JP2007212550A - Defect correcting device and defect correcting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent that a correction material adheres to a part except a defective point to form an another defect. <P>SOLUTION: A defect correcting device applying the correction material to the defective point of a panel substrate to correct the defective point is provided with an application head for applying the correction material to the defective point and a shielding mechanism inserting a shielding member between the application head and the panel substrate so that the shielding member can be retreated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a defect correcting apparatus and a defect correcting method for a display device such as a plasma display panel (PDP) and a liquid crystal display (LCD), and in particular, to correct a defect by repairing the correcting material by attaching the correcting material to a desired defect location. The present invention relates to an apparatus and a defect correction method.

  In recent display devices, the number of pixels tends to increase due to an increase in size and definition. Along with this, the probability of occurrence of defects increases. Therefore, it is necessary to repair the defect in order to improve the yield in the manufacturing process of the display device. Defects include electrode disconnection, local film thickness deficiency, and the like, which are corrected by applying a correction material.

A typical defect correction involves correcting a defect portion by applying a correction material, and the procedure is as follows. First, the XY table is moved, and a defective portion (an area including a defective portion) of the substrate placed on the table is displayed on the monitor. Next, a defect location where the correction material is applied is indicated with a cursor, and an application operation is commanded. In the application operation, after the paste-like correction material contained in the container is attached to the tip of the needle-like member, the needle-like member is moved in the horizontal direction above the defective portion, and the correction material at the tip of the needle-like member is defective. It is performed by applying to a place (for example, refer to Patent Document 1).
Japanese Patent Laid-Open No. 08-292442

  However, in such a conventional method, the needle-shaped member horizontally moves to above the defective portion after the correction material is attached to the tip. Therefore, before the defect is corrected, the correction material falls to a portion other than the defective portion. As a result, there was a problem of creating a new defect.

  The present invention has been made in consideration of such circumstances, and when correcting a defect in a display device, the defect correcting apparatus and the defect correction are designed to prevent the correction material from adhering to a part other than the defective part. A method is provided.

  The present invention provides a correction device for applying a correction material to a defective portion of a panel substrate to correct the defect, and a shielding member can be retracted between the application head for applying the correction material to the defective portion and the application head and the panel substrate. The present invention provides a defect correcting device including a shielding mechanism to be inserted into the device.

The coating head may be provided with a needle-like member, and the correction material attached to the needle-like member may be corrected by contacting the defective portion.
The shielding mechanism preferably inserts a shielding member between the coating head and the panel substrate before applying the correction material, and retracts the shielding member when applying the correction material.

  The apparatus further includes a mounting unit for mounting the panel substrate, a transport unit that relatively moves the mounting table and the coating head, and a control unit that controls the transport unit and the shielding mechanism. The conveyance unit is controlled so that the correction material is applied to the location, and the shielding member is inserted between the coating head and the panel substrate before the correction material is applied, and the shielding member is retracted when the correction material is applied. The shielding mechanism may be controlled.

  From another point of view, the present invention uses the defect correcting device, inserts a shielding member between the coating head and the panel substrate before applying the correction material, and retracts the shielding member when applying the correction material. A defect correcting method characterized by the above is provided.

In the above invention, the panel substrate is a panel substrate mainly constituting a PDP or an LCD, and the defective portion is a defective portion such as various electrodes and partition walls (ribs) formed in the panel substrate shape.
The correction material is a paste-like material containing a material corresponding to an object to be corrected. For example, if the correction object is an electrode having conductivity, the correction material is formed from a conductive material powder, a binder, a solvent, and the like. .

  According to the apparatus and method of the present invention, the shielding member can be disposed between the coating head and the panel substrate, and the shielding member can be retracted when applying the correction material. It is possible to prevent falling and correct the defect appropriately.

Hereinafter, as the best mode for carrying out the present invention, a mode in which the present invention is applied to defect correction of an address electrode of a plasma display panel (PDP) panel substrate will be described.
A plasma display panel (PDP) to which the present invention is applied is one in which a discharge is locally generated between two opposing substrates to excite and emit a phosphor layer formed on the substrate. . This is composed of a pair of substrate assemblies 50 and 50a as shown in FIG. 1 (for one pixel), for example.

  In the substrate assembly 50a, the sustain electrodes X and Y for generating surface discharge along the substrate surface are arranged on the inner surface of the front glass substrate 11 as a pair of electrodes 12 for each line. The sustain electrodes X and Y are each composed of a wide band-shaped transparent electrode 41 made of an ITO thin film and a narrow band-shaped bus electrode 42 made of a metal thin film.

  The bus electrode 42 is an auxiliary electrode for ensuring proper conductivity. A dielectric layer 17 is provided so as to cover the sustain electrodes X and Y. A protective film 18 is deposited on the surface of the dielectric layer 17. Both the dielectric layer 17 and the protective film 18 are translucent.

  Next, in the substrate assembly 50, the address electrodes A are arranged on the inner surface of the glass substrate 21 on the back side in a direction orthogonal to the sustain electrodes X and Y. Between each address electrode A, one linear or grid-like rib r is provided. It is also possible to cover the address electrode A with a dielectric layer and provide the rib r on the dielectric layer.

  In a substrate assembly (hereinafter referred to as a substrate) 50, the discharge space 30 is partitioned for each subpixel (unit light emitting region) EU by these ribs r, and the gap size of the discharge space 30 is defined.

  A phosphor layer 28 of three colors R, G, and B for color display is provided so as to cover the rear side wall surface including the upper portion of the address electrode A and the side surface of the rib r.

  The rib r is made of low-melting glass and is opaque to ultraviolet rays. As a method for forming the rib r, a step of providing an etching mask by photolithography on a solid film-like low-melting glass layer and patterning by sandblasting is used.

  The sustain electrode pair 12 corresponds to one line in the matrix display, and one address electrode A corresponds to one column. Three columns correspond to one pixel (pixel) EG. That is, one pixel EG is composed of three subpixels EU of R, G, and B arranged in the line direction.

  By the opposing discharge between the address electrode A and the sustain electrode Y, the wall charge accumulation state in the dielectric layer 17 is controlled. When a sustain pulse is alternately applied to the sustain electrodes X and Y, a surface discharge (main discharge) is generated in the subpixel EU in which a predetermined amount of wall charges exist.

  The phosphor layer 28 is excited locally by ultraviolet rays generated by surface discharge and emits visible light of a predetermined color. Of this visible light, the light transmitted through the glass substrate 11 becomes display light. Since the arrangement pattern of the ribs r is a so-called stripe pattern, the portion corresponding to each column in the discharge space 30 is continuous in the column direction across all the lines. The light emission colors of the subpixels EU in each column are the same.

  In the process of manufacturing such a PDP, the address electrodes A shown in FIG. 1 are formed on the glass substrate 21 in parallel. However, when a defect (for example, disconnection) occurs in the address electrode A to be formed, it is necessary to repair the defective portion and improve the yield in manufacturing the PDP. Therefore, a correction apparatus and a correction method of the present invention for correcting the defect portion by applying a correction material will be described below.

2 and 3 are a plan view and a front view, respectively, showing the defect correcting device, and FIG. 4 is a cross-sectional view taken along line AA in FIG.
In these drawings, a substrate positioning pin (not shown) is erected on a mounting table 51 on which a glass substrate 21 is placed, and an adsorption device (not shown) for adsorbing and fixing the substrate. Is provided.

  A pair of Y-axis direction transfer devices (hereinafter referred to as Y-axis robots) 52 and 53 are provided on both sides of the mounting table 51. An X-axis direction transfer device (hereinafter referred to as X-axis robot) 54 is mounted on Y-axis robots 52 and 53 so as to be movable in the direction of arrow YY ′. An X-axis movement base 63 is mounted on the X-axis robot 54 so as to be movable in the direction of arrow XX ′. On the X-axis moving base 63, a shielding plate motor 55a, an air cylinder 62, a CCD camera 59, and a laser emitting unit 60 are mounted.

  The Y-axis robots 52 and 53 transport the X-axis robot 54 by Y-axis motors 52a and 53a. In the X-axis robot 54, the X-axis movement base 63 is conveyed by the X-axis motor 54a.

As shown in FIG. 3, a needle mounting portion 58 is provided on the piston rod of the air cylinder 62 mounted on the X-axis movement base 63. A needle 57 is mounted on the needle mounting portion 58 in the vertical direction, and the needle 57 is raised and lowered in the vertical direction with respect to the glass substrate 21 by the operation of the air cylinder 62.
Further, one end of the shielding plate 55 is fixed to the tip of the motor output shaft 56 of the shielding plate motor 55a in parallel to the glass substrate 21 via the shielding plate fixing portion 56a.
The other end of the shielding plate 55 is provided with a correction material container 61 that stores a correction material in advance.

  When the correction material container 61 is directly below the needle 57 as shown by the solid line in FIG. 4, when the shielding plate motor 55a is driven, the shielding plate 55 moves 45 degrees in the direction of arrow A to the retracted position indicated by the phantom line. When the shielding plate motor 55a is driven in the reverse direction, the shielding plate 55 returns to the shielding position indicated by the solid line. That is, the shielding motor 55 a can shield the glass substrate 21 from the needle 57 by inserting the shielding plate 55 so as to be retractable between the needle 57 and the glass substrate 21.

  Further, when the correction material container 61 is directly below the needle 57, the air cylinder 62 lowers the needle 57, immerses the tip of the needle 57 in the correction material, adheres and holds a predetermined amount of the correction material, and then moves the needle 57 Raise.

Then, when the shielding plate 55 is retracted to the retracted position in FIG. 4, the air cylinder 62 lowers the needle 57 again, and applies a correction material to the defective portion of the address electrode A where the disconnection occurs on the glass substrate 21 (hereinafter referred to as the following). (It is called a hit point).
The CCD camera 59 mounted on the X-axis movement base 63 is used for capturing an image of the glass substrate 21, confirming a defective portion, and inputting a hit point position.

  Further, the laser emitting unit 60 is used for drying and firing the spot completion point by laser. The intensity of the laser energy is adjusted so as to correspond to the time of drying and the time of firing.

FIG. 5 is a block diagram showing a control system of the defect correcting apparatus shown in FIGS.
In FIG. 5, the control unit 80 incorporates a microcomputer composed of a CPU, a ROM, and a RAM. The control unit 80 receives outputs from the keyboard 81, mouse 83, X-axis encoder 85, Y-axis encoder 86, and CCD camera 59. Based on this, the control unit 80 drives and controls the X-axis motor 54a, the Y-axis motors 52a and 53a, the shielding plate motor 55a, the air cylinder electromagnetic valve 84, and the laser emitting unit 60. The control unit 80 causes the LCD 82 to display various conditions input from the keyboard 81 and the mouse 83, an image of the corrected portion captured by the CCD camera 59, and the like.

  The air cylinder solenoid valve 84 is interposed between an air source (not shown) and the air cylinder 62 and drives the air cylinder 62. The X-axis and Y-axis encoders 85 and 86 are coupled to the X-axis and Y-axis motors 54a and 52a, respectively, so as to detect the X and Y coordinates of the X-axis moving base 63 with respect to the glass substrate 21. It has become.

A procedure for correcting a defect of the address electrode A by this defect correcting apparatus will be described with reference to the flowchart of FIG.
First, as shown in FIGS. 2 and 3, the glass substrate 21 is placed and fixed at a predetermined position of the placing table 51 (step S1).

  The glass substrate 21 is a glass plate having an area of 1500 mm × 1000 mm and a thickness of 3.0 mm. In the effective display area of the glass substrate 21, 3000 address electrodes A having a length of 500 mm, a thickness of 1 to 3 μm, and a width of 60 to 75 μm are formed in parallel with the direction of the arrow XX ′ in FIG. . The address electrode A has a three-layer structure of Cr—Cu—Cr and is formed by a photolithography method.

  Next, the operator inputs the coordinates of the defective portion detected in advance by the inspection apparatus from the keyboard 81 to the control unit 80. As a result, the Y-axis robots 52 and 53 and the X-axis robot 54 are driven, and the CCD camera 59 moves to the input coordinates, and images a defective portion of the substrate 21. The captured image is displayed on the screen of the LCD 82 as shown in FIG. 8A, and the operator confirms the portion 87 to be corrected in the address electrode A where the disconnection has occurred (step S2).

  Next, the operator uses the mouse 83 to input the hit points P1 to P4 according to the length of the correction part as shown in FIG. 8B (step S3). The longer the length of the corrected part, the more hit points. Then, when the operator inputs “execute” from the keyboard 81 to the control unit 80 (step S4), hit points to the points P1 to P4 are executed (step S5). Next, a laser is irradiated from the laser irradiation unit 60 to the entire spots P1 to P4, and drying and baking are performed (step S6), and the defect correction work is completed (step S7).

Next, the dot work shown in step S5 of FIG. 6 will be described in more detail using the flowchart of FIG.
As shown in FIG. 7, first, it is determined whether or not the correction material container 61 is present directly below the needle 57 (step S11). If not, the shielding plate motor 55a is driven to rotate the shielding plate 55 so that the correction material container 61 exists just below the needle 57 (steps S12 and S13).
That is, the shielding plate 55 is inserted between the needle 57 and the substrate 50.

    Next, the presence / absence of a spot to be hit is determined (step S14), and when the spot is recognized as P1 shown in FIG. 8B, the Y-axis robots 52 and 53 and the X-axis robot 54 are driven. (Steps S15 and S16), the needle 57 is moved directly above the point P1 (step S17).

  Next, the air cylinder 62 is driven, the needle 57 is lowered into the correction material container 61, and the correction material is attached and held on the tip of the needle 57 (step S18). Next, the air cylinder 62 raises the needle 58 and maintains the state where the tip is pulled out from the correction material container 61.

  The state is maintained for t seconds (for example, 5 seconds) (steps S19 and S20). In the meantime, the excessively attached correction material drops from the tip of the needle 57 to the correction material container 61 by its own weight, and the correction material remaining at the tip of the needle 57 is shaped into a shape suitable for the hitting point.

  Next, the shielding plate motor 55a is driven to rotate the shielding plate 55 in the direction of arrow A in FIG. 4 and retract from the needle 57 (step S21). Next, when the air cylinder 62 is driven to lower the needle 57, the correction material at the tip of the needle 57 comes into contact with the point P1 and is hit (step S22).

  Next, the air cylinder 62 raises the needle 57 to the position shown in FIG. 3 (step S23). Next, the X-axis movement base 63 moves to a position where the laser emitting portion 60 faces the location P1, the laser emitting portion 60 emits a laser, and the correction material hit at the location P1 is dried (step S24). .

  Next, the routine returns to step S11, and steps S11 to S24 are repeated until all the points P2, P3, and P4 shown in FIG. If it is determined in step S14 that there is no remaining spot to be hit, the hitting operation in step S5 shown in FIG. 6 ends (step S25).

In this embodiment, the needle 57 is made of tungsten, the proximal end has a diameter of 0.5 mm, and has a tapered shape. The distal end has a circular flat surface with a diameter of 50 to 100 μm.
Further, the needle 57 is mounted on the needle mounting portion 58 as shown in FIG. 3, and the needle mounting portion 58 has a built-in spring mechanism that elastically supports the needle, and the contact pressure between the needle 57 and the hitting point is reduced. It is configured to be moderate.
The correction material is a paste prepared by mixing silver powder, a resin binder, and a solvent.

  In the above embodiment, the defect correction of the address electrode of the plasma display panel has been described. However, the present invention can be applied to the correction of the defect of the display device in general, for example, the dielectric layer and the phosphor of the plasma display panel. It can also be applied to pinhole defect correction, rib defect repair, liquid crystal color filter pinhole defect correction, and the like.

It is a principal part expansion perspective view of PDP which concerns on this invention. It is a top view which shows the main body of the defect correction apparatus by this invention. It is a front view which shows the main body of the defect correction apparatus by this invention. It is AA arrow sectional drawing of FIG. It is a block diagram which shows the control system of the defect correction apparatus by this invention. It is a flowchart which shows operation | movement of the defect correction apparatus by this invention. It is a flowchart which shows the detail of the principal part of the flowchart of FIG. It is explanatory drawing which shows the example of an image of the defect correction apparatus by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 21 Glass substrate 51 Mounting base 52 Y-axis robot 52a Y-axis motor 53 Y-axis robot 53a Y-axis motor 54 X-axis robot 54a X-axis motor 55 Shielding plate 55a Shielding plate motor 56 Motor output shaft 56a Shielding plate fixing | fixed part 57 needle 58 needle mounting part 59 CCD camera 60 laser emitting part 61 correction material container 62 air cylinder 63 X-axis moving base

Claims (5)

  In a correction device that applies correction material to a defective portion of a panel substrate to correct the defect, a coating head for applying the correction material to the defective portion, and a shield that removably inserts a shielding member between the coating head and the panel substrate A defect correction apparatus comprising a mechanism.   The defect correction apparatus according to claim 1, wherein the coating head includes a needle-like member, and the correction material adhered to the needle-like member is brought into contact with the defect portion to correct the defect.   2. The defect correcting device according to claim 1, wherein the shielding mechanism inserts a shielding member between the coating head and the panel substrate before applying the correction material, and retracts the shielding member when applying the correction material. A defect correction device.   The apparatus further includes a mounting unit for mounting the panel substrate, a transport unit for moving the mounting table and the coating head relative to each other, and a control unit for controlling the transport unit and the shielding mechanism. The transfer mechanism is controlled so that the coating member is applied, and a shielding member is inserted between the coating head and the panel substrate before the correction material is applied, and a shielding mechanism is retracted when the correction material is applied. The defect correction apparatus according to claim 1 to be controlled.   A defect correction apparatus using the defect correction apparatus according to claim 1, wherein a shielding member is inserted between the coating head and the panel substrate before application of the correction material, and the shielding member is retracted when the correction material is applied. Method.

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