JP2009032488A - Image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a long-life image display device high in quality and reliability by reducing line defects of an image display panel by preventing disconnection of an image signal wire extraction terminal, and by repairing and recovering the disconnection. <P>SOLUTION: The image signal wire extraction terminal 8a extracted to the outside from one end of an image signal wire 8 is formed by a two-layer film structure comprising a first image signal wire extraction terminal 811 and a second image signal wire extraction terminal 812, thereby connecting a generation part of disconnection S of the first image signal wire extraction terminal 811 by the second image signal wire extraction terminal 812 to be electrically connected. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a flat-type image display device using electron emission into a vacuum formed between a front substrate and a rear substrate, and more particularly, a video signal wiring lead terminal coupled to a tip portion of a video signal wiring. The present invention relates to a laminated film structure.

  Conventionally, a color cathode ray tube has been widely used as a display device excellent in high luminance and high definition. However, with the recent improvement in image quality of information processing devices and television broadcasting, there is an increasing demand for flat image display devices (flat panel displays: FPD) that have high brightness and high definition characteristics and are lightweight and space-saving. ing.

  As typical examples, liquid crystal display devices, plasma display devices and the like have been put into practical use. In particular, a self-luminous display device using electron emission from an electron source to a vacuum as a device capable of achieving high brightness is called an electron emission image display device or a field emission image display device. Various flat-type image display devices such as an organic EL display characterized by power consumption have been put into practical use.

  Among flat-panel image display devices, a self-luminous flat panel display is known to have a configuration in which electron sources are arranged in a matrix, and one of them is the use of a cold cathode that is minute and can be integrated. An electron emission type image display device is also known.

  In a self-luminous flat panel display, the cold cathode has a Spindt type, a surface conduction type, a carbon nanotube type, a metal-insulator-metal laminated MIM (Metal-Insulator-Metal) type, and a metal-insulation. A thin-film electron source such as a metal-insulator-semiconductor (MIS) type or a metal-insulator-semiconductor-metal type in which a body-semiconductor is laminated is used.

  The electron emission type FPD includes a rear substrate including the electron source as described above, and a phosphor layer and an anode that forms an acceleration voltage for causing electrons emitted from the electron source to collide with the phosphor layer. There is known an image display panel that includes a front substrate and a support that serves as a sealing frame that seals the internal space of both substrates facing each other in a predetermined vacuum state. An FPD is operated by combining a drive circuit with this display panel.

  In an image display device having an electron source, a plurality of video signal wirings extending in one direction and arranged in parallel in the other direction intersecting the one direction, an insulating film formed to cover the video signal wirings, The number of the scanning signal wirings that are arranged in one direction so as to extend in the other direction on the insulating film and intersect the video signal wirings and to which the scanning signals are sequentially applied, and the intersections of the video signal wirings and the scanning signal wirings A back substrate having an electron source provided in the vicinity of the unit, and the back substrate has a substrate made of an insulating material, and the wiring is formed on the substrate.

  In such a configuration, the scanning signal is sequentially applied to the scanning signal wiring in the other direction. Further, an electron source is provided at each intersection of the scanning signal wiring and the image signal wiring on the substrate, and both the wiring and the electron source are connected by a feeding electrode, and current is supplied to the electron source. A front substrate having a plurality of color phosphor layers and an anode is provided on the inner surface facing the rear substrate. The front substrate is formed of a light transmissive material suitable for glass. Then, the two substrates are bonded together, and a support body serving as a sealing frame is inserted and sealed at the inner periphery, and the interior formed by the back substrate, the front substrate and the support body is evacuated.

  The electron source is located at the intersection between the video signal wiring and the scanning signal wiring as described above, and the amount of electrons emitted from the electron source (the emission on / off state) due to the potential difference between the video signal wiring and the scanning signal wiring. Control). The emitted electrons are accelerated by a high voltage applied to the anode located on the front substrate, and are also projected into the phosphor layer on the front substrate and excited to excite the colored light according to the emission characteristics of the phosphor layer. Color develops.

  Each electron source is paired with a corresponding phosphor layer to constitute a unit pixel. Usually, one pixel (color pixel, pixel) is composed of unit pixels of three colors of red (R), green (G), and blue (B). In the case of a color pixel, the unit pixel is also called a sub-pixel (sub-pixel).

  In the flat-type image display device as described above, a plurality of spacing members (hereinafter referred to as spacers) are generally arranged and fixed in a display region surrounded by the support between the rear substrate and the front substrate. The distance between the substrates is maintained at a predetermined distance in cooperation with the support. This spacer is generally formed of a plate-like body formed of an insulating material such as glass or ceramics, and is usually installed at a position where the operation of the pixel is not hindered for each of the plurality of pixels.

Further, the support serving as a sealing frame is fixed to the inner peripheral edge of the rear substrate and the front substrate with a sealing member such as frit glass, and the fixing portion is hermetically sealed to form a sealing region. The degree of vacuum inside the display area formed by both the substrates and the support is, for example, about 10 ⁻⁵ to 10 ⁻⁷ Torr.

  In the sealing region between the support and both substrates, a video signal wiring lead terminal coupled to the video signal wiring formed on the rear substrate and a video signal wiring lead terminal coupled to the video signal wiring penetrate. Usually, the support used as the sealing frame is fixed to the rear substrate and the front substrate with a sealing member such as frit glass. The video signal wiring lead terminal and the scanning signal wiring lead terminal are led out through a sealing region which is a hermetically sealed portion between the sealing frame and the rear substrate. Patent Document 1 discloses an image forming apparatus having a structure that is bent at a lower portion of a support at a portion where a signal wiring is taken out to the outside.

  In addition, a plurality of video signal wirings and scanning signal wirings are provided on the rear substrate, and the rear substrate and the front substrate are disposed on the surface of the rear substrate having the video signal wiring and the scanning signal wiring through a frame. In a wiring board for a display panel having a container and having a phosphor layer and an anode in the hermetic container, the cross sections of the video signal wiring and the scanning signal wiring in the orthogonal projection region on the rear substrate of the phosphor layer and the anode are An image forming apparatus having a wiring structure in which an average angle formed with the back substrate is an obtuse angle, and an average angle formed with the back substrate is a cross section of the video signal wiring and the scanning signal wiring in the region where the frame is arranged is patented It is disclosed in Document 2.

JP-A-9-277586 JP 2003-151474 A

  However, as described above, a back substrate formed by connecting a plurality of electron sources in a matrix by video signal wiring and scanning signal wiring and a front substrate on which a phosphor layer is formed are bonded to face each other. When configuring an image display device as a display panel, various problems arise when the display panel is increased in area and quality.

  In particular, the video signal wiring and the scanning signal wiring use a thick glass paste made of a metal material and a glass-based material as an electrode material in order to satisfy a desired wiring resistance. However, in order to improve the quality of the image display device. When the resolution is further increased, it is necessary to sufficiently reduce the widths of the video signal lines and the scanning signal lines in the display area. Although it depends on the purpose of use of the image display device, it is indispensable for the high-definition image display device that can be sufficiently utilized for general purposes to have a wiring width of about several tens of μm or less. The wiring width problem is exactly the same for the video signal wiring lead terminal coupled to the video signal wiring and the scanning signal wiring lead terminal coupled to the scanning signal wiring.

  The video signal wiring and the scanning signal wiring are arranged on the rear substrate, and the wiring lead-out terminals are led out to the outside through a gap facing the rear substrate surface and the support end surface. In this gap, a sealing member such as frit glass is disposed and hermetically sealed to form a sealed region.

  In such a configuration, in order to obtain a display image having a desired brightness without causing image defects, a large amount of current is constantly applied from the video signal wiring lead terminal and the scanning signal wiring lead terminal to the video signal wiring and the scanning signal wiring, respectively. There is a problem that a voltage drop occurs along the video signal wiring and the scanning signal wiring.

  In order to solve this problem, it is necessary to reduce the electrical resistance of the video signal wiring and the scanning signal wiring in order to reduce the voltage drop. The video signal wiring and the scanning signal wiring are made of a thin film made of a metal material such as Al (aluminum) or Al alloy. For example, in order to reduce the electric resistance, the metal thin film constituting the video signal wiring and the scanning signal wiring is used. It is necessary to increase (thicken) the film thickness. However, when the film thickness is increased, the stress of the video signal wiring and the scanning signal wiring is increased, which causes a problem that it is easily peeled off from the rear substrate. Therefore, the video signal wiring and the scanning signal wiring must be made thin (thin). That is, it is indispensable to form each signal wiring and its wiring lead terminal with a small film thickness.

  However, when the film thickness is reduced, the video signal wiring lead terminal 8a led out from one end of the video signal wiring 8 as shown in the enlarged plan view of the main part of the video signal wiring terminal portion in FIG. During the shaping process, the disconnection S is likely to occur due to some factor, which causes a line defect in the image display panel, which impairs the quality and reliability of the image display device. In the figure, reference numeral 14 denotes an interlayer insulating film that retains insulation with a scanning signal wiring (not shown).

  Therefore, the present invention has been made to solve the above-described conventional problems, and its purpose is to reduce line defects of the image display panel by preventing disconnection of the video signal wiring lead terminal, An object of the present invention is to provide a long-life image display device with high quality and reliability.

  Another object of the present invention is to provide a long-life image display device with high quality and reliability by reducing line defects in the image display panel by repairing the disconnection of the video signal wiring lead terminal. .

  In order to achieve such an object, an image display device according to the present invention has a video signal wiring lead terminal in which at least one end of the video signal wiring is led out from the display region through a sealing region where the back substrate and the support face each other. This video signal lead-out terminal is constituted by a plurality of laminated structures, so that the disconnection occurrence portion is coupled, so that the problems of the background art can be solved.

  According to the present invention, since the disconnection of the video signal wiring lead terminal can be prevented, the line defect of the image display panel can be reduced, and a long-life image display device with high quality and reliability can be realized. An extremely excellent effect is obtained.

  In addition, according to the present invention, it is possible to repair and recover the disconnection that occurred during the processing of the video signal wiring lead terminal, thereby reducing the line defect of the image display panel, and having a long life with high quality and reliability. An extremely excellent effect that an image display apparatus can be realized is obtained.

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

  FIGS. 1 to 5 are views for explaining an embodiment of the image display device of the present invention. FIG. 1A is a plan view seen from the front substrate side, and FIG. 2) is a side view seen from the direction A, FIG. 2 is a schematic plan view of the back substrate shown by removing the front substrate of FIG. 1, and FIG. 3 is a schematic cross-sectional view of the back substrate along the line BB of FIG. 4 is a schematic cross-sectional view of the front substrate corresponding to the back substrate, FIG. 4 is a schematic cross-sectional view of the back substrate taken along the line CC in FIG. 2, and a schematic cross-sectional view of the front substrate corresponding to the back substrate. 5 is a schematic cross-sectional view of the back substrate taken along the line DD of FIG. 2 and a schematic cross-sectional view of the front substrate corresponding to the back substrate.

  1 to 5, reference numeral 1 is a back substrate, 2 is a front substrate, and both the substrates 1 and 2 are each formed of a glass plate having a thickness of several millimeters, for example, about 3 mm. Reference numeral 3 is a frame formed in a frame shape. This frame 3 is composed of a glass plate or a frit glass sintered body having a thickness of several mm, for example, about 3 mm, and is a combination of a single member or a plurality of rod members. Are formed in a substantially frame shape, and are inserted in a peripheral portion between the back substrate 1 and the front substrate 2.

  The frame body 3 is inserted around a peripheral portion between the back substrate 1 and the front substrate 2, and both end surfaces thereof are airtightly joined to the back substrate 1 and the front substrate 2. The thickness of the frame 3 is about several millimeters to several tens of millimeters, and its height is set to a dimension that is substantially equal to the distance between the back substrate 1 and the front substrate 2.

Reference numeral 4 is an exhaust pipe, and the exhaust pipe 4 is fixed to the outer surface of the back substrate 1. Reference numeral 5 denotes a sealing member. The sealing member 5 is, for example, a low melting point frit glass such as PbO: 75 wt% to 80 wt%, B ₂ O ₃ : about 10 wt%, others: 10 wt% to 15 wt%, etc. And a glass material including an amorphous type frit glass is known, and the frame 3, the back substrate 1 and the front substrate 2 are joined and hermetically sealed. Yes.

The vacuum region 6 including the display region surrounded by the frame 3, the rear substrate 1, the front substrate 2, and the sealing member 5 is exhausted through the exhaust pipe 4, for example, 10 ⁻⁵ Pa to 10 ⁻⁷ Pa. The degree of vacuum is maintained. Further, as described above, the exhaust pipe 4 is attached to the outer surface of the back substrate 1 and communicates with the through hole 7 formed through the back substrate 1 so that the exhaust pipe 4 is sealed after the exhaust is completed. Is done.

  Reference numeral 8 denotes a stripe-shaped video signal wiring. The video signal wiring 8 is made of, for example, an aluminum (Al) film or an aluminum alloy film containing aluminum as a main component. Direction) and juxtaposed in the other direction (X direction). As will be described later, the video signal wiring 8 includes a tunnel insulating layer and a field insulating layer on the upper surface. The video signal wiring 8 airtightly penetrates from the vacuum region 6 to the joining region between the frame 3 and the rear substrate 1 and extends to the end portion on the long side of the rear substrate 1. The signal wiring lead terminal 8a is used.

  As the video signal wiring lead terminal 8a, for example, an Al film is used in the first video signal wiring lead terminal 811 in the lower layer, and aluminum (Al) whose main component is Al in the second video signal wiring lead terminal 812 in the upper layer. Al—Nd alloy film of Neodymium (Nd) is used. In this case, the first video signal wiring lead terminal 811 is formed to have a larger film thickness (thickness) than the second video signal wiring lead terminal 812, and the entire electric resistance value of the video signal wiring lead terminal 8a. Is reduced.

  The video signal wiring lead terminal 8a is formed by forming the first video signal wiring lead terminal 811 with an Al film having a thickness of about 800 nm and the second video signal wiring lead terminal 812 with Al-Nd. An alloy film is formed to a thickness of about 600 nm.

  Further, the video signal wiring lead terminal 8a is formed as an upper layer film on the first video signal wiring lead terminal 811 as a lower layer film formed on the rear substrate 1 as shown in a schematic plan view of the main part in FIG. The second video signal wiring lead terminal 812 is formed to have a two-layer structure formed by overlapping. The first video signal wiring lead terminal 811 in which the disconnection S does not occur is formed by laminating the second video signal wiring lead terminal 812, and the disconnection S is partially generated in the first video signal. A second video signal wiring lead terminal 812 is formed on the wiring lead terminal 811 so as to cover the disconnection S, thereby constituting a two-layered video signal wiring lead terminal portion in which the disconnection S is conducted.

  Further, in FIG. 6, an insulating tunnel insulating film TAO for electrically connecting the terminal portion of the flexible printed wiring board to be electrically connected to the external circuit by thermocompression bonding is provided at the most distal portion of the video signal wiring lead terminal 8a. A film is formed.

  According to such a configuration, the first video signal wiring lead terminal 811 in which the disconnection S has occurred is electrically connected by the lamination of the second video signal wiring lead terminals 812. Since the disconnection S generated in the first video signal wiring lead terminal 811 of the lower layer film during processing is covered and repaired by the second video signal wiring lead terminal 812 of the upper layer film, the disconnection S can be recovered. . Further, by forming the second video signal wiring lead terminal 812 after forming the first video signal wiring lead terminal 811, the occurrence of the disconnection S can be prevented in advance.

  The video signal wiring lead terminal 8a uses an Al film for the first video signal wiring lead terminal 811 in the lower layer, and the second video signal wiring lead terminal 812 in the upper layer replaces the Al—Nd alloy film, for example. An Ir / Pt / Au film or the like may be used.

  According to this configuration, the video signal wiring lead terminal 8a has a two-layer film structure in which the second video signal wiring lead terminal 812 is formed again (as a pattern of the terminal portion) on the first video signal wiring lead terminal 811. By doing so, it is possible to electrically couple the portion where the disconnection S occurred in the first video signal wiring lead terminal 811 during the processing of the video signal wiring lead terminal 8a.

  Reference numeral 9 denotes a stripe-shaped scanning signal wiring, and the scanning signal wiring 9 extends on the video signal wiring 8 in the other direction (X direction) intersecting therewith and extends in one direction (Y direction). It is installed side by side. The scanning signal wiring 9 has a laminated film structure of an aluminum film 92 and an aluminum alloy film 94 mainly composed of aluminum or a laminated film structure of aluminum alloy films having different specific resistances. The scanning signal wiring 9 airtightly penetrates the joining region between the frame 3 and the rear substrate 1 from the vacuum region 6 and extends to the end portion on the short side of the rear substrate 1. The lead terminal 9a is used.

  Further, the scanning signal electrode 9 is replaced with, for example, an Ir / Pt / Au film instead of a laminated film structure of an aluminum film 92 and an aluminum alloy film 94 mainly composed of aluminum or an aluminum alloy film having a different specific resistance. May be used. The video signal wiring lead terminal 8a and the scanning signal wiring lead terminal 9a are provided only on one end side of each corresponding wiring, but may be provided on both end sides of the back substrate 1.

  Reference numeral 10 denotes an MIM type electron source. The electron source 10 is provided in the tunnel insulating layer of the video signal wiring 8 in the vicinity of each intersection of the scanning signal wiring 9 and the video signal wiring 8. . The electron source 10 is electrically connected to the scanning signal wiring 9 and the connection electrode 11. An interlayer insulating film 14 is disposed between the video signal wiring 8 and the scanning signal electrode 9. As the interlayer insulating film 14, for example, a silicon oxide film, a silicon nitride film, or silicon can be used.

Reference numeral 12 denotes a spacer. The spacer 12 is made of an insulating material such as a ceramic material, has an unevenly distributed resistance value, and is formed into a rectangular thin plate shape and the insulating substrate. It is composed of a coating layer 122 that covers the surface of 121 and has less uneven distribution of resistance. The spacer 12 has a resistance value of about 10 ⁸ Ω · cm to 10 ⁹ Ω · cm, and has a configuration in which the resistance value is unevenly distributed as a whole.

  The spacers 12 are substantially parallel to the frame 3 and are arranged upright every other on the scanning signal wiring 9, and are bonded and fixed to the back substrate 1 and the front substrate by an adhesive member 13. The spacer 12 may be bonded and fixed to the substrate only at one end side. Further, the spacer 12 is usually disposed at a position that does not hinder the operation of each pixel.

  The dimensions of the spacer 12 are set according to the substrate dimensions, the height of the frame 3, the substrate material, the spacer spacing, the spacer material, etc. In general, the height is substantially the same as the frame 3, The thickness can be several tens of μm to several mm or less, the length can be about 20 mm to 1000 mm, and even longer, but about 80 mm to 300 mm is a practical value.

  On the other hand, on the inner surface of the front substrate 2 to which one end side of the spacer 12 is fixed, a phosphor layer 15 for red, green, and blue is arranged in a window section partitioned by a BM (black matrix) film 16 for light shielding. A metal back (anode electrode) 17 made of a metal thin film is provided by, for example, a vapor deposition method so as to cover them to form a phosphor screen.

  The metal back 17 is a light reflecting film for reflecting the light emitted to the side opposite to the front substrate 2, that is, the back substrate 1 toward the front substrate 2 and increasing the light extraction efficiency. It also has a function to prevent the charging of the surface. In addition, although the metal back 17 is shown as a surface electrode, it may be a stripe electrode that intersects the scanning signal wiring 9 and is divided for each pixel column.

For example, Y ₂ O ₃ S: Eu (P22-R) is used for red, ZnS: Cu, Al (P22-G) is used for green, and ZnS: Ag, Cl (P22 is used for blue. -B) can be used respectively. The phosphor layer 15 has an average particle size of phosphor particles of, for example, about 4 μm to 9 μm and a film thickness of, for example, about 10 μm to 20 μm.

Due to the configuration of the phosphor screen, the electrons emitted from the electron source 10 are accelerated and projected onto the phosphor layer 15 constituting the corresponding pixel. As a result, the phosphor layer 15 emits light of a predetermined color and is mixed with the light emission colors of the phosphors of other pixels to form a color pixel of a predetermined color. Further, although the anode electrode 17 is shown as a surface electrode, it can also be a stripe electrode that intersects the scanning signal wiring 9 and is divided for each pixel column.

  According to the configuration of the first embodiment, the video signal wiring lead terminal 8a has a two-layer structure of the first video signal wiring lead terminal 811 and the second video signal wiring lead terminal 812. Since the disconnection occurrence portion of one video signal wiring lead terminal 811 can be electrically coupled, the video signal wiring lead terminal 8a can be recovered when a disconnection failure occurs in the first video signal wiring lead terminal 811. It becomes. Further, even when a disconnection occurs over a plurality of locations of the first video signal wiring lead terminal 811, the disconnection failure can be recovered and repaired. Therefore, line defects in the image display panel can be reduced.

  Next, the manufacturing process of the video signal wiring, the scanning signal wiring, the electron source and the like related to the image display device of the present invention will be described with reference to FIGS.

  7 to 18, each figure (a) is a schematic plan view, each figure (b) is a schematic sectional view taken along the line CC of each figure (a), and each figure (c) is each figure (a). FIG. 5 is a schematic cross-sectional view taken along the line D-D of FIG. This electron source is a MIM electron source.

  First, as shown in FIG. 7, for example, an aluminum film for forming the video signal wiring lead terminal 8a on a not-shown video signal wiring lead terminal forming portion on an insulating substrate such as glass constituting the back substrate 1 is sputtered. To a thickness of about 800 nm. Thereafter, first video signal wiring lead terminals 811 having a substantially striped shape as lower layers were formed at predetermined intervals by the patterning process and the etching process.

  Next, a second video signal wiring lead terminal 812 which is an upper layer film of the video signal wiring 8 and the video signal wiring lead terminal 8a is formed on substantially the entire surface of the insulating substrate on which the first video signal wiring lead terminal 811 is formed. A metal film for forming is formed. As the material of the video signal wiring 8 and the second video signal wiring lead terminal 812, an aluminum alloy mainly composed of aluminum was used. One of the reasons for using this Al is that it is possible to use the characteristic that a high-quality insulating film can be formed by anodic oxidation. Here, an Al—Nd alloy doped with 2 atomic% of neodymium (Nd) was used. For film formation, a sputtering method was used, and the film thickness was about 600 nm.

  Next, after the metal film is formed, a second video signal wiring lead terminal 812 which is an upper layer film of the stripe-shaped video signal wiring 8 and video signal wiring lead terminal 8a is formed by a patterning process and an etching process as shown in FIG. Formed. As a result, in the video signal wiring lead terminal forming portion (not shown) on the rear substrate 1, the second video signal wiring lead terminal 812 serving as the upper film is laminated on the first video signal wiring lead terminal 811 serving as the lower film. A two-layer video signal wiring lead terminal 8a is formed.

  Further, the wiring width of the video signal wiring 8 and the video signal wiring lead-out terminal 8a varies depending on the size and resolution of the image display device, but the pitch of the subpixel is about 100 μm to 200 μm. For the etching, for example, a wet etching method using a mixed aqueous solution of phosphoric acid, acetic acid, and nitric acid is used. Since this wiring has a simple and wide stripe structure, the resist can be patterned by an inexpensive proximity exposure method or a printing method.

  Next, as shown in FIG. 9, a field insulating film 81 and a tunnel insulating layer 82 are formed on the surface of the video signal wiring 8 to restrict the electron emission portion and prevent electric field concentration on the edge of the video signal wiring 8. First, a portion corresponding to a portion that will become an electron emitting portion in the future is masked with a resist film at a substantially central portion of the film width on the video signal wiring 8 shown in FIG. 9, and the other portions are selectively anodized thickly. Thus, a field insulating film 81 to be a protective insulating film is formed.

  In this operation, when the formation voltage is about 200 V, a field insulating film 81 having a thickness of about 270 nm is formed. Thereafter, the resist film is removed and the surface of the remaining video signal wiring 8 is anodized. For example, when the formation voltage is 6 V, a tunnel insulating layer 82 having a thickness of about 10 nm is formed on the video signal wiring 8.

  Next, as shown in FIG. 10, an interlayer insulating film 14 and a second insulating film 24 are formed thereon by sputtering. This film formation can also use CVD. As the interlayer insulating film 14, when Si is used for the second insulating film 24, a material having a different etching rate from the second insulating film 24, such as a silicon oxide or a silicon nitride film, is used.

As will be described later, when the second insulating film 24 is processed by dry etching to form an undercut portion, the etching selection is performed so that the etching amount of the interlayer insulating film 14 is smaller than that of the second insulating film 24. This is to make the material secureable. Here, a silicon nitride film SiN in which the interlayer insulating film 14 is formed by reactive sputtering in an atmosphere of Ar and N ₂ is used, and the film thickness is about 200 nm. When the field insulating film 81 formed by anodic oxidation has a pinhole, the interlayer insulating film 14 fills in the defect and plays a role of maintaining insulation between the video signal wiring 8 and the scanning signal wiring.

  On the other hand, Si of the second insulating film 24 was formed by sputtering in an Ar atmosphere using a Si target doped with B, P, or the like. The film thickness was about 200 nm. Doped Si formed by sputtering is not activated, and can be used as a very high resistance semi-insulating material as in the case of a substantially intrinsic semiconductor. When Si oxide or Si nitride is used for the interlayer insulating film 14, the etching rate is further reduced as compared with the coupling using SiN, so that high selectivity with the second insulating film 24 can be obtained.

  Next, as shown in FIG. 11, an aluminum film 91 for forming the scanning signal wiring 9 was formed by sputtering so as to cover the entire surface of the second insulating film 24. The film thickness was about 4.5 μm. Subsequently, as shown in FIG. 12, the aluminum film 91 is processed by a photoetching process, and a video signal is formed at a position between the adjacent tunnel insulating layer 82 (not shown) of the same color and spaced apart from the tunnel insulating layer 82 by a predetermined distance. A lower layer film 92 of a stripe-shaped scanning signal wiring 9 extending in a direction orthogonal to the wiring 8 is formed. The lower layer film 92 has a substantially rectangular cross section perpendicular to the extending direction. Etching in this processing uses, for example, a wet etching method with a mixed aqueous solution of phosphoric acid, acetic acid, and nitric acid.

  Constructing this lower layer film 92 with aluminum exhibits low resistance, and by adjusting the ratio of phosphoric acid, acetic acid, and nitric acid in the etching solution, specifically, by increasing the ratio of nitric acid, By reducing the adhesiveness, processing is easy, and it is preferable as a scanning signal wiring material.

  Next, as shown in FIG. 13, an opening reaching the surface of the field insulating film 81 is formed in the interlayer insulating film 14 and the second insulating film 24. In this, the openings 14a and 24a having a substantially rectangular plane and a substantially bowl shape in the depth direction are formed substantially concentrically. This drilling can be performed by photolithography. This opening position is within the line width of the video signal wiring 8 and between the one side wall 92a of the lower layer film 92 and the tunnel insulating layer 82. Each opening has a taper on the side wall and has a continuous taper in the laminated state. It is configured to be handled as a single opening substantially. In addition, the shape of the taper and the film boundary part is such that the metal film laminated on the upper part is less likely to cause step breakage in the part.

  Subsequently, as shown in FIG. 14, an aluminum alloy film 93 mainly composed of aluminum is formed on the entire upper surface such as the lower layer film 92 and the opening. The aluminum alloy film 93 is an aluminum-neodymium film doped with 2 atomic% of neodymium (Nd) described above, and is formed by sputtering.

  After the film formation, it is processed by a photoetching process as shown in FIG. 15, and the upper layer of the scanning signal wiring 9 is continuously extended from the upper surface 92b of the lower layer film 92 through one side wall 92a to a part of the opening 14a and the opening 24a. A film 94 was laminated.

  On the other hand, the other side wall 92c side of the lower layer film 92 is configured such that the upper layer film 94 does not remain from a part of the upper surface to the side wall in consideration of the element isolation described above. Therefore, the second insulating film 24 also exposes the intermediate portion 24b extending from the outer portion of the side wall 92c to the adjacent scanning signal wiring (not shown) side. The scanning signal wiring 9 is constituted by a laminated film of the upper layer film 94 made of the aluminum alloy film and the lower layer film 92 made of the aluminum film.

  On the other hand, when forming the scanning signal wiring 9 with the laminated structure of the aluminum alloy film, the specific resistance of the aluminum alloy film constituting the lower layer film 92 is made smaller than the specific resistance of the aluminum alloy film constituting the upper layer film 94. To do.

Next, selective dry etching of Si of the second insulating film 24 is performed. This selective dry etching of Si is performed using a mixed gas of CF ₄ and O ₂ or a mixed gas of SF ₆ and O ₂ . These gases etch both Si and SiN. However, by optimizing the ratio of O ₂ , the Si etching selectivity can be increased.

  By this dry etching method, as shown in FIG. 16, a part of the second insulating film 24 made of Si disposed on the interlayer insulating film 14 made of SiN is selectively removed. By this selective dry etching of Si, the exposed portion including the intermediate portion 24b is removed. Further, in addition to this, a part of the intermediate portion 24b following the lower layer film 92 is removed by side etching, and the lower layer film 92 has a bowl shape, and this portion becomes the undercut portion 25.

Next, as shown in FIG. 17, the interlayer insulating film 14 is processed, the interlayer insulating film 14 on the tunnel insulating layer 82 is removed, and the tunnel insulating layer 82 is exposed. Etching can be performed by dry etching using, for example, an etchant mainly composed of CF ₄ or SF ₆ .

  Next, the upper electrode 26 is formed as shown in FIG. As this film formation method, for example, a sputtering method is used. As the upper electrode 26, for example, a laminated film of Ir / Pt / Au is used, and the film thickness is, for example, about 3 nm. The upper electrode 26 is formed so as to continuously cover the field insulating film 81 and the upper layer film 94 from the tunnel insulating layer 82, and is separated from the adjacent scanning signal wiring (not shown) by the undercut portion 25. ing. Through the above steps, the scanning signal wiring 9, the video signal wiring 8, the electron source 10, and the upper electrode 26 on the back substrate 1 are formed.

  In this embodiment, the scanning signal wiring is different in shape between the edge on the conductive side and the edge on the non-conductive side, and the cross-sectional shape in the thickness direction is asymmetrical on the left and right of the central axis of the line. ing. The scanning signal wiring has a tapered shape at the conductive edge, and the second insulating film is recessed by side etching at the opposite non-conductive edge, and the scanning signal wiring has a hook shape. Due to the difference in edge shape, the upper electrode is continuously formed from the scanning signal wiring to the electron source at the conduction side edge, whereas the upper electrode is divided at the undercut portion at the non-conduction side edge part, and adjacent electrons The element is separated from the source.

  According to such a manufacturing process, the first video signal wiring lead terminal 811 as the lower layer film is formed before the processing of the video signal wiring 8, and then the video signal wiring 8 and the second video signal wiring lead terminal 812 are formed. By forming the video signal wiring lead terminal 8a having a two-layer film structure, even if the disconnection S occurs in the first video signal wiring lead terminal 811 of the lower layer film, the second video signal wiring lead of the upper layer film is formed. It is electrically coupled by the terminal 812. Therefore, disconnection of the video signal wiring lead terminal 8a can be prevented beforehand.

  In the above-described method of forming the video signal wiring lead terminal 8a, the first video signal wiring lead terminal 811 as a lower layer film is formed in advance before the processing of the video signal wiring 8, and the second time when the video signal wiring 8 is processed. The video signal wiring lead terminal 812 is formed at the same time. However, as another forming method, the video signal wiring 8 and the first video signal wiring lead terminal 811 are processed in the same process, and then the scanning signal wiring is formed. 9 and the scanning signal wiring lead terminal 9a, the second video signal wiring lead terminal 812 is formed at the same time, whereby the video signal wiring lead terminal 8a having a two-layer structure can be formed.

  According to such a manufacturing process, the second video signal wiring lead terminal 812 is processed simultaneously with the processing of the scanning signal wiring 9 and the scanning signal wiring lead terminal 9a to form the video signal wiring lead terminal 8a having a two-layer film structure. As a result, the disconnection S generated during processing of the video signal wiring 8, the first video signal wiring lead terminal 811, the scanning signal wiring 9, and the scanning signal wiring lead terminal 9a can be repaired and recovered.

  In the above embodiment, the structure using the MIM type as the electron source is taken as an example, but the present invention is not limited to this, and the self-luminous FPD using the various electron sources described above is not limited thereto. Can be applied similarly.

  Moreover, in the said Example, although neodymium was illustrated as an aluminum alloy, it is not limited to this, A various other thing is used if necessary as a metal for alloys.

  FIG. 19 is an explanatory diagram of an example of an equivalent circuit of an image display device to which the configuration of the present invention is applied. In FIG. 19, an area indicated by a broken line is a display area 6, and n video signal wirings 8 and m scanning signal wirings 9 are arranged in the display area 6 so as to cross each other, and an n × m matrix. Is formed. Each intersection of the matrix constitutes a sub-pixel, and one group of three unit pixels (or sub-pixels) “R”, “G”, and “B” in the figure constitutes one color pixel. The configuration of the electron source is not shown. The video signal wiring (cathode wiring) 8 is connected to the video signal driving circuit DDR at the video signal wiring lead terminal 8a, and the scanning signal wiring (gate wiring) 9 is connected to the scanning signal driving circuit SDR at the scanning signal wiring lead terminal 9a. ing. The video signal NS is input from the external signal source to the video signal driving circuit DDR, and the scanning signal SS is similarly input to the scanning signal driving circuit SDR.

  Thus, a two-dimensional full-color image can be displayed by supplying the video signal NS to the video signal wiring 8 that intersects the scanning signal wiring 9 that is sequentially selected. By using the display panel of this configuration example, an image display apparatus with a relatively low voltage and high efficiency is realized.

1A and 1B are diagrams for explaining an embodiment of an image display device of the present invention, in which FIG. 1A is a plan view seen from the front substrate side, and FIG. 1B is a view seen from direction A in FIG. FIG. FIG. 2 is a schematic plan view of a back substrate shown by removing the front substrate of FIG. 1. FIG. 3 is a schematic cross-sectional view of a back substrate taken along line B-B in FIG. 2 and a schematic cross-sectional view of a front substrate corresponding to the back substrate. FIG. 3 is a schematic cross-sectional view of a back substrate along the line CC in FIG. 2 and a schematic cross-sectional view of a front substrate corresponding to the back substrate. FIG. 3 is a schematic cross-sectional view of a back substrate along a line DD in FIG. 2 and a schematic cross-sectional view of a front substrate corresponding to the back substrate. It is a principal part schematic top view which shows the structure of the video signal wiring terminal part of the back substrate shown in FIG. 7A and 7B are schematic views for explaining a manufacturing process of the image display device according to the present invention, in which FIG. 7A is a plan view, FIG. 7B is a cross-sectional view taken along line CC in FIG. (c) is sectional drawing which follows the DD line | wire of Fig.7 (a). FIGS. 8A and 8B are schematic views for explaining a manufacturing process of an image display device according to the present invention, FIG. 8A is a plan view, FIG. 8B is a cross-sectional view taken along line CC in FIG. (c) is sectional drawing which follows the DD line | wire of Fig.8 (a). 9A and 9B are schematic views for explaining a manufacturing process of the image display device according to the present invention, in which FIG. 9A is a plan view, FIG. 9B is a cross-sectional view taken along line CC in FIG. (c) is sectional drawing which follows the DD line | wire of Fig.9 (a). FIGS. 10A and 10B are schematic views for explaining a manufacturing process of an image display device according to the present invention, in which FIG. 10A is a plan view, FIG. 10B is a cross-sectional view taken along line CC in FIG. FIG. 10C is a cross-sectional view taken along the line DD in FIG. 11A and 11B are schematic views for explaining a manufacturing process of the image display device according to the present invention, in which FIG. 11A is a plan view, FIG. 11B is a cross-sectional view taken along line CC in FIG. (c) is sectional drawing which follows the DD line | wire of Fig.11 (a). 12A and 12B are schematic views for explaining a manufacturing process of the image display device according to the present invention, in which FIG. 12A is a plan view, FIG. 12B is a cross-sectional view taken along the line CC in FIG. FIG. 12C is a cross-sectional view taken along the line DD in FIG. FIGS. 13A and 13B are schematic views for explaining a manufacturing process of the image display device according to the present invention, FIG. 13A is a plan view, FIG. 13B is a cross-sectional view taken along line CC in FIG. FIG. 13C is a cross-sectional view taken along the line DD in FIG. FIGS. 14A and 14B are schematic views for explaining a manufacturing process of an image display device according to the present invention, in which FIG. 14A is a plan view, FIG. 14B is a cross-sectional view taken along line CC in FIG. (c) is sectional drawing which follows the DD line | wire of Fig.14 (a). FIGS. 15A and 15B are schematic views for explaining a manufacturing process of an image display device according to the present invention, in which FIG. 15A is a plan view, FIG. 15B is a cross-sectional view taken along line CC in FIG. (c) is sectional drawing which follows the DD line | wire of Fig.15 (a). FIGS. 16A and 16B are schematic views for explaining a manufacturing process of an image display device according to the present invention, FIG. 16A is a plan view, FIG. 16B is a cross-sectional view taken along line CC in FIG. (c) is sectional drawing which follows the DD line | wire of Fig.16 (a). FIGS. 17A and 17B are schematic views for explaining a manufacturing process of an image display device according to the present invention, FIG. 17A is a plan view, FIG. 17B is a cross-sectional view taken along line CC in FIG. FIG. 17C is a cross-sectional view taken along the line DD in FIG. FIG. 18A is a schematic diagram for explaining a manufacturing process of an image display device according to the present invention, FIG. 18A is a plan view, FIG. 18B is a cross-sectional view taken along line CC in FIG. FIG. 18C is a cross-sectional view taken along the line DD in FIG. It is explanatory drawing of the equivalent circuit example of the image display apparatus to which the structure of this invention is applied. It is a principal part schematic top view which shows the disconnection structure which arose in the video signal wiring terminal part of the back substrate.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Back substrate, 2 ... Front substrate, 3 ... Frame body, 4 ... Exhaust pipe, 5 ... Sealing member, 51 ... Sealing area, 6 ... Display area 7 through hole 8 image signal electrode 8a image signal electrode lead terminal 811 first video signal electrode lead terminal 812 second video signal electrode lead Terminals 82... Internal electrode portions 83... Sealing electrode portions 9... Scanning signal electrodes 9 a... Scanning signal electrode lead terminals 92. Stop electrode part, 10 ... Electron source, 11 ... Connection electrode, 12 ... Spacing member, 13 ... Adhesive member, 14 ... Interlayer insulating film, 15 ... Phosphor layer, 16 BM film, 17 Metal back (anode electrode), S Disconnection, TAO Tunnel insulation film.

Claims (16)

A plurality of video signal wires extending in one direction and juxtaposed in the other direction intersecting the one direction, and a plurality of video signal wires extending in the other direction and juxtaposed in the one direction so as to cross the video signal wire Scanning signal wiring, an interlayer insulating film disposed between the scanning signal wiring and the video signal wiring, and provided near the intersection of the video signal wiring and the scanning signal wiring and connected to the scanning signal wiring. A back substrate with an electron source,
A front substrate comprising a phosphor layer provided corresponding to the electron source, and an anode for applying an accelerating voltage so as to direct electrons emitted from the electron source to the phosphor layer;
A frame that is inserted around the display area between the front substrate and the back substrate, and holds a predetermined distance between the front substrate and the back substrate;
A sealing member that hermetically seals the frame, the front substrate, and the back substrate;
Comprising
At least one end of the video signal wiring has a video signal wiring lead terminal drawn out from the display region through a sealing region where the rear substrate and the frame body face each other,
At least one end of the scanning signal wiring has a scanning signal wiring lead terminal that is led out from the display region through a sealing region where the back substrate and the frame face each other,
The image display device, wherein the video signal wiring lead terminal has a plurality of laminated film structures.   The image display device according to claim 1, wherein the laminated film structure is a laminated film of an aluminum film and an aluminum alloy film containing aluminum as a main component.   3. The image display device according to claim 2, wherein the laminated film structure is a two-layer film structure in which the aluminum film is disposed in a lower layer and an aluminum alloy film mainly composed of aluminum is laminated on the upper layer. .   4. The image display device according to claim 2, wherein in the laminated film structure, the film thickness of the aluminum film is larger than the film thickness of the aluminum alloy film.   2. The image display device according to claim 1, wherein the laminated film structure is a laminated film of an aluminum-neodymium alloy film mainly composed of aluminum and an iridium-platinum-gold alloy film.   The electron source has a lower electrode and an upper electrode, and an electron acceleration layer sandwiched between the lower electrode and the upper electrode, and a voltage is applied between the lower electrode and the upper electrode to 6. The image display device according to claim 1, wherein the image display device is a thin-film electron source array that emits electrons.   The image display device according to claim 1, wherein the electron source is an electron-emitting device including a conductive film having an electron-emitting portion. A plurality of video signal wirings extending in one direction and juxtaposed in the other direction intersecting the one direction, and extending in the other direction and intersecting the video signal wirings and juxtaposed in the one direction A plurality of scanning signal wirings, an interlayer insulating film disposed between the scanning signal wirings and the video signal wirings, and the scanning signal wirings provided in the vicinity of intersections of the video signal wirings and the scanning signal wirings. A back substrate with a connected electron source;
A front substrate comprising a phosphor layer provided corresponding to the electron source and an anode for applying an acceleration voltage for directing electrons emitted from the electron source to the phosphor layer;
A frame disposed between the front substrate and the rear substrate and holding the two substrates at a predetermined interval;
A plurality of spacing members disposed in the display area between the front substrate and the back substrate;
An adhesive member that bonds the end face of the spacing member to the front substrate and the rear substrate;
A sealing member that hermetically seals the end face of the frame body and the front substrate and the rear substrate in a sealing region;
Comprising
At least one end of the video signal wiring has a video signal wiring lead terminal drawn out from the display region through a sealing region where the rear substrate and the frame body face each other,
At least one end of the scanning signal wiring has a scanning signal wiring lead terminal that is led out from the display region through a sealing region where the back substrate and the frame face each other,
The image display device, wherein the video signal wiring lead terminal has a plurality of laminated film structures.   9. The image display device according to claim 8, wherein the laminated film structure is a laminated film of an aluminum film and an aluminum alloy film containing aluminum as a main component.   10. The image display device according to claim 9, wherein the laminated film structure is a two-layer film structure in which the aluminum film is disposed in a lower layer and an aluminum alloy film mainly composed of aluminum is laminated on the upper layer. .   12. The image display device according to claim 10, wherein the laminated film structure has a film thickness of the aluminum film larger than a film thickness of the aluminum alloy film.   9. The image display device according to claim 8, wherein the laminated film structure is a laminated film of an aluminum-neodymium alloy film mainly composed of aluminum and an iridium-platinum-gold alloy film.   13. The image display according to claim 8, wherein the interval holding member is disposed so as to overlap with the scanning signal wiring and extend in the same direction as the scanning signal wiring. apparatus.   The electron source has a lower electrode, an upper electrode, and an electron acceleration layer sandwiched between the lower electrode and the upper electrode, and a voltage is applied between the lower electrode and the electrode to apply the upper electrode 14. The image display device according to claim 8, wherein the image display device is a thin film electron source array that emits electrons from an electrode.   The image display device according to claim 8, wherein the electron source is an electron-emitting device including a conductive film having an electron-emitting portion.   The image display device according to claim 8, wherein the electron source includes at least a carbon nanotube.

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