JP2008296149A - Coating mechanism and apparatus for correcting defect by using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating mechanism capable of applying a liquid material thinly, uniformly and quickly and an apparatus for correcting a defect by using the coating mechanism. <P>SOLUTION: The apparatus for correcting the defect by using the coating mechanism is characterized in that a tapered part 2 is formed at the tip of a coating needle 1, a flat plane 3 is formed at the tip of the tapered part, a correction fluid 4 is applied to the tip of the coating needle 1, the correction fluid-applied tip of the coating needle 1 is brought into contact with a substrate 5 and the coating needle 1 of such a contacted state is moved in parallel to the substrate 5 to apply the correction fluid 4 linearly. Therefore, the correction fluid 4 can be applied thinly, uniformly and quickly. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an application mechanism and a defect correction apparatus using the same, and more particularly to an application mechanism for applying a liquid material to a substrate and a defect correction apparatus using the same.

  In recent years, the number of pixels has increased along with the increase in size and definition of LCDs (liquid crystal display devices), making it difficult to manufacture LCDs without defects and increasing the probability of occurrence of defects. Under such circumstances, in order to improve the yield, a defect correcting device for correcting defects generated in the manufacturing process of the color filter of the LCD has become indispensable for the production line.

  Recently, LCDs having a size of about 37 to 45 inches are also commercially available, and the size of one pixel has increased from about 60 μm × 200 μm to about 200 μm × 600 μm of a small panel. As the pixel size increases, the defect size increases and the correction size also increases. In such a situation, even with the correction quality that was not a problem with the conventional small correction size, it may become a problem because it becomes an area that can be seen with a large correction size.

  7A to 7C are diagrams showing defects that occur in the manufacturing process of the color filter of the LCD. 7A to 7C, the color filter includes a glass substrate, a lattice pattern called a black matrix 50 formed on the surface thereof, a plurality of sets of R (red) pixels 51, and G (green). A pixel 52 and a B (blue) pixel 53. In the manufacturing process of the color filter, the white defect 54 in which the color of the pixel or the black matrix 50 is lost as shown in FIG. 7A, or the color of the adjacent pixel is mixed as shown in FIG. 7B. Or a black defect 55 in which the black matrix 50 protrudes from the pixel, or a foreign substance defect 56 in which a foreign substance adheres to the pixel as shown in FIG.

  As a method for correcting the white defect 54, ink having the same color as that of the pixel in which the white defect 54 is present is attached to the tip of the application needle, the ink layer on the circular flat surface at the tip of the needle is transferred to the white defect 54, and the circular defect There is a method of covering the white defect 54 with an ink layer (see, for example, Patent Document 1).

  Further, as a method of correcting the black defect 55 and the foreign matter defect 56, the defective portion is laser-cut to form a rectangular white defect 54, and the rectangular white defect 54 is formed using a coating needle having a rectangular tip flat surface. There is a method of transferring a rectangular ink layer (see, for example, Patent Document 2).

  There is also a method in which additional processing is performed on the tip of the application needle and the amount of ink applied is adjusted by the time during which the substrate and the application needle are in contact (see Patent Document 3).

  FIG. 8A is a front view showing the tip of such an application needle 61, FIG. 8B is a bottom view thereof, and FIG. 8C is a VIIIC-VIIIC of FIG. 8A. FIG. 4D is a cross-sectional view taken along line VIIID-VIIID in FIG. 4A, and FIG. 5E is a cross-sectional view taken along line VIIIE-VIIIE in FIG.

  8A to 8E, the application needle 61 is obtained by cutting a cylindrical tip portion obliquely at intervals of 90 degrees. As a result, four flat surfaces 62 formed obliquely with respect to the central axis are formed at the tip of the application needle 61, and a square flat surface 63 is formed at the tip. The application needle 61 is made of metal.

  FIG. 9A is a cross-sectional view showing a state in which the ink 64 is attached to the tip portion of the application needle 61 shown in FIGS. 8A to 8E, and FIG. IXB-IXB sectional view taken along the line IXC-IXC taken along the line IXC-IXC, and FIG. 4D taken along the line IXD-IXD of FIG. is there.

  When the tip end of the application needle 61 is immersed in the ink 64 and pulled up, an ink pool is generated on the flat surface 62 due to surface tension, and the flat surface 63 and its vicinity are covered with a thin ink layer. The flat surface 62 holds more ink 64 than the outer peripheral surface other than the flat surface 62 due to the surface tension of the ink 64. When the flat surface 63 at the tip of the application needle 61 is brought into contact with the substrate surface, the ink 64 adheres to the substrate surface, causing an imbalance in surface tension, so that the ink 64 accumulated on the flat surface 62 is supplied to the tip, and the substrate To be applied.

  FIGS. 10A to 10C are diagrams showing a method of applying the ink 64 to the white defect 54 using the application needle 61 shown in FIGS. 9A to 9D, and particularly FIG. ) Is a cross-sectional view taken along line XB-XB in FIG. In the manufacturing process of the color filter, a foreign substance defect occurs in the G pixel 52, and the entire G pixel 52 is laser-cut to convert the G pixel 52 into a white defect 54 as shown in FIG. . In the white defect 54, the glass substrate 65 of the color filter is exposed.

  In this coating method, the tip of the coating needle 61 is brought into contact with one end of the white defect 54, and in this state, the coating needle 61 is wide in the width direction of the white defect 54 and in a direction horizontal to the surface of the substrate 65. It is moved relative to the substrate 65 and applied to the entire white defect. When the tip of the application needle 61 is brought into contact with the surface of the substrate 65, the ink 64 is supplied from the ink reservoir to the contact portion between the application needle 61 and the substrate 65. Thereby, the ink 64 can be uniformly applied to the white defect 54 in a short time.

As shown in FIGS. 11A to 11C, when the application needle 61 is stopped and applied at the center of the white defect 54, before the ink 64 spreads over the entire area of the white defect 54, adjacent pixels are used. 51 and 53. Further, as shown in FIGS. 12A to 12C, when the white defect 54 is applied in a plurality of times (three times in the figure) in the longitudinal direction, irregularities are formed on the surface of the ink 64, resulting in uneven color. Will occur.
Japanese Patent Laid-Open No. 9-61296 JP-A-9-262520 JP 2007-94341 A

  As described above, defects generated in the colored layer of the color filter are corrected by using a coating needle. Recently, an overcoat layer, an ITO transparent electrode layer, and an alignment film formed on the colored layer of the color filter are used. Defect correction is also being performed on the layer and the alignment film layer formed on the TFT electrode layer.

  However, since the film thickness of the alignment film layer (0.1 μm or less) is much thinner than the film thickness of the colored layer of the color filter (about 2 μm), the alignment film layer is corrected by the method shown in FIGS. There is a problem that the thickness of the correction layer becomes too large.

  Further, when correcting a defect in the alignment film on the TFT electrode layer, there is a problem in that a discharge due to static electricity is generated between the TFT electrode layer and the tip of the coating needle 61 and the TFT electrode layer is damaged.

  Therefore, a main object of the present invention is to provide an application mechanism that can apply a liquid material thinly and uniformly and a defect correcting apparatus using the same.

  In the coating mechanism according to the present invention, a flat surface is formed at the tip of the coating mechanism for coating a liquid material on a substrate, and a tapered portion whose cross section gradually increases along the axial direction from the tip is formed at the tip. And a driving means for applying the liquid material by causing the liquid material to adhere to the tip of the application needle, bringing the tip of the application needle into contact with the substrate, and moving the application needle parallel to the substrate. It is characterized by.

Preferably, at least the surface of the tip of the application needle is formed of an insulating material.
Preferably, the insulating material is ceramic.

  In addition, a defect correcting apparatus according to the present invention includes the coating mechanism, and the coating mechanism corrects the defective portion by applying a liquid material to the defective portion on the substrate.

  Preferably, the substrate is a TFT electrode substrate for a liquid crystal display device, and the defective portion is a portion where the alignment film layer which is the uppermost layer of the TFT electrode substrate is not normally formed.

  Preferably, the substrate is a color filter substrate for a liquid crystal display device, and the defective portion is a portion where the alignment film layer which is the uppermost layer of the color filter substrate is not normally formed.

  In the coating mechanism and the defect correcting device according to the present invention, a liquid material is attached to the coating needle having a tapered portion formed at the tip portion, the cross-section of which gradually increases in the axial direction from the tip, and the tip portion of the coating needle. Driving means for applying the liquid material by bringing the tip of the application needle into contact with the substrate and moving the application needle in parallel with the substrate. Therefore, the liquid material can be applied thinly and rapidly.

  In addition, by forming the surface of at least the tip of the application needle with an insulating material, it is possible to prevent the surface of the substrate from being damaged by electrostatic discharge.

  Fig.1 (a) is a front view which shows the front-end | tip part of the application needle | hook 1 used with the defect correction apparatus by one Embodiment of this invention, The same figure (b) is the bottom view, The same figure (c) FIG. 4A is a cross-sectional view taken along the line IC-IC in FIG. 1A, FIG. 4D is a cross-sectional view taken along the line ID-ID in FIG. 1A, and FIG. FIG.

  In FIGS. 1A to 1E, a tip portion of the application needle 1 is provided with a tapered portion 2 in which the cross-sectional area of the application needle 1 gradually increases from the distal end of the application needle 1 toward the proximal end. A flat surface 3 is provided at the tip of the needle 1.

  Further, at least the surface of the tip of the application needle 1 is made of ceramic having excellent low chargeability, insulation and chemical resistance. The entire application needle 1 may be formed of ceramic, or only the surface of the tip of the application needle 1 may be formed of ceramic, and the other part may be formed of metal. Further, a material other than ceramic may be used as long as it is an insulating material excellent in low chargeability, insulation, and chemical resistance.

  2A is a cross-sectional view showing a state in which the correction liquid 4 is attached to the tip of the application needle 1 shown in FIGS. 1A to 1E, and FIG. ) Is a cross-sectional view taken along the line IIB-IIB of FIG. 5C, FIG. 2C is a cross-sectional view taken along the line IIC-IIC of FIG. 1A, and FIG. It is.

  When the tip of the application needle 1 is immersed in the correction liquid 4 and pulled up, a correction liquid pool is generated at the upper portion of the taper portion 2 due to surface tension, and the flat surface 3 and the vicinity thereof are covered with a thin correction liquid layer. When the flat surface 3 at the tip of the application needle 1 is brought into contact with the substrate surface, the correction liquid adheres to the substrate surface, causing an imbalance in surface tension, and the correction liquid 4 accumulated on the upper portion of the taper portion 2 is supplied to the tip. And applied to the substrate.

  FIGS. 3A and 3B are cross-sectional views showing the operation of applying the correction liquid 4 to the surface of the substrate 5 using the application needle 1 shown in FIGS. 2A and 2B. 3A and 3B, the surface of the substrate 5 is moved by relatively moving the coating needle 1 and the substrate 5 in the horizontal direction with the flat surface 3 at the tip of the coating needle 1 being in contact with the surface of the substrate 5. The correction liquid 4 can be uniformly applied in a short time in a line. At this time, since the flat surface 62 as shown in FIG. 8 is not formed on the tapered portion 2 of the application needle 1, the correction liquid layer does not become too thick.

  FIG. 4A is a cross-sectional view illustrating the substrate 5 to be corrected. In FIG. 4A, a substrate 5 is a TFT electrode substrate for a liquid crystal display device, in which a TFT electrode layer 7 and an alignment film layer 8 are laminated on the surface of a glass substrate 6. It is assumed that a defective portion 8a in which a part of the alignment film layer 8 is missing occurs and the TFT electrode layer 7 is exposed from the defective portion 8a. Such a defective portion 8a occurs, for example, when the alignment film layer 8 is formed in a state in which foreign matter adheres to the surface of the TFT electrode layer 7, and then the foreign matter is detached. The TFT electrode layer 7 includes a plurality of X electrodes and a plurality of Y electrodes arranged so as to intersect with each other, and TFTs disposed at respective intersections of the X electrodes and the Y electrodes.

  Using the method shown in FIGS. 3 (a) and 3 (b), as shown in FIG. 4 (b), after applying the correction liquid 4 to the defective portion 8a, the correction liquid 4 is cured, thereby causing the defective portion 8a. Can be corrected. At this time, since at least the surface of the tip of the application needle 4 is made of ceramic, electrostatic discharge occurs between the tip of the application needle 4 and the TFT electrode layer 7 and the TFT electrode layer 7 is damaged. There is nothing. Needless to say, this correction method can also be applied to correction of a defective portion of the alignment film layer which is the uppermost layer of the color filter substrate.

  FIG. 5 is a partially omitted perspective view showing the configuration of the correction liquid application mechanism 10 that applies the correction liquid 4 using the application needle 1. In FIG. 5, the correction liquid application mechanism 10 includes an application needle 1 for applying correction liquid and an application needle drive cylinder 11 for driving the application needle 1 vertically. The application needle 1 is provided at the distal end portion of the drive shaft 12 of the application needle drive cylinder 11 via a holding member 13.

  The correction liquid application mechanism 10 includes a rotary table 14 provided horizontally, and a plurality of correction liquid tanks 17 to 20 are sequentially arranged on the rotary table 14 in the circumferential direction. A cleaning device 21 and an air purge device 22 are provided. A rotary shaft 15 is erected at the center of the rotary table 14. Further, the rotary table 14 is formed with a notch 16 for allowing the needle 1 to pass when applying the correction liquid. Different types of correction fluids 4 are appropriately injected into the correction fluid tanks 17 to 20. The cleaning device 21 is for removing the correction liquid 4 attached to the application needle 1, and the air purge device 22 is for blowing off the cleaning liquid attached to the application needle 1.

  Further, the correction fluid application mechanism 10 includes an index motor 23 for rotating the rotary shaft 15 of the rotary table 14, and further includes an index plate 24 that rotates together with the rotary shaft 15, and the rotary table 14 via the index plate 24. An index sensor 25 for detecting the rotation position of the rotary table 14 and an origin return sensor 26 for detecting that the rotation position of the rotary table 14 has returned to the origin via the index plate 24 are provided. The motor 23 is controlled based on the outputs of the sensors 25 and 26, and rotates the rotary table 14 so that any one of the notch 16, the correction liquid tanks 17 to 20, the cleaning device 21, and the air purge device 22 is below the application needle 1. To be located.

  The application needle drive cylinder 11 and the motor 23 are fixed to a Z-axis table (not shown), and the Z-axis table and the substrate 5 to be repaired are an XY table (not shown) below the application needle 1. ) Relative positioning.

  Next, the operation of the correction fluid application mechanism 10 will be described. First, the XY table and the Z-axis table are driven, and the tip of the application needle 1 is positioned at a predetermined position above the defective portion 8 a of the substrate 5. Next, the rotary table 14 is rotated by the motor 23, and a desired correction liquid tank (for example, 17) is moved below the application needle 1. Next, the application needle 1 is driven up and down by the application needle drive cylinder 11, and the correction liquid 4 is attached to the tip of the application needle 1.

  Next, the rotary table 14 is rotated by the motor 23, and the notch 16 is moved below the application needle 1. Next, the application needle 1 is driven downward by the application needle drive cylinder 11, and the flat surface 3 at the tip of the application needle 1 is brought into contact with one end portion of the defective portion 8a. In this state, the XY table is driven so that the application needle 1 is relatively moved to the other end of the defective portion 8a, and the application needle 1 is driven upward by the application needle driving cylinder 11. As a result, the correction liquid 4 attached to the tip of the application needle 1 is applied to the defective portion 8 a of the substrate 5.

  When cleaning the application needle 1, the rotary table 14 is rotated by the motor 23, and the cleaning device 21 is moved below the application needle 1. Next, the application needle 1 is driven up and down by the application needle drive cylinder 11, and the correction liquid 4 attached to the application needle 1 is washed. Next, the rotary table 14 is rotated by the motor 23, and the air purge device 22 is moved below the application needle 1. Next, the application needle 1 is driven up and down by the application needle drive cylinder 11, and the cleaning liquid adhering to the application needle 1 is blown off.

  FIG. 6 is a diagram showing an overall configuration of a defect correction apparatus equipped with the correction liquid application mechanism 10 shown in FIG. In FIG. 6, this defect correction apparatus can be roughly classified into a defect correction head unit including an observation optical system 30, a CCD camera 31, a laser 32, a correction liquid application mechanism 10, and a correction liquid curing illumination 33, and A Z-axis table 34 for moving the defect correction head portion in a direction perpendicular to the substrate 5 (Z-axis direction), an X-axis table 35 for mounting the Z-axis table 34 and moving it in the X-axis direction, and the substrate 5 From a Y-axis table 36 for moving in the Y-axis direction, a control computer 37 for controlling the operation of the entire apparatus, and an operation panel 38 for inputting instructions from the operator to the control computer 37 Composed.

  The observation optical system 30 is for observing the surface state of the substrate 5 and the state after the correction liquid 4 is applied by the correction liquid application mechanism 10. An image observed by the observation optical system 30 is converted into an electric signal by the CCD camera 31 and displayed on the monitor screen of the control computer 37. The correction liquid curing illumination 33 irradiates light for curing the correction liquid 4 applied by the correction liquid application mechanism 10. When the correction liquid 4 is an ultraviolet curing type, the ultraviolet illumination is selected as the correction liquid curing illumination 33 and mounted on the apparatus. When the correction liquid 4 is a thermosetting type, the halogen illumination is selected as the correction liquid curing illumination 33 and mounted on the apparatus. The laser 32 is used to remove foreign matter.

  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.

It is a figure which shows the structure of the front-end | tip part of the application needle | hook used with the defect correction apparatus by one Embodiment of this invention. It is a figure which shows the correction liquid adhesion state of the front-end | tip part of the application needle | hook shown in FIG. It is a figure which shows the correction liquid application | coating method using the application needle | hook shown in FIG. It is sectional drawing which illustrates the board | substrate of correction object. It is a figure which shows the structure of the correction liquid application | coating mechanism using the application needle | hook shown in FIG. It is a figure which shows the whole structure of the defect correction apparatus provided with the correction liquid application | coating mechanism shown in FIG. It is a figure which shows the defect which generate | occur | produces in a color filter. It is a figure which shows the structure of the front-end | tip part of the application needle | hook used with the conventional defect correction apparatus. It is a figure which shows the correction liquid adhesion state of the front-end | tip part of the application needle | hook shown in FIG. It is a figure which shows the correction liquid application | coating method using the application needle | hook shown in FIG. It is a figure for demonstrating the effect of the correction liquid application | coating method shown in FIG. It is another figure for demonstrating the effect of the correction liquid application | coating method shown in FIG.

Explanation of symbols

  1,61 coating needle, 2 taper portion, 3,62,63 flat surface, 4,64 correction solution, 5 substrate, 6,65 glass substrate, 7 TFT electrode layer, 8 alignment film layer, 8a defect portion, 10 correction solution Application mechanism, 11 Application needle drive cylinder, 12 Drive shaft, 13 Holding member, 14 Rotation table, 15 Rotation shaft, 16 Notch, 17-20 Correction liquid tank, 21 Cleaning device, 22 Air purge device, 23 Motor, 24 Index plate , 25 Index sensor, 26 Origin return sensor, 30 Observation optical system, 31 CCD camera, 32 Laser, 33 Correction liquid curing illumination, 34 Z-axis table, 35 X-axis table, 36 Y-axis table, 37 Control computer 38 Operation panel 50 Black matrix 51 R pixel 52 G pixel 53 B pixel 54 White defect 55 black defect, 56 defective foreign matter, 64 ink.

Claims (6)

In an application mechanism that applies a liquid material to a substrate,
An application needle in which a flat surface is formed at the tip, and a tapered portion whose cross section gradually increases along the axial direction from the tip is formed at the tip.
Drive means for applying the liquid material by adhering the liquid material to the tip of the application needle, bringing the tip of the application needle into contact with the substrate, and moving the application needle in parallel with the substrate; An application mechanism characterized by that.   The coating mechanism according to claim 1, wherein at least a tip portion of the coating needle is formed of an insulating material.   The coating mechanism according to claim 2, wherein the insulating material is ceramic. A coating mechanism according to any one of claims 1 to 3,
The defect correction apparatus, wherein the coating mechanism applies the liquid material to a defective portion on the substrate to correct the defective portion. The substrate is a TFT electrode substrate for a liquid crystal display device,
5. The defect correction apparatus according to claim 4, wherein the defect portion is a portion where an alignment film layer that is the uppermost layer of the TFT electrode substrate is not normally formed. The substrate is a color filter substrate for a liquid crystal display device,
5. The defect correction apparatus according to claim 4, wherein the defect portion is a portion where an alignment film layer that is the uppermost layer of the color filter substrate is not normally formed.

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