JP2005197049A - Manufacturing device of image display device and manufacturing method of image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of an image display device capable of manufacturing the image display device capable of enhancing pressure resistant characteristics, display performance, and reliability and to provide a manufacturing device of the image display device. <P>SOLUTION: The manufacturing device of the image display device is equipped with a vacuum chamber 30 capable of housing a treatment target substrate 33, a treatment electrode 34 facing the treatment target substrate 33 on the inside of the vacuum chamber 30, a potential difference providing mechanism 35 applying voltage across the treatment target substrate 33 and the treatment substrate 34, and a cover 40 covering the periphery of the treatment electrode 34 and having an opening part 41 facing the treatment target substrate 33. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image display apparatus manufacturing method and an image display apparatus manufacturing apparatus, and more particularly to a manufacturing method and an apparatus capable of improving the withstand voltage characteristics of an image display apparatus.

  In recent years, as a next-generation image display device, a flat-type image display device in which a large number of electron-emitting devices are arranged to face an image display surface has been developed. There are various types of electron-emitting devices, and all of them basically use electron emission by an electric field, and image display devices using these electron-emitting devices are generally field emission displays (hereinafter referred to as field emission displays). , Referred to as FED). Among such FEDs, an image display device using a surface conduction electron-emitting device is also called a surface conduction electron-emitting display (hereinafter referred to as SED), but the term FED is used as a general term including SED. Use.

The FED generally has a front substrate and a rear substrate that are arranged to face each other with a predetermined gap. These substrates are joined to each other at their peripheral parts via a rectangular frame-shaped side wall to constitute a vacuum envelope. The inside of the vacuum envelope is maintained at a high vacuum with a degree of vacuum of about 10 ⁻⁴ Pa or less. Further, in order to support an atmospheric pressure load applied to the back substrate and the front substrate, a plurality of support members are disposed between these substrates.

  A phosphor screen including phosphor layers that emit red, blue, and green light is formed on the inner surface of the front substrate. In order to obtain practical display characteristics, an aluminum thin film called a metal back is formed on the phosphor screen. Furthermore, in order to adsorb the gas remaining inside the vacuum envelope and the gas released from each substrate, a metal film having a gas adsorption characteristic called a getter film is deposited on the metal back.

  A large number of electron-emitting devices that emit electrons for exciting the phosphor layer to emit light are provided on the inner surface of the rear substrate. A large number of scanning lines and signal lines are formed in a matrix and connected to each electron-emitting device.

  In such an FED, an anode voltage is applied to the image display surface including the phosphor screen and the metal back, and the electron beam emitted from the electron-emitting device is accelerated by the anode voltage and collides with the phosphor layer. The phosphor layer emits light. Thereby, an image is displayed on the image display surface. In this case, the anode voltage is desired to be at least several kV, preferably 10 kV or more.

  In such an FED, a gap between the front substrate and the rear substrate can be set to about 1 to 3 mm, which is significantly larger than that of a cathode ray tube (CRT) used as a display of a current television or a computer. Weight reduction and thickness reduction can be achieved.

  However, the gap between the front substrate and the rear substrate cannot be made so large from the viewpoint of resolution and electron emission efficiency characteristics, and needs to be set to about 1 to 3 mm. Therefore, in the FED, it is inevitable that a strong electric field is formed in a small gap between the front substrate and the rear substrate, and discharge (dielectric breakdown) between the two substrates becomes a problem.

  In general, the voltage at which discharge occurs varies. In addition, discharge may occur after a long period of time. Suppressing the discharge means that no discharge occurs when the anode voltage is applied, or that the probability of discharge is reduced to an acceptable level for practical use. The potential difference between the anode and the cathode that can be applied while suppressing the discharge is hereinafter referred to as a withstand voltage.

  There are various causes of discharge. One of the factors is foreign matter. That is, it is very important to remove the foreign matter that can be a trigger for the discharge before sealing the front substrate and the rear substrate in order to maintain the withstand voltage characteristic of the image display device.

As a technique for improving the withstand voltage characteristics, at least one of the front substrate and the rear substrate is a substrate to be processed, the substrate to be processed and the processing electrode are arranged to face each other in a vacuum atmosphere, and a high potential difference is given between them. Thus, a technique for removing foreign substances by electrostatic force is disclosed (Patent Document 1).
JP 2003-151435 A

  As described above, in the electric field processing step of removing foreign matter on the processing target substrate by applying a high potential difference between the processing target substrate and the processing electrode, in order to further improve the removal efficiency, or more In order to improve the breakdown voltage characteristics, it is necessary to apply a larger processing voltage between the processing target substrate and the processing electrode. In particular, when a processing substrate is subjected to electric field processing by applying a positive or negative potential to the processing electrode, the processing electrode itself collects foreign matter in the vacuum chamber, and foreign matter is applied to the processing target substrate during electric field processing. It may be reattached.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an image display device manufacturing method and an image display capable of manufacturing an image display device that has excellent withstand voltage characteristics and can improve display performance and reliability. The object is to provide a device manufacturing apparatus.

An apparatus for manufacturing an image display device according to a first aspect of the present invention provides:
An apparatus for manufacturing an image display device, comprising: a front substrate having an image display surface; and a back substrate having an electron-emitting device that emits electrons toward the image display surface,
A vacuum chamber capable of accommodating at least one of the front substrate and the rear substrate;
A processing electrode disposed opposite to the substrate to be processed in the vacuum chamber;
A potential difference applying mechanism that applies a potential difference between the substrate to be processed and the processing electrode;
A cover that covers the periphery of the processing electrode and has an opening facing the processing target substrate;
It is provided with.

An image display apparatus manufacturing method according to the second aspect of the present invention is as follows.
A method of manufacturing an image display device comprising: a front substrate having an image display surface; and a rear substrate having an electron-emitting device that emits electrons toward the image display surface,
In a vacuum chamber in which a processing electrode having a cover is arranged, the processing electrode exposed from the opening of the cover is opposed to the main surface of at least one of the front substrate and the rear substrate. Place and
In a vacuum atmosphere, while grounding the processing electrode, by applying a voltage to the processing electrode, the main surface of the substrate to be processed is processed by an electric field generated between the processing electrode,
The front substrate and the back substrate are sealed with each other in a state of facing each other in a vacuum atmosphere.

  According to the image display device manufacturing apparatus and the image display device manufacturing method configured as described above, the periphery of the processing electrode is covered by the cover, and the surface facing the processing target substrate passes through the opening of the cover. Exposed. For this reason, even if a high voltage is applied to the processing electrode during the electric field processing step, foreign matter existing in the vacuum chamber, foreign matter brought in from the outside when the substrate to be processed is carried into the vacuum chamber, Thus, it is possible to prevent foreign matter generated on the processing electrode from adhering to the processing electrode, and it is possible to keep the processing electrode clean.

  Therefore, it is possible to suppress the reattachment of the foreign matter to the substrate to be processed during the electric field processing, and it is possible to manufacture an image display device that has excellent withstand voltage characteristics and high reliability.

  In addition, by using a substrate to be processed that has undergone such an electric field treatment, a high anode voltage can be applied, and a gap between the front substrate and the rear substrate can be reduced. An image display device with improved display performance can be manufactured.

  Furthermore, the lower the anode voltage, the more the deterioration of the phosphor layer becomes a problem. According to this image display device, the anode voltage can be set higher, so the deterioration of the phosphor layer is alleviated and the product is It is possible to extend the life of the battery.

  According to the present invention, it is possible to provide an image display apparatus manufacturing apparatus and an image display apparatus manufacturing method capable of manufacturing an image display apparatus that has excellent withstand voltage characteristics and can improve display performance and reliability.

  An image display device manufacturing apparatus and an image display device manufacturing method according to an embodiment of the present invention will be described below with reference to the drawings. Here, as an image display device manufactured by this manufacturing apparatus and manufacturing method, an FED including a surface conduction electron-emitting device will be described as an example.

As shown in FIGS. 1 and 2, the FED includes a front substrate 11 and a rear substrate 12 that are opposed to each other with a gap of 1 to 2 mm. Each of the front substrate 11 and the rear substrate 12 is configured by using a rectangular glass plate having a thickness of about 1 to 3 mm as an insulating substrate. The front substrate 11 and the rear substrate 12 are flat rectangular vacuum envelopes whose peripheral portions are bonded to each other through a rectangular frame-shaped side wall 13 and whose inside is maintained at a high vacuum of about 10 ⁻⁴ Pa. 10 is constituted.

  The vacuum envelope 10 includes a plurality of spacers 14 provided therein for supporting an atmospheric pressure load applied to the front substrate 11 and the rear substrate 12. As the spacer 14, a plate shape or a column shape can be adopted.

  The front substrate 11 has an image display surface on its inner surface. That is, the image display surface includes a phosphor screen 15, a metal back 20 disposed on the phosphor screen 15, a getter film 22 disposed on the metal back 20, and the like.

  The phosphor screen 15 includes a phosphor layer 16 that emits red, green, and blue light, respectively, and a black light absorption layer 17 that is arranged in a matrix. These phosphor layers 16 may be formed in stripes or dots. The metal back 20 is formed of an aluminum film or the like and functions as an anode electrode. The getter film 22 is formed of a metal film having gas adsorption characteristics, and adsorbs the gas remaining inside the vacuum envelope 10 and the gas released from each substrate.

  The back substrate 12 includes a surface conduction electron-emitting device 18 on its inner surface. The electron-emitting device 18 functions as an electron source that excites the phosphor layer 16 of the phosphor screen 15. That is, the plurality of electron-emitting devices 18 are arranged in a plurality of columns and a plurality of rows corresponding to each pixel on the back substrate 12, and each emits an electron beam toward the phosphor layer 16. Each electron-emitting device 18 includes an electron emitting portion (not shown) and a pair of device electrodes for applying a voltage to the electron emitting portion. Further, a large number of wirings 21 for supplying a potential to the electron-emitting device 18 are provided in a matrix shape on the inner surface of the rear substrate 12, and end portions thereof are drawn out of the vacuum envelope 10.

  In such an FED, an anode voltage of, for example, 9 kV is applied to the image display surface including the phosphor screen 15 and the metal back 20 during the operation of displaying an image. Then, the electron beam emitted from the electron emitter 18 is accelerated by the anode voltage and collides with the phosphor screen 15. As a result, the phosphor layer 16 of the phosphor screen 15 is excited and emits light in a corresponding color. In this way, a color image is displayed on the image display surface.

  Next, a manufacturing apparatus for manufacturing the FED configured as described above will be described. Here, a manufacturing method and a manufacturing apparatus for performing electric field processing for improving the pressure resistance characteristics on the front substrate 11 and the rear substrate 12 used in the FED will be described. In addition, the manufacturing apparatus described here can perform the process of sealing the front substrate 11 and the back substrate 12 in a vacuum atmosphere, and does not require a separate sealing manufacturing apparatus. There is no need to evacuate the vacuum.

  As shown in FIG. 3, the manufacturing apparatus includes a vacuum chamber 30, an exhaust mechanism 32, a processing electrode 34, a potential difference applying mechanism 35, and the like. The vacuum chamber 30 is composed of a vacuum processing tank, and includes a holding mechanism 31 that holds a processing target substrate 33 therein. The processing target substrate 33 is at least one of the front substrate 11 having the image display surface on the main surface and the back substrate 12 having the electron-emitting device 18 on the main surface. The exhaust mechanism 32 evacuates the inside of the vacuum chamber 30, and includes an exhaust pump connected to the vacuum chamber 30.

  The processing electrode 34 is provided in the vacuum chamber 30. The processing electrode 34 is disposed substantially parallel to the main surface 33A of the processing target substrate 33 held by the holding mechanism 31 and facing the main surface 33A with a predetermined gap.

  The processing electrode 34 is configured by embedding a metal plate 34A in the glass 34B. For example, the processing electrode 34 has a substantially rectangular parallelepiped shape having a substantially rectangular plane facing the entire surface in the minor axis direction of the processing target substrate 33. In addition, the thickness of the glass 34B on the surface facing the processing target substrate 33 is about 0.5 mm. In order to electrically connect the processing electrode 34 and the potential difference applying mechanism 35, an insulator 42 having a through hole is disposed at a place where a part of the glass is removed and an internal metal surface is exposed, and wiring is performed through the through hole. Take out.

  The processing electrode 34 applied here is covered with a cover 40 as shown in FIGS. 3 and 4A to 4C, for example. The cover 40 is formed of a metal material and is disposed so as to cover the periphery of the processing electrode 34. The cover 40 has an opening 41. A part of the processing electrode 34 is exposed from the opening 41 of the cover 40. That is, the processing electrode 34 having a substantially rectangular parallelepiped shape has five planes surrounded by the cover 40, and the remaining one plane is exposed. The processing target substrate 33 is disposed so that its main surface 33A faces the processing electrode 34 exposed from the cover 40.

  The edge 43 that defines the opening 41 of the cover 40 is disposed so as to be sufficiently separated from the processing electrode 34. Thereby, discharge between the edge 43 and the processing electrode 34 can be suppressed.

  The potential difference applying mechanism 35 applies a predetermined potential difference between the processing target substrate 33 and the processing electrode 34 in the vacuum chamber 30. That is, the potential difference providing mechanism 35 is configured to include a high voltage power source 36. The high voltage power source 36 is electrically connected to the wiring extracted from the processing electrode 34, and can apply a predetermined voltage to the processing electrode 34. Note that the vacuum chamber 30, the substrate to be processed 33, and the cover 40 are all at the same potential, and are all grounded here. Note that grounding is not indispensable. Even if only the cover is applied, there is an effect of mechanically shielding foreign matter. Furthermore, when the potential of the processing electrode 34 is Ve and the potential of the cover is Vc, | Vc If | <| Ve |, an electrical effect also appears. The smaller the | Vc |, the greater the effect.

Next, a manufacturing method for manufacturing the FED configured as described above will be described.
First, a front substrate 11 having an image display surface and a rear substrate 12 having an electron-emitting device 18 are prepared. Subsequently, electric field processing is performed on at least one processing target substrate 33 of the front substrate 11 and the rear substrate 12 using a manufacturing apparatus as shown in FIG.

  That is, in this electric field processing step, first, the processing target substrate 33 is carried into the vacuum chamber 30 and held by the holding mechanism 31. At this time, the substrate 33 to be processed is arranged in a state where the main surface 33A and the processing electrode 34 face each other with a gap of about several millimeters, for example, 2 mm, at a predetermined electric field processing position. When the processing target substrate 33 is the front substrate 11, the main surface having the image display surface is disposed opposite to the processing electrode 34, and when the processing target substrate 33 is the rear substrate 12, the electron-emitting device. The main surface having 18 is disposed opposite to the processing electrode 34. At this time, the processing target substrate 33 is grounded.

  Subsequently, the exhaust mechanism 32 is operated to evacuate the vacuum chamber 30 to a desired degree of vacuum. Thereby, the inside of the vacuum chamber 30 is made into a vacuum atmosphere.

  Subsequently, a high voltage, for example, a voltage of 30 kV is applied to the processing electrode 34 by the high voltage power supply 36 of the potential difference applying mechanism 35 according to a predetermined rising pattern. During this time, at least one of the processing target substrate 33 and the processing electrode 34 moves in a state where a predetermined gap is maintained between them. The moving direction at this time is the approximate major axis direction of the processing target substrate 33. Thereby, while the processing electrode 34 and the processing target substrate 33 are opposed to each other, an electric field is generated between them, and the processing target substrate 33 is subjected to the electric field processing.

  This electric field processing will be described in more detail. That is, since a potential difference is applied between the processing electrode 34 and the processing target substrate 33, the foreign matter removed by the electrostatic force is attracted from the processing target substrate 33 to the processing electrode 34. Since the foreign matter adhering to the processing electrode 34 has the same potential as the processing electrode 34, the foreign matter may adhere again from the processing electrode 34 to the processing target substrate 33. For this reason, the foreign matter may reciprocate between the processing target substrate 33 and the processing electrode 34.

  Since the reciprocating foreign matter does not keep the exact same path and gradually moves to the periphery of the processing electrode 34, most of the foreign matter moves out of the surface of the processing electrode 34 after a certain period of time. . For this reason, the foreign matter is removed from the region facing the processing electrode 34.

  However, among the removed foreign substances, those moved to the peripheral member of the processing electrode 34 or the inner wall of the vacuum chamber have a potential different from that of the processing electrode 34, for example, a ground potential, and again due to a potential difference with the processing electrode 34. It may be attracted and attached to the processing electrode 34 or may be attached again to the region of the processing target substrate 33 where the electric field processing has been completed.

  On the other hand, as described above, the processing electrode 34 is covered with the cover 40 having the ground potential. For this reason, since the removed foreign substance and the cover 40 have substantially the same potential, the processing electrode 34 and the peripheral members are electrically shielded. Accordingly, it is possible to suppress foreign matters from being drawn from the periphery of the processing electrode 34 during the electric field processing. In addition, even if it is not at the ground potential as described above, even if it is mechanically covered, there is an effect of suppressing foreign matter from adhering to the processing electrode 34.

  After such an electric field treatment step, the front substrate 11 and the rear substrate 12 are sealed together in a state of being opposed to each other in a vacuum atmosphere. At this time, the front substrate 11 and the back substrate 12 are joined via the rectangular frame-shaped side wall 13 in a state where their main surfaces are opposed to each other.

  According to such an embodiment, the withstand voltage characteristics can be improved, and the anode voltage can be increased while suppressing discharge, so that a high-performance image display device can be manufactured.

  In the above-described embodiment, a space is provided between the processing electrode 34 and the cover 40. However, it is only necessary that both are electrically insulated. As shown in FIG. A structure filled with an insulator 50 such as a glass material may be used.

  Note that grounding is not indispensable. Even if a cover is provided, there is an effect. Further, when the potential of the processing electrode 34 is Ve and the potential of the cover is Vc, | Vc | <| Ve | The effect will be greater.

  Needless to say, even if this structure is applied, the same effects as those of the above-described embodiment can be obtained.

  As described above, according to this embodiment, the cover having the opening is provided on the side of the processing electrode facing the processing target substrate (that is, the front substrate or the back substrate). As a result, when applying a high electric field to the substrate to be processed and performing the electric field processing, it is possible to prevent the foreign matter in the vacuum vessel from adhering to the processing electrode, to keep the processing electrode clean, Reattachment to the substrate can be prevented.

  For this reason, the pressure | voltage resistant characteristic of a process target board | substrate can be improved. Therefore, according to the image forming apparatus manufactured using such a substrate to be processed, it is possible to improve the display performance and the reliability with excellent breakdown voltage characteristics.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the spirit of the invention in the stage of implementation. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

  For example, the processing electrode may not be a rectangular parallelepiped shape, and may be a thin plate shape or a blade shape. Further, the size of the processing electrode may be equal to or larger than that of the processing target substrate. In this case, a mechanism for moving the substrate to be processed and the processing electrode can be omitted.

FIG. 1 is a perspective view schematically showing an example of an FED manufactured by a manufacturing method and a manufacturing apparatus according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing a cross-sectional structure along the line AA of the FED shown in FIG. FIG. 3 is a diagram schematically showing an image display device manufacturing apparatus according to an embodiment of the present invention. 4A is a view schematically showing a structure of a processing electrode and a partial cross section thereof in the manufacturing apparatus shown in FIG. 4B is a diagram schematically showing a cross-sectional structure of the processing electrode in the manufacturing apparatus shown in FIG. 4C is a diagram schematically showing a structure of the processing electrode in the manufacturing apparatus shown in FIG. 3 as viewed from the processing target substrate side. FIG. 5 is a diagram schematically showing the structure of another processing electrode applicable to the manufacturing apparatus shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Vacuum envelope, 11 ... Front substrate, 12 ... Rear substrate, 30 ... Vacuum chamber, 33 ... Processing object board | substrate (front substrate, rear substrate), 34 ... Processing electrode, 35 ... Potential difference provision mechanism, 40 ... Cover, 41 ... opening

Claims (4)

An apparatus for manufacturing an image display device, comprising: a front substrate having an image display surface; and a back substrate having an electron-emitting device that emits electrons toward the image display surface,
A vacuum chamber capable of accommodating at least one of the front substrate and the rear substrate;
A processing electrode disposed opposite to the substrate to be processed in the vacuum chamber;
A potential difference applying mechanism that applies a potential difference between the substrate to be processed and the processing electrode;
A cover that covers the periphery of the processing electrode and has an opening facing the processing target substrate;
An apparatus for manufacturing an image display device, comprising:   The apparatus for manufacturing an image display device according to claim 1, wherein the cover is grounded together with the vacuum chamber. A method of manufacturing an image display device comprising: a front substrate having an image display surface; and a rear substrate having an electron-emitting device that emits electrons toward the image display surface,
In a vacuum chamber in which a processing electrode whose periphery is covered by a cover is disposed, the processing electrode exposed from the opening of the cover, and the main surface of at least one of the front substrate and the rear substrate And facing each other,
In a vacuum atmosphere, while grounding the processing electrode, by applying a voltage to the processing electrode, the main surface of the substrate to be processed is processed by an electric field generated between the processing electrode,
A method of manufacturing an image display device, wherein the front substrate and the back substrate are sealed together in a state of being opposed to each other in a vacuum atmosphere.   The method for manufacturing an image display device according to claim 3, wherein the cover is grounded together with the vacuum chamber.

Images