JP2009271274A - Apparatus and method for correcting defect of color filter substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for correcting a defect of a color filter substrate, which has all functions of a quality improvement function of removing fine foreign matter, a function of subliming unremovable foreign matter and another quality improvement function of producing a part of a defective and inferior product and in which each of all functions can be changed over easily and to provide a method for correcting the defect of the color filter substrate by using this apparatus. <P>SOLUTION: The apparatus for correcting the defect of the color filter substrate, in which the color filter substrate having the surface patterned with a resist material is irradiated with laser light to correct the defect on the color filter substrate, includes: an intensity-variable laser irradiation means to be used selectively when fine foreign matter to be removed on the color filter substrate is trapped with light and the laser light having the intensity enough to correct the defect is emitted from a laser light source after the laser irradiation means is moved three-dimensionally to an optional position or when the laser light having the intensity enough to sublime/remove by laser ablation the foreign matter having strong adhesive strength to the color filter substrate is emitted from the laser light source; and a laser irradiation mechanism consisting of an optical system to be used in the laser irradiation means. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a color filter substrate defect correction device and a defect correction method for correcting defects on a substrate by irradiating a laser beam onto a color filter substrate whose surface is patterned with a resist material, which is used in a liquid crystal display device or the like. .

  In the manufacturing process of color filters for liquid crystal displays, defects in the color filter substrate are corrected in order to improve the yield. One of the typical defects in the color filter manufacturing process is a “foreign matter” defect. There are various variations of this foreign material, such as a hardened piece of resist material, a metal piece due to bearing scraping of the apparatus, or dust. In particular, a hardened piece of resist material is regarded as a problem because it frequently occurs suddenly due to slight fluctuations in manufacturing conditions.

  In the conventional correction machine, there is a correction by “polishing” that removes the foreign matter adhering to the surface by rubbing the substrate surface with a special cloth or the like for the foreign matter confirmed by the inspection device or the like. Further, as disclosed in Patent Document 1, a color filter in which a defect has occurred is irradiated with a laser beam with a threshold value of energy density set to an appropriate value, and the transparent substrate is not damaged. A method of correcting foreign matter by means such as “sublimation by laser irradiation” that removes the color filter in which the above occurs is mainly used.

  However, in the conventional correction method, for example, correction by “polishing” may damage normal product parts other than foreign matter defects. “Sublimation by laser irradiation” also removes the surrounding normal parts in order to surely remove the target foreign matter defects, and the number is small even if the dimensions are small like a hardened piece of resist material. Even for a large number of foreign matter defects, it is necessary to apply a new resist material and pattern the removed portion after removing the foreign matter. For this reason, the load of correction work became high, and it became a problem.

  On the other hand, the illumination optical system used in the manufacture of semiconductor elements and the removal of minute objects such as dust and dirt adhering to the optical element surface are major issues. Patent Document 2 applies an optical trapping technique using a laser beam. Thus, a dust collector that captures and moves a minute object in a non-contact and non-destructive manner is disclosed.

This technique is also called optical tweezers or laser manipulation. For example, as disclosed in Patent Document 3, in recent years, application to the bioscience field has been mainly studied. When light hits an object and is reflected or refracted, the traveling direction of the light changes. This phenomenon means that the momentum of light changes when light is considered as particles. The change in the momentum of light is transferred to the object, and force (radiation pressure of light) acts on the object. This force is very small, but due to the excellent coherent characteristics of the laser beam, the laser beam is rapidly narrowed down using the objective lens, and the force works toward the laser focusing position, resulting in fine particles. The particle can be moved to an arbitrary position in the three-dimensional direction by trapping and moving the laser condensing position.
Japanese Patent Laid-Open No. 05-27111 Japanese Unexamined Patent Publication No. 05-1000018 Japanese Patent Laid-Open No. 03-110510

  The present invention has been made in view of the above circumstances, and by applying the above-mentioned “optical tweezers” technology to the “foreign matter removal process” in the color filter manufacturing process, a non-defective function by removing and correcting minute foreign matters, A color filter substrate defect correction device that has both a sublimation correction function for non-removable foreign matter and a non-defective product by local creation of defective defective products, and each function can be easily switched, and a defect correction method using the same By providing, it aims at reducing the defect correction load in the manufacturing process of a color filter board | substrate.

  As a result of intensive studies for overcoming the above-mentioned problems, the present inventor has obtained the present invention. According to a first aspect of the present invention, there is provided a defect correction apparatus for a color filter substrate that corrects a defect on the substrate by irradiating a laser beam onto a color filter substrate whose surface is patterned with a resist material. Light trapping a target object on a substrate and moving it to an arbitrary position in three dimensions. The laser light source irradiates a laser beam with an intensity that corrects the defect, or the substrate has a strong adsorption force to the substrate. It is equipped with a laser irradiation mechanism comprising the same variable intensity laser irradiation means and its optical system that can select whether the laser light source irradiates the laser beam with the intensity to sublimate and remove foreign matter by laser ablation. It is a defect correction apparatus for a color filter substrate.

  Further, the invention according to claim 2 of the present invention is an object from an observation illumination light source that irradiates a defect on the substrate on substantially the same axis as the laser beam, and an object from the observation illumination light source irradiated to the substrate. It has an observation mechanism consisting of an optical element that receives and images the reflected light of the foreign matter, and the observation mechanism is connected to an image processing device that recognizes a defect / corrected portion on the substrate, and reflects the reflected light from the target foreign matter. 2. The color according to claim 1, further comprising an image processing mechanism that monitors and determines a defect existing on the substrate using image data of the surface of the substrate obtained by light reception and imaging. It is a defect correction device for a filter substrate.

  Further, the invention according to claim 3 of the present invention has a function of dropping the liquid onto the target foreign matter irradiated with the laser light and performing immersion and local cleaning, and the foreign matter or sublimation gas and the dropped liquid. The color filter substrate defect correcting device according to claim 1, further comprising a functional head having a function of sucking the color filter substrate.

  In the invention according to claim 4 of the present invention, the laser irradiation mechanism, the observation mechanism, and the functional head are arranged on the same three-axis drive shaft that moves relative to a substrate fixed on a table. Or the laser irradiation mechanism, the observation mechanism, and the functional head are arranged on the same Z-axis drive shaft that moves up and down with respect to a substrate mounted on an XY movable table. 4. The color filter substrate defect correcting device according to claim 1, further comprising a drive mechanism capable of moving the defect correction position to an arbitrary three-dimensional position.

  Next, the invention according to claim 5 of the present invention is characterized by comprising a mechanism for accurately arranging and correcting spare parts corresponding to a target foreign object or defect by optical trapping at a defective portion. Item 5. The color filter substrate defect correcting device according to any one of Items 1 to 4.

Furthermore, the invention according to claim 6 of the present invention uses the color filter substrate defect correcting device according to any one of claims 1 to 5 to provide a type of target foreign matter obtained from the observation mechanism and a correcting function. In addition, the defect correction method of the color filter substrate is characterized in that the defect on the substrate is corrected by controlling the driving mechanism, the functional head, and the laser irradiation mechanism.

  According to the defect correction apparatus for a color filter substrate of the present invention, it is possible to change the intensity of the laser light irradiated by the target foreign matter while observing and monitoring the target foreign matter near the laser light condensing position, and optical trapping. Therefore, it is possible to remove only the foreign matters that are weakly adhered to the surface. The correction result can also be judged at the same time. This makes it possible to omit steps such as re-application of resist material and patterning that occur in the case of sublimation correction.

  Further, according to the defect correction apparatus for the color filter substrate of the present invention, since the apparatus configuration can be easily switched to the sublimation correction function, the intensity of the laser beam to be irradiated is changed immediately when the removal correction is impossible. Therefore, it is not necessary to put in another sublimation correction device, and production loss can be suppressed.

  In addition, when the trapping force is not sufficient, it is possible to submerge the trapping force by buoyancy by dripping a liquid such as water onto a foreign substance. In addition, when the liquid drops, local cleaning can be realized in the correction device by using the liquid supply system function and the suction system function together.

  Furthermore, according to the defect correction apparatus for a color filter substrate of the present invention, the laser irradiation mechanism, the observation mechanism, and the functional head can be integrally moved to an arbitrary position in three dimensions with respect to the substrate. Therefore, the laser condensing position can be optimized one after another with respect to the target foreign matter, and an efficient defect correction work can be performed.

  Next, according to the defect correction apparatus for a color filter substrate of the present invention, spare parts prepared separately can be precisely placed in a part from which foreign matter has been removed or defective part by optical trapping. On the other hand, a simple and high-speed correction means can be provided, which can contribute to suppressing production loss and improving the yield rate.

  A color filter substrate defect correcting apparatus according to the present invention will be described below in detail with reference to the drawings based on an embodiment.

  First, the outline of the above-mentioned “optical tweezers” technique applied to the defect correction apparatus of the present invention will be described again. As shown in the schematic explanatory diagram of FIG. 1, the optical tweezer technique is a technique for trapping the sample 30 by condensing the laser beam 20 inside the sample 30 to be trapped by the objective lens 4 and controlling the focusing position. It is. The irradiated laser beam (photon) is under the rule of conservation of momentum even when the sample is irradiated. Since the light irradiated to the sample is refracted at the sample interface, the momentum changes. At this time, since the total amount of momentum is preserved, an external force is generated in the direction to cancel the momentum change with respect to the sample. Therefore, it is possible to capture and move (remove) the sample by preparing an optical system that can arbitrarily control the condensing position.

  FIG. 2 is a schematic view of an example of a foreign material correcting machine (removing device) as an embodiment of the color filter substrate defect correcting device of the present invention. The optical system includes a laser light source 1 capable of switching the intensity to trapping, sublimation, or thermal melting of a locally corrected material as a laser irradiation mechanism, an observation illumination light source 2 that irradiates a defect on the substrate 11 as an observation mechanism, and reflects the laser light. A dichroic mirror 3 that transmits reflected light from a sample (foreign matter / defect) 30 of light by an illumination light source, an objective lens 4, and an optical element 5 that receives reflected light from the sample (foreign matter / defect). In addition to the optical system, a functional head 7 that immerses foreign matter, performs local cleaning, and sucks foreign matter and sublimation gas, and a drying head 8 are installed. Note that an observation mechanism including an optical element is connected to the image processing apparatus 6 separately.

  The optical system and the functional head excluding the image processing device 6 are arranged on a three-axis drive shaft 9 for enabling the substrate 11 held on the table 10 to move to an arbitrary position in three dimensions. Yes. This makes it possible to monitor foreign matter at an arbitrary position, remove foreign matter by trapping, and further sublimate foreign matter when removal is impossible.

  Here, the laser light source is a light source that realizes trapping and sublimation of foreign matter. When trapping, a laser light source with variable intensity is selected in order to reduce the strength in consideration of damage to the product and to increase the strength during sublimation or material melting. In order to ensure the light intensity required for sublimation, a strong infrared band laser such as a YAG laser is preferable. The observation illumination light source is a light source for monitoring foreign matter and defects, and a general white light source can be used.

  As the dichroic mirror, an optical filter having a characteristic of reflecting light having a wavelength of red or more is selected. It is necessary to efficiently reflect the light from the laser light source and to transmit the reflected light from the sample by the observation illumination light source. The objective lens condenses light from the laser light source at a desired position. In order to obtain a high trapping force, a high-magnification lens is preferable. For example, a lens having a magnification of 100 times or more is selected.

  Reflected light from the illumination light source for observation is received by a CCD element as an optical element through a dichroic mirror and captured as an image. An image captured by the CCD element is processed by an image processing apparatus, and a defect on the substrate is monitored, and the quality of correction is determined.

  In addition, when the trapping force by the laser beam is not sufficient, the trapping force can be assisted by buoyancy by dripping a liquid such as water onto a target foreign substance from the functional head and immersing the liquid instead of immediately switching to the sublimation mode . Further, when the liquid is dropped and immersed, local cleaning is realized by the combined use of the liquid dropping system and suction system functions provided in the functional head. Further, even when the droplet does not fall, the suction system is operated to suck and remove the foreign matter separated from the product by the trapping force, or suck and discharge the sublimated foreign matter. Moreover, it is preferable to use an infrared (IR) heater etc. as a drying head which has a drying function of the location which carried out local washing.

  Moreover, in the defect correction apparatus of this invention, it is necessary to repeat the operation | movement which adjusts the focus of a laser beam to a target foreign material quickly, and moves the trapped foreign material. For this reason, the laser irradiation mechanism, the observation mechanism, and the functional head are required to have high-precision driving capability. Therefore, it is possible to move the laser irradiation mechanism, observation mechanism, and functional head only in the Z-axis direction by applying a 3-axis positioning mechanism using a servo drive or by moving the substrate table in the XY direction. However, color filter substrates used in liquid crystal display panels and the like have been increasing in size in recent years, and in order to realize the purpose of simplifying the apparatus, the laser irradiation mechanism, the observation mechanism, and the functional head have the same three axes. It is preferable to arrange on the drive shaft.

  Furthermore, in the defect correction apparatus of the present invention, the spare part corresponding to the target foreign object is created in advance and placed at a position where the focal point of the laser beam of the defect correction apparatus can move, so that the operation opposite to the foreign object removal is performed. Then, the spare parts are moved to the defective part by optical trapping, placed precisely, and further heat-dissolved with laser light as necessary to repair or correct the defective part of the color filter substrate or the laser sublimated part. It can be performed.

In addition to the mechanism described above, the defect correction apparatus of the present invention applies a flat table having functions such as loading and unloading of product substrates by pin-up, holding by vacuum suction, and desorption by purging. An industrial robot or the like is separately prepared for loading and unloading the substrate to and from the correction device.

  By providing the mechanism described above, it is possible to construct a foreign substance correcting apparatus having various foreign substance removing functions or local correcting functions. Since the defect correction apparatus for color filter substrate according to the present invention can improve the efficiency of the correction process, a contribution to productivity can be expected.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic explanatory diagram of an optical tweezer technology applied to a defect correction apparatus of the present invention. Schematic of an example of the defect correction apparatus of the color filter substrate of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Laser light source 2 ... Illumination light source 3 ... Dichroic mirror 4 ... Objective lens 5 ... Optical element 6 ... Image processing apparatus 7 ... Functional head 8 ... Drying head 9 ... 3 axis drive shaft 10 ... table 11 ... substrate 20 ... laser beam 30 ... sample (foreign matter) 40 ... reaction force against momentum change 50 ... momentum change (total) 60 ... Changes in momentum (elements)

Claims (6)

In a color filter substrate defect correcting apparatus for irradiating a laser beam onto a color filter substrate whose surface is patterned with a resist material and correcting defects on the substrate,
Light trapping is performed on a small target foreign substance on the substrate, and the laser light source is irradiated with a laser beam having an intensity for correcting a defect by moving it to an arbitrary position in three dimensions, or the substrate has a strong adsorption force to the substrate. It is equipped with a laser irradiation mechanism consisting of the same variable intensity laser irradiation means and its optical system that can select whether the laser light source irradiates the laser beam with the intensity to sublimate and remove the target foreign matter by laser ablation. A color filter substrate defect correcting device.   An observation illumination light source that irradiates a defect on the substrate on substantially the same axis as the laser light, and an optical element that receives and images reflected light of a target foreign object from the observation illumination light source irradiated on the substrate An observation mechanism, and the observation mechanism is connected to an image processing apparatus that recognizes a defect / correction portion on the substrate, and receives and captures reflected light from a target foreign object. The color filter substrate defect correcting device according to claim 1, further comprising an image processing mechanism that monitors and determines defects existing on the substrate using image data.   A function head having a function of dropping the liquid into the target foreign matter irradiated with the laser light and performing immersion and local cleaning, and a function of sucking the foreign matter or sublimation gas and the dropped liquid; 3. The defect correcting apparatus for a color filter substrate according to claim 1, wherein the defect correcting apparatus is a color filter substrate.   The laser irradiation mechanism, the observation mechanism, and the functional head are arranged on the same three-axis drive shaft that moves relative to a substrate fixed on the table, or on an XY movable table. The laser irradiation mechanism, the observation mechanism, and the functional head are arranged on the same Z-axis drive shaft that moves up and down with respect to the mounted substrate, and the defect correction position is moved to an arbitrary three-dimensional position. The color filter substrate defect correcting device according to any one of claims 1 to 3, further comprising a drive mechanism that can be used.   The collar according to any one of claims 1 to 4, further comprising a repair mechanism for precisely arranging and correcting a spare part corresponding to the target foreign object or defect at the defective portion by optical trapping. Defect correction device for filter substrate.   Using the defect correction device for a color filter substrate according to any one of claims 1 to 5, the drive mechanism, the functional head, and the type according to the type of target foreign matter obtained from the observation mechanism and the correction function, A defect correction method for a color filter substrate, wherein a defect on the substrate is corrected by controlling a laser irradiation mechanism.