JP2012141430A - Method for manufacturing color filter and color filter - Google Patents

Abstract

A method of manufacturing a color filter capable of forming a first layer on a glass substrate by exposure using a small mask continuous exposure method is provided.
In a forming step, an alignment mark is formed by laser marking on a glass substrate on which a first layer is not formed. In the applying step 20, a photosensitive resist is applied to the surface of the glass substrate on which the alignment mark is formed. The exposure step 30 reads the alignment mark from the back side of the glass substrate while transporting the glass substrate coated with the resist, and adjusts the position of the exposure heads 33 and 34 to adjust the surface of the glass substrate by a small mask continuous exposure method. Exposure. In the developing step 40, the exposed surface of the glass substrate is developed to form a first layer.
[Selection] Figure 1

Description

  The present invention relates to a method for producing a color filter, and more particularly to a technique for efficiently transferring a mask pattern onto a glass substrate.

  In the manufacturing process of color filters used for liquid crystal televisions and the like, a small mask continuous exposure method that repeatedly uses a small mask smaller than the display pixel area is employed for the purpose of suppressing an increase in mask cost accompanying an increase in the size of the panel. . In the small mask continuous exposure method, for example, an EGIS (Exposure System Guided by Image Sensor) that forms a stripe pattern or a dot pattern by transferring the mask pattern onto the glass substrate a plurality of times while scanning the exposure head on the glass substrate. ) There are exposure methods.

  In the EGIS exposure method, the first layer (herein referred to as “black matrix layer”, hereinafter referred to as “BM layer”) formed on the surface of the glass substrate is recognized by the camera as needed, and the second layer is based on the pattern of the first layer. This is a method for transferring the mask pattern after the first layer. A camera that reads the first layer and an exposure head that uses a small mask are integrated, and the position information of the first layer read by the camera is used to adjust the position of the exposure head. High positional accuracy is ensured by feedback.

JP 2006-292955 A

  However, when the first layer is formed on the surface of the glass substrate, there is no reference pattern, so the first layer cannot be formed by the EGIS exposure method. Therefore, the first layer is usually used for proximity exposure in which exposure is performed in a state where the mask and the work (glass substrate) are not in contact with each other slightly apart, and the mask image is applied to the work (glass substrate) using an optical system such as a lens. ), And is formed by projection exposure or the like for non-contact exposure.

  Therefore, the present invention provides a method for manufacturing a color filter capable of forming a first layer by exposing the glass substrate without the first layer by a small mask continuous exposure method, and a method for manufacturing the color filter. An object is to provide a manufactured color filter.

The present invention is directed to a method for manufacturing a color filter. And in order to solve the said subject, the manufacturing method of the color filter of this invention includes a formation process, an application | coating process, an exposure process, and a image development process.
In the forming step, an alignment mark is formed by laser marking on a glass substrate on which the first layer is not formed. In the applying step, a photosensitive resist is applied to the surface of the glass substrate on which the alignment mark is formed in the forming step. In the exposure process, the surface of the glass substrate is continuously exposed to a small mask while adjusting the position of the exposure head by reading the alignment mark from the back side of the glass substrate while transporting the glass substrate coated with the resist in the coating process. Exposure is performed by a method. In the development step, the surface of the glass substrate exposed in the exposure step is developed using a developer to form a first layer.

Preferably, in the forming step, the alignment mark is formed at a position outside the pixel arrangement region that has a predetermined relationship with the origin of the glass substrate.
Preferably, the alignment mark is a set of points formed by laser irradiation in the forming step, and each point is recognized as a white point by irregularly reflecting light, and the exposure step is performed on the conveyance path of the glass substrate. The position of the alignment mark may be detected by recognizing the white point by an optical sensor arranged below.

Preferably, in the exposure step, encoder information indicating a mechanical operation amount of the transfer device is acquired from an encoder provided in the transfer device of the glass substrate, and optical sensor information indicating a movement amount of the alignment mark is acquired from the optical sensor. Then, the encoder information and the optical sensor information may be compared to detect a mechanical shift including yawing caused by the distortion of the conveyance axis, and fed back to the position adjustment of the exposure head.
Preferably, in the forming step, the alignment mark is formed in the glass substrate by inner marking that does not generate any particles.

  The present invention is also directed to a color filter. And in order to solve the said subject, the color filter of this invention is a color filter manufactured by the manufacturing method of one of said color filters.

  If the manufacturing method of the present invention is used, an alignment mark is formed in advance on the glass substrate by laser marking, so that the first layer can be formed on the glass substrate by exposure with a small mask continuous exposure method based on the alignment mark. it can.

Therefore, the mask cost can be greatly reduced as compared with the case where the first layer is formed on the glass substrate by proximity exposure or projection exposure.
Further, in the manufacturing method of the present invention, since the movement amount of the alignment mark can be fed back to the position adjustment of the exposure head during exposure, exposure can be performed with high accuracy.

The figure which shows the outline of the manufacturing method of the color filter which concerns on 1st Embodiment. The figure which shows the glass substrate in which the alignment mark was formed in the formation process 10. The figure which shows a mode that the surface of a glass substrate is exposed in the exposure process 30. FIG. 3 is a view from the side (direction X in FIG. 3).

[First Embodiment]
In the color filter manufacturing method according to the first embodiment, an alignment mark is formed by laser marking before the exposure process on a glass substrate on which the first layer is not formed. By reading the alignment mark from the back side of the substrate, the surface of the glass substrate is exposed by the small mask continuous exposure method while adjusting the position of the exposure head, thereby forming the first layer.

<Configuration>
FIG. 1 is a diagram showing an outline of a method for manufacturing a color filter according to the first embodiment.
As shown in FIG. 1, the manufacturing method 1 of the color filter which concerns on 1st Embodiment is the exposure process exposed by the formation process 10 which forms an alignment mark, the application | coating process 20 which apply | coats a resist, and a small mask continuous exposure system. The process 30 and the image development process 40 which develops using a developing solution are included.

The forming step 10 is a step of previously forming a guide alignment mark by laser marking on a glass substrate on which the first layer has not yet been formed.
Specifically, the forming step 10 uses a marking device 11 including a SHG (Second harmonic generation) laser head 12 and a stage 13 having a function of holding and moving the glass substrate, and relative to the origin of the glass substrate. An alignment mark is formed at a position outside the pixel arrangement region having a predetermined relationship.

Here, the stage 13 provided in the marking device 11 includes a chuck mechanism 14 for reliably holding the glass substrate, and a moving mechanism capable of arbitrarily changing the relative position between the held glass substrate and the SHG laser head 12. 15. A commercially available device (laser titler) can be used as the marking device 11.
The origin of the glass substrate is a virtual point based on the outer shape of the glass substrate. For example, the intersection of the upper side and the left side of one main surface of the glass substrate can be used as the origin.

In addition, the alignment mark formed in the forming step 10 is a set of points formed by clean inner marking in which no particles are generated inside the raw glass substrate by irradiation of the SHG laser (532 nm), respectively. Since this point irregularly reflects light, it is recognized as a white point by the naked eye or a sensor.
As described above, the method of forming the alignment mark using the laser has the following reasons.
As described above, since the first layer is usually a BM layer and has a high density of black, if the alignment mark is made of a general black ink or metal, optical reading becomes difficult after the first layer of resist is applied. End up. Therefore, the alignment mark is formed so as to be recognized as white using a laser, so that optical reading can be performed without any problem even after the first layer of resist is applied. In addition, by forming the alignment mark with the inner marking inside the glass substrate using a laser, regardless of which principal surface is formed on the glass substrate, the focal length must be different between the resist and the alignment mark. become. Therefore, the difference in focal length is used to make it possible to optically read the alignment mark more stably.
FIG. 2 is a view showing the glass substrate on which the alignment mark is formed in the forming step 10.

As shown in FIG. 2, an alignment mark 102 is formed at an end position not included in the pixel arrangement region 101 in the central portion of the glass substrate 100 having a square main surface. Here, the alignment mark 102 is intermittently formed along each of two sides parallel to the substrate transport direction in which the glass substrate 100 is transported in the exposure step 30.
Instead of the SHG laser, a higher-order harmonic laser such as a THHG (Third Harmonic Generation) laser or an FHG (Fourth Harmonic Generation) laser may be used, or another laser may be used.

In the applying step 20, a photosensitive resist is applied to a uniform thickness by a spinless coater or the like at a position corresponding to a pixel arrangement region on the surface of the glass substrate on which the alignment mark is formed in the forming step. Here, a resist containing a volatile solvent is used, and after application, the solvent component is vaporized and dried. Also, in the coating step 20, when the upper layer is formed after the lower layer is formed, the resist is repeatedly applied in the same manner.
The exposure process 30 is a small mask covering the surface of the glass substrate while adjusting the position of the exposure head by reading the alignment mark from the back side of the glass substrate while conveying the glass substrate coated with the resist in the coating process 20. Exposure is performed by a continuous exposure method. Further, in the exposure step 30, when the upper layer is formed after the lower layer is formed, the surface of the glass substrate is repeatedly exposed by the small mask continuous exposure method while reading the pattern of the lower layer or reading the alignment mark. To do. Here, the alignment mark is read from the back side of the glass substrate because the alignment mark cannot be read from the surface when a resist is applied to the surface of the glass substrate.

FIG. 3 is a diagram showing how the surface of the glass substrate is exposed in the exposure step 30.
4 is a view of FIG. 3 as viewed from the side (direction X in FIG. 3).
Specifically, the exposure step 30 includes a camera 32 having an optical sensor for reading an alignment mark, an exposure head A row 33, an exposure head B row 34, and a stage 35 having a function of holding and moving the glass substrate. The surface of the glass substrate is exposed using an EGIS exposure apparatus 31 including the above.
Here, the stage 35 provided in the EGIS exposure apparatus 31 includes a chuck mechanism 36 for reliably holding the glass substrate, and a relative position between the held glass substrate and the exposure head A row 33 and the exposure head B row 34. The moving mechanism 37 can be arbitrarily changed, and the encoder 38 outputs a mechanical operation amount of the moving mechanism 37.

  Further, the exposure step 30 acquires encoder information indicating the mechanical operation amount of the moving mechanism 37 from the encoder 38, acquires optical sensor information indicating the movement amount of the alignment mark from the camera 32, and acquires the encoder information and the optical sensor. By comparing the information and detecting the mechanical deviation from the difference between the mechanical movement amount and the actual movement amount of the glass substrate, and feeding it back to the position adjustment of the exposure head, the mechanical movement amount is reduced. To compensate. Here, the mechanical misalignment refers to the misalignment of the glass substrate due to the yawing effect due to the distortion of the transport axis, the amount of movement of the glass substrate in the cross scan direction, and the angle θ between the scan direction and the cross scan direction. The amount of misalignment.

In the developing step 40, the surface of the glass substrate exposed in the exposing step 30 is developed using a developer to form a first layer. More specifically, an unexposed portion is developed with an alkali developer, and baked in an oven after washing, thereby forming a BM layer serving as a first layer on the surface of the raw glass substrate. In the developing step 40, when the upper layer is formed after the lower layer is formed, the upper layer is formed by repeatedly developing in the same manner.
When it is necessary to further form an upper layer, the coating step 20, the exposure step 30, and the development step 40 are repeatedly performed, and when all the layers are formed, they are transferred to the next step.

<Summary>
As described above, if the method for manufacturing a color filter according to the present embodiment is used, an alignment mark is formed in advance on a glass substrate by laser marking. Therefore, the first layer is exposed by a small mask continuous exposure method based on the alignment mark. can do. Therefore, the mask cost can be greatly reduced.

  The method for producing a color filter of the present invention can be used for a color filter used in a liquid crystal television or the like. In particular, the larger the screen, the higher the effect of reducing the mask cost. Moreover, the manufacturing method of the color filter of this invention can be used not only for a color filter but for manufacture of all the things which are exposed by the small mask continuous exposure system after the 2nd layer.

DESCRIPTION OF SYMBOLS 1 Color filter manufacturing method 10 Formation process 11 Marking apparatus 12 SHG laser head 13 Stage 14 Chuck mechanism 15 Moving mechanism 20 Coating process 30 Exposure process 31 EGIS exposure apparatus 32 Camera 33 Exposure head A row 34 Exposure head B row 35 Stage 36 Chuck Mechanism 37 Moving mechanism 38 Encoder 40 Development process 100 Glass substrate 101 Pixel arrangement area 102 Alignment mark

Claims (6)

A color filter manufacturing method comprising:
A forming step of forming an alignment mark by laser marking on a glass substrate on which no first layer is formed on the surface;
An application step of applying a photosensitive resist on the surface of the glass substrate on which the alignment mark is formed by the formation step;
Small mask continuous exposure of the surface of the glass substrate while adjusting the position of the exposure head by reading the alignment mark from the back side of the glass substrate while transporting the glass substrate coated with the resist in the coating step An exposure process for exposing by a method;
And a developing step of developing the surface of the glass substrate exposed in the exposing step using a developer to form a first layer. The forming step includes
2. The method of manufacturing a color filter according to claim 1, wherein the alignment mark is formed at a position outside a pixel arrangement region that has a predetermined relationship with the origin of the glass substrate. The alignment mark is a set of points formed by laser irradiation in the forming step, and each point is recognized as a white point by irregularly reflecting light,
The exposure step includes
The method for manufacturing a color filter according to claim 1, wherein the position of the alignment mark is detected by recognizing the white point by an optical sensor disposed below a conveyance path of the glass substrate. The exposure step includes
Encoder information indicating a mechanical operation amount of the transfer device is acquired from an encoder provided in the transfer device of the glass substrate, optical sensor information indicating a movement amount of the alignment mark is acquired from the optical sensor, and the encoder information The optical sensor information is compared with the optical sensor information to detect a mechanical shift including yawing caused by the distortion of the transport axis, and feed back to the position adjustment of the exposure head. A method for producing a color filter. The forming step includes
The method for producing a color filter according to claim 1, wherein the alignment mark is formed by inner marking in which no particles are generated inside the glass substrate.   The color filter manufactured by the manufacturing method of the color filter of any one of Claims 1-5.

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