (described later).
[0055]
  Reference formThe multi-electron beam source substrate 1011 is fixed to the rear plate 1015 of the hermetic container. However, when the multi-electron beam source substrate 1011 has sufficient strength, the rear plate of the hermetic container is used. Alternatively, the multi-electron beam source substrate 1011 itself may be used.
[0056]
  A fluorescent film 1018 is formed on the lower surface of the face plate 1017.Reference formIs a color display device, the phosphor film 1018 is coated with phosphors of three primary colors red, green and blue used in the field of CRT. For example, as shown in FIG. 22A, the phosphors of the respective colors are separately applied in stripes, and a black conductor 1010 is provided between the stripes of the phosphors. The purpose of providing the black conductor 1010 is to prevent the display color from being shifted even if there is a slight shift in the irradiation position of the electron beam, or to prevent the reflection of external light and lower the display cost last. For example, preventing the phosphor film from being charged up by an electron beam. For the black conductor 1010, graphite is used as a main component, but other materials may be used as long as they are suitable for the above purpose.
[0057]
Further, the method of separately applying phosphors of the three primary colors is not limited to the stripe arrangement shown in FIG. 22 (a). For example, a delta arrangement as shown in FIG. It may be an array.
[0058]
Note that when a monochrome display panel is formed, a monochromatic phosphor material may be used for the phosphor film 1018, and a black conductive material is not necessarily used.
[0059]
Further, a metal back 1019 known in the field of CRT is provided on the surface of the fluorescent film 1018 on the rear plate side. The purpose of providing the metal back 1019 is to improve the light utilization rate by specularly reflecting a part of the light emitted from the fluorescent film 1018, to protect the fluorescent film 1018 from the collision of negative ions, and the electron beam acceleration voltage. For example, to act as an electrode for applying a voltage, or to act as a conductive path for excited electrons in the fluorescent film 1018. The metal back 1019 was formed by forming a fluorescent film 1018 on the face plate substrate 1017, smoothing the surface of the fluorescent film, and then vacuum-depositing Al thereon. Note that when a low-voltage phosphor material is used for the phosphor film 1018, the metal back 1019 may not be used.
[0060]
  Also,Reference formAlthough not used, a transparent electrode made of, for example, ITO may be provided between the face plate substrate 1017 and the fluorescent film 1018 for the purpose of applying an acceleration voltage or improving the conductivity of the fluorescent film.
  FIG. 2 is a schematic cross-sectional view taken along the line AA ′ of FIG. 1, and the numbers of the respective parts correspond to those of FIG. The spacer 1020 has a high resistance film 11 as a first layer for the purpose of preventing charging on the surface of the insulating member 1. Reference numeral 1021 denotes a second layer formed of a member having a low secondary electron emission coefficient that is partially formed on the first layer 11. Further, the low resistance films 3a and 3b are formed on the contact surfaces and part of the side surfaces of the spacer facing the inside of the face plate 1017 (metal back 1019 and the like) and the surface of the substrate 1011 (row direction wiring 1013 or column direction wiring 1014). Have.
[0061]
The spacers 1020 are arranged in the necessary number and at the necessary intervals to achieve the above-described purpose, and are fixed to the inside of the face plate and the surface of the substrate 1011 by the bonding material 1041.
[0062]
The high resistance film 11 is formed on at least the surface of the insulating member 1 exposed in the vacuum in the airtight container, and the low resistance films 3a and 3b on the spacer 1020 and the bonding material are formed. Via the gate 1041, it is electrically connected to the inside of the face plate 1017 (metal back 1019 and the like) and the surface of the substrate 1011 (row direction wiring 1013 or column direction wiring 1014). In the embodiment described here, the spacer 1020 has a thin plate shape, and the spacer 1020 is arranged in parallel to the row direction wiring 1013 and is electrically connected to the row direction wiring 1013.
[0063]
The spacer 1020 has an electrical resistance sufficient to withstand a high voltage applied between the row direction wiring 1013 and the column direction wiring 1014 on the substrate 1011 and the metal back 1019 on the inner surface of the face plate 1017. It is necessary to have conductivity sufficient to prevent the surface from being charged.
Examples of the insulating member of the spacer substrate 1 include quartz glass, glass having a reduced impurity content such as Na, ceramic member such as soda lime glass, and alumina. The insulating member 1 preferably has a thermal expansion coefficient close to that of the member forming the hermetic container and the substrate 1011.
[0064]
The high resistance film 11 constituting the spacer 1020 has a current obtained by dividing the acceleration voltage Va applied to the high potential side face plate 1017 (metal back 1019 and the like) by the resistance value Rs of the high resistance film 11 as an antistatic film. Will be washed away. Therefore, the resistance value Rs of the spacer is set in a desirable range from antistatic and power consumption. The sheet resistance R / □ is 10 from the viewpoint of antistatic.¹²It is preferable that it is below Ω / □. 10 to obtain sufficient antistatic effect¹¹More preferably less than Ω / □. The lower limit of the sheet resistance depends on the spacer shape and the voltage applied between the spacers.^FiveIt is preferable that it is Ω / □ or more.
[0065]
The thickness t of the antistatic film formed on the insulating material is preferably in the range of 10 nm to 1 μm. Although it varies depending on the surface energy of the material, adhesion to the substrate, and substrate temperature, a thin film of 10 nm or less is generally formed in an island shape, and its resistance is unstable and reproducibility is poor. On the other hand, when the film thickness t is 1 μm or more, the film stress increases, the risk of film peeling increases, and the film formation time increases, resulting in poor productivity. Therefore, the film thickness is desirably 50 to 500 nm.
[0066]
The sheet resistance R / □ is ρ / t, and the specific resistance ρ of the antistatic film is 0.1 [Ωcm] to 10 to 10 from the preferred range of the sheet resistance R / □ and the film thickness t described above.⁸[Ωcm] is preferred. Furthermore, in order to realize a more preferable range of sheet resistance and film thickness, ρ is 10²Thru 10⁶It is good to use Ωcm. As described above, the temperature of the spacer rises when a current flows through the antistatic film formed thereon or when the entire display generates heat during operation. When the resistance temperature coefficient of the antistatic film is a large negative value, the resistance value decreases when the temperature rises, the current flowing through the spacer increases, and the temperature rises further. The current continues to increase until it exceeds the power supply limit. The value of the resistance temperature coefficient at which such a current runaway occurs is empirically a negative value and the absolute value is 1% or more. That is, the resistance temperature coefficient of the antistatic film is desirably less than −1%.
[0067]
As a material of the high resistance film 11 having antistatic properties, for example, a metal oxide such as tin oxide or nickel oxide can be used.
[0068]
As another material of the high resistance film 11 having antistatic properties, the nitride of aluminum and transition metal alloy can control the resistance value in a wide range from a good conductor to an insulator by adjusting the composition of the transition metal. It is a suitable material. Furthermore, it is a stable material with little change in resistance value in the manufacturing process of the display device described later. In addition, the temperature coefficient of resistance is less than -1%, and it is a material that is practically easy to use. Examples of the transition metal element include Ti, Cr, Ta and the like.
[0069]
The alloy nitride film is formed on the insulating member by thin film forming means such as sputtering, reactive sputtering in a nitrogen gas atmosphere, electron beam vapor deposition, ion plating, or ion assist vapor deposition. The metal oxide film can also be produced by a similar thin film formation method, but in this case, oxygen gas is used instead of nitrogen gas. In addition, a metal oxide film can be formed by a CVD method or an alkoxide coating method. The carbon film is produced by vapor deposition, sputtering, CVD, or plasma CVD. In particular, when producing amorphous carbon, the atmosphere during film formation should contain hydrogen or be used as a film formation gas. Use hydrocarbon gas.
[0070]
Here, the second layer having a low secondary electron emission coefficient formed in a certain region on the above-described high resistance layer as the first layer will be described.
[0071]
As the second layer, Cr₂O_Three, Nb₂O_Five, Y₂O_ThreeAn oxide layer with low secondary electron emission efficiency such as can be used. In addition, other materials such as an oxide having low secondary electron emission efficiency such as carbon nitride can be used. At this time, by using an insulating material, the spacer resistance defined by the first high resistance layer is not disturbed, and the resistance of the spacer can be prevented from being lowered. In addition, when an oxide is used, there is an effect that a condition change at the time of assembling the panel can be selected from a wide range because a characteristic change that hardly causes a state change such as surface oxidation due to heat treatment is small.
[0072]
The first layer neutralizes and removes the electric charge charged on the surface of the spacer with a current, so that the spacer is not largely charged, whereas the second layer is made of a material with low secondary electron emission efficiency, It functions to suppress positive charging of the spacer surface due to electron incidence on the spacer surface such as directly incident electrons, reflected electrons from the face plate, or secondary electron re-incidence.
[0073]
According to the present invention, it has been found that the second layer 1021 can sufficiently suppress the charge even if the formation region is a part of the spacer. Therefore, the second layer 1021 can be formed by a sputtering method, a vacuum evaporation method, a CVD method. Various film forming methods such as a method, screen printing, spraying, and dipping can be applied. In particular, the present invention can be applied to various methods excellent in mass productivity because of its extremely high selectivity with respect to a spacer substrate holding method which is problematic when the second layer 1021 is formed on the entire surface.
[0074]
The low resistance film 21 constituting the spacer 1020 electrically connects the high resistance film 11 to the high potential side face plate 1017 (metal back 1019, etc.) and the low potential side substrate 1011 (wirings 1013, 1014, etc.). In the following, the name of an intermediate electrode layer (intermediate layer) is also used. The intermediate electrode layer (intermediate layer) can have a plurality of functions listed below.
[0075]
(1) The high resistance film 11 is electrically connected to the face plate 1017 and the substrate 1011.
[0076]
As already described, the high-resistance film 11 is provided for the purpose of preventing charging on the surface of the spacer 1020. However, the high-resistance film 11 is applied to the face plate 1017 (metal back 1019 or the like) and the substrate 1011 (wiring 1013). 1014) directly or via the bonding material 1041, a large contact resistance is generated at the interface of the connection portion, and there is a possibility that charges generated on the spacer surface cannot be removed quickly. In order to avoid this, a low-resistance intermediate layer is provided on the contact surface or side surface of the spacer 1020 that contacts the face plate 1017, the substrate 1011, and the bonding material 1041.
[0077]
(2) The potential distribution of the high resistance film 11 is made uniform.
[0078]
Electrons emitted from the cold cathode element 1012 form an electron trajectory according to a potential distribution formed between the face plate 1017 and the substrate 1011. In order to prevent disturbance of the electron trajectory in the vicinity of the spacer 1020, it is necessary to control the potential distribution of the high resistance film 11 over the entire region. When the high-resistance film 11 is connected to the face plate 1017 (metal back 1019, etc.) and the substrate 1011 (wirings 1013, 1014, etc.) directly or via the bonding material 1041, the connection state is uneven due to the contact resistance at the interface of the connection portion. May occur, and the potential distribution of the high resistance film 11 may deviate from a desired value. In order to avoid this, a low resistance intermediate layer is provided in the entire length region of the spacer end portion (contact surface 3 or side surface portion 5) where the spacer 1020 contacts the face plate 1017 and the substrate 1011. By applying a potential, the potential of the entire high resistance film 11 can be controlled.
[0079]
(3) Control the orbit of emitted electrons.
[0080]
Electrons emitted from the cold cathode element 1012 form an electron trajectory according to a potential distribution formed between the face plate 1017 and the substrate 1011. With respect to electrons emitted from the cold cathode device in the vicinity of the spacer, restrictions (wiring, change of device position, etc.) associated with the installation of the spacer may occur. In such a case, in order to form an image without distortion or unevenness, it is necessary to control the trajectory of the emitted electrons to irradiate the desired position on the face plate 1017 with electrons. By providing a low resistance intermediate layer on the side surface portion 5 of the face plate 1017 and the substrate 1011 in contact with the surface plate 1017, the potential distribution in the vicinity of the spacer 1020 can have desired characteristics and the trajectory of emitted electrons can be controlled. I can do it.
[0081]
The low resistance film 21 may be selected from a material having a sufficiently low resistance value as compared with the high resistance film 11, and may be a metal such as Ni, Cr, Au, Mo, W, Pt, Ti, Al, Cu, Pd, or the like. Alloys and Pd, Ag, Au, RuO₂, Pd-Ag and other printed conductors composed of metal or metal oxide and glass, or In₂O_Three-SnO₂The material is appropriately selected from a transparent conductor such as polysilicon and a semiconductor material such as polysilicon.
[0082]
The bonding material 1041 having conductivity needs to have conductivity so that the spacer 1020 is electrically connected to the row direction wiring 1013 and the metal back 1019. That is, a frit glass to which a conductive adhesive, metal particles, or a conductive filler is added is suitable.
[0083]
In FIG. 1, Dx1 to Dxm, Dy1 to Dyn, and Hv are electrical connection terminals having an airtight structure provided to electrically connect the display panel and an electric circuit (not shown). Dx1 to Dxm are electrically connected to the row-direction wiring 1013 of the multi-electron beam source, Dy1 to Dyn are electrically connected to the column-direction wiring 1014 of the multi-electron beam source, and Hv is electrically connected to the metal back 1019 of the face plate.
[0084]
Further, in order to evacuate the inside of the hermetic container, after assembling the hermetic container, an exhaust pipe (not shown) and a vacuum pump are connected, and the inside of the hermetic container is^-7Evacuate to a vacuum level of [Torr]. Thereafter, the exhaust pipe is sealed. In order to maintain the degree of vacuum in the hermetic container, a getter film (not shown) is formed at a predetermined position in the hermetic container immediately before or after sealing. A getter film is a film formed by, for example, heating and vapor-depositing a getter material mainly composed of Ba by a heater or high-frequency heating, and the inside of an airtight container is 1 × 10 6 by the adsorption action of the getter film.^-FiveTo 1 × 10^-7The degree of vacuum is maintained at [Torr].
[0085]
The image display apparatus using the display panel described above emits electrons from each cold cathode element 1012 when a voltage is applied to each cold cathode element 1012 through the container external terminals Dx1 to Dxm and Dy1 to Dyn. At the same time, a high voltage of several hundred [V] to several [kV] is applied to the metal back 1019 through the container outer terminal Hv to accelerate the emitted electrons and collide with the inner surface of the face plate 1017. Thereby, the phosphors of the respective colors forming the fluorescent film 1018 are excited to emit light, and an image is displayed.
[0086]
Usually, the applied voltage to the surface conduction electron-emitting device 1012 of the present invention, which is a cold cathode device, is about 12 to 16 [V], and the distance d between the metal back 1019 and the cold cathode device 1012 is 8 from 0.1 [mm]. The voltage between the metal back 1019 and the cold cathode element 1012 is about 0.1 [kV] to about 10 [kV].
[0087]
  that's all,Reference formThe basic configuration and manufacturing method of the state display panel and the outline of the image display device have been described.
[0088]
  next,Reference formA method for manufacturing a multi-electron beam source used in the display panel will be described. The multi-electron beam source used in the image display apparatus of the present invention is not limited in the material, shape or manufacturing method of the cold cathode element as long as it is an electron source in which cold cathode elements are wired in a simple matrix. Therefore, for example, a cold cathode device such as a surface conduction electron-emitting device, FE type, or MIM type can be used.
[0089]
  However, a display conduction type emitting element is particularly preferable among these cold cathode elements under a situation where a display device having a large display screen and a low price is required. That is, in the FE type, the relative position and shape of the emitter cone and the gate electrode greatly affect the electron emission characteristics, and thus an extremely accurate manufacturing technique is required. This achieves a large area and a reduction in manufacturing cost. This is a disadvantageous factor. Further, in the MIM type, it is necessary to make the insulating layer and the upper electrode thin and uniform, but this is also a disadvantageous factor in achieving a large area and a reduction in manufacturing cost. In that respect, since the surface conduction electron-emitting device is relatively simple to manufacture, it is easy to increase the area and reduce the manufacturing cost. Further, the inventors have found that among the surface conduction electron-emitting devices, those in which the electron emission portion or its peripheral portion is formed of a fine particle film are particularly excellent in electron emission characteristics and can be easily manufactured. Therefore, it can be said that it is most suitable for use in a multi-electron beam source of a high-luminance and large-screen image display device. there,Reference formIn the display panel, a surface conduction electron-emitting device in which an electron emitting portion or a peripheral portion thereof is formed from a fine particle film is used. First, the basic configuration, manufacturing method and characteristics of a suitable surface conduction electron-emitting device will be described, and then the structure of a multi-electron beam source in which a number of devices are wired in a simple matrix will be described.
[0090]
[Suitable Device Configuration and Manufacturing Method for Surface Conduction Emitting Device]
There are two types of typical structures of the surface conduction electron-emitting device in which the electron emission portion or the peripheral portion thereof is formed of a fine particle film, a planar type and a vertical type.
[0091]
[Plane type surface conduction electron-emitting devices]
First, the device configuration and manufacturing method of a planar surface conduction electron-emitting device will be described.
[0092]
FIG. 10 shows a plan view (a) and a cross-sectional view (b) for explaining the configuration of a planar surface conduction electron-emitting device. In the figure, 1011 is a substrate, 1102 and 1103 are element electrodes, 1104 is a conductive thin film, 1105 is an electron emission portion formed by energization forming treatment, and 1113 is a thin film formed by energization activation treatment.
[0093]
As the substrate 1011, for example, various glass substrates including quartz glass and blue plate glass, various ceramic substrates including alumina, or the above-mentioned various substrates such as SiO 2₂A substrate in which an insulating layer made of a material is stacked can be used.
[0094]
The device electrodes 1102 and 1103 provided on the substrate 1011 so as to face the substrate surface in parallel are formed of a conductive material. For example, metals such as Ni, Cr, Au, Mo, W, Pt, Ti, Cu, Pd, Ag, etc., or alloys of these metals, or In₂O_Three-SnO₂A material may be appropriately selected from metal oxides such as silicon, semiconductors such as polysilicon, and the like. In order to form the electrode, it can be easily formed by using a combination of a film forming technique such as vacuum deposition and a patterning technique such as photolithography and etching, but it can be formed by using other methods (for example, a printing technique). No problem.
[0095]
The shapes of the device electrodes 1102 and 1103 are appropriately designed according to the application purpose of the electron-emitting device. In general, the electrode interval L is usually designed by selecting an appropriate numerical value from a range of several hundreds to several hundreds of μm, and among them, it is preferably several μm to several tens of μm for application to a display device. Range. For the thickness d of the device electrode, an appropriate value is usually selected from the range of several hundred to several μm.
[0096]
A fine particle film is used for the conductive thin film 1104. The fine particle film described here refers to a film (including an island-like aggregate) containing a large number of fine particles as a constituent element. If the fine particle film is examined microscopically, usually, a structure in which individual fine particles are arranged apart from each other, a structure in which the fine particles are adjacent to each other, or a structure in which the fine particles overlap each other is observed.
[0097]
The particle diameter of the fine particles used in the fine particle film is in the range of several to several thousand, and the preferable one is in the range of 10 to 200. The film thickness of the fine particle film is appropriately set in consideration of various conditions as described below. That is, the condition necessary for electrically connecting to the element electrode 1102 or 1103, the condition necessary for satisfactorily performing energization forming described later, and the electric resistance of the particulate film itself to an appropriate value described later. The conditions necessary for Specifically, it is set within the range of several to thousands of tons, but is preferably between 10 to 500 tons.
[0098]
Examples of materials that can be used to form the fine particle film include Pd, Pt, Ru, Ag, Au, Ti, In, Cu, Cr, Fe, Zn, Sn, Ta, W, and Pb. Metals such as PdO, SnO₂, In₂O_Three, PbO, Sb₂O_Three, And other oxides, and HfB₂, ZrB₂, LaB₆, CeB₆, YB_Four, GdB_Four, Borides such as TiC, ZrC, HfC, TaC, SiC, WC, etc., nitrides such as TiN, ZrN, HfN, etc., Si, Ge, etc. And the like, carbon, and the like, which are appropriately selected from these.
[0099]
As described above, the conductive thin film 1104 is formed of a fine particle film.^ThreeTo 10⁷It was set to be included in the range of [Ω / □].
[0100]
Note that it is desirable that the conductive thin film 1104 and the element electrodes 1102 and 1103 be electrically connected to each other, and thus a structure in which a part of the conductive thin film 1104 and the element electrodes 1102 and 1103 overlap each other is employed. In the example of FIG. 10, the overlapping is performed in the order of the substrate, the device electrode, and the conductive thin film from the bottom. However, in some cases, the substrate, the conductive thin film, and the device electrode are stacked in this order. No problem.
[0101]
In addition, the electron emission portion 1105 is a crack-like portion formed in a part of the conductive thin film 1104, and has an electrical property higher than that of the surrounding conductive thin film. The crack is formed by performing an energization forming process to be described later on the conductive thin film 1104. There are cases where fine particles having a particle diameter of several to several hundreds are arranged in the crack. In addition, since it is difficult to accurately and accurately illustrate the actual position and shape of the electron emission portion, it is schematically shown in FIG.
[0102]
The thin film 1113 is a thin film made of carbon or a carbon compound, and covers the electron emission portion 1105 and the vicinity thereof. The thin film 1113 is formed by performing an energization activation process described later after the energization forming process.
[0103]
The thin film 1113 is one of single crystal graphite, polycrystalline graphite, amorphous carbon, or a mixture thereof, and the film thickness is 500 [Å] or less, but is preferably 300 [Å] or less. preferable. In addition, since it is difficult to accurately illustrate the position and shape of the actual thin film 1113, it is schematically illustrated in FIG. In addition, in the plan view (a), an element from which a part of the thin film 1113 (a part on 1105) is removed is shown.
[0104]
  The basic configuration of the preferable element has been described above.Reference formThe following elements were used.
[0105]
That is, blue plate glass was used for the substrate 1011 and Ni thin films were used for the device electrodes 1102 and 1103. The thickness d of the device electrode was 1000 [Å], and the electrode interval L was 2 [μm].
[0106]
Pd or PdO was used as the main material of the fine particle film, the fine particle film had a thickness of about 100 [Å] and a width W of 100 [μm].
[0107]
Next, a preferred method for manufacturing a planar surface conduction electron-emitting device will be described.
[0108]
15A to 15E are cross-sectional views for explaining the manufacturing process of the surface conduction electron-emitting device, and the notations of the respective members are the same as those in FIG.
[0109]
1) First, device electrodes 1102 and 1103 are formed on a substrate 1011 as shown in FIG.
[0110]
  In the formation, the substrate 1011 is sufficiently washed in advance with a detergent, pure water, and an organic solvent, and then a material for the element electrode is deposited. (For example, vacuum deposition technology such as vapor deposition or sputtering is used as the deposition method.NoJust do it. Thereafter, the deposited electrode material is patterned using a photolithography / etching technique to form a pair of device electrodes (1102 and 1103) shown in FIG.
[0111]
2) Next, a conductive thin film 1104 is formed as shown in FIG.
[0112]
  In forming the film, first, an organic metal solution is applied to the substrate (a), dried, heated and fired to form a fine particle film, and then patterned into a predetermined shape by photolithography and etching. Here, the organometallic solution is a solution of an organometallic compound whose main element is a fine particle material used for the conductive thin film. (In particular,Reference formThen, Pd was used as a main element. Also,Reference formIn this case, the dipping method is used as the coating method, but other methods such as a spinner method and a spray method may be used. )
  In addition, as a method for forming a conductive thin film made of a fine particle film,Reference formThere are also cases where, for example, a vacuum vapor deposition method, a sputtering method, a chemical vapor deposition method, or the like is used other than the method using the organic metal solution used in the above.
[0113]
3) Next, as shown in FIG. 5C, an appropriate voltage is applied between the forming power supply 1110 between the device electrodes 1102 and 1103, and energization forming processing is performed to form the electron emission portion 1105.
[0114]
The energization forming process is a process in which a conductive thin film 1104 made of a fine particle film is energized, and a part thereof is appropriately destroyed, deformed, or altered, and changed into a structure suitable for electron emission. That is. In a portion of the conductive thin film made of the fine particle film that has been changed to a structure suitable for electron emission (that is, the electron emission portion 1105), an appropriate crack is formed in the thin film. Note that the electrical resistance measured between the device electrodes 1102 and 1103 significantly increases after the formation, compared to before the electron emission portion 1105 is formed.
[0115]
  In order to describe the energization method in more detail, FIG. 16 shows an example of an appropriate voltage waveform applied from the forming power supply 1110. When forming a conductive thin film made of a fine particle film, a pulsed voltage is preferable,Reference formIn this case, a triangular wave pulse having a pulse width T1 was continuously applied at a pulse interval T2 as shown in FIG. At that time, the peak value Vpf of the triangular wave pulse was boosted sequentially. Further, a monitor pulse Pm for monitoring the formation state of the electron emission portion 1105 was inserted between the triangular wave pulses at an appropriate interval, and the current flowing at that time was measured by an ammeter 1111.
[0116]
  Reference formIn, for example, 10^-FiveIn a vacuum atmosphere of about [torr], for example, the pulse width T1 was set to 1 [msec], the pulse interval T2 was set to 10 [msec], and the peak value Vpf was increased by 0.1 [V] for each pulse. Then, every time 5 pulses of the triangular wave were applied, the monitor pulse Pm was inserted at a rate of once. The monitor pulse voltage Vpm was set to 0.1 [V] so as not to adversely affect the forming process. The electric resistance between the device electrodes 1102 and 1103 is 1 × 10⁶At the stage when [Ω] is reached, that is, when the monitor pulse is applied, the current measured by the ammeter 1111 is 1 × 10^-7[A] The energization for the forming process was terminated at the following stage.
[0117]
  The above method isReference formThis is a preferable method for the surface conduction electron-emitting device. For example, when the design of the surface conduction electron-emitting device such as the material and thickness of the fine particle film or the device electrode interval L is changed, the condition of energization is changed accordingly. It is desirable to do.
[0118]
4) Next, as shown in FIG. 15 (d), an appropriate voltage is applied between the activation power supply 1112 between the device electrodes 1102 and 1103, and an energization activation process is performed to improve the electron emission characteristics. Do.
[0119]
The energization activation process is a process of energizing the electron emission portion 1105 formed by the energization forming process under appropriate conditions and depositing carbon or a carbon compound in the vicinity thereof. (In the figure, a deposit made of carbon or a carbon compound is schematically shown as the member 1113.) Note that, by conducting the energization activation process, the emission current at the same applied voltage is typically compared to before the conducting. Specifically, it can be increased 100 times or more.
[0120]
Specifically, 10^-FourThru 10^-FiveBy periodically applying a voltage pulse in a vacuum atmosphere within the range of [Torr], carbon or a carbon compound originating from an organic compound present in the vacuum atmosphere is deposited. The deposit 1113 is one of single crystal graphite, polycrystalline graphite, amorphous carbon, or a mixture thereof, and the film thickness is 500 [Å] or less, more preferably 300 [３００] or less.
[0121]
  In order to describe the energization method in more detail, FIG. 17A shows an example of an appropriate voltage waveform applied from the activation power supply 1112.Reference formIn FIG. 4, the energization activation process is performed by periodically applying a rectangular wave having a constant voltage. Specifically, the rectangular wave voltage Vac is 14 [V], the pulse width T3 is 1 [msec], and the pulse is activated. The interval T4 was 10 [msec]. The above energization conditions are as follows:Reference formWhen the design of the surface conduction electron-emitting device is changed, it is desirable to appropriately change the condition accordingly.
[0122]
1114 shown in FIG. 15D is an anode electrode for capturing the emission current Ie emitted from the surface conduction electron-emitting device, to which a DC high voltage power source 1115 and an ammeter 1116 are connected. (When the activation process is performed after the substrate 1011 is incorporated in the display panel, the phosphor screen of the display panel is used as the anode electrode 1114.) While the voltage is applied from the activation power supply 1112, the current is applied. The emission current Ie is measured by the total 1116 to monitor the progress of the energization activation process, and the operation of the activation power supply 1112 is controlled. An example of the emission current Ie measured by the ammeter 1116 is shown in FIG. 17B. When a pulse voltage is started to be applied from the activation power supply 1112, the emission current Ie increases with time, but eventually becomes saturated. Almost no increase. As described above, when the emission current Ie is almost saturated, the voltage application from the activation power supply 1112 is stopped, and the energization activation process is ended.
[0123]
  The above energization conditions are as follows:Reference formWhen the design of the surface conduction electron-emitting device is changed, it is desirable to appropriately change the condition accordingly.
[0124]
As described above, the planar surface conduction electron-emitting device shown in FIG.
[0125]
[Vertical surface conduction electron-emitting devices]
Next, another typical configuration of the surface conduction electron-emitting device in which the electron emission portion or its periphery is formed of a fine particle film, that is, the configuration of a vertical surface conduction electron-emitting device will be described.
[0126]
FIG. 13 is a schematic cross-sectional view for explaining the basic structure of the vertical type, in which 1201 is a substrate, 1202 and 1203 are element electrodes, 1206 is a step forming member, and 1204 is a conductive film using a fine particle film. 1205 is an electron emission portion formed by energization forming treatment, and 1213 is a thin film formed by energization activation treatment.
[0127]
The vertical type is different from the planar type described above in that one of the element electrodes (1202) is provided on the step forming member 1206, and the conductive thin film 1204 covers the side surface of the step forming member 1206. There is in point. Therefore, the element electrode interval L in the planar type in FIG. 10 is set as the step height Ls of the step forming member 1206 in the vertical type. For the substrate 1201, the device electrodes 1202 and 1203, and the conductive thin film 1204 using a fine particle film, the materials listed in the description of the planar type can be used similarly. Further, the step forming member 1206 includes, for example, SiO.₂An electrically insulating material such as
[0128]
Next, a method for manufacturing a vertical surface conduction electron-emitting device will be described. 18A to 18F are cross-sectional views for explaining the manufacturing process, and the notations of the respective members are the same as those in FIG.
[0129]
1) First, as shown in FIG. 18A, an element electrode 1203 is formed on a substrate 1201.
[0130]
2) Next, as shown in FIG. 2B, an insulating layer for forming a step forming member is laminated. For example, the insulating layer is made of SiO.₂May be laminated by sputtering, but other film forming methods such as vacuum deposition and printing may be used.
[0131]
3) Next, as shown in FIG. 3C, the device electrode 1202 is formed on the insulating layer.
[0132]
4) Next, as shown in FIG. 4D, a part of the insulating layer is removed by using, for example, an etching method to expose the device electrode 1203.
[0133]
5) Next, as shown in FIG. 5E, a conductive thin film 1204 using a fine particle film is formed. For the formation, as in the case of the planar type, for example, a film forming technique such as a coating method may be used.
[0134]
6) Next, as in the case of the planar type, an energization forming process is performed to form an electron emission portion. (The same process as the planar energization forming process described with reference to FIG. 15C may be performed.)
7) Next, as in the case of the planar type, an energization activation process is performed to deposit carbon or a carbon compound in the vicinity of the electron emission portion. (The same process as the planar energization activation process described with reference to FIG. 15D may be performed.)
As described above, the vertical surface conduction electron-emitting device shown in FIG.
[0135]
[Characteristics of surface conduction electron-emitting devices used in display devices]
The device structure and manufacturing method of the planar and vertical surface conduction electron-emitting devices have been described above. Next, the characteristics of the devices used in the display device will be described.
[0136]
FIG. 14 shows typical examples of (emission current Ie) vs. (element applied voltage Vf) characteristics and (element current If) vs. (element applied voltage Vf) characteristics of the elements used in the display device. The emission current Ie is remarkably smaller than the device current If and is difficult to show on the same scale, and these characteristics are changed by changing design parameters such as the size and shape of the device. Therefore, the two characteristics are shown in arbitrary units.
[0137]
The element used in the display device has the following three characteristics with respect to the emission current Ie.
[0138]
First, when a voltage greater than a certain voltage (referred to as a threshold voltage Vth) is applied to the device, the emission current Ie increases rapidly. On the other hand, at a voltage lower than the threshold voltage Vth, the emission current Ie hardly Not detected.
[0139]
That is, it is a nonlinear element having a clear threshold voltage Vth with respect to the emission current Ie.
[0140]
Second, since the emission current Ie changes depending on the voltage Vf applied to the device, the magnitude of the emission current Ie can be controlled by the voltage Vf.
[0141]
Third, since the response speed of the current Ie emitted from the element is high with respect to the voltage Vf applied to the element, the amount of electrons emitted from the element can be controlled by the length of time for which the voltage Vf is applied.
[0142]
Due to the above characteristics, the surface conduction electron-emitting device can be suitably used for a display device. For example, in a display device in which a large number of elements are provided corresponding to the pixels of the display screen, display can be performed by sequentially scanning the display screen by using the first characteristic. That is, a voltage equal to or higher than the threshold voltage Vth is appropriately applied to the driven element according to the desired light emission luminance, and a voltage lower than the threshold voltage Vth is applied to the non-selected element. By sequentially switching the elements to be driven, it is possible to display by sequentially scanning the display screen.
[0143]
Further, by using the second characteristic or the third characteristic, the light emission luminance can be controlled, so that gradation display can be performed.
[0144]
[Structure of multi electron beam source with simple matrix wiring of many elements]
Next, the structure of a multi-electron beam source in which the above-described surface conduction electron-emitting devices are arranged on a substrate and simple matrix wiring is described.
[0145]
FIG. 12 is a plan view of the multi-electron beam source used in the display panel of FIG. On the substrate, surface conduction electron-emitting devices similar to those shown in FIG. 10 are arranged, and these devices are wired in a simple matrix by row-direction wiring electrodes 1003 and column-direction wiring electrodes 1004. In the portion where the row direction wiring electrode 1003 and the column direction wiring electrode 1004 intersect, an insulating layer (not shown) is formed between the electrodes, and electrical insulation is maintained.
[0146]
FIG. 11 shows a cross section taken along the line BB ′ of FIG.
[0147]
The multi-electron source having such a structure includes a row-direction wiring electrode 1013, a column-direction wiring electrode 1014, an inter-electrode insulating layer (not shown), and an element electrode and a conductive thin film of a surface conduction electron-emitting device on a substrate in advance. Then, as described above, power was supplied to each element through the row direction wiring electrode 1013 and the column direction wiring electrode 1014 to perform energization forming processing and energization activation processing.
[0148]
FIG. 19 is a block diagram showing a schematic configuration of a drive circuit for performing television display based on NTSC television signals. In the figure, a display panel 1701 corresponds to the display panel described above, and is manufactured and operated as described above. Further, the scanning circuit 1702 scans the display line, and the control circuit 1703 generates a signal and the like input to the scanning circuit. The shift register 1704 shifts the data for each line, and the line memory 1705 inputs the data for one line from the shift register 1704 to the modulation signal generator 1707. A synchronization signal separation circuit 1706 separates the synchronization signal from the NTSC signal.
[0149]
In the following, the function of each part of the apparatus in FIG. 19 will be described in detail.
[0150]
First, the display panel 1701 is connected to an external electric circuit through terminals Dx1 to Dxm, terminals Dy1 to Dyn, and a high voltage terminal Hv. Among these, the terminals Dx1 to Dxm sequentially drive a multi-electron beam source provided in the display panel 1701, that is, cold cathode elements arranged in a matrix of m rows and n columns, one row (n elements) at a time. Then, a scanning signal for applying is applied. On the other hand, modulation signals for controlling the output electron beams of n elements for one row selected by the scanning signal are applied to the terminals Dy1 to Dyn. The high voltage terminal Hv is supplied with a DC voltage of, for example, 5 [kV] from the DC voltage source Va, which is sufficient to excite the phosphor with the electron beam output from the multi-electron beam source. This is the acceleration voltage for applying energy.
[0151]
Next, the scanning circuit 1702 will be described. The circuit includes m switching elements (schematically shown by S1 to Sm in the figure), and each switching element has an output voltage of a DC voltage source Vx or 0 [V] ( Any one of (ground level) is selected and electrically connected to terminals Dx1 to Dxm of the display panel 1701. Each of the switching elements S1 to Sm operates based on the control signal Tscan output from the control circuit 1703. In practice, however, it can be easily configured by combining switching elements such as FETs. . The DC voltage source Vx outputs a constant voltage so that the drive voltage applied to the element not scanned based on the characteristics of the electron emission element illustrated in FIG. 14 is equal to or lower than the electron emission threshold voltage Vth voltage. It is set to do.
[0152]
The control circuit 1703 has a function of matching the operations of the respective units so that appropriate display is performed based on an image signal input from the outside. Based on a synchronization signal Tsync sent from a synchronization signal separation circuit 1706 described below, Tscan, Tsft, and Tmry control signals are generated for each unit. The synchronization signal separation circuit 1706 is a circuit for separating a synchronization signal component and a luminance signal component from an NTSC television signal input from the outside. The synchronization signal separated by the synchronization signal separation circuit 1706 is composed of a vertical synchronization signal and a horizontal synchronization signal as is well known, but is shown here as a Tsync signal for convenience of explanation. On the other hand, the luminance signal component of the image separated from the television signal is represented as a DATA signal for convenience, and this signal is input to the shift register 1704.
[0153]
The shift register 1704 is for serial / parallel conversion of the DATA signal serially input in time series for each line of the image, and operates based on the control signal Tsft sent from the control circuit 1703. . In other words, the control signal Tsft can be rephrased as a shift clock of the shift register 1704. Data for one line (corresponding to drive data for n electron-emitting devices) subjected to serial / parallel conversion is output from the shift register 1704 as n signals Id1 to Idn.
[0154]
The line memory 1705 is a storage device for storing data for one line of an image for a necessary time, and appropriately stores the contents of Id1 to Idn according to a control signal Tmry sent from the control circuit 1703. The stored contents are output as I ′d 1 to I′dn and input to the modulation signal generator 1707.
[0155]
The modulation signal generator 1707 is a signal source for appropriately driving and modulating each of the electron-emitting devices 1012 according to each of the image data I′d1 to I′dn, and the output signals thereof are terminals Doy1 to Doyn. And applied to the electron-emitting devices 1012 in the display panel 1701.
[0156]
As described with reference to FIG. 14, the surface conduction electron-emitting device according to the present invention has the following basic characteristics with respect to the emission current Ie. That is, there is a clear threshold voltage Vth for electron emission (8 [V] in the case of a surface conduction electron-emitting device described later), and electron emission occurs only when a voltage equal to or higher than the threshold Vth is applied. Further, for a voltage equal to or higher than the electron emission threshold, the emission current Ie also changes according to the voltage change as shown in the graph of FIG. For this reason, when a pulse voltage is applied to the element, for example, no electron emission occurs even when a voltage equal to or lower than the electron emission threshold Vth is applied, but when a voltage equal to or higher than the electron emission threshold Vth is applied, the surface An electron beam is output from the conductive emission element. At that time, the intensity of the output electron beam can be controlled by changing the pulse peak value Vm. Further, it is possible to control the total amount of charges of the output electron beam by changing the pulse width Pw.
[0157]
Therefore, a voltage modulation method, a pulse width modulation method, or the like can be adopted as a method for modulating the electron-emitting device in accordance with the input signal. When implementing the voltage modulation method, a voltage modulation method circuit is used as the modulation signal generator 1707, which generates a voltage pulse of a certain length and appropriately modulates the peak value of the pulse according to the input data. be able to. Further, when implementing the pulse width modulation method, the modulation signal generator 1707 generates a pulse pulse having a constant peak value, and appropriately modulates the width of the voltage pulse according to the input data. A circuit of the type can be used.
[0158]
The shift register 1704 and the line memory 1705 can be either a digital signal type or an analog signal type. That is, it is only necessary to perform serial / parallel conversion and storage of the image signal at a predetermined speed.
[0159]
When the digital signal system is used, it is necessary to convert the output signal DATA of the synchronization signal separation circuit 1706 into a digital signal. For this purpose, an A / D converter may be provided at the output portion of the synchronization signal separation circuit 1706. . In this connection, the circuit used in the modulation signal generator is slightly different depending on whether the output signal of the line memory 1705 is a digital signal or an analog signal. That is, in the case of a voltage modulation method using a digital signal, for example, a D / A conversion circuit is used as the modulation signal generator 1707, and an amplifier circuit or the like is added as necessary. In the case of the pulse width modulation method, a modulation signal generator 1707 includes, for example, a high-speed oscillator and a counter that counts the wave number output from the oscillator, and a comparator that compares the output value of the counter with the output value of the memory. A circuit combining (comparators) is used. If necessary, an amplifier for amplifying the pulse width-modulated modulation signal output from the comparator to the driving voltage of the electron-emitting device can be added.
[0160]
In the case of a voltage modulation method using an analog signal, for example, an amplifier circuit using an operational amplifier or the like can be adopted as the modulation signal generator 1707, and a shift level circuit or the like can be added if necessary. In the case of the pulse width modulation method, for example, a voltage controlled oscillation circuit (VOC) can be adopted, and an amplifier for amplifying the voltage up to the driving voltage of the electron-emitting device can be added as necessary.
[0161]
In the image display apparatus to which the present invention can be applied, electron emission is generated by applying a voltage to each electron-emitting device via the external terminals Dox1 to Doxm and Doy1 to Doyn. A high voltage is applied to the metal back 1019 or transparent electrode (not shown) via the high voltage terminal Hv to accelerate the electron beam. The accelerated electrons collide with the fluorescent film 1018, and light is emitted to form an image.
[0162]
Next, the ladder-type arrangement electron source substrate and the image display apparatus using the same will be described with reference to FIGS.
[0163]
In FIG. 20, 1011 is an electron source substrate, 1012 is an electron-emitting device, and Dx1 to Dx10 of 1126 are common wirings connected to the electron-emitting device. A plurality of electron-emitting devices 1012 are arranged in parallel in the X direction on the substrate 1011 (this is referred to as an element row). A plurality of these element rows are arranged on a substrate to form a ladder type electron source substrate. By appropriately applying a driving voltage between the common wirings of each element row, each element row can be driven independently. That is, an electron beam having a voltage equal to or higher than the electron emission threshold may be applied to an element row that emits an electron beam, and a voltage equal to or lower than an electron emission threshold may be applied to an element row that does not emit an electron beam. Further, the common wirings Dx2 to Dx9 between the element rows may be the same wiring, for example, Dx2 and Dx3.
[0164]
FIG. 21 is a diagram illustrating a structure of an image forming apparatus including an electron source having a ladder arrangement. 1120 is a grid electrode, 1121 is a hole for electrons to pass through, and 1122 is D_ox1, D_ox2 ... D_oxThe container outer terminal 1123 is composed of G1, G2,... Gn connected to the grid electrode 1120, and 1011 is an electron source substrate in which the common wiring between the element rows is the same wiring as described above. In addition, the same code | symbol as FIG. 20, FIG. 21 shows the same member. A difference from the image forming apparatus (FIG. 1) having the simple matrix arrangement described above is that a grid electrode 1120 is provided between the electron source substrate 1011 and the face plate 1017.
[0165]
In the above-described panel structure, a spacer 120 can be provided between the face plate 1017 and the rear plate 1015 as required in terms of the atmospheric pressure structure regardless of whether the electron source arrangement is a matrix wiring or a ladder type arrangement.
[0166]
A grid electrode 1120 is provided between the substrate 1011 and the face plate 1017. The grid electrode 1120 can modulate the electron beam emitted from the surface conduction electron-emitting device 1012, and allows the electron beam to pass through a striped electrode provided perpendicular to the ladder-type device row. Therefore, one circular opening 1121 is provided corresponding to each element. The shape and installation position of the grid do not necessarily have to be as shown in FIG. 21, and a large number of mesh openings may be provided as openings, and may be provided, for example, around or near the surface conduction electron-emitting device. Good.
[0167]
The container outer terminal 1122 and the grid container outer terminal 1123 are electrically connected to the drive circuit of FIG.
[0168]
In this image forming apparatus, each electron beam is applied by simultaneously applying a modulation signal for one image line to the grid electrode array in synchronization with the sequential driving (scanning) of each element row (one line). It is possible to control the irradiation of the phosphor and display an image line by line.
[0169]
The configurations of the two image display apparatuses described above are examples of the image forming apparatus to which the present invention can be applied, and various modifications can be made based on the idea of the present invention. Although the NTSC system is mentioned as the input signal, the input signal is not limited to this, and a TV signal (high quality TV) system including a larger number of scanning lines can be adopted besides the PAL and SECAM systems.
[0170]
Further, according to the present invention, it is possible to provide an image forming apparatus suitable not only for a television broadcast display device but also for a display device such as a video conference system or a computer. Furthermore, it can also be used as an image forming apparatus as an optical printer composed of a photosensitive drum or the like.
[0171]
【Example】
  Examples belowAnd reference examplesThe structure of the spacer, which is a feature of the present invention, will be further described.
[0172]
  Examples described belowAnd each reference example, As a multi-electron beam source, the above-described N × M (M = 3072, M = 1024) surface conduction electron-emitting devices of the type having an electron emission portion in the conductive fine particle film between the electrodes are used. A multi-electron beam source having a matrix wiring (see FIGS. 1 and 12) with a plurality of row-directional wirings and N column-directional wirings was used.
[0173]
  [Reference example 1]
  Reference example 1Then, a display panel having the spacer 1020 shown in FIG. Hereinafter, a detailed description will be given with reference to FIGS. 1 and 2. First, the substrate 1011 in which the row direction wiring electrode 1013, the column direction wiring electrode 1014, the inter-electrode insulating layer (not shown), and the element electrodes of the surface conduction type emission element 1012 and the conductive thin film are formed on the substrate in advance is mounted on the rear plate. 1015. Next, of the surface of the insulating member 1 made of soda lime glass, a high resistance film 11 described later is formed on four surfaces exposed in the airtight container, and the low resistance film 3 (3a, 3b) is formed on the contact surface. A spacer 1020 (height 4 mm, plate thickness 0.2 mm, length 1 mm) was fixed on the row direction wiring 1013 of the substrate 1011 at equal intervals in parallel with the row direction wiring 1013. Thereafter, a face plate 1017 having a fluorescent film 1018 and a metal back 1019 attached to the inner surface is disposed 10 mm above the substrate 1011 via a side wall 1016, and each junction of the rear plate 1015, the face plate 1017, the side wall 1016, and the spacer 1020. Fixed. The joint between the substrate 1011 and the rear plate 1015, the joint between the rear plate 1015 and the side wall 1016, and the joint between the face plate 1017 and the side wall 1016 are coated with frit glass (not shown), and 400 ° C. to 500 ° C. in the atmosphere. And sealed for 10 minutes or more.
[0174]
  The spacer 1020 is a paste made of a conductive paste and an insulating paste and containing PdO as a main component on the row direction wiring 1013 (line width 0.3 mm) on the substrate 1011 side and on the metal back 1019 surface on the face plate 1017 side. The material is placed through a conductive paste (not shown) formed by dispersing granular glass filler with Au plating on the surface, and at the same time as sealing the above airtight container, at 400 ° C to 500 ° C in the atmosphere. By baking for 10 minutes or more, adhesion and electrical connection were also performed. In addition,Reference example 1As shown in FIG. 23, the fluorescent film 1018 adopts a stripe shape in which each color phosphor 1301 extends in the column direction (Y direction), and the black conductor 1010 has each color phosphor (R, G, B). Fluorescent films arranged so as to separate not only between 1301 but also between pixels in the Y direction are used, and the spacer 1020 is a region (line width) parallel to the row direction (X direction) of the black conductor 1010. 300 [μm]) through a metal back 1019. Note that, when performing the above-described sealing, each color phosphor 1301 and each element disposed on the substrate 1011 must correspond to each other, so that the rear plate 1015, the face plate 1017, and the spacer 1020 are positioned sufficiently. Combined.
[0175]
The inside of the airtight container completed as described above is evacuated by a vacuum pump through an exhaust pipe (not shown), and after reaching a sufficient degree of vacuum, the row direction wiring electrode is passed through the container outer terminals Dx1 to Dxm and Dy1 to Dyn. A multi-electron beam source was manufactured by supplying power to each element through 1013 and the column direction wiring electrode 1014 and performing the above-described energization forming process and energization activation process.
[0176]
Next, 10^-6The exhaust pipe (not shown) was welded by heating with a gas burner at a degree of vacuum of about [Torr], and the envelope (airtight container) was sealed.
[0177]
Finally, a getter process was performed to maintain the degree of vacuum after sealing.
[0178]
  Reference example 1The second layer formation region 1021 was formed in the region of three-fifths of the spacer surface area on the face plate side.
[0179]
First, the 1st layer used as the base layer of a 2nd layer is demonstrated.
[0180]
  Also,Reference example 1The high resistance film 11 as the first layer was produced as follows.
[0181]
  A Ti—Al alloy nitride film was formed on the spacer 112 made of blue glass by simultaneously sputtering a Ti and Al target with a high frequency power source. The sputtering gas is a mixed gas of Ar: N2 of 1: 2, and the total pressure is 1 mTorr. At this time, it is possible to adjust the specific resistance of the alloy nitride film by adjusting the high frequency power applied to the Ti and Al targets,Reference example 1, The sheet resistance value of the high resistance film is 8 × 10⁹[Ω / □].
[0182]
  hereThe secondA method for forming the two layers will be described.Reference example 1Then, yttrium oxide was formed as the second layer by dipping. Figure 4Reference example 14 (a) and 4 (b) are diagrams showing a spacer holding method. FIG. 2B is a view showing a cross section AA ′ in FIG. In FIG. 4, reference numeral 101 denotes a spacer substrate on which a high resistance film (not shown) and a low resistance portion (not shown) of the first layer are formed, 102 denotes a second formation region in the spacer substrate 101, and 103 denotes a spacer. The holding portion, 104 is a drive transmission portion, and L is the length of the spacer substrate pressing portion.
[0183]
  Reference example 1, The drive transmission unit 104 is connected to a drive mechanism that can move in the vertical direction, and drives the spacer substrate 101 in the direction of the arrow. The length of the presser portion L was 1.2 mm.Reference example 1In this example, SYM-Y01 (manufactured by Kojundo Chemical Laboratory Co., Ltd.), which is a yttrium oxide carboxylate solution, was used as a coating solution for dipping.
[0184]
The spacer substrate 101 was connected to the driving mechanism, immersed in the coating solution up to the upper end of the second layer forming portion 102, the spacer was pulled up at a lifting speed of 10 mm / mim, and the coating solution was applied to a part of the spacer. Next, after drying at 120 ° C./10 min, the second yttrium oxide layer was formed in the region 102 while maintaining the temperature at 450 ° C./2 hr.
[0185]
In the image display apparatus using the display panel as shown in FIG. 1 and FIG. 2 completed as described above, each cold cathode element (surface conduction type emitting element) 1012 has a container external terminal Dx1 to Dxm, Dy1. Electrons are emitted by applying a scanning signal and a modulation signal through signal generation means (not shown) through ~ Dyn, and a high voltage is applied to the metal back 1019 through a high voltage terminal Hv to accelerate the emitted electron beam. Electrons collided with the fluorescent film 1018 to excite and emit the respective color phosphors 1301 (R, G, B in FIG. 23), thereby displaying an image. The applied voltage Va to the high voltage terminal Hv was 5 [kV] to 30 [kV], and the applied voltage Vf between the wirings 1013 and 1014 was 14 [V].
[0186]
At this time, two-dimensionally arranged light emitting spot arrays are formed in two dimensions including the light emitting spots due to the emitted electrons from the cold cathode element 1012 located near the spacer 1020, and a clear color image display with good color reproducibility can be achieved. Even when the spacer 1020 is provided, it is possible to obtain a high-quality image without beam deviation.
[0187]
  [Reference example 2]
  As the material of the spacer, blue plate glass was used, and as the low resistance film, Al formed by sputtering was used.
[0188]
The method of forming the low resistance film will be described. After forming Al by sputtering as a low resistance film material on both surfaces (the widest surface of the spacer), a part was removed using sand blasting, leaving both ends. .
[0189]
  Reference example 2In the first layer, the high resistance film isReference example 1Is similar toReference example 1It was formed by the same method.
[0190]
  Reference example 2In the method, the second layer was formed by sputtering while holding the spacer. This method will be described with reference to FIGS. FIG. 5 is a view for explaining the spacer holding method, and FIG. 6 is an enlarged perspective view of the spacer pressing portion in FIG. In the figure, 201 denotes a spacer, 202 denotes a second layer forming portion, 203 denotes a holding spacer member, 204 denotes a base plate, and 205 denotes a fixing holding portion.
[0191]
  Reference example 2In this case, the holding spacer member 203 and the spacer 201 are sandwiched and held on the base plate 204 by the fixing pressing portion 205, so that the second layer forming portion 202 and the non-forming portion sandwiched between the holding portions at the time of sputtering can be obtained. Are separated.Reference example 2The second layer was formed by sputtering a chromium oxide target in Ar to form a chromium oxide layer having a thickness of about 5 nm. The formation area of the second layer was about half of the face plate side.
[0192]
The spacer height was 2.5 mm, the spacer length was 60 mm, and the spacer thickness was approximately 0.2 mm.
[0193]
  Also,Reference example 1Similarly, the spacer 1020 is made of a conductive paste and an insulating paste on the row wiring 1013 (line width 0.3 mm) on the substrate 1011 side and on the metal back 1019 side on the face plate 1017 side, and is mainly composed of PdO. The paste material is disposed through a conductive paste (not shown) formed by dispersing granular glass filler with Au plating on the surface, and at the same time as sealing the airtight container, at 400 ° C. to 500 ° C. in the atmosphere. By baking at 10 ° C. for 10 minutes or more, adhesion and electrical connection were also performed.
[0194]
  PictureWhen an acceleration voltage of 6 kV was applied to the image forming apparatus, it was possible to obtain a high-quality image without beam deviation even in the vicinity of the spacer.
[0195]
  As explained above,Reference example 2However, it is possible to obtain an image forming apparatus having a spacer in which the second layer is partially formed by a method with excellent mass productivity.
[0196]
  [Reference example 3]
  Reference example 3In, the second layer is formed by sputtering using a mask, and the formation region of the second layer is the central portion of the spacer.
[0197]
  Referring to FIG. 7, reference numeral 301 denotes a spacer, 302 denotes a mask for sputtering, and 303 denotes a mask opening. In addition,Reference example 3The width L of the opening was 2 mm.
[0198]
  A second layer was formed on the surface of the spacer 301 in the mask opening 303 by using the mask 302. In addition,Reference example 3Then, niobium oxide was used as a sputtering target, and a niobium oxide layer was formed to a thickness of 5 nm by sputtering in an argon atmosphere.
[0199]
Prior to the formation of the second layer, the high resistance film of the first layer was formed to a thickness of 100 nm by sputtering in an Ar atmosphere using a nickel oxide target. Note that the first layer is entirely covered, and the mask 302 was not used when the first layer was formed.
[0200]
  Using the spacer created as described above,Reference example 1As a result, it was possible to obtain a high-quality image with no beam deviation even in the vicinity of the spacer.
[0201]
  As explained above,Reference example 3However, it is possible to obtain an image forming apparatus having a spacer in which the second layer is partially formed by a method with excellent mass productivity.
[0202]
  [Reference example 4]
  Reference example 4, Planar field emission (FE) type electron-emitting deviceThe electricThe example used as a child emission element is shown.
[0203]
FIG. 24 is a top view of a planar FE type electron emission electron source. 3101 is an electron emission portion, 3103 and 3104 are a pair of device electrodes for applying a potential to the electron emission portion 3101, and 3113 is a row direction wiring. Reference numeral 3114 denotes a column direction wiring, and 1020 denotes a spacer.
[0204]
  By applying a voltage between the device electrodes 3103 and 3104, electrons are emitted from the sharp tip in the electron emission portion 3101, and the electrons are attracted to an acceleration voltage (not shown) provided facing the electron source. And collides with a phosphor (not shown) to cause the phosphor to emit light.Reference example 4InReference example 1In the same manner as in the above, a spacer is formed and arranged to form an image display device,Reference example 1When the same spacer was used to drive the same, it was possible to obtain a high-quality image in which beam deviation was suppressed even in the vicinity of the spacer.
[0205]
  As explained above,Reference example 4However, it is possible to obtain an image forming apparatus having a spacer in which the second layer is partially formed by a method with excellent mass productivity.
[0206]
  [Reference Example 5]
  FIG.Reference Example 5It is the image display apparatus perspective view which partly cut out for demonstrating.Reference Example 5In FIG. 2, the formation region of the second layer is located on the electron source substrate side of the spacer.
[0207]
  In FIG. 3, 1501 is a second layer non-formation region, 1502 is a second layer formation region,Reference example 1Is the same.
[0208]
  Reference Example 5The second layer forming method and the image forming apparatus manufacturing method are as follows:Reference example 1Is the same. In addition,Reference example 1The difference is that the length of the spacer in the direction between the face plate and the rear plate is 3.6 mm, and the length of the presser L in FIG. 4 is 1.1 mm.
[0209]
  Reference Example 5In this image display apparatus, it is possible to obtain a high-quality image with no beam deviation even in the vicinity of the spacer.
[0210]
  As explained above,Reference Example 5However, it is possible to obtain an image forming apparatus having a spacer in which the second layer is partially formed by a method with excellent mass productivity.
[0211]
  [Example]
  ExampleThe spacer extends not only within the display area of the image display apparatus but also outside the display area, and the formation area of the second layer is disposed only within the display area of the image display apparatus. It is not placed outside the area. 8 and 9 are diagrams for explaining the present embodiment. FIG. 8 is a diagram for explaining the relationship between the image forming unit and the spacer arrangement in the image forming apparatus. FIG. 9 is a diagram illustrating the second layer on the spacer. It is explanatory drawing about the holding method of the spacer at the time of forming.
[0212]
In the figure, reference numeral 601 denotes an image forming region, 101 denotes a spacer substrate on which a high resistance film (not shown) and a low resistance portion (not shown) are formed, and 102 denotes a second layer in the spacer substrate 101. A formation region, 103 is a spacer holding portion, and 104 is a drive transmission portion.
[0213]
In this embodiment, as shown in FIG. 8, the spacer substrate 101 is arranged in the panel in order to realize the atmospheric pressure resistant structure, and in this, the second layer formation region is only the image formation region. Yes. Further, the size of one spacer is 4 mmH × 200 mmL × 0.2 mmW, and the second layer is formed in a portion having a length of 180 mmL.
[0214]
By using this method, the second layer is formed in the image forming region 601 in which a large number of electrons fly in the space, so that the disturbance of the electron trajectory in the image forming unit is suppressed, and the second layer is formed on the entire surface of the spacer substrate. As in the case of forming the image forming apparatus, a high-quality image forming apparatus can be provided.
[0215]
  The first layer and the second layer areReference example 1It was produced using the same method. At this time, as shown in FIG. 9, the substrate was formed by changing the pulling direction of the substrate only when the second layer 102 was formed. In FIG. 9, the surface on the paper surface is the surface having the maximum area of the spacer, and in this embodiment, the spacer is held using the back surface and the surface on the paper surface.
[0216]
As described above, also in this embodiment, it is possible to obtain an image forming apparatus having a spacer in which the second layer is partially formed by a method with excellent mass productivity.
[0217]
Further, as described above, by partially forming the layer, the restriction on the holding portion can be relaxed, the spacer can be prevented from falling off the holding jig, and the setting labor can be reduced. This also improves the yield. In particular, when the first layer and the second layer are formed, the number of film forming steps is increased, and therefore, the application of the present invention that can improve the yield is effective.
[0218]
Here, FIG. 29A and FIG. 29B show the configuration of the spacer holding jig in the case of forming a film by sputtering. FIG. 29A is an enlarged view of the spacer pressing portion, and FIG. 5B is an A-A ′ sectional view thereof. Reference numeral 5001 denotes a spacer, 5002 denotes a spacer holding portion, and 5003 denotes a base plate. In the invention relating to the present application, there is no need to use this holding jig.
[0219]
[Other Examples]
In addition, the present invention can be applied to any electron-emitting device among cold-cathode electron-emitting devices other than a surface conduction electron-emitting device (SCE). As a specific example, there is a field emission type electron-emitting device in which a pair of opposed electrodes as described in Japanese Patent Laid-Open No. 63-274047 by the present applicant is configured along a substrate surface forming an electron source.
[0220]
The present invention can also be applied to an image forming apparatus using an electron source other than a simple matrix type. For example, in an image forming apparatus that performs SCE selection using a control electrode as described in JP-A-2-257551 by the applicant, the spacer of the present invention is used between the electron source and the control electrode. Can do.
[0221]
Further, according to the idea of the present invention, the image forming apparatus according to the present invention is not limited to display, but as a light emitting source that replaces a light emitting diode of an optical printer composed of a photosensitive drum and a light emitting diode, etc. The image forming apparatus of the present invention can also be used. At this time, by appropriately selecting the above-mentioned m row-directional wirings and n column-directional wirings, the present invention can be applied not only to a linear light-emitting source but also to a two-dimensional light-emitting source.
[0222]
Further, according to the idea of the present invention, the present invention can also be applied to a case where a member to be irradiated with electrons emitted from an electron source is a member other than an image forming member, such as an electron microscope. Therefore, the present invention can take the form of an electron beam apparatus that does not specify the irradiated member.
[0223]
【The invention's effect】
As described above, according to the present invention, the electron beam is attracted to the spacer in the vicinity of the spacer by partially providing it on the spacer surface by using a method that is excellent in mass productivity of the second layer having a small secondary electron emission coefficient. Is mitigated, and the non-uniformity of the image near the spacer is reduced. Accordingly, it is possible to provide an image forming apparatus with reduced image non-uniformity in the vicinity of the spacer at a low cost.
[0224]
Further, when the second layer is formed, a surface having the largest area among the surfaces exposed in the space in the apparatus is used as a surface for holding the spacer substrate, and a holding jig is brought into contact therewith and held. The holding force of the spacer substrate being manufactured can be increased. For this reason, it becomes possible to suppress significantly the fall of the yield by the fall of a spacer, etc.
[0225]
In addition, the electron irradiation object is not specified, and the same effect can be exhibited in an electron generator that forms a multi-plane electron source such as an apparatus that forms a latent image or an electron microscope.
[Brief description of the drawings]
[Figure 1]Reference form and reference example 1The perspective view which notched and showed a part of display panel of the image display apparatus by FIG.
[Figure 2]Reference example 1FIG. 3 is a cross-sectional view of the display panel taken along the line AA ′.
[Fig. 3]Reference Example 5It is the figure for demonstrating this, and is the perspective view which notched and showed a part of display panel.
[Fig. 4]Reference example 1It is a figure for demonstrating this, and is explanatory drawing of the formation method of a 2nd layer.
[Figure 5]Reference example 2It is a figure for demonstrating this, and is explanatory drawing of the formation method of a 2nd layer.
[Fig. 6]Reference example 2It is a figure for demonstrating this, and is explanatory drawing of the formation method of a 2nd layer.
[Fig. 7]Reference example 3It is a figure for demonstrating this, and is explanatory drawing of the formation method of a 2nd layer.
[Fig. 8] of the present inventionExampleFIG. 4 is a diagram for explaining the relationship between the image forming unit and the spacer arrangement in the image forming apparatus.
FIG. 9 shows the present invention.ExampleIt is a figure for demonstrating this, It is explanatory drawing of the holding method of the spacer at the time of forming a 2nd layer in a spacer.
FIG. 10Reference form and2A is a plan view of a planar surface conduction electron-emitting device according to an embodiment of the present invention, and FIG.
FIG. 11Reference form and1 is a partial cross-sectional view of a substrate of a multi-electron beam source according to an embodiment of the present invention.
FIG.Reference form and1 is a plan view of a substrate of a multi-electron beam source according to an embodiment of the present invention.
FIG. 13Reference form and1 is a cross-sectional view of a vertical surface conduction electron-emitting device according to an embodiment of the present invention.
FIG. 14Reference form and3 is a graph showing typical characteristics of a surface conduction electron-emitting device according to an embodiment of the present invention.
15 is a cross-sectional view showing a manufacturing process of the planar surface conduction electron-emitting device of FIG.
FIG. 16 shows an applied voltage waveform in the energization forming process.
FIG. 17 shows an applied voltage waveform (a) and a change in emission current Ie (b) during energization activation processing.
18 is a cross-sectional view showing a manufacturing process of the vertical surface conduction electron-emitting device of FIG.
FIG. 19Reference form and1 is a block diagram showing a schematic configuration of a drive circuit of an image display device according to an embodiment of the present invention.
FIG. 20Reference form andFIG. 2 is a schematic plan view of a ladder-type array electron source according to an embodiment of the present invention.
FIG. 21Reference form and1 is a perspective view of a flat display device having a ladder-type array of electron sources according to an embodiment of the present invention.
FIG. 22 is a plan view illustrating the phosphor array of the face plate of the display panel.
FIG. 23 is a plan view illustrating a phosphor array of a face plate of a display panel.
FIG. 24Reference example 4It is a figure for demonstrating this, and is explanatory drawing of an electron source.
FIG. 25 is a surface conduction electron-emitting device according to a conventional example.
FIG. 26 shows an FE type element according to a conventional example.
FIG. 27 shows an MIM type element according to a conventional example.
FIG. 28 is a perspective view in which a part of a display panel of an image display device according to a conventional example is cut away.
FIG. 29 is an explanatory diagram of a spacer fixing method during film formation for comparison.
[Explanation of symbols]
  1 Insulating material
  2 High resistance film
  3a, 3b Low resistance part
  12,3104,3105 X direction wiring
  13, 3106, 3107 Y-direction wiring
  14 Interlayer insulation layer
  15 Electron emitter
  18 Thin film for electron emission formation (thin film including electron emission part)
  20 mask
  20a opening
  23,3101 Electron emitter
  30,32 Ammeter
  31, 33 Power supply
  34 Anode electrode
  57,151 recess
  58 Conductive connection
  101 Spacer substrate
  102 Formation region of second layer in spacer substrate
  103 Spacer holding part
  104 Drive transmission part
  140,150 Insulating substrate
  201 Spacer
  202 Second layer forming part
  203 Spacer member for holding
  204 Base plate
  205 Fixing part for fixing
  301,5001 Spacer
  302 Mask for sputtering
  303 Mask opening
  500 display panel
  501 Drive circuit
  502 Display Panel Controller
  503 Multiplexer
  504 decoder
  505 I / O interface circuit
  506 CPU
  507 Image generation circuit
  508, 509, 510 Image memory interface circuit
  511 Image input interface circuit
  512,513 TV signal receiving circuit
  514 Input section
  1020 Spacer
  1021, 1502 Second layer formation region
  1501 Second layer non-formation region
  1701 Display panel
  1702 Scanning circuit
  1703 Control circuit
  1704 Shift register
  1705 line memory
  1706 Sync signal separation circuit
  1707 Modulation signal generator
  3001 Insulating substrate
  3002 Thin film for electron emission region formation
  3003, 3101 Electron emission part
  3004 Thin film including electron emitting portion
  3102 and 3103 A pair of element electrodes for applying a potential to the electron emitting portion 3101
  3113 Row direction wiring
  3114 Column wiring
  L Length of spacer substrate holder

Claims (4)

A rear plate disposed with an electron source, a face plate disposed opposite to the rear plate and accelerating the electrons emitted from the electron source and a phosphor irradiated with the electrons; and the rear plate In the method of manufacturing the spacer of the image display device, comprising the spacer disposed between the plate and the face plate and having a spacer located in the image display region and a region located outside the image display region. a step of coating a conductive first layer, said first substrate coated with a layer, to the first held by the first realm a jig which is located outside the image display area the substrate coated with a layer, that has a step of coating with a second layer having a second secondary electron emission coefficient smaller than that of the first layer area of which is positioned in the image display area Features Method of manufacturing over service. 2. The method for manufacturing a spacer according to claim 1 , wherein the second layer is made of an insulating material. A rear plate disposed with an electron source, a face plate disposed opposite to the rear plate and accelerating the electrons emitted from the electron source, and a phosphor irradiated with the electrons; and the rear plate In the manufacturing method of an image display apparatus provided with the spacer which is arrange | positioned between a plate and the said faceplate, and has the area | region located in an image display area, and the area | region located outside an image display area, the said spacer is a claim A method for manufacturing an image display device, which is manufactured by the method according to 1 or 2. 4. The image display device manufacturing method according to claim 3 , wherein a plurality of row-direction wirings and a plurality of column-direction wirings for supplying current to the plurality of electron-emitting devices are arranged on the rear plate via an insulating layer. The plurality of electron-emitting devices are arranged in a matrix on the rear plate , and each of the plurality of electron-emitting devices is connected to each of the plurality of row-direction wirings and each of the plurality of column-direction wirings. A method for manufacturing an image display device .

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