JP2008009084A - Plotting method for color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plotting method for a color filter by which patterns of the second and the upper layers can be formed with high alignment accuracy following distortions of black matrix patterns formed by step exposure. <P>SOLUTION: The plotting method for the color filter comprises the steps of: applying step exposure to the black matrix patterns onto a substrate to form the black matrix patterns and forming four alignment marks outside four corner parts of the black matrix pattern at each of shots; reading the alignment marks on the substrate to obtain distortion data showing the extent of the distortion of the black matrix pattern at each of shots; and performing the exposure for forming patterns of the second and the upper layers on the scanned/moved substrate by using a scanning exposure device having a base equipped with a plurality of exposing heads. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a color filter manufacturing method, and more particularly to exposure in manufacturing a color filter used in a large color liquid crystal display device.

  Conventionally, in the manufacture of large color filters used in large color liquid crystal display devices, as a problem in the photolithography process, the cost for producing a large exposure mask is large in a batch exposure method using an original large exposure mask. There is. In order to solve this problem, an exposure method that does not require a large exposure mask has been developed, in which an exposure machine equipped with a plurality of exposure heads is used and scanning exposure is performed using a small exposure mask paired with each exposure head. ing. Such an exposure method is described in Patent Document 1 and Patent Document 2, for example.

However, the black matrix (first layer) formed by the step-and-repeat exposure method has a problem that pattern distortion occurs every shot exposure. For example, in the case of forming the second and subsequent patterns with a scanning exposure (drawing) apparatus having a plurality of heads, as shown in FIG. However, it is not possible to perform accurate exposure to form the second and subsequent patterns in accordance with the distortion of the black matrix pattern 32. In the figure, reference numeral 33 denotes an exposure head.
JP 2000-347020 A JP 2005-331542 A

  The present invention has been made under the circumstances as described above, and is a color filter capable of forming the second and subsequent layers with high alignment accuracy following the distortion of the black matrix pattern formed by step exposure. An object of the present invention is to provide a drawing method.

  In order to solve the above-described problems, the present invention forms a black matrix pattern by step-exposure of a black matrix pattern on a substrate, and four alignment marks are formed outside the four corner portions of the black matrix pattern of each shot. Scanning using a scanning exposure apparatus having a base having a plurality of exposure heads, a step of reading alignment marks on the substrate, obtaining distortion data indicating the degree of distortion of the black matrix pattern of each shot, and a plurality of exposure heads In the color filter drawing method comprising the step of performing exposure for forming a pattern for the second and subsequent layers on the moving substrate, the exposure for forming the pattern for the second and subsequent layers is performed for each shot. Depending on the black matrix pattern distortion data, Individually each exposure head, a method of rendering a color filter, which comprises carrying out while moving in a direction perpendicular to the scanning direction of movement of the substrate.

  Instead of the four alignment marks outside the four corners of the black matrix pattern, the four portions of the black matrix pattern itself of each shot can be used as alignment marks.

  In the above-described color filter drawing method, the alignment marks on the substrate can be read by three imaging units installed at positions corresponding to both ends and the center of the base substrate.

  Further, the distortion data indicating the degree of distortion of the black matrix pattern of each shot is obtained by moving the imaging unit so that the alignment pattern attached to the imaging unit matches the read alignment mark, It can be obtained by measuring the amount of movement.

  Further, the inclination of the imaging means can be managed by laser light irradiation from two directions, and the scanning movement direction of the substrate is controlled to be perpendicular to the arrangement direction of the plurality of exposure heads. can do. In this case, the direction of the scan movement of the substrate is controlled by reading the stage mark provided on the stage on which the substrate is placed with another imaging means attached to the base and obtaining the deviation obtained thereby. This can be done by correcting the amount.

  According to the present invention, when a black matrix pattern formed by step exposure is subjected to scanning exposure by an exposure apparatus including a plurality of exposure heads to form a pattern for the second and subsequent layers, the black matrix pattern of each shot is formed. Even if there is distortion, the multiple exposure heads move individually according to the distortion, and follow the distortion of the black matrix pattern of each shot, so that the predetermined pattern is highly aligned on the black matrix pattern. Can be formed.

  Hereinafter, a color filter drawing method according to an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, six black matrix patterns 2 are formed on a large glass substrate 1 by six shots of shot 1 to shot 6 using a step exposure method. At that time, alignment marks M1 to M4 are formed outside the four corner portions for each shot. In the figure, reference numeral 3 denotes an exposure head.

  Next, an RGB pattern is formed on the black matrix pattern 2 thus formed using an exposure apparatus as shown in FIG. In FIG. 9, a plurality of exposure heads 3 are juxtaposed in parallel in a certain direction on a region to be exposed of the substrate 1 through a mask 22. Under these exposure heads 3, the substrate scans in the Y direction, and exposure of the exposed area on the substrate 1 is performed.

  In this exposure apparatus, alignment marks M attached to the substrate 1 are formed only at the four corners of the substrate for illustration, but actually four are formed for each black matrix pattern of each shot. ) And a stage-head calibration camera 15 for reading the alignment mark 17 formed on the stage 23 are arranged.

  FIG. 2 is a top view showing a head gantry 10 in which seven exposure heads 11 are arranged in a horizontal row. Each exposure head 11 can move independently in a direction perpendicular to the scanning direction of the glass substrate, and the amount of movement can be measured by a linear scale 12 attached to each exposure head 11.

  On one side of the head gantry 10, a first camera 13a is attached in the vicinity of the left end, a second camera 13b in the center, and a third camera 13c in the vicinity of the right end, and the cameras 13a, 13b, 13c can move independently in a direction perpendicular to the scanning direction of the glass substrate, and the amount of movement can be measured by linear scales 14a to 14c attached to the respective cameras 13a, 13b, and 13c.

  The first camera 13a is for reading the left alignment marks M1, M2 on the substrate 1, and the second camera 13b is for reading the alignment marks M3, M4, M1, M2 at the center. The third camera 13c is for reading the right alignment marks M3 and M4, both of which are substrate alignment cameras.

  As shown in FIG. 3, a reticle 21 having a pattern P for alignment with an alignment mark on the substrate 1 is attached to the substrate alignment cameras 13a, 13b, and 13c. The pattern P of the reticle 21 and the substrate The substrate alignment cameras 13a, 13b, and 13c are moved so that the upper alignment mark S coincides, and the amount of displacement is obtained by measuring the amount of movement with a linear scale, whereby the degree of distortion of the black matrix pattern 2 Is grasped. FIG. 4 shows a state in which the pattern P of the reticle 21 attached to the substrate alignment cameras 13a, 13b, and 13c and the alignment mark M on the substrate 1 coincide with each other.

  As shown in FIG. 3, the substrate alignment cameras 13a, 13b, and 13c are irradiated with laser light from two directions, and the inclinations of the substrate alignment cameras 13a, 13b, and 13c are managed.

  In order to grasp the degree of distortion of the black matrix pattern 2 as described above, the scanning direction of the stage needs to be perpendicular to the direction of the exposure head 11. As means for controlling the scanning direction of such a stage, the following configuration may be considered.

  That is, on the other side of the head gantry 10, the fourth camera 15a is attached to the left end and the fifth camera 15bc is attached to the right end. Each camera 15a, 15b can move independently in the direction perpendicular to the scanning direction of the glass substrate, and the amount of movement can be measured by the linear scales 16a, 16b attached to the respective cameras 15a, 15b. .

  These fourth and fifth cameras 15a and 15b are stage-head calibration cameras for reading the alignment marks formed on the stage. That is, as shown in FIG. 5, a plurality of alignment marks 17a and 17b are formed on both sides of the stage 23 in the scanning direction, and a plurality of alignment marks 18a are also formed on the front portion of the stage 23 in a direction perpendicular to the scanning direction. , 18b are formed, and the stage-head calibration cameras 15a, 15b are mounted with reticles having a predetermined pattern, similarly to the substrate alignment cameras 13a, 13b, 13c described above.

  In such a configuration, the stage-head calibration required for matching the alignment marks 17a, 17b, 18a, 18b on the stage 23 with the reticle patterns of the stage-head calibration cameras 15a, 15b while scanning the stage 23 is performed. By grasping the displacement amount of the alignment marks 17a, 17b, 18a, 18b from the movement amount of the motion camera 15a, 15b, the inclination and position of the stage scan can be grasped, and by correcting this, the exposure head It is possible to scan the stage in a direction completely perpendicular to the direction.

  As described above, after the degree of distortion of the black matrix pattern 2 is ascertained, a pattern after the second layer, for example, an RGB pattern, is formed following such distortion. The scanning exposure at that time is performed as shown in FIG.

  That is, based on the distortion information of the black matrix pattern 2, each of the seven exposure heads 11 is individually moved in a direction perpendicular to the scanning direction of the substrate in accordance with the degree of distortion. As a result, as shown in FIG. 6, the exposure head 11 follows the trajectories 31a, 31b, 31c, 31d, 31e, 31f, and 31g on the substrate. In FIG. 6, the solid rectangle indicates the design value black matrix pattern, and the broken line graphic indicates the distortion of the black matrix pattern.

  As is apparent from FIG. 6, the trajectories 31a, 31b, 31c, 31d, 31e, 31f, and 31g of the exposure head 11 individually follow the black matrix pattern having distortion, and in this way, It is possible to obtain a second and subsequent layer pattern, for example, an RGB pattern, adapted to the distortion of the black matrix pattern of the shot.

  The case where four alignment marks are formed outside the four corners of the black matrix pattern of each shot has been described above. However, the present invention is not limited to this. For example, the alignment mark may be formed outside the black matrix pattern. Alternatively, a part of the black matrix pattern itself can be used as an alignment mark. Such an example is shown in FIG.

  FIG. 7A shows a part of the black matrix pattern 2 having a black lattice shape. As shown in FIG. 7B in which the part A is enlarged, the corner B of the black matrix pattern 2 is used as an alignment mark. The distortion of the black matrix pattern can be measured by matching with the reticle pattern P attached to the cameras 13a, 13b, and 13c. The portion regarded as the alignment mark is not limited to the corner portion of the black matrix pattern, but a corner portion that is a part that can be easily detected is preferable for grasping the distortion of the black matrix pattern.

The top view which shows the state in which the black matrix pattern and the alignment mark were formed on the large sized glass substrate using the step exposure method. The figure which shows a head gantry provided with several exposure head and a camera. The figure which shows the state in which a camera reads the alignment mark on a board | substrate. The figure which shows the state which match | combined the pattern of the board | substrate alignment camera with the alignment mark. The figure which shows the state in which the stage-head calibration camera reads the alignment mark on a stage. The figure which shows the locus | trajectory of the exposure head which follows the distortion of a black matrix pattern. The figure which shows the state match | combined with the pattern of the board | substrate alignment camera, using the corner part of a black matrix pattern as an alignment mark. The top view which shows the state in which the black matrix pattern and the alignment mark were formed on the conventional large sized glass substrate using the step exposure method. 1 is a perspective view showing an outline of an exposure apparatus used in one embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,31 ... Large glass substrate, 2, 32 ... Black matrix pattern, 3,33 ... Exposure head, 11 ... Head gantry, 12, 14a-14c, 16a, 16b ... Linear scale, 13a, 13b, 13c ... Substrate alignment camera 15a, 15b ... stage-head calibration camera, 17a, 17b, 18a, 18b ... alignment mark, 21 ... reticle, 22 ... mask, 23 ... stage.

Claims (7)

Forming a black matrix pattern by step exposure of the black matrix pattern on the substrate, and forming four alignment marks outside the four corners of the black matrix pattern of each shot;
The substrate which scans and moves using a scanning exposure apparatus having a step of reading an alignment mark on the substrate and obtaining distortion data indicating a degree of distortion of the black matrix pattern of each shot, and a base having a plurality of exposure heads In the color filter drawing method comprising the step of performing exposure to form a pattern for the second and subsequent layers thereon,
The exposure for forming the pattern for the second and subsequent layers is individually moved in a direction orthogonal to the scanning movement direction of the substrate according to the distortion data of the black matrix pattern of each shot. A color filter drawing method characterized by being performed.   2. The color according to claim 1, wherein four portions of the black matrix pattern itself of each shot are used as alignment marks in place of the four alignment marks outside the four corner portions of the black matrix pattern. How to draw the filter.   3. The color according to claim 1, wherein the alignment mark on the substrate is read by three imaging units installed at positions corresponding to both end portions and a central portion of the base substrate. 4. How to draw the filter.   Displacement data indicating the degree of distortion of the black matrix pattern of each shot is moved by moving the imaging unit so that the alignment pattern attached to the imaging unit matches the read alignment mark, and the amount of movement The color filter drawing method according to claim 3, wherein the color filter drawing method is obtained by measuring   5. The color filter drawing method according to claim 4, wherein the inclination of the imaging means is managed by laser light irradiation from two directions.   6. The color filter drawing method according to claim 1, wherein a direction of scan movement of the substrate is controlled so as to be perpendicular to an arrangement direction of the plurality of exposure heads.   Control of the direction of scanning movement of the substrate is performed by reading a stage mark provided on the stage on which the substrate is placed by another imaging means attached to the base and correcting the amount of deviation obtained thereby. The color filter drawing method according to claim 6, wherein the drawing is performed.

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