JP2008137118A - Defect correcting device and defect correcting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a defect correcting device which can remove a defective projection without leaving grinding streaks. <P>SOLUTION: The defect correcting device is formed of: an observation unit 4 for taking an image of a defective projection occurring on a surface of a glass substrate 1; a location detecting sensor 5 for detecting the height of the defective projection; a grinding unit 6 for removing the defective projection by a grinding tape; and a finish machining unit 7 for removing the grinding streaks occurring by the grinding tape, with a polishing pad. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a defect correction apparatus and a defect correction method, and more particularly to a defect correction apparatus and a defect correction method for correcting a protrusion defect on a substrate surface.

In recent years, flat panel displays such as liquid crystal displays and plasma displays have been developed at a rapid pace. In the manufacturing process of a flat panel display, a projection defect may occur on the surface of the glass substrate due to adhesion of foreign matter or the like. As a method of correcting the protrusion defect, there is a method of removing the protrusion defect by polishing with a polishing tape or a rotating grindstone (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 9-234660

  However, the conventional defect correction method has a problem that polishing lines remain on the surface of the glass substrate. In order to further improve the quality of the display image on the display, it is necessary to remove such polishing streaks.

  Therefore, a main object of the present invention is to provide a defect correcting apparatus and a defect correcting method capable of removing a protrusion defect without leaving a polishing streak.

  The defect correcting apparatus according to the present invention is a defect correcting apparatus for correcting a protrusion defect on a substrate surface, and a polishing unit for polishing and removing the protrusion defect, and a polishing pad generated on the substrate surface is polished and removed by a polishing pad. And a finishing processing unit.

  Preferably, the finishing unit includes driving means for rotating the polishing pad in contact with the substrate surface.

  Preferably, the finishing unit includes a driving unit that makes the polishing pad contact with the substrate surface and reciprocates.

  Preferably, the finishing unit includes a holding member that rotatably holds the polishing pad with a straight line parallel to the substrate surface as a rotation axis, and the driving unit contacts the polishing pad with the substrate surface via the holding member. .

  Preferably, the finishing unit includes an elastic member that presses the polishing pad against the surface of the substrate, and the driving unit causes the polishing pad to contact the substrate surface via the elastic member.

  Also preferably, the finishing unit uses a cerium oxide material as an abrasive.

  In the defect correcting apparatus and the defect correcting method according to the present invention, the protrusion defects are polished and removed, and the polishing streaks generated on the substrate surface are removed by polishing with a polishing pad, so that the protrusion defects are removed without leaving the polishing streaks. can do.

  FIG. 1 is a perspective view showing the overall configuration of a defect correction apparatus according to an embodiment of the present invention. In FIG. 1, this defect correction apparatus includes an XY table 2 that horizontally supports a glass substrate 1 to be corrected and moves it in the XY axis direction (horizontal direction), and an image of protrusion defects generated on the surface of the glass substrate 1. An observation unit 4 that picks up an image and displays it on the monitor 3, a position detection sensor 5 that detects the height of the protrusion defect, a polishing unit 6 that polishes and removes the protrusion defect, and polishing that occurs on the surface of the glass substrate 1. A finishing unit 7 that polishes and removes streaks, a chip discharge unit 8 that discharges chips generated during polishing, an observation unit 4, a position detection sensor 5, a polishing unit 6, and a finishing unit 7 are connected to the Z axis. A Z table 9 that moves in the direction (vertical direction) and a controller 10 that controls the entire defect correction apparatus are provided. By controlling the XY table 2 and the Z table 9, any one of the observation unit 4, the position detection sensor 5, the polishing unit 6, and the finishing unit 7 is set to a predetermined height above an arbitrary position on the surface of the glass substrate 1. It is possible to move to this position.

  FIG. 2 is a cross-sectional view showing the configuration of the polishing unit 6. In FIG. 2, the polishing unit 6 includes a polishing tape 11 for polishing the protrusion defect 1 a on the surface of the glass substrate 1, a tape supply reel 12 around which a new polishing tape 11 is wound, and a used polishing tape 11. And a tape take-up reel 13 for winding the tape. A predetermined torque is applied to the tape supply reel 12 by a torque applying mechanism (not shown), and the slack of the polishing tape 11 is prevented. The tape take-up reel 13 is driven to rotate by a motor (not shown), and takes up the polishing tape 11 at a predetermined speed. The polishing tape 11 is stretched in a U shape by rollers 14 and 15 provided below the reels 12 and 13.

  The polishing unit 6 is provided vertically between the rollers 14 and 15, and the polishing head 16 whose tip is in contact with the back surface of the polishing tape 11 is supported in a non-contact manner so that the polishing head 16 can move up and down. The hydrostatic air bearing (radial bearing) 17 to be operated, the head pressing mechanism 18 for adjusting the pressing force (pressure) against the projection defect portion of the polishing head 16 to a predetermined value, and the vertical displacement of the polishing head 16 are detected without contact. A differential transformer type displacement meter 19 and a vertical movement table 20 are provided. The vertical movement table 20 includes a rail portion 20a and a slide portion 20b provided vertically. The polishing tape 11, the reels 12 and 13, the rollers 14 and 15, the polishing head 16, the static pressure air bearing 17, the head pressing mechanism 18, and the differential transformer displacement meter 19 are mounted on the slide portion 20b. The position of the slide part 20b is moved in the vertical direction along the rail part 20a by a drive part (not shown).

  Next, the operation of this tape polishing apparatus will be described. First, the position detection sensor 5 detects the height of the normal part of the surface of the glass substrate 1 and the height of the protrusion defect 1a. Next, the tip of the polishing head 16 is positioned at a predetermined position above the projection defect 1 a by the XY table 2 and the Z table 9. Next, the polishing table 11 is driven while controlling the vertical movement table 20 to lower the slide portion 20b at a predetermined speed, and polishing is performed at a predetermined cutting speed to the height of the normal portion on the surface of the glass substrate 1. During polishing, the cutting speed is controlled based on the detection result of the displacement meter 19 so that the amount of displacement of the polishing head 16 relative to the slide portion 20b is constant. If the protrusion defect 1a is long and cannot be removed once, the entire protrusion defect 1a is removed by changing the polishing position and repeating the polishing a required number of times.

  FIG. 3 is a diagram showing the configuration of the finishing unit 7. In FIG. 3, the finishing unit 7 polishes the water droplet supply unit 21 that supplies water droplets to the region to be polished on the surface of the glass substrate 1 and the polishing streaks generated on the surface of the glass substrate 1 when the projection defect 1a is polished. A cylindrical polishing pad 22 for removal, a rotating shaft 23, a holding member 24 that supports the upper end surface of the polishing pad 22 on the lower end portion of the rotating shaft 23 so as to be able to swing, and a motor that drives the polishing pad 22 to rotate. 25, an elastic member 26 provided between the lower end surface of the rotation shaft 25a of the motor 25 and the upper end surface of the rotation shaft 23, and a vertical movement table 27 for moving the motor 25 in the vertical direction. The vertical movement table 27 includes a rail portion 27a and a slide portion 27b provided vertically. The motor 25 is fixed to the slide part 27 b, and the slide part 27 b is fixed to the Z table 9. The position of the slide part 27b is moved in the vertical direction along the rail part 27a by a drive part (not shown). A cerium oxide powder, which is an abrasive, is applied to the lower end surface of the polishing pad 22.

  As shown in FIGS. 4A and 4B, the holding member 24 includes a disk member 24a and a rotating shaft 24b. The upper end surface of the polishing pad 22 is fixed to the lower end surface of the disc member 24a. For example, by inserting a plurality of protrusions provided on the lower end surface of the disc member 24a into a plurality of recesses provided on the upper end surface of the polishing pad 22, the polishing pad 22 can be easily attached and detached.

  The rotating shaft 24b is erected at the center of the upper end surface of the disk member 24a. For example, the lower end portion of the rotary shaft 23 processed into a plate shape is inserted into a groove formed on the upper end surface of the rotary shaft 24b, and the lower end portion of the rotary shaft 23 and the upper end portion of the rotary shaft 24b are horizontally penetrated. By forming a hole and inserting a pin into the hole, the holding member 24 can be rotatably supported around the pin. Thereby, even when the parallelism between the surface of the glass substrate 1 and the lower end surface of the polishing pad 22 is poor due to a mounting error of the machine, the lower end surface of the polishing pad 22 can be brought into contact with the surface of the glass substrate 1 without a gap. it can.

  As shown in FIGS. 5A and 5B, the elastic member 26 includes a spring material that expands and contracts in the vertical direction. Thereby, it becomes possible to always press the polishing pad 22 against the surface of the glass substrate 1 with a predetermined force. The elastic force of the spring material can be selected so that the polishing streaks after the polishing process can be removed, but the surface of the glass substrate 1 is not greatly shaved. Instead of using a spring material, the elastic member 26 may be formed of a material that can be elastically deformed, such as rubber.

  Next, the usage method of this defect correction apparatus is demonstrated. First, the height of the projection defect 1a and the height of the surface of the glass substrate 1 are measured using the position detection sensor 5, and the projection defect 1a is polished and removed using the polishing unit 6 based on the measurement result. At this time, it is assumed that polishing streaks due to the polishing tape 11 are generated on the surface of the glass substrate 1.

  Next, the tables 2, 9, and 27 are driven to move the lower end surface of the polishing pad 22 at a high speed above the region where the polishing streaks are generated. Next, the motor 25 is driven to rotate the polishing pad 22. The rotation speed of the polishing pad 22 is set to about 100 to 5000 rotations per minute, for example. Next, water is dropped by the water droplet supply unit 21 onto the region to be polished on the surface of the glass substrate 1. Next, the vertical movement table 27 is driven to lower the polishing pad 22 at a low speed until the lower end surface of the polishing pad 22 comes into contact with the surface of the glass substrate 1, and the polishing pad 22 is pressed against the surface of the glass substrate 1 to finish processing. To do.

  At this time, since cerium oxide is used as the polishing agent, both chemical polishing by chemical change (ion exchange) between cerium oxide and glass and mechanical polishing by friction between the polishing pad 22 and the glass substrate 1 are performed. And a good finishing process is performed.

  In this embodiment, the projection defects 1a generated on the surface of the glass substrate 1 are removed by polishing with the polishing tape 11, and the polishing streaks generated by the polishing tape 11 are removed by polishing with the polishing pad 22. Therefore, high quality correction can be performed without adversely affecting the shape and size of the surface of the glass substrate 1.

  In this embodiment, the case where the projection defect 1a of the glass substrate 1 is polished has been described. However, the object to be polished is not limited to the glass substrate 1, and needless to say, the substrate may be of any material. Yes. Further, depending on the material of the substrate, it is possible to polish without dropping water. Moreover, you may grind | polish the protrusion defect 1a not only by tape grinding | polishing but by other methods, such as a rotating grindstone.

  FIG. 6 is a diagram showing a modified example of this embodiment, and is a diagram to be compared with FIG. Referring to FIG. 6, this finishing unit 30 is different from finishing unit 7 in FIG. 3 in that motor 25 is replaced with a reciprocating mechanism 31. The reciprocating mechanism 31 includes an arm portion 31a and a slide portion 31b. The arm portion 31 a is provided horizontally, and its base end portion is fixed to the slide portion 27 b of the vertical movement table 27. The slide part 31b is provided so as to be able to reciprocate in the horizontal direction along the arm part 31a, and is reciprocated by a drive part (not shown). The lower end portion of the slide portion 31 b is coupled to the upper end portion of the rotating shaft 23 via the elastic member 26. The slide part 27b of the vertical movement table 27 is lowered to press the lower end surface of the polishing pad 22 against the surface of the glass substrate 1, and the slide part 31b of the reciprocating mechanism 31 is reciprocated to thereby polish the polishing streaks on the surface of the glass substrate 1. Can be removed by polishing.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 is a perspective view showing an overall configuration of a defect correction apparatus according to an embodiment of the present invention. It is sectional drawing which shows the structure of the grinding | polishing processing unit shown in FIG. It is a figure which shows the structure of the finishing process unit shown in FIG. It is a figure which shows the swing operation | movement of the holding member shown in FIG. It is a figure which shows the expansion-contraction operation | movement of the elastic member shown in FIG. It is a figure which shows the example of a change of this embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Glass substrate, 1a Protrusion defect, 2 XY table, 3 Monitor, 4 Observation unit, 5 Position detection sensor, 6 Polishing processing unit, 7, 30 Finishing processing unit, 8 Chip discharge unit, 9 Z table, 10 Controller, 11 Polishing tape, 12 Tape supply reel, 13 Tape take-up reel, 14, 15 Roller, 16 Polishing head, 17 Hydrostatic air bearing, 18 Head pressing mechanism, 19 Differential transformer displacement meter, 20, 27 Vertical movement table, 20a, 27a Rail part, 20b, 27b Slide part, 21 Water drop supply part, 22 Polishing pad, 23 Rotating shaft, 24 Holding member, 24a Disk member, 24b Rotating shaft, 25 Motor, 25a Rotating shaft, 26 Elastic member, 31 Reciprocating mechanism, 31a arm part, 31b slide part.

Claims (7)

In a defect correction device that corrects protrusion defects on the substrate surface,
A polishing unit for polishing and removing the protrusion defects;
A defect correcting apparatus, comprising: a finishing unit that polishes and removes polishing streaks generated on the substrate surface with a polishing pad.   The defect correction apparatus according to claim 1, wherein the finishing unit includes a driving unit that drives the polishing pad to rotate while contacting the surface of the substrate.   The defect correction apparatus according to claim 1, wherein the finishing unit includes a driving unit that reciprocates the polishing pad in contact with the substrate surface. The finishing unit includes a holding member that rotatably holds the polishing pad with a straight line parallel to the substrate surface as a rotation axis.
The defect correction apparatus according to claim 2, wherein the driving unit makes the polishing pad contact the surface of the substrate through the holding member. The finishing unit includes an elastic member that presses the polishing pad against the substrate surface,
5. The defect correction apparatus according to claim 2, wherein the driving unit makes the polishing pad contact the surface of the substrate via the elastic member. 6.   The defect finishing apparatus according to claim 2, wherein the finishing unit uses a cerium oxide material as an abrasive. In a defect correction method for correcting protrusion defects on a substrate surface,
A defect correction method comprising polishing and removing the protrusion defects, and polishing and removing polishing streaks generated on the substrate surface with a polishing pad.

Images