JP2006202531A - Image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress voltage drop of a signal electrode and suppress generation of degradation in the degree of vacuum caused by a lead-out terminal for penetrating through an airtight sealing part by an image display device in which a display region surrounded by a support body is made to have a vacuum atmosphere because a video signal electrode having the lead-out terminal on the end part and a scanning signal electrode similarly having the lead-out terminal on the end part are arranged in a matrix shape via an insulating membrane, and because the rear face substrate in which an electron source has been arranged in the vicinity of intersection part of both electrodes, and the front face substrate which has a phosphor layer and an anode are airtightly sealed by a sealing member via the support body which becomes a sealing frame. <P>SOLUTION: The electrode thickness Ts of sealing electrode parts 83, 93 arranged in a sealing region 51 which is the airtight sealing part of the video signal electrode 8 and/or the scanning signal electrode 9 has been made thinner than the electrode thickness Tin of the inner electrode parts 82, 92 in a vacuum display region 6. <P>COPYRIGHT: (C)2006,JPO&NCIPI

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 back substrate.

  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 broadcasts, there is an increasing demand for flat image display devices (flat panel displays, FPDs) that have high luminance 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. Further, in particular, as a self-luminous display device utilizing electron emission from an electron source to a vacuum, what is called an electron emission type image display device or a field emission type image display device, as that capable of increasing the brightness, Various flat-type image display devices such as an organic EL display characterized by low 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 spint type, surface conduction type, carbon nanotube type, metal-insulator-metal laminated MIM (Metal-Insulator-Metal) type, metal- An MIS (Metal-Insulator-Semiconductor) type in which an insulator and a semiconductor are stacked, or a thin film type electron source such as a metal-insulator-semiconductor-metal type is used.

  As the MIM type electron source, those disclosed in, for example, Patent Document 1 and Patent Document 2 are known. The metal-insulator-semiconductor type electron source reported in Non-Patent Document 1 is the MOS type, and the metal-insulator-semiconductor-metal type electron source is reported in Non-Patent Document 2 and other HEED type electrons. As a source, an EL type electron source reported in Non-Patent Document 3 and the like, a porous silicon type electron source reported in Non-Patent Document 4 and the like are known.

  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. 2. Description of the Related Art There is known a display panel that includes a front substrate and a support that serves as a sealing frame that seals the opposing internal space of both substrates in a predetermined vacuum state. The display panel is operated in combination with a drive circuit.

  In an image display device having an MIM type electron source, a large number of first electrodes (for example, cathode electrodes, image signal electrodes) arranged in parallel in a second direction extending in the first direction and intersecting the first direction. ), An insulating film formed to cover the first electrode, and a plurality of second electrodes (for example, extending in the second direction on the insulating film and arranged in parallel in the first direction) A back substrate having a gate electrode, a scanning signal electrode), and an electron source provided in the vicinity of the intersection of the first electrode and the second electrode, the back substrate having a substrate made of an insulating material, The electrode is formed on the substrate.

  With this configuration, scanning signals are sequentially applied to the scanning signal electrodes in the other direction. On the substrate, the electron source is provided at each intersection of the scanning signal electrode and the image signal electrode. These electrodes and the electron source are connected to each other by a feeding electrode, and a current is supplied to the electron source. Opposite to the rear substrate, a front substrate having a plurality of color phosphor layers and a third electrode (anode electrode, anode) on the opposing inner surface is provided. The front substrate is formed of a light transmissive material suitable for glass. And the support body used as a sealing frame is inserted and sealed to the bonding inner periphery of both board | substrates, and the inside formed with the said back substrate, a front substrate, and a support body is comprised in vacuum.

  The electron source is located at the intersection of the first electrode and the second electrode as described above, and the amount of electrons emitted from the electron source (including emission on / off) due to the potential difference between the first electrode and the second electrode. ) To 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 body between the rear substrate and the front substrate. The distance between the two 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 this fixed 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, 10 ⁻⁵ to 10 ⁻⁷ Torr.

A first electrode lead terminal connected to the first electrode formed on the rear substrate and a second electrode lead terminal connected to the second electrode penetrate through the sealing region between the support and both substrates. In general, a support serving as a sealing frame is fixed to the rear substrate and the front substrate with a sealing member such as frit glass. The first electrode lead terminal and the second electrode lead terminal are led out through a sealing region which is an airtight attachment portion between the sealing frame and the rear substrate. Patent Document 3 discloses an image forming apparatus having a structure bent at a lower portion of a support frame at a portion where an electrode wiring is taken out to the outside.
JP-A-7-65710 Japanese Patent Laid-Open No. 10-153979 JP-A-9-277586 j. Vac. Sci. Techonol. B11 (2) p. 429-432 (1993) high-efficiency-electro-emission device, Jpn. J. et al. Appl. Phys. vol36, pL939 Electroluminescence, Applied Physics Vol. 63, No. 6, p. 592 Applied Physics Vol. 66, No. 5, p. 437

  The first electrode and the second electrode are disposed on the back substrate, and the lead terminals are led out through the gap between the back substrate surface and the support end surface. A sealing member such as frit glass is disposed in the gap and hermetically sealed to form a sealed region. In such a configuration, in order to obtain a display image having a desired brightness, it is necessary to supply a large amount of current to the electrode, particularly the scanning signal electrode of the second electrode, and along with the scanning signal electrode, it is accompanied. Voltage drop.

  In order to solve this problem, it is necessary to reduce the electrical resistance of the scanning signal electrode in order to reduce the voltage drop. The scanning signal electrode is composed of a thin film of a metal material such as Al (aluminum), for example. In order to reduce the electric resistance, it is necessary to increase (thicken) the thickness of the metal thin film constituting the electrode. . However, when the film thickness is increased, the stress of the electrode (wiring) increases, and there is a problem that it is easily peeled off from the back substrate. This problem is the same in the configuration of Patent Document 1.

  In particular, in the sealing region where the stress in the peeling direction is likely to occur, that is, in the hermetic adhesion portion in the gap between the back substrate surface and the support end surface, there is a high possibility of peeling. ) Will cause a vacuum leak. The occurrence of the vacuum leak causes deterioration of the degree of vacuum in the vacuum display region, and there is a problem that the reliability of the image display device is impaired.

  An object of the present invention is to provide a reliable and long-life image display device by suppressing the generation of stress of an electrode in a sealing region to prevent the occurrence of vacuum leak.

  In order to achieve the above object, in the present invention, the electrode thickness disposed in the sealing region is set to be thinner than the electrode thickness in the display region. A self-luminous flat display device is configured by incorporating an image signal driving circuit, a scanning signal driving circuit, and other peripheral circuits into the image display device having the above configuration.

  According to the first aspect of the present invention, it is possible to suppress the generation of the stress of the electrode in the sealing region to prevent the occurrence of the vacuum leak and to obtain a reliable and long-life image display device.

According to the second aspect of the present invention, it is possible to suppress the generation of the stress of the wiring in the sealing region to prevent the occurrence of the vacuum leak, and to obtain a reliable and long-life image display apparatus.
In addition, the electrodes can be easily formed.

  According to the invention of claim 3, the electrode material in the sealing region and the electrode material in the display region can be arbitrarily selected, and the generation of the stress of the electrode in the sealing region is suppressed to prevent the occurrence of vacuum leak. At the same time, it is possible to obtain an image display device with high reliability and long life, which has the effect of improving the electrical characteristics in the vacuum display region.

  According to the fourth aspect of the present invention, the electrode lead terminals of the first and second electrodes can be formed at the same time, and the work efficiency can be improved and an inexpensive image display apparatus can be obtained.

  According to the fifth aspect of the invention, it is possible to suppress the generation of the stress of the electrode in the sealing region to prevent the occurrence of the vacuum leak, and to obtain a reliable and long-life image display apparatus.

  According to the sixth aspect of the present invention, the electrode thickness is larger than that of the video signal electrode, and the effect is remarkable, and the generation of the vacuum stress is prevented by suppressing the generation of the stress of the electrode in the sealing region. A reliable and long-life image display device can be obtained.

  According to the invention of claim 7, electrical characteristics can be ensured.

  According to the inventions according to claims 8 to 10, the characteristics of each electron source can be effectively used, and a reliable and long-life image display apparatus can be obtained.

  According to the eleventh aspect of the invention, the distance between the two substrates can be ensured to a desired value in cooperation with the support, and a highly reliable image display apparatus with a long life can be obtained.

  According to the twelfth aspect of the present invention, damage to electrodes such as an electron source and an image signal electrode can be prevented.

According to the thirteenth aspect of the present invention, it is possible to suppress the generation of the stress of the wiring in the sealing region to prevent the occurrence of the vacuum leak, and to obtain a reliable and long-life image display device.
In addition, the electrodes can be easily formed.

  According to the fourteenth aspect of the present invention, the electrode material in the sealing region and the electrode material in the display region can be arbitrarily selected, and the generation of the stress of the electrode in the sealing region is suppressed to prevent the occurrence of vacuum leak. In addition, it is possible to obtain a reliable and long-life image display device that has the effect of improving the electrical characteristics in the vacuum display region.

  According to the fifteenth aspect of the present invention, the electrode lead terminals of the first and second electrodes can be formed at the same time, and the work efficiency can be improved and an inexpensive image display apparatus can be obtained.

  According to the sixteenth aspect of the present invention, it is possible to prevent the generation of vacuum leak by suppressing the generation of stress of the electrode in the sealing region, and to obtain a reliable and long-life image display apparatus.

  According to the seventeenth aspect of the present invention, the electrode thickness is larger than that of the video signal electrode, and the effect is remarkable, and the generation of vacuum stress is prevented by suppressing the generation of stress of the electrode in the sealing region. A reliable and long-life image display device can be obtained.

  According to the invention of claim 18, electrical characteristics can be ensured.

  According to the nineteenth to twenty-first aspects of the present invention, it is possible to effectively utilize the features of each electron source, and to obtain a reliable and long-life image display apparatus.

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

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

  1 to 4, reference numeral 1 is a rear substrate, 2 is a front substrate, and both the substrates 1 and 2 are made of a glass plate having a thickness of several millimeters, for example, about 3 mm. Reference numeral 3 denotes a support, and the support 3 is made of a glass plate or a frit glass sintered body having a thickness of several mm, for example, about 3 mm. An exhaust pipe 4 is fixed to the back substrate 1. The support 3 is inserted around the periphery of the substrates 1 and 2 and hermetically sealed with the substrates 1 and 2 via a sealing member 5 such as frit glass.

A space surrounded by the support 3, both the substrates 1 and 2 and the sealing member 5 is evacuated through the exhaust pipe 4 to form a display region 6 while maintaining a vacuum of 10 ⁻³ to 10 ⁻⁷ Pa, for example. is doing. The exhaust pipe 4 is attached to the outer surface of the rear substrate 1 as described above and communicates with the through hole 7 formed through the rear substrate 1. After the exhaust is completed, the exhaust pipe 4 is Sealed.

  Reference numeral 8 denotes a video signal electrode. The video signal electrode 8 extends in one direction (Y direction) on the inner surface of the rear substrate 1 and is arranged in parallel in the other direction (X direction). This video signal electrode 8 has a video signal electrode lead-out terminal 81 at one end, and the tip of this terminal airtightly penetrates a sealing region 51 which is a hermetically sealed portion between the support 3 and the back substrate 1. Extending to the end of the substrate 1.

  Reference numeral 9 denotes a scanning signal electrode. The scanning signal electrode 9 extends on the video signal electrode 8 in the other direction (X direction) intersecting with the scanning signal electrode 8 and is arranged in parallel in the one direction (Y direction). . The scanning signal electrode 9 has a scanning signal electrode lead-out terminal 91 at one end, and the tip of the terminal penetrates the sealing region 51 which is a hermetically sealed portion between the support 3 and the back substrate 1 in an airtight manner. And extend to the other end of the substrate 1.

  The scanning signal electrode 9 includes an electrode thickness Tin of an internal electrode portion 92 disposed in the vacuum display region 6 and a sealing electrode portion in a portion that airtightly penetrates the sealing region 51 of the scanning signal electrode lead terminal 91. The electrode thickness Ts of 93 is such that Ts <Tin. The thicknesses of Ts and Tin are first set as thin as possible so as to reduce the generation of stress since Ts is arranged in the sealing region, while Tin is thickened so as to reduce the voltage drop. Set.

  Reference numeral 10 denotes an electron source, and the electron source 10 is provided at each intersection of the scanning signal electrode 9 and the video signal electrode 8, and the electron source 10 is connected to the scanning signal electrode 9, the video signal electrode 8, and the connection electrode. 11 and 11A, respectively. An interlayer insulating film INS is disposed between the video signal electrode 8 and the electron source 10 and the scanning signal electrode 9.

  Here, for example, an Al / Nd film is used as the video signal electrode 8, and an Ir / Pt / Au film is used as the scanning signal electrode 9, for example. The electrode lead terminals 81 and 91 are provided only at one end of the electrode, but may be provided at both ends.

  Next, reference numeral 12 denotes a spacer, which is made of a ceramic material, and is shaped into a rectangular thin plate shape. In this embodiment, every other spacer is arranged upright on the scanning signal electrode 9, and an adhesive member. 13 is fixed to both substrates 1 and 2. The spacer 12 is usually installed 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 support 3, the substrate material, the spacer arrangement interval, the spacer material, etc. In general, the height is substantially the same as the support 3 described above, A practical value is a thickness of several tens of μm to several mm or less, and a length of about 20 mm to 200 mm, preferably about 80 mm to 120 mm.
The spacer 12 has a resistance value of about 10 ⁸ to 10 ⁹ Ω · cm.

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

These phosphors include, for example, Y ₂ O ₂ S: Eu (P22-R) as red, ZnS: Cu, Al (P22-G) as green, and ZnS: Ag, Cl (P22-B) as blue. Can be used. With this phosphor screen configuration, 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 color 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 electrode 9 and is divided for each pixel column.

  With the configuration of Example 1, it is possible to prevent the occurrence of vacuum leak by suppressing the generation of stress of the electrode in the sealing region, and also to suppress the voltage drop, and have a long life with high reliability. An image display device can be obtained.

  FIG. 5 is a schematic cross-sectional view corresponding to FIG. 4 showing another embodiment of the image display apparatus of the present invention. In FIG. 5, the scanning signal electrode 9 has a laminated structure of internal electrode portions 92 disposed in the vacuum display region 6. That is, the first internal electrode portion 921 made of the same material as the scanning signal electrode lead terminal 91, for example, Cr, and disposed on the lower layer side, and the second internal electrode portion made of a different material, for example, Al, laminated on the upper layer thereof. 922 has a stacked structure. Of course, the relationship between the electrode thickness Ts of the sealing electrode portion 93 that penetrates the sealing region 51 in an airtight manner and the thickness Tin of the internal electrode portion 92 is Ts <Tin. Further, the film thicknesses of the first internal electrode portion 921 and the second internal electrode portion 922 may be the same or different dimensions.

  With the configuration of the second embodiment, in addition to the same excellent effects as the first embodiment described above, the selection range of the material of the second internal electrode portion 922 used for the portion exposed in the vacuum display region 6 Has the effect of spreading.

FIG. 6 shows still another embodiment of the image display device of the present invention, FIG. 6 (a) is a schematic sectional view corresponding to FIG. 4, and FIG. 6 (b) is a plan view of the main part of FIG. The same parts as those in the above-mentioned figure are given the same symbols. 6A and 6B, the scanning signal electrode 9 includes an internal electrode portion 92 disposed in the vacuum display region 6 and a sealing electrode portion 93 that penetrates the sealing region 51 in an airtight manner. In this configuration, the scanning signal electrode lead terminal 91 is connected by a projection 923 through an opening provided in the insulating film INS.

  With the configuration of the third embodiment, the same effect as the first and second embodiments described above can be obtained, and the sealing electrode in a portion that airtightly penetrates the sealing region 51 when the video signal electrode 8 is formed. The scanning signal electrode lead terminal 91 having the portion 93 can be formed at the same time and with the same material, so that the work efficiency of electrode formation can be improved and the hermetic sealing in the hermetic sealing process performed using the sealing member 5 is performed. The wearing conditions are further simplified, and the occurrence of vacuum leak can be further suppressed.

  FIG. 7 is a schematic cross-sectional view of the back substrate along the line DD of FIG. 2 showing still another embodiment of the image display device of the present invention, and a schematic cross-sectional view of the front substrate corresponding to the back substrate. The same parts as those in the previous figure are given the same symbols. In FIG. 7, the video signal electrode 8 is sealed at a portion of the internal electrode portion 82 disposed in the vacuum display region 6 and the portion of the video signal electrode lead-out terminal 81 that penetrates the sealing region 51 in an airtight manner. The electrode thickness Ts of the stop electrode portion 83 has a configuration of Ts <Tin. The thicknesses of Ts and Tin are set as thin as possible so as to reduce the generation of stress since Ts is first arranged in the sealing region, while Tin is thickened so as to reduce the voltage drop. Set.

  With the configuration of this Example 4, it is possible to suppress the generation of vacuum stress by suppressing the generation of stress of the electrode in the sealing region, and to suppress the voltage drop, and to achieve a long life with high reliability. An image display device can be obtained.

  8A and 8B are diagrams for explaining an example of the electron source 10 constituting the pixel of the image display device of the present invention. FIG. 8A is a plan view, and FIG. 8B is an E-line in FIG. FIG. 8C is a cross-sectional view taken along the line FF in FIG. 8A. This electron source is a MIM electron source.

  The structure of this electron source will be described in the manufacturing process. First, the lower electrode DED (the video signal electrode 8 in each of the above embodiments), the protective insulating layer INS1, and the insulating layer INS2 are formed on the back substrate SUB1. Next, a metal film serving as a spacer electrode for arranging the interlayer film INS3, the upper bus electrode AED (scanning signal electrode 9 in each of the above-described embodiments) serving as a power supply line to the upper electrode AED, and the spacer 12, for example, A film is formed by sputtering or the like. Aluminum can be used for the lower electrode and the upper electrode, but other metals described later can also be used.

  As the interlayer film INS3, for example, silicon oxide, silicon nitride film, silicon, or the like can be used. Here, a silicon nitride film is used and the film thickness is 100 nm. When the protective insulating layer INS1 formed by anodic oxidation has a pinhole, the interlayer film INS3 fills the defect, and the upper bus electrode (metal film lower layer MDL and metal film upper layer MAL that becomes the lower electrode DED and the scanning signal electrode) The metal film intermediate layer MML plays a role of maintaining the insulation between the three laminated films sandwiching Cu.

  Note that the upper bus electrode AED is not limited to the above three-layer laminated film, and may be more than that. For example, as the metal film lower layer MDL and the metal film upper layer MAL, a metal material having high oxidation resistance such as Al, chromium (Cr), tungsten (W), molybdenum (Mo), an alloy containing them, or a laminated film thereof is used. be able to. Here, an Al—Nd alloy was used as the metal film lower layer MDL and the metal film upper layer MAL. In addition, a metal film intermediate layer MML is formed by using an Al alloy and a laminated film of Cr, W, Mo, etc. as the metal film lower layer MDL and using a laminated film of Cr, W, Mo, etc. and an Al alloy as the metal film upper layer MAL. By using a five-layer film in which the film in contact with Cu is a refractory metal, the refractory metal becomes a barrier film during the heating process in the manufacturing process of the image display device, and alloying of Al and Cu can be suppressed. Therefore, it is particularly effective for reducing the resistance.

  When only the Al—Nd alloy is used, the film thickness of the Al—Nd alloy is made as thick as possible in order to make the metal film upper layer MAL thicker than the metal film lower layer MDL and to reduce the wiring resistance of the metal film intermediate layer MML. Keep it. Here, the metal film lower layer MDL is 300 nm, the metal film intermediate layer MML is 4 μm, and the metal film upper layer MAL is 450 nm. Note that Cu in the metal film intermediate layer MML can be formed by electroplating or the like in addition to sputtering.

  In the case of the above-mentioned five-layer film using a refractory metal, a multilayer film in which Cu is sandwiched between Mo that can be wet-etched with a mixed aqueous solution of phosphoric acid, acetic acid and nitric acid is used as the metal film intermediate layer MML. Is particularly effective. In this case, the film thickness of Mo sandwiching Cu is 50 nm, the Al alloy of the metal film lower layer MDL sandwiching the metal film intermediate layer is 300 nm, and the Al alloy of the metal film upper layer MAL is 50 nm.

  Subsequently, the metal film upper layer MAL is processed into a stripe shape intersecting with the lower electrode DED by patterning a resist by screen printing and etching. In this etching process, for example, wet etching using a mixed aqueous solution of phosphoric acid and acetic acid is used. By not adding nitric acid to the etching solution, it is possible to selectively etch only the Al—Nd alloy without etching Cu.

  Even in the case of a five-layer film using Mo, it is possible to selectively etch only the Al—Nd alloy without etching Mo and Cu by not adding nitric acid to the etching solution. Although one metal film upper layer MAL is formed per pixel here, two metal film upper layers MAL may be formed.

  Subsequently, the same resist film is used as it is, or Cu of the metal film intermediate layer MML is wet-etched with a mixed aqueous solution of phosphoric acid, acetic acid and nitric acid, for example, using the Al—Nd alloy of the metal film upper layer MAL as a mask. Since the etching rate of Cu in an etching solution of a mixed aqueous solution of phosphoric acid, acetic acid, and nitric acid is sufficiently higher than that of an Al—Nd alloy, only Cu in the metal film intermediate layer MML can be selectively etched. . Even in the case of a five-layer film using Mo, the etching rate of Mo and Cu is sufficiently higher than that of an Al—Nd alloy, and it is possible to selectively etch only the three-layered film of Mo and Cu. Other ammonium persulfate aqueous solutions and sodium persulfate aqueous solutions are also effective for etching Cu.

  Subsequently, the metal film lower layer MDL is processed into a stripe shape intersecting with the lower electrode DED by resist patterning and etching by screen printing. This etching process is performed by wet etching with a mixed aqueous solution of phosphoric acid and acetic acid. At that time, by shifting the position of the resist film to be printed in a direction parallel to the stripe electrode of the metal film upper layer MAL, one side EG1 of the metal film lower layer MDL protrudes from the metal film upper layer MAL, As a contact portion that secures connection with the electrode AED, overetching is performed on the opposite side EG2 of the metal film lower layer MDL using the metal film upper layer MAL and the metal film intermediate layer ML as a mask to form a ridge in the metal film intermediate layer MML Thus, a receding part is formed.

  The upper electrode AED formed in a later step is separated by the metal film intermediate layer MML. At this time, since the metal film upper layer MAL is thicker than the film thickness of the metal film lower layer MDL, even if the etching of the metal film lower layer MDL is finished, the metal film upper layer MAL remains on the Cu of the metal film intermediate layer MML. Can do. As a result, the surface of Cu can be protected, so that the upper bus electrode which is oxidation resistant even if Cu is used, and which separates the upper electrode AED in a self-aligned manner and serves as a scanning signal wiring for supplying power Can be formed. Further, in the case of a five-layer metal film intermediate layer MML in which Cu is sandwiched between Mo, even if the Al alloy of the metal film upper layer MAL is thin, Mo suppresses oxidation of Cu, so the metal film upper layer It is not always necessary to make MAL thicker than the film thickness of the metal film lower layer MDL.

Subsequently, the interlayer film INS3 is processed to open an electron emission portion. The electron emission portion includes one lower electrode DED in the pixel and two upper bus electrodes (a metal film lower layer MDL, a metal film intermediate layer MML, and a metal film upper layer MAL laminated film and a non-illustrated film) intersecting the lower electrode DED. It is formed in a part of the intersection of the space sandwiched between the metal film lower layer MDL, the metal film intermediate layer MML, and the metal film upper layer MAL of the adjacent pixel. This etching process can be performed, for example, by dry etching using an etching gas containing CF ₄ or SF ₆ as a main component.

  Finally, the upper electrode AED is formed. A sputtering method is used for this film formation. As the upper electrode AED, aluminum may be used, or a laminated film of Ir, Pt, and Au may be used, and the film thickness may be 6 nm, for example. At this time, the upper electrode AED is one of the two upper bus electrodes (a laminated film of the metal film lower layer MDL, the metal film intermediate layer MML, and the metal film upper layer MAL) sandwiching the electron emission portion (right side of FIG. 8C). In this case, the metal film intermediate layer MML and the metal film upper layer MAL are cut by the receding portion (EG2) of the metal film lower layer MDL having a saddle structure. On the other hand (on the left side of FIG. 8C), the upper bus electrode (laminated film of the metal film lower layer MDL, the metal film intermediate layer MML, and the metal film upper layer MAL) is separated from the contact portion (EG1) of the metal film lower layer MDL. The structure is such that the film is connected without causing disconnection and power is supplied to the electron emission portion.

  FIG. 9 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. 9, a region indicated by a broken line is a display region 6. In this display region 6, n video signal electrodes 8 and m scanning signal electrodes 9 are arranged so as to intersect with each other to form 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 electrode (cathode electrode) 8 is connected to the video signal drive circuit DDR at the video signal electrode lead-out terminal 81, and the scanning signal electrode (gate electrode) 9 is connected to the scan signal drive circuit SDR at the scan signal electrode lead-out terminal 91. 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.

  Accordingly, a two-dimensional full-color image can be displayed by supplying a video signal to the video signal electrode 8 that intersects the scanning signal electrode 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.

FIGS. 1A and 1B are diagrams for explaining an embodiment of an image display device according to the present invention, FIG. 1A being a plan view seen from the front substrate side, and FIG. 1B being seen from a direction A in FIG. It is a side view. 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 taken along line CC of FIG. 2 and a schematic cross-sectional view of a front substrate corresponding to the back substrate. It is a schematic cross section corresponding to FIG. 4 of the other Example of the image display apparatus by this invention. FIG. 6A is a schematic cross-sectional view corresponding to FIG. 4, and FIG. 6B is a plan view of the main part of FIG. 6A. FIG. 3 is a schematic cross-sectional view of a back substrate along the line DD in FIG. 2. It is a figure explaining an example of the electron source which comprises the pixel of the image display apparatus of this invention. It is explanatory drawing of the equivalent circuit example of the image display apparatus to which the structure of this invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Back substrate, 2 ... Front substrate, 3 ... Support body, 4 ... Exhaust pipe, 5 ... Sealing member, 51 ... Sealing area, 6 ... Display area 7 through-holes 8 image signal electrodes 81 image signal electrode lead terminals 82 internal electrodes 83 seal electrodes 9 scanning signal electrodes 91 ... Scanning signal electrode lead terminal 92 ... Internal electrode portion, 93 ... Sealing electrode portion, 10 ... Electron source, 11, 11A ... Connection electrode, 12 ... Interval holding member , 13 ... Adhesive member, 15 ... phosphor layer, 16 ... BM film, 17 ... Metal back (anode electrode), SUB1 ... Back substrate, INS ... Insulating film (interlayer insulation) film).

Claims (21)

A plurality of first electrodes extending in a first direction and juxtaposed in a second direction intersecting the first direction, an insulating film formed to cover the first electrode, and the insulating film A plurality of second electrodes extending in the second direction and arranged in parallel in the first direction, and an electron source provided in the vicinity of the intersection of the first electrode and the second electrode. Having a back substrate;
A front substrate having a plurality of color phosphor layers that emit light by excitation of electrons extracted from the electron source of the back substrate and a third electrode and facing the back substrate with a predetermined interval;
A support body that is inserted around the display area between the back substrate and the front substrate, and holds the predetermined interval;
A sealing member that hermetically seals the end face of the support and the front substrate and the rear substrate in a sealing region;
At least one end of the first electrode has a first electrode lead terminal drawn out from the display region through a sealing region where the back substrate and the support face each other,
At least one end of the second electrode has a second electrode lead terminal that is led out from the display region through a sealing region where the back substrate and the support face each other,
At least one of the first electrode and the second electrode has an electrode thickness in the sealing region made thinner than an electrode thickness in the display region.   The image display device according to claim 1, wherein at least one of the first electrode and the second electrode has a stacked structure of electrodes in the display region.   The image display device according to claim 2, wherein the laminated structure is a laminated material of different materials.   The second electrode has an electrode thickness in the sealing region made thinner than an electrode thickness in the display region and a small hole provided in the insulating film with the electrode in the display region and the second electrode lead-out terminal. The image display device according to claim 1, wherein the image display device is connected.   4. The image display device according to claim 1, wherein the first electrode is a video signal electrode.   The image display device according to claim 1, wherein the second electrode is a scanning signal electrode.   The image display device according to claim 1, wherein the third electrode is an anode electrode.   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 upper electrode by applying the voltage between the lower electrode and the upper electrode. 8. 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 apparatus according to claim 1, 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 1, wherein the electron source includes at least carbon nanotubes. A plurality of first electrodes extending in a first direction and juxtaposed in a second direction intersecting the first direction, an insulating film formed to cover the first electrode, and the insulating film A plurality of second electrodes extending in the second direction and arranged in parallel in the first direction, and an electron source provided in the vicinity of the intersection of the first electrode and the second electrode. Having a back substrate;
A front substrate having a plurality of color phosphor layers that emit light by excitation of electrons extracted from the electron source of the back substrate and a third electrode and facing the back substrate with a predetermined interval;
A support body that is inserted around the display area between the back substrate and the front substrate, and holds the predetermined interval;
A plurality of spacing members disposed in the display area between the front substrate and the back substrate;
An adhesive member for bonding 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 support and the front substrate and the rear substrate in a sealing region,
At least one end of the first electrode has a first electrode lead terminal drawn out from the display region through a sealing region where the back substrate and the support face each other,
At least one end of the second electrode has a second electrode lead terminal that is led out from the display region through a sealing region where the back substrate and the support face each other,
At least one of the first electrode and the second electrode has an electrode thickness in the sealing region made thinner than an electrode thickness in the display region.   The image display device according to claim 11, wherein the spacing member overlaps with the second electrode and extends in the same direction as the second electrode.   The image display device according to claim 11, wherein at least one of the first electrode and the second electrode has a stacked structure of electrodes in the display region.   The image display device according to claim 13, wherein the laminated structure is a laminated material of different materials.   The second electrode has an electrode thickness in the sealing region made thinner than an electrode thickness in the display region and a small hole provided in the insulating film with the electrode in the display region and the second electrode lead-out terminal. The image display device according to claim 11, wherein the image display device is connected.   The image display device according to claim 11, wherein the first electrode is a video signal electrode.   The image display device according to claim 11, wherein the second electrode is a scanning signal electrode.   The image display device according to claim 11, wherein the third electrode is an anode electrode.   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 upper electrode by applying the voltage between the lower electrode and the upper electrode. 19. The image display device according to claim 11, wherein the image display device is a thin-film electron source array that emits electrons.   The image display device according to claim 11, wherein the electron source is an electron-emitting device provided with a conductive film having an electron-emitting portion. 21. The image display device according to claim 11, wherein the electron source is composed of at least a carbon nanotube.

Images