KR101296495B1 - Exposing mask and method of exposing using the exposing mask - Google Patents

Abstract

An exposure mask and an exposure method are disclosed. The exposure mask includes a non-overlapping part including a first main pattern having a plurality of first sub-patterns having equal intervals, second main patterns disposed on one side of the non-overlapping part, and having a plurality of second sub-patterns. 3rd main patterns including a plurality of third sub-patterns disposed on the other side of the first overlapping portion and the non-overlapping portion where the distance between the second sub-patterns is constantly reduced as the distance from the first boundary formed with The second overlapping part may further include a second overlapping part in which a distance between the third sub-patterns decreases as it moves away from the second boundary forming the patch.

Description

Exposure mask and exposure method {EXPOSING MASK AND METHOD OF EXPOSING USING THE EXPOSING MASK}

1 to 4 are plan views and graphs showing masks for explaining a conventional stitch exposure method.

5 is a plan view illustrating an exposure mask according to an exemplary embodiment of the present invention.

FIG. 6 is an enlarged plan view of the first main pattern illustrated in FIG. 5.

FIG. 7 is a plan view illustrating the second main pattern and the second sub patterns illustrated in FIG. 5.

FIG. 8 is a plan view illustrating the third main pattern and the third sub patterns illustrated in FIG. 5.

9 is a cross-sectional view illustrating a substrate on which a first exposure process is performed on a non-overlapping region and an overlapping region by an exposure method according to an exemplary embodiment of the present invention.

FIG. 10 is a cross-sectional view illustrating a substrate on which a second exposure process is performed on an overlapping area by an exposure method according to an exemplary embodiment of the present invention.

FIG. 11 is a graph illustrating an interval between sub-patterns included in a second pattern formed by the first overlapping part and a third pattern formed by the second overlapping part.

<Explanation of symbols for the main parts of the drawings>

10: non-overlapping portion 20: first overlapping portion

30: second overlapping portion 5: first main pattern

15: second main pattern 25: third main pattern

7: first subpattern 18: second subpattern

28: third subpattern

The present invention relates to an exposure mask and an exposure method. More specifically, the present invention relates to an exposure mask and an exposure method which prevented a decrease in pattern uniformity due to divided exposure.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display panel, and more particularly, to an exposure mask capable of compensating for stitch unevenness due to divided exposure and an exposure method using the same.

A typical liquid crystal display device displays an image by adjusting the light transmittance of a liquid crystal having dielectric anisotropy using an electric field. To this end, the liquid crystal display device includes a liquid crystal display panel (hereinafter, referred to as a liquid crystal panel) having a liquid crystal cell matrix for displaying an image, and a driving circuit for driving the liquid crystal panel. BACKGROUND ART An active matrix type liquid crystal display device that independently drives liquid crystal cells using thin film transistors is widely used not only for display devices of personal computers (PCs) but also for televisions (hereinafter, referred to as TVs).

The liquid crystal panel includes a thin film transistor substrate and a color filter substrate facing each other, a liquid crystal injected between the two substrates, and a spacer for maintaining a cell gap between the two substrates.

The thin film transistor substrate includes a gate line and a data line, a thin film transistor formed of a switch element at each intersection of the gate lines and the data lines, a pixel electrode formed in a liquid crystal cell unit and connected to the thin film transistor, and the like applied thereon. Composed of aligned alignment films.

The color filter substrate includes color filters formed in units of liquid crystal cells, a black matrix for distinguishing between color filters and reflecting external light, a common electrode supplying a reference voltage to the liquid crystal cells in common, and an alignment layer applied thereon. It is composed.

The liquid crystal panel is completed by separately manufacturing the thin film transistor substrate and the color filter substrate, and then injecting and encapsulating the liquid crystal.

In such a liquid crystal panel, the thin film transistor substrate and the color filter substrate include a plurality of mask processes for pattern formation. Each mask process includes a thin film deposition process, a cleaning process, a photolithography process, an etching process, a photoresist stripping process, an inspection process, and the like. Here, a stitch exposure method for dividing and exposing the thin film transistor substrate and the color filter substrate when the liquid crystal panel is larger than the effective area of the exposure machine used in the photolithography process is used.

1 is a view for explaining a conventional stitch exposure method.

The substrate 10 illustrated in FIG. 1 means a substrate 10 in which a thin film (metal layer, insulating film, semiconductor layer, etc.) and a photoresist for patterning are stacked. The photoresist is patterned by transferring the pattern of the mask in an exposure process and then developing. In this case, when the substrate 10 is larger than the mask, the photoresist is exposed by the stitch exposure method of repeating the exposure process while moving the mask. Here, one exposure process unit using a mask is called a shot, and an exposure area of a substrate corresponding to one shot is called a shot area. For example, it can be seen that the photoresist of the substrate 10 shown in FIG. 1 is divided into first and second shot regions A and B and exposed. At this time, the left side and the right side of each of the first and second shot regions A and B form the same pattern as that of the center portion due to an exposure machine having a characteristic of decreasing light intensity differently from left and right sides or a mask in which alignment is incorrect. It is impossible to do. As a result, a size difference occurs between patterns formed in the boundary regions of the first and second shot regions A and B to cause stitch unevenness in the completed liquid crystal panel.

2 is a plan view illustrating a mask that improves the problem of FIG. 1.

In order to solve this problem, as shown in FIG. 2, the stitches are removed by having overlapping regions 12 overlapping boundary portions of the first and second shot regions A and B, as shown in FIG. 2. . In this case, as a method of overlapping the first and second shot regions A and B, a pattern is divided on both side regions of the mask, and both sides of the mask on which the pattern is divided are shared in the first and second shot processes. This is used. To this end, a method of dividing a pattern in both sides (hereinafter, overlapping) of the mask overlapping in the front and rear shots is performed by dividing the pattern in half and linearly changing the pattern amount (ie, pattern area). Forming method is used.

Referring to FIG. 3, the mask 20 includes non-overlapping portions 22 having patterns having a predetermined area, and overlapping portions 24 and 26 formed by separating the entire pattern by half on left and right sides of the non-overlapping portions 22. . The first and second shot regions A and B shown in FIG. 2 are repeatedly exposed using the mask 20. At this time, in the overlapping region 12 of the first and second shot regions A and B, half the pattern corresponding to the right overlapping portion 26 of the mask 20 in the first shot process is formed in the second shot process. The other half of the pattern corresponding to the left overlap 24 of the mask 20 is transferred. Accordingly, the difference in the pattern size due to the stitch exposure is reduced in half in the overlapping region 12 of the first and second shot regions A and B, but the stitch stain due to the remaining pattern size difference cannot be removed. There is this.

Referring to FIG. 4, the mask 30 includes a non-overlapping portion 32 in which a pattern of a predetermined area is formed, and overlapping portions 34 and 36 in which the pattern area decreases linearly as the non-overlapping portion 32 moves away from the non-overlapping portion 32. It is provided in the left and right sides of the non-overlapping part 32. Here, it can be seen that the overlapping portions 34 and 36 are linearly reduced in pattern area so as to be symmetrical with respect to the non-overlapping portion 32. The first and second shot regions A and B shown in FIG. 2 are repeatedly exposed using the mask 30. At this time, in the overlap region 12 of the first and second shot regions A and B, the pattern amount (pattern area) linearly corresponds to the right overlap portion 36 of the mask 30 in the first shot process. The decreasing pattern is transferred, and the pattern in which the pattern area linearly increases in correspondence with the left overlapping portion 34 of the mask 30 is transferred in the second shot process. Accordingly, in the overlapping region 12 of the first and second shot regions A and B, the difference in the pattern size is compensated for by the pattern area that changes linearly to increase or decrease to remove the spots.

However, in the mask 30, the start region of the right overlapping portion 36 adjacent to the non-overlapping portion 32 and the end region of the left overlapping portion 34 suddenly look from the side of the non-overlapping portion 32 in which the pattern area does not change. There is a problem of causing a change in brightness, that is, a stitch unevenness, which can be perceived by the eyes by forming a severe inflection as a portion where a change occurs in the pattern area.

Accordingly, one object of the present invention is to provide an exposure mask that can prevent stitch unevenness.

Another object of the present invention is to provide an exposure method using the exposure mask.

An exposure mask for realizing an object of the present invention includes a non-overlapping part including a first main pattern having a plurality of first sub-patterns having an equal interval, and disposed on one side of the non-overlapping part and having a plurality of second sub-patterns. The second main patterns may include a plurality of third sub-patterns on the other side of the first overlapping portion and the non-overlapping portion, the distance between which the second sub-patterns are constantly reduced as the distance from the first boundary that forms the non-overlapping portion. And a third overlapping portion having a third main pattern, wherein a distance between the third sub-patterns is constantly reduced as the distance from the second boundary forming the non-overlapping portion is reduced.

An exposure method for implementing another object of the present invention includes a non-overlapping portion and a non-overlapping portion including a first main pattern having a plurality of first sub-patterns having an equal interval among exposure masks, and a plurality of second sub-patterns. The non-overlapping region of the photoresist formed on the substrate and the overlapping region of the photoresist formed on the substrate through the first overlapping portion including the second main patterns and having a distance from the first boundary forming the non-overlapping portion are constantly reduced. Performing a first exposure on a portion of the exposure mask, the third main patterns disposed on the other side of the non-overlapping portion of the exposure mask and having a plurality of third sub-patterns, each of which is further away from the second boundary forming the non-overlapping portion; The second exposure is applied to the rest of the overlapping region of the photoresist formed on the substrate through the second overlapping portion where the spacing between the sub patterns is constantly reduced. And a step of performing.

Hereinafter, an exposure mask and an exposure method according to embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments, and has ordinary skill in the art. It will be apparent to those skilled in the art that the present invention may be embodied in various other forms without departing from the spirit of the invention. In the accompanying drawings, the dimensions of the non-overlapping part, the first overlapping part, the second overlapping part, and other structures are shown in an enlarged scale than actual for clarity of the present invention. In the present invention, the non-overlapping portion, the first overlapping portion, the second overlapping portion, and the alignment unit and other structures are referred to as being formed "on", "upper" or "lower", non-overlapping, first Overlap, second overlap and other structures directly formed or located above or below non-overlapping, first overlapping, second overlapping and other structures, or other non-overlapping, first overlapping, second Overlaps and other structures may be further formed on the substrate. In addition, where the first overlap, the second overlap and other structures are referred to as, for example, "first" and / or "second", etc., this is not intended to limit these members but only the first overlap. To distinguish between parts, second overlaps and other structures. Thus, for example, substrates such as “first” and / or “second” may be used selectively or interchangeably with respect to the first overlap, second overlap and other structures, respectively.

Exposure mask

5 is a plan view illustrating an exposure mask according to an exemplary embodiment of the present invention. The exposure mask according to the present embodiment is, for example, an exposure mask for forming pixel electrodes divided into a plurality in an IPS mode liquid crystal display device.

Referring to FIG. 5, the exposure mask 100 includes a non-overlapping portion 10, a first overlapping portion 20, and a second overlapping portion 30. When viewed in plan, the non-overlapping portion 10 is interposed between the first overlapping portion 20 and the second overlapping portion 30. In the present embodiment, the non-overlapping portion 10, the first overlapping portion 20 and the second overlapping portion 30 are formed on one transparent substrate.

FIG. 6 is an enlarged plan view of the first main pattern illustrated in FIG. 5.

5 and 6, the non-overlapping portion 10 includes a plurality of first main patterns 5. The non-overlapping portion 10 includes, for example, first main patterns 5 arranged in a 6 × 5 matrix form. In this embodiment, although the first main pattern 5 is arranged in the form of a 6 × 5 matrix in the non-overlapping portion 10 in FIG. 5, this is for explaining the present embodiment more easily and actually, the specific gravity is shown. In the patch 10, a myriad of first main patterns 5 are formed.

Each first main pattern 5 formed in the non-overlapping portion 10 includes a plurality of first sub patterns 7. For example, the plurality of first sub-patterns 7 included in the first main pattern 5 of the non-overlapping portion 10 may be used to form divided pixel electrodes of the IPS mode liquid crystal display.

In the present embodiment, each of the sub-patterns 7 included in each of the first main patterns 5 formed in the non-overlapping portion 10 have the same shape and are all spaced at the same interval T.

Meanwhile, the first overlapping part 20 disposed on one side of the non-overlapping part 10 includes a plurality of second main patterns 15. In the present exemplary embodiment, the plurality of second main patterns 15 included in the first overlapping part 20 are disposed every five columns, for example. In this embodiment, five columns are shown in Fig. 5 as columns I, II, III, IV and V. In FIG. In this embodiment, the number of columns may be numerous.

In this embodiment, the column I is arranged closest to the non-overlapping portion 10, and is arranged far from the non-overlapping portion 10 in the order of the II, III, IV, and V columns.

For example, up to five second main patterns 15 may be included in columns I, II, III, IV, and V, for example. In the present embodiment, the number of the second main patterns 15 included in each column may be numerous.

In the present embodiment, in order to prevent the boundary between the non-overlapping portion 10 and the first overlapping portion 20 from being recognized, the first of the non-overlapping portion 10 and the first overlapping portion 20 of the first overlapping portion 20. The further away from the boundary 11, the smaller the number of second main patterns 15 included in each column.

Specifically, as shown in the graph of FIG. 5A, four second main patterns 15 are arranged in column I, three second main patterns 15 are arranged in column II, and three second main patterns 15 are arranged in column III. Two second main patterns 15 are arranged, one second main pattern 15 is arranged in column IV, and a second main pattern 15 is not arranged in column V. FIG. In FIG. 5, reference numeral 17 will be given to an area where the second main pattern 15 is not disposed. In this embodiment, the positions of the second main patterns 15 included in the columns are randomly determined.

FIG. 7 is a plan view illustrating the second main pattern and the second sub patterns illustrated in FIG. 5.

5 and 7, the second main patterns 15 included in columns I, II, III, IV, and V, respectively, include a plurality of second subpatterns 18. For example, the plurality of second sub patterns 18 included in the second main pattern 15 of the first overlapping part 20 may be used to form divided pixel electrodes of the IPS mode liquid crystal display.

In the present exemplary embodiment, referring to the graph of FIG. 5C, the distance between the second sub patterns 18 included in the second main pattern 15 decreases gradually as the distance from the first boundary 11 increases.

Specifically, the second sub patterns 18 of the second main pattern 15 included in column I are spaced at a first interval T, and the second sub patterns 18 of the second main pattern 15 included in column II. Are spaced apart at a second interval T-1 (where T-1 < T). The second sub-patterns 18 of the second main pattern 15 included in column III are spaced apart by a third interval T-2 (where T-2 <T-1) and the second main pattern included in column IV ( The second sub-patterns 18 of 15 are spaced apart at a fourth interval T-3 (where T-3 < T-2). Finally, when the second main pattern 15 included in column V exists, the second subpatterns 18 of the second main pattern 15 may have a fourth interval T-4 (where T-4 <T-3). Are spaced apart.

As such, the number of the second main patterns 15 disposed in the first overlapping portion 20 decreases as it moves away from the first boundary 11 between the non-overlapping portion 10 and the first overlapping portion 20. It can prevent that the exposure conditions in the 1st boundary 11 part of the sticking part 10 and the 1st overlapping part 20 fluctuate greatly. In addition, the non-overlapping portion may be reduced or increased as the distance between the second sub patterns 18 included in the second main pattern 15 disposed in the first overlapping portion 20 increases away from the first boundary 11. 10) and the exposure condition at the portion of the first boundary 11 of the first overlapping portion 20 can be prevented once more.

On the other hand, the second overlapping portion 30 disposed on the other side of the non-overlapping portion 10 opposite to one side includes a plurality of third main patterns 25. In the present exemplary embodiment, the plurality of third main patterns 25 included in the second overlapping part 30 are disposed every five columns, for example. In this embodiment, five columns are shown in FIG. 5 as columns A, B, C, D, and E. FIG. In this embodiment, the number of columns may be numerous.

In this embodiment, column A is disposed closest to the non-overlapping portion 10, and is arranged far from the non-overlapping portion 10 in the order of B columns, C columns, D rows, and E columns.

On the other hand, in column A, column B, column C, column D, and column E, for example, up to five third main patterns 25 may be included. In the present embodiment, the number of the second main patterns 15 included in each column may be numerous.

In the present embodiment, in order to prevent the boundary between the non-overlapping portion 10 and the second overlapping portion 30 from being recognized, the second of the non-overlapping portion 10 and the second overlapping portion 30 of the second overlapping portion 30. The further away from the boundary 21, the smaller the number of the third main patterns 25 included in each column.

Specifically, as shown in the graph of FIG. 5B, five third main patterns 25 are arranged in column A, four third main patterns 25 are arranged in column B, and C columns are arranged in column C. Three third main patterns 25 are arranged, two third main patterns 25 are arranged in the D column, and one third main pattern 25 is arranged in the E column.

In FIG. 5, reference numeral 27 is assigned to an area where the third main pattern 25 is not disposed.

In the present exemplary embodiment, the positions of the third main patterns 25 included in the columns of the second overlapping part 30 may correspond to the second main patterns 15 included in the columns of the first overlapping part 20. Do not overlap.

FIG. 8 is a plan view illustrating the third main pattern and the third sub patterns illustrated in FIG. 5.

Referring to FIGS. 5 and 8, the third main patterns 25 included in columns A, B, C, D, and E respectively include a plurality of third sub patterns 28. For example, the plurality of third sub patterns 28 included in the third main pattern 25 of the second overlapping part 30 may be used to form divided pixel electrodes of the IPS mode liquid crystal display.

In the present embodiment, referring to the graph of FIG. 5D, the distance between the third sub patterns 28 included in the third main pattern 25 decreases gradually as the distance from the second boundary 21 increases.

In detail, the third sub patterns 28 of the third main pattern 25 included in the column A are spaced at the first interval T, and the third sub patterns 28 of the third main pattern 25 included in the column B are separated. Are spaced at a second interval T-1 (where T-1 < T). The third sub-patterns 28 of the third main pattern 25 included in column C are spaced apart by a third interval T-2 (where T-2 <T-1) and the third main pattern included in column D ( The third sub-patterns 28 of 25 are spaced apart at a fourth interval T-3 (where T-3 < T-2). Finally, when the third main pattern 25 included in the column E is present, the third sub patterns 28 of the third main pattern 25 may have a fourth interval T-4 (where T-4 <T-3). Are spaced apart.

As such, the number of the third main patterns 25 disposed in the second overlapping portion 30 decreases as the distance from the second boundary 21 between the non-overlapping portion 10 and the second overlapping portion 30 decreases. It can prevent that the exposure conditions in the part of the 2nd boundary 21 of the sticking part 10 and the 2nd overlapping part 30 fluctuate greatly.

In addition, the non-overlapping portion may be reduced or increased as the distance between the third sub patterns 28 included in the third main pattern 25 disposed in the second overlapping portion 30 increases away from the second boundary 21. 10) and the exposure condition at the portion of the second boundary 21 of the second overlapping portion 30 can be prevented once more.

Exposure method

9 is a cross-sectional view illustrating a substrate on which a first exposure process is performed on a non-overlapping region and an overlapping region by an exposure method according to an exemplary embodiment of the present invention.

5 and 9, the exposure mask 100 illustrated in FIG. 5 is accurately disposed at a designated position of the substrate 200 to which the photoresist film 210 is applied. At this time, the second overlapping portion 20 is hidden so that light does not transmit.

Subsequently, as light is scanned from the upper portion of the non-overlapping portion 10 and the first overlapping portion 20 toward the substrate 200, the non-overlapping portion 10 and the first overlapping portion 20 of the substrate 200 are exposed. Light is scanned in the non-overlapping region 201 and the overlapping region 203.

Accordingly, the first pattern 220 is formed in the non-overlapping region 201 corresponding to the non-overlapping portion 10 as the image of the first main pattern 5 and the first sub-pattern 7 described above. In addition, the second pattern 230 is formed in the overlapping region 203 corresponding to the first overlapping portion 20 as the image of the second main pattern 15 and the second subpattern 18 described above.

FIG. 10 is a cross-sectional view illustrating a substrate on which a second exposure process is performed on an overlapping area by an exposure method according to an exemplary embodiment of the present invention.

Referring to FIG. 10, about half of the overlapping region 203 of the substrate 200 is exposed and the remaining portion is not exposed. In order to expose the remaining portion of the overlapped region 203, the second overlapped portion 30 of FIG. 5 is aligned with the overlapped region 203 of the substrate 200. Since the third main pattern 25 of the second overlapping portion 30 and the second main pattern 15 of the first overlapping portion 20 do not overlap with each other, the second pattern 230 and the second overlapping portion 30 are not overlapped with each other. ), The third main pattern 25 also does not overlap.

Subsequently, light is again scanned through the third main pattern 25 of the second overlapping part 30 to the overlapping area 203 of the substrate 200, and the overlapping area 203 is described above with the third main pattern 25. The third pattern 240 is formed as shown in the image and ends the exposure of the overlapping region 203.

FIG. 11 is a graph illustrating an interval between sub-patterns included in a second pattern formed by the first overlapping part and a third pattern formed by the second overlapping part.

Referring to FIG. 11, the spacing between sub-patterns included in the second pattern 230 gradually decreases away from the boundary between the non-overlapping region 201 and the overlapping region 203 and is included in the third pattern 240. The spacing of the sub-patterns gradually increases from the boundary between the non-overlapping region 201 and the overlapping region 203.

As described in detail above, when exposing the overlapping region, the arrangement of the patterns is randomly changed to greatly reduce the exposure deviation in the overlapping region and the non-overlapping region, as well as the subpattern inside the main pattern included in the overlapping region. The spacing of these parts can also be adjusted together to further reduce the exposure variation in the overlapping and non-overlapping areas.

Although the detailed description of the present invention has been described with reference to the embodiments of the present invention, those skilled in the art or those skilled in the art will have the spirit and scope of the present invention as set forth in the claims below. It will be appreciated that various modifications and variations can be made in the present invention without departing from the scope of the art.

Claims (4)

A non-overlapping part including first main patterns; A first overlapping part adjacent to one side of the non-overlapping part and including a first pattern area including second main patterns and a first non-pattern area not including the second main patterns; And And a second overlapping portion adjacent to the other side of the non-overlapping portion and including a second pattern region including third main patterns and a second non-pattern region not including the second main patterns. A boundary that divides the non-overlapping portion and the first overlapping portion is defined as a first boundary, Define a boundary that separates the non-overlapping portion and the second overlapping portion as a second boundary, Each of the first main patterns includes a plurality of first sub patterns having equal intervals. Each of the second main patterns includes a plurality of second sub patterns spaced apart from each other. Each of the third main patterns includes a plurality of third sub patterns spaced apart from each other. The distance between the second sub-patterns decreases as the distance from the first boundary increases, The distance between the third sub-patterns decreases as the distance from the second boundary increases, The first pattern area corresponds to the second non-pattern area, and the second pattern area corresponds to the first non-pattern area. The method according to claim 1, And the number of the second main patterns disposed in the first overlapping portion decreases as the distance from the first boundary increases. The method according to claim 1, And the number of the third main patterns disposed in the second overlapping portion decreases as the distance from the second boundary increases. A non-overlapping part including first main patterns; A first overlapping part adjacent to one side of the non-overlapping part and including a first pattern area including second main patterns and a first non-pattern area not including the second main patterns; And A second overlapping portion adjacent to the other side of the non-overlapping portion and including a second pattern region including third main patterns and a second non-pattern region not including the second main patterns; Performing primary exposure on a portion of the non-overlapping region of the photoresist corresponding to the non-overlapping portion formed on the substrate and a portion of the overlapping region of the photoresist corresponding to the first overlapping portion; Performing a second exposure on a portion of the overlapping area of the photoresist, which is not exposed, corresponding to a second overlapping area of the exposure mask formed on the substrate using the exposure mask; A boundary that divides the non-overlapping portion and the first overlapping portion is defined as a first boundary, Define a boundary that separates the non-overlapping portion and the second overlapping portion as a second boundary, Each of the first main patterns includes a plurality of first sub patterns having equal intervals. Each of the second main patterns includes a plurality of second sub patterns spaced apart from each other. Each of the third main patterns includes a plurality of third sub patterns spaced apart from each other. The distance between the second sub-patterns decreases as the distance from the first boundary increases, The distance between the third sub-patterns decreases as the distance from the second boundary increases, And the first pattern region corresponds to the second non-pattern region, and the second pattern region corresponds to the first non-pattern region.

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