JP4923787B2 - Defect correction method using laser light - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a defect correction method by a laser beam in which a compound substrate disposed with a resin section of a correction object and an underlayer composed of ITO which is the underlayer thereof, successively from the surface side of a substrate on the substrate can be readily and surely subjected to correction of a projection defect of the resin section. <P>SOLUTION: The projection defect removal to remove the projection defect and to expose the underlayer of a projection defect region is performed by controlling the irradiation intensity which is the light intensity (W/area) when the laser beam is irradiated onto the compound substrate to set the irradiation intensity at which the resin section can be removed and damage is not given to the underlayer, and by repetitively subjecting the region including the projection defect to shot (pulse) irradiation. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  In the present invention, a laser beam is used to detect protrusion defects on the resin part in a composite base material in which a resin part to be corrected and a base layer made of ITO, which is the base, are arranged on the base in order from the surface side. More particularly, the present invention relates to a laser defect correcting method for correcting a protrusion defect on a color filter forming substrate or an intermediate substrate for producing the color filter forming substrate.

A liquid crystal display element usually has a structure in which two substrates having electrodes are opposed to each other and a liquid crystal is sandwiched between the two substrates. In order to keep the distance between the two substrates constant, Plastic beads having a uniform diameter are interspersed between the two substrates as spacers for spacing control.
In recent years, along with the increase in size and quality of liquid crystal display elements, spacer columnar structures (hereinafter referred to as columnar structures) formed at predetermined positions on a substrate by photolithography of a photosensitive resin instead of scattered bead spacers. It is also called "spacer").
As a method for forming this columnar spacer, there is a method in which a photosensitive resin is applied on a color filter and formed by photolithography.
By substituting the columnar spacer, it is possible to significantly improve the uniform distribution, which is a defect of the bead spacer, the bead movement in the cell, and the contrast decrease due to the light leaking due to the disturbance of the orientation around the bead.
For this reason, also in the color filter forming substrate, the demand for the color filter forming substrate with columnar spacers is increasing.

Further, as a liquid crystal display element of higher quality display, a cell structure using the columnar spacer is provided, and an alignment control protrusion is provided, and an alignment division vertical alignment type (hereinafter also referred to as MVA mode or multiple alignment division type) is used. What to do has been proposed.
The MVA mode is extremely promising for executing a wide viewing angle and a high-speed response. By providing alignment control protrusions on the color filter surface on the color filter forming substrate, it is almost completely possible that light due to the disorder of alignment leaks. Can be prevented.

Accordingly, in order to manufacture an MVA mode liquid crystal display element, it is required to manufacture a color filter forming substrate in which the columnar spacer and the alignment control protrusion are arranged.
Then, for example, FIG. 5A shows a partial cross-section thereof, and FIG. 5B shows a plan view thereof. On the transparent substrate 111, the black matrix 112 on the transparent substrate, the colored layers 113a to 113c, the transparent conductive material. A color filter forming substrate 110 is manufactured in which a film 115, a column spacer 117 for controlling the liquid crystal interval, and an alignment control protrusion 116 for controlling the alignment of the liquid crystal are arranged in this order.
5B is a view as seen from the E1 side in FIG. 5A, and FIG. 5A is a view showing a cross section on the E2-E3 side in FIG. 5B.
In FIG. 5, reference numeral 114 denotes an overcoat layer, and 113A, 113B, and 113C denote a region of the first colored layer 113a, a region of the second colored layer 113b, and a region of the third colored layer 113c, respectively. The bold dotted line indicates the boundary between these regions.
Then, using such a color filter forming substrate, an MVA mode liquid crystal display panel as shown in FIG. 6 is manufactured.
In FIG. 6, 250 is a color filter forming substrate, 251 is a transparent substrate, 252 is a black matrix, 253a to 253c are colored layers, 254 is an overcoat layer, 255 is a transparent conductive film (ITO), 258 is a columnar spacer, 259 is an alignment control protrusion, 262 is a liquid crystal, 262a and 262b are alignment materials, 270 is a counter substrate, 271 is a transparent substrate, 272 is a transparent electrode, 280 is a diffusion plate, and 281 is a backlight.

In such a color filter forming substrate in which columnar spacers and alignment control protrusions are arranged for manufacturing an MVA mode liquid crystal display element, protrusion defects (both black defects) are formed in the process of forming the columnar spacers and alignment control protrusions. If this happens, it must be corrected.
On the other hand, a laser correction method for such a color filter forming substrate is proposed in Japanese Patent Laid-Open No. 2005-17486 (Patent Document 1) and the like.
The method described in Japanese Patent Laid-Open No. 2005-17486 is intended to provide a correction method capable of correcting black defects (hereinafter also referred to as protrusion defects) of columnar spacers and alignment control protrusions without damaging the transparent conductive film. Then, using a transfer film in which an absorption layer that absorbs the wavelength of the laser beam used for correction is laminated in a thin film shape, an absorption layer is formed on the black defect, and laser irradiation is performed. Therefore, there is a problem that the work of repairing the defect becomes complicated due to the need to dispose the absorption layer.
Japanese Patent Laid-Open No. 2005-17486

As described above, recently, as a liquid crystal display element of higher quality display, a cell structure using the columnar spacer is provided, and an alignment control projection is provided to provide an alignment division vertical alignment type (hereinafter also referred to as MVA mode). In particular, a black matrix on a transparent substrate, a colored layer, a transparent conductive film made of ITO, a column spacer made of a resin for controlling the liquid crystal spacing, and an alignment of liquid crystal used in this type of liquid crystal display panel In the production of the color filter forming substrate in which the alignment control protrusions made of resin for controlling the resin are arranged in this order, the columnar spacers made of resin and the black of the alignment control protrusions are made without damaging the transparent conductive film. There is a need for a laser beam correction method that can easily and surely correct a defect (protrusion defect). The present invention corresponds to this, and in the composite base material in which the base part made of ITO as the base and the resin part to be corrected is arranged on the base material in order from the surface side, the base layer is damaged. Therefore, an object of the present invention is to provide a defect correction method using a laser beam, which can easily and reliably correct a protrusion defect of a resin portion.
In particular, a black matrix on a transparent substrate, a colored layer, a transparent conductive film made of ITO, a column spacer made of a resin for controlling the liquid crystal spacing, and an alignment control protrusion made of a resin for controlling the alignment of the liquid crystal in this order, In the production of a color filter forming substrate for a display panel such as a color filter forming substrate to be disposed or an intermediate process substrate for producing the color filter forming substrate, a columnar shape made of resin without damaging the transparent conductive film It is an object of the present invention to provide a correction method using laser light that can be easily and reliably performed with a correction method that can correct black defects (protrusion defects) of spacers and alignment control protrusions.

The defect correction method using laser light according to the present invention is a method of correcting a resin part in a composite base material in which a base resin layer and a base layer made of ITO as a base are arranged on the base material in order from the surface side. A method for correcting protrusion defects, wherein protrusion defects are removed by irradiating laser light, wherein the irradiation intensity is light intensity (W / area) when the laser light is irradiated onto the composite substrate. Control the irradiation intensity that can remove the resin part, and the irradiation intensity that does not damage the underlying layer. Repeated shot (pulse) irradiation is performed on the area containing the protrusion defect to remove the protrusion defect. Then, the protrusion defect removal is performed to expose the base layer of the protrusion defect region. During the repeated shot (pulse) irradiation, the light intensity (W / area) is changed in the middle. Irradiate with higher light intensity , Is characterized in that irradiation is performed to the end to the light intensity to be low from the partially exposed underlying.
In the defect correction method using the laser beam, the irradiation intensity is controlled by transmittance control using a transmittance variable filter (also referred to as an attenuator or an attenuator) that attenuates and adjusts the output of light from the laser light source. And / or by reducing magnification control of a lens system that projects a laser beam in a reduced scale and irradiates the composite substrate.
Further, in any of the above-described defect correction methods using laser light, the composite base material is a color filter forming substrate for a display panel or an intermediate substrate for producing the color filter forming substrate. The resin part is either a column spacer or an alignment control protrusion.
The defect correction method using laser light according to any one of claims 3 to 4, wherein the wavelength of the laser light is 355 nm or less.
The defect correction method using laser light according to any one of the above, wherein after the protrusion defect removal, a residue newly generated by laser irradiation and remaining in the vicinity of the protrusion defect area can be removed. The residue is removed by performing shot (pulse) irradiation at least once at an irradiation intensity that does not damage the underlying layer. Usually, since the cycle of shot irradiation is in the range of about 1 (shot / second) to 30 (shot / second), the number of shot irradiations more than the practical level, for example, whether there is damage due to 10,000 or more shot irradiations. to decide.
Here, “irradiation intensity that does not damage the underlying layer” means that the irradiation intensity does not damage the underlying layer no matter how many times the shot irradiation is performed at a practical level, and removal by irradiation does not occur. Irradiation does not cause damage due to absorbed heat.
Further, here, the protrusion defect is a defect portion that is excessively formed in a portion other than the normal formation region by the resin of the resin portion, and is also called a black defect and is continuous to the normal formation region. And those separated from the formation region.
Here, A and / or B means to include any case of A, A and B, or B.

(Function)
In this way, the defect correction method using laser light of the present invention is a composite base material in which a base part made of ITO, which is a base of the resin part to be corrected, and its base is arranged on the base material in order from the surface side. It is possible to provide a defect correction method using a laser beam that can easily and reliably correct a protrusion defect of a resin portion without damaging the underlying layer.
Specifically, the irradiation intensity, which is the light intensity (W / area) when the laser beam is irradiated onto the composite substrate, is controlled so that the resin portion can be removed and the underlying layer is damaged. As an irradiation intensity that does not exist, a shot defect is removed by repeatedly performing shot (pulse) irradiation on a region including a projection defect, removing the projection defect, and exposing a base layer of the projection defect region . During the repeated shot (pulse) irradiation, the light intensity (W / area) is changed during the process. At first, the light is irradiated with a higher light intensity, and the light intensity is increased after the ground is partially exposed. This is achieved by lowering the irradiation to the end .
The intensity of the laser beam can be controlled by controlling the transmittance with a variable transmittance filter (also referred to as an attenuator or attenuator) that attenuates and adjusts the output of the light from the laser light source, and / or by reducing and projecting the laser beam. By controlling the reduction magnification of the lens system that irradiates the substrate, the intensity of the irradiated laser beam can be easily controlled within a desired range by adopting the form of the invention of claim 2. It is possible.
For example, the output from the laser light source is irradiated with the underlying layer while changing the transmittance rank with a transmission variable filter, and the one-rank transmittance is small from the lowest transmittance rank that damages the underlying layer. The irradiation intensity in the rank irradiation is obtained as the first irradiation intensity, and the resin portion (projection defect is also the same material) is irradiated at an output lower than the first irradiation intensity to remove the resin portion (projection defect). The irradiation intensity in irradiation with the lowest possible transmittance rank is obtained as the second irradiation intensity, and the output of the laser light is controlled by the transmission variable filter so that it is between the first irradiation intensity and the second irradiation intensity. Set the irradiation intensity and correct the defect.
Examples of the composite base material include a color filter forming substrate for a display panel or an intermediate process substrate for producing the color filter forming substrate.
In particular, this is effective when the resin portion is either a column spacer or an alignment control protrusion.
As such a composite base material, a black matrix, a colored layer, a transparent conductive film made of ITO on a transparent substrate, a column spacer made of a resin for controlling the liquid crystal spacing, an orientation control made of a resin for controlling the orientation of the liquid crystal. An MVA mode color filter forming substrate in which the protrusions are arranged in this order, and a substrate in an intermediate process for producing the same are mentioned.
Further, by adopting the form of the invention of claim 5 in which the wavelength of the laser light is 355 nm or less, in the color filter forming substrate for a display panel or an intermediate process substrate for producing the color filter forming substrate, ITO It is possible to reduce the absorption of the underlying color filter of the base and the colored layer of the black matrix, and there is no influence of heat due to the absorption.
Note that in in that a repetitive shot (pulse) irradiation, during, and change the size of the aperture, by to Rukoto and forms may varying an irradiation area, so as not rely much laser as possible base, possible resin The area size of the irradiation region can be changed in the middle of processing so as to avoid the irradiation to the part that has been removed.
Further, in the inside of the repetition of the shot (pulse) irradiation, middle, by the form of changing the light intensity (W / area), while allowing adjustment of the working time of projection defect removal, underlying (ITO) Irradiation can be performed in consideration of the influence on the lower part.
For example, at first, irradiate with high light intensity, and after partially exposing the ground, lower the light intensity and irradiate to the end, thereby shortening the work time for removing the protrusion defect as much as possible, The influence on the lower part of the base (ITO) can be reduced.
In addition, after removing the protrusion defect, the irradiation intensity that can remove the residue newly generated by laser light irradiation and remaining in the vicinity of the protrusion defect area area, and the irradiation intensity that does not damage the underlayer is once. or performs shot (pulse) irradiation, removing the residue by the form of the invention of claim 6, after the protrusion defect removal, removing the residual such as newly generated resin by laser beam irradiation Is possible.

The present invention, as described above, damages the base layer in the composite base material in which the base part made of ITO as the base and the resin part to be corrected is arranged in order from the surface side on the base. In addition, it is possible to provide a defect correction method using laser light that can easily and reliably correct the protrusion defect of the resin portion.
In particular, a black matrix on a transparent substrate, a colored layer, a transparent conductive film made of ITO, a column spacer made of a resin for controlling the liquid crystal spacing, and an alignment control protrusion made of a resin for controlling the alignment of the liquid crystal in this order, In the production of a color filter forming substrate for a display panel such as a color filter forming substrate to be disposed or an intermediate process substrate for producing the color filter forming substrate, a columnar shape made of resin without damaging the transparent conductive film It is possible to provide a correction method using laser light that can be easily and reliably performed with a correction method that can correct black defects (protrusion defects) of spacers and alignment control protrusions.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1A is a schematic diagram showing an example of an embodiment of a defect correction method using a laser beam according to the present invention, and FIG. 1B is a projection defect and laser beam irradiation shown in FIG. FIG. 1 (c) is a diagram showing a protrusion defect of another shape and a laser light irradiation region, FIG. 2 is a schematic configuration diagram showing an example of a defect correcting device, and FIG. FIG. 4A is a simplified diagram showing the laser beam optical system of the defect correction apparatus shown in FIG. 2, and FIG. 4A is a flowchart showing an example of how to determine the range of irradiation intensity for the underlayer made of ITO. FIG. 4B is a flowchart showing an example of how to determine the range of irradiation intensity for the resin part.
In FIG. 4, S1 to S8 and S11 to S18 represent processing steps.
1-4, 10 is a color filter forming substrate (also referred to as a composite substrate), 11 is a transparent substrate (here, a quartz substrate), 12 is a black matrix, 13a is a first colored layer, and 13b is a second substrate. A colored layer, 13c is a third colored layer, 14 is an overcoat layer (also referred to as a planarizing layer), 15 is an underlayer (here ITO film), 16 is an alignment control protrusion (also referred to as a resin portion), 18, 18a is a protrusion defect (the same material as the alignment control protrusion), 20 is a substrate holder, 30 is an XY stage, 40 is a laser beam (here, a 355 nm wavelength YAG laser), and 41 and 41a are irradiation areas (also called shot areas). , 50 is a laser irradiation means, 51 is a laser generator, 52 is a variable transmittance filter (also referred to as an attenuator or attenuator), 53 is a lens, 54 is an aperture, 55 is a lens, and 56 is an objective. Lens, 60 is the Z-direction moving guide rail 70 is the control unit, 80 illumination intensity control database 90 is a display monitor.

First, an example of an embodiment of a defect correction method using laser light according to the present invention will be described with reference to FIG.
The defect correction method using laser light of this example is the resin part in the composite base material in which the base part 15 made of ITO, which is the base part, is disposed on the base part in order from the surface side. As shown in FIG. 2, the color filter forming substrate 10 is placed on the XY stage 30 as shown in FIG. Then, the protrusion defect 18 is removed by irradiation with the laser 40.
In particular, the irradiation intensity, which is the light intensity (W / area) when the laser light is irradiated onto the color filter forming substrate (composite base material) 10, is controlled so that the resin portion can be removed. In addition, as the irradiation intensity that does not damage the underlayer, the region including the projection defect 18 is repeatedly irradiated with shots (pulses) to remove the projection defect 18, and the underlayer 15 in the projection defect region is formed. The protrusion defect removal is performed.
In this example, after removing the projection defect, the irradiation intensity is such that dust newly generated by laser irradiation and remaining in the vicinity of the projection defect area can be removed, and the underlying layer is not damaged. At the irradiation intensity, shot (pulse) irradiation is performed at least once to remove the residue.
Here, the composite substrate is provided with a black matrix, a colored layer, a transparent conductive film, column spacers for controlling the liquid crystal spacing, and alignment control protrusions for controlling the alignment of the liquid crystal on the transparent substrate as shown in FIG. In this order, the MVA mode liquid crystal display panel forming color filter forming substrate 10 (10 shown in FIG. 1 and corresponding to 110 in FIG. 5) is arranged, and the protrusion defect of the resin portion to be corrected is subjected to orientation control. The color filter forming substrate (composite base material) 10 is provided with the black matrix 12 and the colored layers 13a to 13c below the base layer 15 made of ITO. Considering the influence of heat due to absorption, the third harmonic (355 nm) of the YAG laser is used as the laser beam.
The laser light wavelength is not limited to this as long as it is 355 nm or less.
Here, quartz glass of 100% silicon dioxide is used as the transparent substrate 11, but a plastic substrate and non-alkali glass are appropriately used as the transparent substrate.
Further, as the black matrix 12 and the colored layers 13a to 13c, a colored layer formed by photolithography by a pigment dispersion method is used, but is not limited thereto.
As the underlayer 15, a sputtered ITO film is used.
Here, the column spacers for controlling the liquid crystal spacing (see 117 in FIG. 5) and the alignment control protrusions 16 are each formed by making a negative photosensitive agent.

In addition to the drive system (XY stage 30, Z-direction moving guide rail 60) and laser irradiation means 50, the defect correction apparatus shown in FIG. 2 includes a display monitor 90 as confirmation means for confirming the state of the defective portion. A database 80 for controlling the irradiation intensity for facilitating the control of the irradiation intensity is provided, but each unit is controlled by the control unit 70 to perform a predetermined irradiation operation.
As shown in FIG. 3, the laser irradiation means 50 includes a laser light generator 51, a transmittance variable filter 52, a lens 53, an aperture 54 for shaping laser light, a lens 55, an objective lens 56, and the like. An optical system is formed, and the shaped laser light is collected and irradiated by the objective lens 56. The shutter, filter, half mirror, total reflection mirror, etc. for controlling the irradiation shot of the laser light are also clearly shown. Not provided, but provided as needed.
Here, a light source and an imaging device are incorporated so that an image can be obtained on an observation or display monitor 90 via a half mirror in the optical system of the laser irradiation means 50.
Further, the irradiation intensity control database 80 is a database of irradiation intensity that can remove the resin portion and that does not damage the underlayer in advance. The irradiation area size also provides a guideline that can be adjusted to a predetermined controlled irradiation intensity.
For example, in the optical system shown in FIG. 3, when the irradiation intensity is adjusted only by the transmittance level of the transmittance variable filter 52 and the reduction magnification of the objective lens at a predetermined aperture opening, the transmittance variable filter 52. As a parameter, the level of transmittance and the reduction magnification of the objective lens can be set as conditions for the irradiation intensity within a desired range for various resin member qualities.
In addition, the defect correction apparatus shown in FIG. 2 has a mechanism that controls the aperture opening and can change the area size without using the objective lens 56, that is, without changing the reduction magnification, although not explicitly shown. I have.
Thereby, the irradiation area can be easily changed with the same irradiation intensity, and the defect can be removed by avoiding the irradiation to the part where the resin is removed as much as possible so as not to apply the laser as much as possible to the base.

In the defect correction method using the laser beam of this example, as described above, the projection defect has an irradiation intensity that can be controlled to remove the resin portion 16 and that does not damage the underlying layer 15. 18 to the region containing the repeats performs shot (pulse) irradiation to remove the protrusion defect 18, to expose the underlying layer 15 of the projection defect region, and performs projection defect removal.
As shown in FIG. 1B, if the projection defect is smaller than the irradiation region (also referred to as a shot region) and is sufficiently away from the alignment control projection 16, the irradiation region 41 is defined as the alignment control projection 16. The region including the entire projection defect 18 is separated from the substrate, and the irradiation region is not shifted, and the shot (pulse) irradiation is repeatedly performed to remove the projection defect 18, and the underlying layer 15 of the projection defect region is formed. Expose.
Further, as shown in FIG. 1C, if the projection defect is smaller than the irradiation region (also referred to as a shot region), but is in a state connected to the orientation control projection 16, the orientation control projection 16 A region including the entire projection defect 18 is formed along the outer shape of the projection, and shot (pulse) irradiation is repeatedly performed without shifting the irradiation region, the projection defect 18 is removed, and the base layer 15 in the projection defect region is exposed.
Although not specified, in the defect correction apparatus shown in FIG. 2, the irradiation area can be rotated by the optical system.
Based on the above-described defect correction method, when the projection defect is large in size, the shot area is divided as necessary and correction is performed in the same manner as described above.

Next, an example of how to determine the irradiation intensity will be briefly described with reference to FIG.
First, the range of irradiation illuminance with respect to the underlayer 15 made of ITO is determined as follows based on FIG.
In order to simplify the explanation, here, the irradiation intensity is determined by the transmittance level (also referred to as a step) of the transmittance variable filter 52 and the reduction magnification of the objective lens, and the reduction magnification of the objective lens is fixed. To do.
First, the transmittance level (also referred to as a step) of the transmittance variable filter 52 is set to L _1n which is the lowest output. (S1-S2)
Here, the transmittance level L ₁₁ is selected in advance so that the underlying layer is not damaged at L ₁₁ which is the lowest output.
Here, it is assumed that the transmittance increases by one rank in the order of L ₁₁ , L ₁₂ , L ₁₃ .
Next, at the transmittance level L ₁₁ , the base layer 15 made of ITO is irradiated with shots a predetermined number of times N1. (S3)
Here, N1 is a large number (not practical level) that is not implemented in normal correction, for example, 10,000 times or more.
Then, after irradiation, it is checked whether or not the underlying layer 15 is damaged (S4). If there is no damage, the transmittance level (also referred to as a step) of the transmittance variable filter 52 is increased. The transmission level is set to L ₁₂ which is one rank higher in the direction. (S5 to S6)
Further, at the transmittance level L ₁₂ , the base layer 15 made of ITO is irradiated with shots a predetermined number of times N (S 3), and if there is damage, transmission is performed from the transmittance level L ₁₂ at this time. the level L ₁₁ and the first transmission level for irradiation intensity setting. (S7)
On the other hand, after the irradiation, it is checked whether or not the underlying layer 15 is damaged (S4). If there is no damage, the transmittance level (also referred to as a step) of the transmittance variable filter 52 is increased. While setting the transmittance level one rank higher in the direction (S5 to S6), the processing steps of Step S3 to Step S6 are repeated until damage is seen in Step S4, and from the transmittance level L _1n at this time The transmission level L _{1 (n−1)} is set as the first irradiation intensity setting transmittance level. (S7)
In this way, the transmittance level LA for setting the first irradiation intensity is obtained.
The range of irradiation illuminance on the underlayer 15 made of ITO is a transmission level equal to or lower than the transmission level LA.
In this example, the newly generated residue after the removal of the protrusion defect is removed with the same irradiation intensity as the removal of the protrusion defect.
Normally, the newly generated residue such as dust remaining in the vicinity of the projection defect area after the projection defect removal is the same as the resin part, and the removal of the residue is the removal of the projection defect. The same irradiation intensity can be used.

Next, the range of irradiation illuminance with respect to the resin portion (the alignment control protrusion 16 and the protrusion defect 18) is determined as follows based on FIG.
Here, the irradiation intensity is determined by the transmittance level (also referred to as a step) of the transmittance variable filter 52 and the reduction magnification of the objective lens, and the case where the reduction magnification of the objective lens is fixed will be described.
First, the transmittance level (also referred to as a step) of the transmittance variable filter 52 is set to L ₂₁ which is the lowest output. (S11-S12)
Here, in advance, so that the underlying layer is not damaged in L ₂₁ which is a minimum output, keep selecting the transmittance level L _21.
Here, it is assumed that the transmittance increases by one rank in the order of L ₂₁ , L ₂₂ , L ₂₃ .
Then, carried out in the transmittance level L _21, the resin portion 16, 18 made of ITO, the shots predetermined number of times N2. (S13)
Here, N2 is set to a large number (for example, 10,000 times or more) that is not implemented in normal correction.
Then, after irradiation, it is checked whether or not the resin parts 16 and 18 are damaged (S14). If there is no damage, the transmittance level of the transmittance variable filter 52 is set to 1 in the direction in which the transmittance increases. Set the transmittance level L ₂₂ to a higher rank. (S15-S16)
Further, at the transmittance level L ₂₂ , the resin portions 16 and 18 are irradiated with shots a predetermined number of times N 2 (S 13). If there is damage, the transmittance level L ₂ at this time is set to the second transmittance level L ₂ . The transmittance level is used for setting the irradiation intensity. (S17)
On the other hand, after the irradiation, it is checked whether or not the resin parts 16 and 18 are damaged (S14). If there is no damage, the transmittance level (also referred to as a step) of the transmittance variable filter 52 is determined. While setting the transmittance level one rank higher in the increasing direction (S15 to S16), the processing steps of Step S3 to Step S6 are repeated until damage is seen in Step S14, and the transmittance level L at this time is determined. _{Let 2n be} the transmittance level for setting the second irradiation intensity. (S17)
In this way, the transmittance level LB for setting the second irradiation intensity is obtained.
From this, the range of the illumination intensity with respect to the resin part becomes a transmission level equal to or higher than the transmission level LB.
Generally, the transmittance variable filter 52 has a transmittance level higher than that of the transmission level LB, and finally has an irradiation intensity at which the resin portion can be removed and an irradiation intensity that does not damage the underlying layer. The range of the transmission level is a level where the transmittance is higher than the transmission level B and the transmittance is lower than the transmission level LA.
The transmission level of the transmittance variable filter 52 is controlled within this range.
In this example, with a predetermined transmission level in this range, with a predetermined aperture size, the reduction magnification of the objective lens 56 is made constant, that is, the irradiation intensity is fixed, and repeated shot irradiation is performed to remove protrusion defects. Although it is what is performed, it is not limited to this.
During repeated shot (pulse) irradiation, the projection defect may be removed by changing the area size of the aperture opening while fixing the irradiation intensity without changing the reduction magnification of the objective lens 56. .
In this case, compared to this example, it takes time and effort to change the area size of the aperture opening, but to avoid irradiating the part where the resin has been removed as much as possible so as not to irradiate the substrate with as much laser as possible, it is possible to remove defects. It is possible.
In addition, in the present example or the above-described method, a mode in which the light intensity (W / area) is changed during the repeated shot (pulse) irradiation is also included.
In this case, for example, by irradiating at a high light intensity at the beginning, and by partially irradiating with a low light intensity after the substrate is partially exposed, the work time for removing the protrusion defects is minimized. In this way, the influence on the lower part of the base (ITO) can be reduced.

The present invention is not limited to the above.
For example, in this example, it is performed by an apparatus including a database (80 in FIG. 2) for controlling the irradiation intensity, but an apparatus including such a database is not necessarily required.
Further, the method of determining the level of the transmittance variable filter 52 for controlling the irradiation intensity shown in FIG. 4 has been described in the case of performing only by controlling the transmission level of the transmittance variable filter 52. In the case of changing the reduction magnification, it is necessary to change the transmission level of the transmittance variable filter 52 in accordance with the reduction magnification.

FIG. 1A is a schematic diagram showing an example of an embodiment of a defect correction method using a laser beam according to the present invention, and FIG. 1B is a projection defect and laser beam irradiation shown in FIG. FIG. 1C is a diagram showing a region having a different defect defect and a laser light irradiation region. It is the schematic block diagram which showed an example of the defect correction apparatus. It is the figure which simplified and showed the optical system of the laser beam of the defect correction apparatus shown in FIG. FIG. 4A is a flow chart showing an example of how to determine the range of irradiation intensity for the underlayer made of ITO, and FIG. 4B shows how to determine the range of irradiation intensity for the resin portion. It is the flowchart which showed one example. FIG. 5A shows a partial cross section of an example of a color filter forming substrate, and FIG. 5B is a view as seen from the E1 side in FIG. 5A. FIG. 6 is a cross-sectional view of an MVA mode liquid crystal display panel using the color filter forming substrate shown in FIG. 5.

Explanation of symbols

10 Color filter forming substrate (also called composite base material)
11 Transparent substrate (here, quartz substrate)
12 Black matrix 13a First colored layer 13b Second colored layer 13c Third colored layer 14 Overcoat layer (also referred to as planarization layer)
15 Underlayer (ITO film here)
16 Orientation control protrusion (also called resin part)
18, 18a Protrusion defect (same material as orientation control protrusion)
20 Substrate holder 30 XY stage 40 Laser light (here, YAG laser with a wavelength of 355 nm)
41, 41a Irradiation area (also called shot area)
50 Laser irradiation means 51 Laser generator 52 Variable transmittance filter (also called attenuator or attenuator)
53 Lens 54 Aperture 55 Lens 56 Objective lens 60 Z-direction moving guide rail 70 Control unit 80 Irradiation intensity control database 90 Display monitor 110 Color filter forming substrate 111 Transparent substrate 112 Black matrix 113a to 113c Colored layer 113A First colored layer Region 113B second colored layer region 113C third colored layer region 114 overcoat layer 115 transparent conductive film 116 alignment control protrusion 117 liquid crystal interval control column spacer 250 color filter forming substrate 251 transparent substrate 252 black matrix 253a to 253c Colored layer 254 Overcoat layer 255 Transparent conductive film (ITO)
258 Columnar spacer 259 Alignment control protrusion 262 Liquid crystal 262a, 262b Alignment material 270 Counter substrate 271 Transparent substrate 272 Transparent electrode 280 Diffuser 281 Backlight

Claims (6)

By irradiating laser beam on the protrusion defect of the resin part in the composite base material in which the resin part to be corrected and the base layer made of ITO which is the base are arranged on the base material in order from the surface side. A method for correcting protrusion defects, wherein the irradiation intensity is a light intensity (W / area) when the laser beam is irradiated onto the composite substrate, and the irradiation intensity that can remove the resin portion. In addition, as an irradiation intensity that does not damage the underlying layer, shot (pulse) irradiation is repeatedly performed on the region including the projecting defect, the projecting defect is removed, and the underlying layer of the projecting defect region is exposed. In order to remove the protrusion defect , during the repeated shot (pulse) irradiation, the light intensity (W / area) is changed in the middle. Light intensity after the ground is exposed Defect correction method by the laser beam, characterized in that irradiation is performed lowered into to the end. 2. The defect correction method using laser light according to claim 1, wherein the irradiation intensity is controlled by transmittance control using a transmittance variable filter (also referred to as an attenuator or attenuator) for adjusting attenuation of light output from the laser light source. And / or a reduction correction control of a lens system for projecting a laser beam in a reduced scale and irradiating the laser beam onto the composite substrate.   3. The defect correction method using laser light according to claim 1, wherein the composite base material is a color filter forming substrate for a display panel or an intermediate step for producing the color filter forming substrate. A defect correction method using a laser beam, which is a substrate.   4. The defect correction method using laser light according to claim 3, wherein the resin portion is either a column spacer or an alignment control protrusion.   5. The defect correction method using a laser beam according to claim 3, wherein the wavelength of the laser beam is 355 nm or less. 6. The defect correction method using laser light according to claim 1 , wherein the residue remaining in the vicinity of the protrusion defect area area newly generated by laser irradiation after the protrusion defect removal . in irradiation intensity capable of removing, and, at an irradiation intensity that does not damage the underlying layer, one or more times, performs shot (pulse) irradiation, defect correction method by the laser beam, characterized in that the removal of the residue.

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