JP2008209636A - Exposure mask for manufacturing liquid crystal display device, and method for manufacturing liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress a longitudinal edge of the opening section of the opening section electrode from becoming arc-shaped in order to suppress the occurrence of disclination. <P>SOLUTION: An opening section electrode forming mask 110 as an exposure mask for manufacturing a liquid crystal display device has a translucent pattern 114 same as a translucent pattern 104 of a conventional opening section electrode forming mask 100 as a basic pattern part, and translucent patterns 116 and 118 for partial correction as correction pattern parts at the point where disclination may occur. That is, the opening section electrode forming mask 110 has the elongated groove-like translucent pattern 114 as a basic pattern part, and the translucent patterns 116 and 118 which expand each of the two elongated longitudinal groove-like edges as correction pattern parts. The dimensions of the correction pattern parts are smaller than the minimum dimensions of the basic pattern part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an exposure mask for manufacturing a liquid crystal display device and a method for manufacturing a liquid crystal display device, and in particular, a pair of electrodes for driving the liquid crystal molecules is provided on one of a pair of substrates opposed via liquid crystal molecules. The present invention relates to an opening electrode forming exposure mask for forming an opening in at least one of the pair of electrodes, and a method of manufacturing a liquid crystal display using the exposure mask.

  Conventionally, a TN (Twisted Nematic) method has been widely used as a display method for liquid crystal display devices, but this method has a limited viewing angle in terms of display principle. As a method for solving this, a pixel electrode and a common electrode are formed on the same substrate as a pair of electrodes for driving liquid crystal molecules, and a voltage is applied between the pixel electrode and the common electrode, so that the substrate is almost A transverse electric field method is known in which a parallel electric field is generated and liquid crystal molecules are driven in a plane parallel to the substrate surface.

  As the lateral electric field method, there are known an IPS (In Plane Switching) method and an FFS (Fringe Field Switch) method. In the IPS method, a comb-like pixel electrode and a comb-like common electrode are combined. A comb-teeth shape is one in which one end in the longitudinal direction of the opening is closed and opened at the other end as an opening for passing an electric field. When provided, each one end of each opening is connected to each other, and thus has one comb shape.

  On the other hand, in the FFS method, one of the upper electrode and the lower electrode formed via the insulating layer is assigned to the common electrode, the other is assigned to the pixel electrode, and the upper electrode is used as an opening electrode, for example, a slit shape. An opening is formed. Here, the slit shape is an elongated groove-like opening that is closed at both ends in the longitudinal direction of the opening as an opening for passing an electric field. When providing a plurality of groove-shaped openings, they are arranged separately from each other.

  Such an opening is formed by etching the electrode layer thin film. For example, when the opening has an elongated groove shape, the edge portion which is the end in the longitudinal direction is rounded and rounded. It is often a shape or an arc shape. For example, in the case of the FFS method, the electric field from the lower electrode through the opening toward the upper electrode that is the opening electrode flows along the pattern of the opening. A directional electric field will be formed. Therefore, for example, when the liquid crystal molecules are driven by applying a lateral electric field by making the initial alignment of the liquid crystal molecules substantially parallel to the long side of the opening by rubbing or the like, the initial alignment state is obtained in the linear portion of the long side of the opening. From the initial orientation state to the direction perpendicular to the arcuate shape at the edge portion of the opening.

  When the liquid crystal molecules rotate from the initial arrangement along the arcuate shape of the edge portion, the rotation direction of the liquid crystal molecules may be reversed, and the rotation direction of the liquid crystal molecules may vary depending on the location. This phenomenon in which the direction of rotation varies depending on the location is called disclination. In the boundary portion where the rotation direction is different, the liquid crystal molecules rotate in an undesired direction or cannot rotate, and thus the transmittance decreases, and the boundary line may be visually recognized. Alternatively, it is called a tilt defect, but this is sometimes simply called disclination.

  For example, Patent Document 1 discloses that in an FFS liquid crystal display device, a black matrix of an upper substrate and an edge portion of a pixel electrode of a lower substrate overlap with each other by a predetermined area, and a liquid crystal intervenes between these two substrates. Due to the electric field interference between the matrix and the pixel electrode, the twist angle of the liquid crystal molecules becomes approximately 90 degrees from the edge of the edge of the pixel electrode to the center, but the edge is arranged in the vertical direction. However, it has been pointed out that rubbing marks, that is, disclinations (inclination lines) are generated in white tone.

  Disclination will be described in more detail later, compared to the embodiment according to the present invention.

JP 2005-107535 A

  In this way, when disclination occurs, the transmittance decreases at that portion. Generally, when disclination occurs, it may be evaluated that the image quality has deteriorated. As described above, disclination is caused by the fact that the longitudinal end portion of the opening of the opening electrode has a circular arc shape in a pattern formation such as etching.

  The objective of this invention is providing the exposure mask for liquid crystal display device manufacture which can suppress that the longitudinal direction edge part of the opening part of an opening part electrode becomes circular arc shape, and the manufacturing method of a liquid crystal display device. Another object of the present invention is to provide an exposure mask for manufacturing a liquid crystal display device and a method for manufacturing the liquid crystal display device, which can manufacture a liquid crystal display device in which the occurrence of disclination is suppressed. The following means contribute to at least one of the above objects.

  An exposure mask for manufacturing a liquid crystal display device according to the present invention is used for manufacturing a liquid crystal display device in which a pair of electrodes for driving the liquid crystal molecules is provided on one of a pair of substrates facing each other through liquid crystal molecules, An opening electrode forming exposure mask for forming an opening in at least one side electrode of the pair of electrodes and using the opening as an opening electrode, the transparent electrode corresponding to the shape of the opening of the opening electrode A basic pattern portion having a light pattern or a non-light-transmitting pattern, and a portion that expands or contracts the light-transmitting pattern or the non-light-transmitting pattern of the basic pattern portion corresponding to a portion of a longitudinal end portion of the shape of the opening. And a correction pattern portion which is a correction pattern.

  With the above configuration, the exposure mask for manufacturing a liquid crystal display device is longer in the shape of an opening that tends to be an arc shape in an etching process or the like than a basic pattern having a pattern corresponding to the shape of the opening in the design of the liquid crystal display. A correction pattern portion, which is a partial correction pattern, is provided at the end portion in the direction, and the light-transmitting pattern or the non-light-transmitting pattern of the basic pattern portion is expanded or reduced. Thereby, in the opening electrode forming step, it is possible to suppress the end portion in the longitudinal direction of the opening from becoming an arc shape, and it is possible to manufacture a liquid crystal display device in which disclination is suppressed.

  Further, in the exposure mask for manufacturing a liquid crystal display device according to the present invention, the shape of the opening is a slit-type shape in which a plurality of elongated groove-like openings each closed at both ends in the longitudinal direction are arranged separately. And the correction pattern portion is a partial correction pattern that extends the light-transmitting pattern or the non-light-transmitting pattern of the basic pattern portion in correspondence with the respective portions at both ends in the longitudinal direction of the slit shape. Is preferred.

  In the case of a slit-shaped opening, the end of the elongated groove-shaped opening is likely to have an arc shape in an etching process or the like, so the basic pattern portion is expanded in the exposure mask to enlarge the end of the elongated groove-shaped opening. And Thereby, in the opening electrode forming step, it is possible to suppress the end portion in the longitudinal direction of the opening from becoming an arc shape, and it is possible to manufacture a liquid crystal display device in which disclination is suppressed.

  Further, in the exposure mask for manufacturing a liquid crystal display device according to the present invention, the shape of the opening is a comb-like shape in which one end in the longitudinal direction is closed and the other end is open, The correction pattern portion extends the light-transmitting pattern or the non-light-transmitting pattern of the basic pattern portion corresponding to the portion of the one side end portion, and corresponds to the portion of the basic pattern portion corresponding to the portion of the other side end portion. A partial correction pattern that reduces the light-transmitting pattern or the non-light-transmitting pattern is preferable.

  In the case of the comb-shaped opening, the opening pattern is open at one end of the longitudinal end, whereas the pattern is closed at the other end. Therefore, the light-transmitting pattern or non-light-transmitting pattern of the basic pattern portion is expanded for the other side end portion where the opening is closed, and the light-transmitting pattern or basic pattern portion of the one side end portion where the opening portion is open. Reduce the non-light-transmitting pattern. Thereby, in the opening electrode forming step, it is possible to suppress the end portion in the longitudinal direction of the opening from becoming an arc shape, and it is possible to manufacture a liquid crystal display device in which disclination is suppressed.

  In the exposure mask for manufacturing a liquid crystal display device according to the present invention, when the opening has a slit shape, the correction pattern portion has a rubbing direction in which the extending direction of the longitudinal end portion initially aligns the liquid crystal molecules. When the inclination angle is a positive angle, the longitudinal direction corresponding to the circular second quadrant portion and the fourth quadrant portion with the longitudinal direction extending as the X axis and the vertical direction as the Y axis When the end portion is provided with a partial correction pattern for extending a translucent pattern or a non-translucent pattern, and the tilt angle is a negative angle, it corresponds to at least the first quadrant portion or the third quadrant portion of the circle. It is preferable that a partial correction pattern for extending a translucent pattern or a non-translucent pattern is provided at the end in the longitudinal direction.

  In the exposure mask for manufacturing a liquid crystal display device according to the present invention, when the opening has a slit shape, the correction pattern portion has a rubbing direction in which the extending direction of the longitudinal end portion initially aligns the liquid crystal molecules. When the inclination angle is a positive direction angle, the translucent pattern is formed at the end in the longitudinal direction corresponding to the circular fourth quadrant with the extending direction in the longitudinal direction as the X axis and the vertical direction as the Y axis. Alternatively, when a partial correction pattern for reducing the non-light-transmitting pattern is provided and the inclination angle is an angle in the negative direction, the light-transmitting pattern or the non-light-transmitting pattern is formed at the end in the longitudinal direction corresponding to the first quadrant of the circle. It is preferable that a partial correction pattern for reducing the light transmission pattern is provided.

  The disclination appears in the lower right corner and the upper left corner or the upper right corner and the lower left corner of the end portion in the longitudinal direction because of the relationship between the longitudinal direction of the opening and the rubbing direction. With the above configuration, the partial correction pattern is provided in the portion where the disclination may appear, so that the portion can be prevented from having an arc shape, and the liquid crystal display device in which the disclination is suppressed can be manufactured.

  In the exposure mask for manufacturing a liquid crystal display device according to the present invention, it is preferable that the correction pattern portion has a pattern size smaller than a minimum pattern size of the basic pattern portion. For example, by using the optical proximity effect, the basic pattern portion can have a pattern dimension that can be processed at the resolution of the exposure apparatus, and the correction pattern can have a pattern dimension that is less than or equal to the resolution of the exposure apparatus. Thereby, the fine adjustment of the shape with the dimension below the resolution of an exposure apparatus is attained about the longitudinal direction edge part of an opening part.

  In addition, the method for manufacturing a liquid crystal display device according to the present invention includes forming an opening in at least one side electrode of a pair of electrodes for driving liquid crystal molecules using the exposure mask for manufacturing a liquid crystal display device, and forming the opening electrode. It is characterized by forming. This suppresses the occurrence of disclination in the liquid crystal display device.

  Embodiments according to the present invention will be described below in detail with reference to the drawings. Hereinafter, the FFS method will be described as a configuration in which a pair of electrodes for driving liquid crystal molecules is provided on one of a pair of substrates facing each other with liquid crystal molecules interposed therebetween. That is, an upper electrode and a lower electrode are provided on an element side substrate via an insulating layer, and the upper electrode is described as an opening electrode. Here, the lower electrode will be described as a pixel electrode, and the upper electrode as an opening electrode will be described as a common electrode, but this is the reverse configuration, that is, the lower electrode as a common electrode and the upper electrode as an opening electrode as a pixel electrode. Also good.

  Further, as described below, the shape of the opening may be a slit shape or a comb shape. In addition to the FFS configuration, an IPS configuration may be used.

  In the following FFS method, the common electrode is arranged separately for each pixel. However, the common electrode may not be divided for each pixel.

  In the following description, in the opening electrode portion formation mask, the light-transmitting pattern portion corresponds to the opening portion, but the non-light-transmitting pattern portion may correspond to the opening portion.

  Embodiments of the present invention relate to an exposure mask for forming an opening electrode of a liquid crystal display device, and provide an exposure mask capable of suppressing disclination in a liquid crystal display device of a lateral electric field drive system. Therefore, prior to the description of the configuration of the exposure mask, the mechanism that causes disclination in the lateral electric field driving method, including the configuration of the liquid crystal display device, will be described with reference to FIGS. Since FIGS. 1 to 4 illustrate an example in which disclination occurs, the opening electrode formation exposure mask is assumed to be general, and the opening electrode formation according to the embodiment of the present invention is performed. An exposure mask is not used.

  FIG. 1 is a cross-sectional view of a portion of one subpixel in an FFS color liquid crystal display device. FIG. 2 is a plan view corresponding to the cross-sectional view of FIG. 1 and shows three sub-pixels corresponding to one pixel. FIG. 3 is a diagram illustrating a state of an electric field E that drives liquid crystal molecules in the FFS method. FIG. 4 is a diagram for explaining how disclination occurs.

  FIG. 1 is a cross-sectional view of the liquid crystal display device 10 as described above, and shows a portion of one subpixel. Here, for example, when color display is performed with R, G, and B, the sub-pixels are display portions corresponding to R, G, and B. In this example, the sub-pixels of R, One sub-pixel and B sub-pixel are used as one unit. Note that the sub-pixel may be referred to as a sub-pixel, and in that case, the one pixel is referred to as one pixel. As shown in FIG. 1, the liquid crystal display device 10 includes an element side substrate 20, a counter side substrate 60, and liquid crystal molecules 50 sandwiched between the element side substrate 20 and the counter side substrate 60. .

  The counter substrate 60 is the side facing the user in the liquid crystal display device 10. The counter substrate 60 is configured by stacking several films. In the example of FIG. 1, a glass substrate 62, a black matrix 64, and a color filter 66 are configured from the side facing the opposing user toward the element side substrate 20. In the cross-sectional view of FIG. 1, the black matrix 64 is indicated by a broken line because it is hidden behind the color filter 66 or disposed below it. Since these materials, dimensions, forming methods, and the like can be used as a general method for manufacturing an active matrix liquid crystal display device, detailed description thereof is omitted.

  The element-side substrate 20 is also referred to as a TFT substrate or a TFT-side substrate, and is a substrate on the side where the TFT element that is the switching element 80 is disposed, and is a substrate for the counter-side substrate 60. Here, it is also a substrate on which a pair of electrodes for driving the liquid crystal molecules 50 is disposed. On the element side substrate 20, a plurality of films patterned in a multilayer structure by a known film forming technique and a pattern forming technique are laminated.

  In the example of FIG. 1, from the side not facing the user toward the liquid crystal molecule 50 side, the glass substrate 22, the semiconductor layer 24, the gate insulating film 26, the gate electrode 28 formed in the same process, and the common electrode wiring 29 The interlayer insulating film 30, the source / drain wirings 32 and 33 formed in the same process, the common electrode connecting portion 34, the insulating film 36, the pixel electrode 38, the FFS insulating film 40, and the common electrode 42 are sequentially formed. Since these materials, dimensions, forming methods, and the like can be used as a general method for manufacturing an active matrix liquid crystal display device, detailed description thereof is omitted.

  Although not shown in FIG. 1, an alignment film is provided on the common electrode 42. An alignment film is similarly provided on the surface of the counter substrate 60 facing the liquid crystal molecules 50.

  FIG. 2 is a plan view corresponding to the cross-sectional view of FIG. Here, one pixel composed of three sub-pixels is shown. 1 corresponds to a cross-sectional view along the line AA shown in FIG. Elements similar to those in FIG. 1 are denoted by the same reference numerals.

  In each sub-pixel, a gate line that partially becomes the gate electrode 28 and the data line 35 are wired so as to be orthogonal to each other, and a TFT element that is a switching element 80 is disposed at the intersection. The gate line becomes the gate electrode 28 shown in FIG. 1 at the switching element 80, and the data line 35 is connected to the source / drain wiring 32 shown in FIG. As described above, the liquid crystal display device 10 is a so-called active matrix display device in which the TFT elements as the switching elements 80 are arranged at the intersections of the plurality of gate lines and the plurality of data lines 35. Note that the gate line is also called a scan line, a scan line, or a scan signal line, and the data line 35 is also called a signal line, a signal line, a video signal line, a video signal line, or the like.

  The TFT element as the switching element 80 is connected to the gate insulating film 26 formed on the semiconductor layer 24 shown in FIG. 1, the gate electrode 28 provided on the gate insulating film 26, and the source / drain wirings 32 and 33. This is a transistor element composed of a source and a drain. Note that TFT is an abbreviation for Thin Film Transistor. One of the source and drain of the TFT element which is the switching element 80 is connected to the data line 35, for example, the drain, and the other is connected to the pixel electrode 38, for example. Since the drain and the source are compatible, the source may be connected to the data line 35 and the drain may be connected to the pixel electrode 38. The TFT element which is the switching element 80 conducts between the drain and the source by selecting the gate line, and the video signal from the data line 35 connected to the drain in the above example is supplied to the pixel electrode 38.

  Here, the pixel electrode 38 is indicated by an alternate long and short dash line in FIG. 2, and is disposed in a region surrounded by the data line 35 and the common electrode wiring 29. Further, the common electrode 42 is indicated by a thick solid line in FIG. 2, and is disposed in the entire subpixel area excluding the data line 35. In the example of FIG. 2, the common electrode 42 is shown to be formed separately for each sub-pixel. However, depending on the case, the common electrode 42 may be formed across each sub-pixel.

  A slit 43 is formed in the common electrode 42. As shown in FIG. 1, the slit 43 applies a voltage between the common electrode 42 that is the upper electrode and the pixel electrode 38 that is the lower electrode formed through the FFS insulating film 40, and the liquid crystal is generated by the electric field. It is an opening for driving molecules. In FIG. 2, a plurality of slits 43 are provided in the common electrode 42, and each slit 43 is arranged with the longitudinal direction of the opening being parallel to each other and separated from each other. Since the slit 43 is a long and narrow groove-shaped opening whose both ends in the longitudinal direction are closed, the end in the longitudinal direction is rounded during the etching process. Hereinafter, this rounded end portion is referred to as an edge portion. Disclination occurs at this edge portion.

  FIG. 3 is a diagram schematically illustrating the state of the electric field E applied between the common electrode 42 and the pixel electrode 38. Here, an electric field E that passes through the slit 43 provided in the common electrode 42 and goes to the pixel electrode 38 through the FFS insulating film 40 is shown. The direction of the electric field may be reversed, that is, from the pixel electrode 38 to the common electrode 42 through the slit 43.

  FIG. 4 is an enlarged view of a portion B in FIG. 2, and is a diagram schematically illustrating how a so-called disclination occurs in an edge portion that is an end portion of the slit 43. Here, the slit 43 is shown as being parallel to the left-right direction of the paper surface, and the rubbing direction R-R is inclined slightly upward to the left-right direction of the paper surface. The tilt angle can be several degrees, such as an angle between 3 degrees and 5 degrees, for example. That is, in a state where no electric field is applied, the liquid crystal molecules L are inclined slightly upward to the slit 43. Note that this rubbing direction is an example for explanation, and therefore a different direction or a different tilt angle may be used.

  Since the slit 43 is opened in the transparent conductive material film constituting the common electrode 42 by, for example, an etching technique, the edge portion is somewhat rounded as described above, as shown in FIG. It becomes an arc shape close to a semicircular shape.

  When the electric field E is not applied, the liquid crystal molecules L at the edge portion of the slit 43 are in the initial arrangement state and aligned in the rubbing direction. That is, it is slightly inclined from the edge of the slit 43, but is aligned in a substantially parallel direction. When the electric field E is applied here, the electric field E rotates in the direction of the electric field E until it is substantially perpendicular to the edge of the slit 43. Also in this arc-shaped portion, since the electric field is applied orthogonally to the edge of the slit 43, the direction of the electric field is 180 degrees along the arc shape because the arc shape rotates half way along the edge of the slit 43. ° will change. For example, when an electric field is applied to the slit 43 shown at the upper left in FIG. 4, the liquid crystal molecules L rotate counterclockwise in the long side portion on the upper side of the slit 43, and similarly the long side on the lower side of the slit 43. Even in the portion, the liquid crystal molecules L rotate counterclockwise. However, in the semicircular arc-shaped portion, the liquid crystal molecules L rotate counterclockwise in the upper quadrant arc-shaped portion, whereas in the lower quadrant arc shape, the liquid crystal molecules L Will rotate clockwise.

  In this way, when an electric field is applied to rotate the liquid crystal molecules L in a desired direction, at the right edge portion of the slit 43, the lower right quarter-circular arc-shaped portion is opposite to the desired direction. It occurs that the liquid crystal molecules L rotate. That is, it does not rotate in the desired direction. Thus, when a lateral electric field is applied, the rotation direction of the liquid crystal molecules L varies depending on the location at the edge portion. A phenomenon in which the rotation direction varies depending on the location is disclination. At the boundary portions where the rotation directions are different, the liquid crystal molecules L rotate or cannot rotate in an undesired direction, so that the transmittance decreases and the boundary lines may be recognized visually. Or, it is called a tilt defect, or simply this is called disclination. In FIG. 4, an area where disclination occurs is indicated by D.

  In FIG. 4, the region D is an edge portion of the edge of the slit 43 when viewed. More specifically, the normal direction of the slit 43 is in a range from the point where it coincides with the initial alignment direction of the liquid crystal molecules L, that is, the rubbing direction RR, to the point where it forms an angle of 90 ° in the clockwise direction. In this range of FIG. 4, when an electric field is applied, the liquid crystal molecules L rotate clockwise and become orthogonal to the edge of the edge portion. In other regions, the liquid crystal molecules L are counterclockwise. Rotate in the direction perpendicular to the edge of the slit 43. In other words, the region D where the disclination of the edge portion of the slit 43 occurs has an angle of 90 ° further clockwise from the point where the normal direction of the edge portion of the slit 43 coincides with the rubbing direction RR. This is the range up to the point.

  In other words, as shown in FIG. 4, when the end of the opening has an arc shape like the slit 43, the region D where the disclination occurs is an angular relationship as shown in FIG. When the inclination angle formed by the extending direction of the longitudinal end of 43 with the rubbing direction RR is a positive direction, that is, an angle in the counterclockwise direction, the extending direction of the slit 43 in the longitudinal direction is defined as the X axis and the vertical direction thereof. These are the second quadrant part and the fourth quadrant part when counting in a counterclockwise direction with respect to a circle whose axis is Y. In addition, when the inclination angle is a negative direction, that is, an angle in the clockwise direction, the first quadrant portion and the third quadrant portion are circular.

  Unlike FIG. 4, even when the common electrode has a comb-like shape and the tip portion of the transparent conductive material portion has an arc shape, the normal direction of the arc-shaped edge portion is the rubbing direction R. Disclination occurs in the range from the point where it coincides with −R to the point where it forms an angle of 90 ° clockwise. Therefore, in this case, the disclination region D has an inclination angle that the direction in which the end portion of the transparent conductive material extends in the longitudinal direction and the rubbing direction RR is a positive direction, that is, an angle that is counterclockwise. In some cases, it is the fourth quadrant that is counted by turning counterclockwise about a circle with the longitudinal direction of the transparent conductive material as the X axis and the vertical direction as the Y axis. Further, when the inclination angle is a negative direction, that is, an angle in the clockwise direction, this is the circular first quadrant portion. If this is described in a circular shape with respect to the comb-shaped opening, the disclination-generating region has a positive inclination angle formed by the extending direction of the longitudinal end of the opening with the rubbing direction RR, That is, when the angle is counterclockwise, it is the second quadrant that is counted by turning counterclockwise about a circle with the longitudinal direction of the opening as the X axis and the vertical direction as the Y axis. Further, when the inclination angle is a negative direction, that is, an angle in the clockwise direction, this is the circular third quadrant portion.

  Next, the opening electrode formation mask according to the embodiment of the present invention will be described. The opening electrode mask is an exposure mask for forming the slits 43 in the common electrode 42 described in FIG. This exposure mask is used to form the common electrode 42 on the FFS insulating film 40 described with reference to FIG. 1 in a predetermined shape by, for example, a wet etching technique. In the above example, the predetermined shape is a shape in which a plurality of slits are opened in a rectangular shape for each sub-pixel. That is, the transparent electrode material film for the common electrode formed on the entire surface of the element side substrate is formed in a rectangular shape for each sub-pixel, and an opening electrode formation mask is provided to open a plurality of slits in the rectangular shape. Is used.

  As an example of an actual process, the following procedure can be taken. That is, after the film forming process of the FFS insulating film 40, a film forming process of the transparent conductive material film constituting the common electrode 42 is performed, and a resist process of covering the photosensitive photoresist with, for example, coating is performed thereon. Then, an exposure step using the opening electrode formation mask is performed. Subsequent to the exposure step, a photosensitive resist development step is performed. Here, the photosensitive resist is formed into a pattern having a shape corresponding to the shape of the common electrode 42. And the etching process of the transparent conductive material film for common electrodes is performed using this photosensitive resist as an etching mask. Thus, the common electrode transparent conductive material film is formed in the shape of the predetermined common electrode 42. Thereafter, the used photosensitive resist is peeled off.

  An example of the opening electrode formation mask will be described with reference to FIGS. FIG. 5 shows an opening electrode formation mask 110 when forming a slit-shaped opening, and FIG. 6 shows an opening electrode forming mask 130 when forming a comb-shaped opening. 7 and 8 are diagrams showing the state of the correction pattern portion described later in the opening portion electrode formation mask.

  Here, for comparison, the opening electrode forming masks 100 and 120 of the prior art are also shown. The opening electrode formation masks 110 and 130 have a sufficiently large area so that, for example, the entire area of the element side substrate of the liquid crystal display device can be collectively exposed. 5 and 6 show a portion corresponding to one sub-pixel. For ease of explanation, the shape and dimensions of the opening are simplified.

  FIG. 5 is a diagram showing a state of one sub-pixel of the opening electrode formation mask 110 for forming the slit-shaped opening as described above. Here, the slit shape is a shape of the opening that is formed by separating a plurality of elongated groove-like openings that are closed at both ends in the longitudinal direction.

  5A, the non-transparent pattern 102 has a rectangular shape corresponding to one sub-pixel, and the translucent pattern 104 is formed in an elongated groove shape. A plurality of the longitudinal directions are provided parallel to each other. When exposure is performed using the opening electrode formation mask 100, light passes through the portion of the translucent pattern 104 and the photosensitive resist is exposed to the shape of the translucent pattern 104. Since the characteristics of the photosensitive resist change when exposed to light, the exposed portion can be removed by using an appropriate developer, whereby the photosensitive resist has the same shape as the translucent pattern 104. It is formed. That is, an opening is formed in the photosensitive resist in the same shape as the translucent pattern 104. The common electrode is formed in a shape corresponding to the opening of the photosensitive resist by etching the transparent conductive material film for the common electrode using the photosensitive resist having the opening formed in this manner.

  Thus, in the example of FIG. 5, the translucent pattern 104 has the shape of the opening of the common electrode. Of course, the shape of the opening of the common electrode can be changed to a non-light-transmitting pattern by changing the type of resist.

  When the opening electrode forming mask 100 according to the prior art is used, as described above, in the elongated groove shape of the opening, the edge portion which is the end in the longitudinal direction is rounded and round or arc-shaped. Become. This arcuate shape causes disclination.

  In the opening electrode forming mask 110 according to the embodiment, the light transmitting pattern 114 that is the same as the light transmitting pattern 104 of the opening electrode forming mask 100 according to the prior art is used as a basic pattern portion, and further corrected to a location where disclination occurs. It has translucent patterns 116 and 118 for partial correction, which are pattern portions. That is, as the translucent pattern, translucent patterns 116 and 118 that extend the elongated groove-shaped translucent pattern 114 as the basic pattern portion and the respective longitudinal end portions of the elongated groove-shaped portion as the correction pattern portion. And have.

  The translucent patterns 116 and 118 as correction pattern portions are provided in the portions where disclination occurs. That is, as described above, when the inclination angle formed by the extending direction of the end of the opening in the longitudinal direction and the rubbing direction is a positive angle, the extending direction of the opening in the longitudinal direction is the X axis and the vertical direction is When the Y-axis is a circular second quadrant portion and the fourth quadrant portion, and when the tilt angle is a negative angle, the circular first quadrant portion and the third quadrant portion are transparent as a correction pattern portion. Light patterns 116 and 118 are provided.

  FIG. 7 is a detailed view of a portion of the translucent pattern 116 as a correction pattern. Note that the other light-transmitting pattern 118 portion of the correction pattern portion has the same content, and therefore, here, the light-transmitting pattern 116 portion will be described as a representative. In FIG. 7, the non-light-transmitting pattern 102 is indicated by hatching, and the portions not hatched are the light-transmitting patterns 114 and 116.

  As shown in FIG. 7, the translucent pattern 116 as the correction pattern portion is provided so as to expand the lower right corner of the translucent pattern 114 as the basic pattern portion. This lower right corner corresponds to the circular fourth quadrant portion described above, and the inclination angle formed by the extending direction of the longitudinal end portion of the translucent pattern 114 as the basic pattern portion with the rubbing direction is a positive angle. It is. When the inclination angle formed by the extending direction of the end portion in the longitudinal direction of the translucent pattern 114 and the rubbing direction is a negative angle, the translucent pattern 116 as the correction pattern unit is the same as the translucent pattern 114 as the basic pattern unit. It is provided so as to expand the upper right corner, that is, the above-mentioned circular first quadrant.

  The translucent pattern 116 as the correction pattern portion is provided so as to be expanded in a square shape at the lower right corner of the translucent pattern 114 of the basic pattern portion. The square shape has an inclination of the center line of about 45 degrees with respect to the longitudinal direction of the translucent pattern 114, and the width dimension B and the longitudinal extension dimension C along the center line are both transparent of the basic pattern portion. It is smaller than the width dimension A of the optical pattern 114.

  As an example of dimensions, when the width S of the slit of the common electrode formed after etching is about 4.0 μm, the width dimension A of the translucent pattern 114 can be about 3.4 μm. The extension dimension C of the translucent pattern 116 as the correction pattern portion can be about 1.75 μm and the width dimension B can be about 1.4 μm.

  In a high-definition liquid crystal display device, the width dimension A of the light-transmitting pattern 114 in the basic pattern portion is often set to a minimum dimension near the resolution limit of the exposure apparatus. Therefore, normally, even if the minimum dimension of the pattern of the opening electrode formation mask is smaller than the resolution of the exposure apparatus, it cannot be exposed to a desired dimension and shape. Here, by utilizing the optical proximity effect, it is possible to obtain a fine pattern having a resolution lower than that of the exposure apparatus. This is to correct the shape of the peripheral portion of the basic pattern portion by providing a correction pattern portion having a shape and dimensions in consideration of light diffraction etc. in the peripheral portion of the basic pattern portion near the resolution limit of the exposure apparatus, This is based on the ability to form a pattern with an accuracy higher than the resolution of the exposure apparatus. In the example of FIG. 7, with only the light-transmitting pattern 114 that is the basic pattern portion, the exposure pattern has an arc shape at the end in the longitudinal direction due to the limit of the resolution of the exposure apparatus. By providing the light pattern 116, the arc shape can be corrected to obtain an exposure pattern substantially close to a rectangle.

  Therefore, in order to use the optical proximity effect, the dimension of the translucent pattern 116 that is the correction pattern portion is set smaller than the minimum dimension of the translucent pattern 114 that is the basic pattern portion. In the above example, if the resolution of the exposure apparatus is about 3 μm, the minimum dimension of the translucent pattern 114 as the basic pattern portion is set to about 3.4 μm, which is larger than the resolution of about 3 μm of the exposure apparatus, The minimum dimension of the translucent pattern 116 can be about 1.4 μm, which is smaller than the resolution of the exposure apparatus of about 3 μm.

  In such an opening electrode forming mask, in accordance with a general exposure mask manufacturing method, the minimum dimension of the light-transmitting pattern 114 as the basic pattern portion is set within the allowable range of the resolution of the exposure apparatus, and the longitudinal direction of the light-transmitting pattern 114 is A light-transmitting pattern formed so as to provide a light-transmitting pattern 116 which is a correction pattern portion having a small dimension exceeding the resolution of the exposure apparatus at the end can be used.

  Here, returning to FIG. 6, FIG. 6 is a diagram showing a state of one sub-pixel of the opening electrode formation mask 130 for forming the comb-shaped opening as described above. Here, the comb-teeth shape is a shape of the opening, in which one end portion in the longitudinal direction is closed and the other end portion is open, and the open portion becomes an opening portion. When the openings are arranged so that the longitudinal directions thereof are parallel to each other, the respective one side ends are closed, so that the shape of the portion that is not the opening is a comb-like shape connected at one end.

  FIG. 6A shows an opening electrode forming mask 120 having a comb-like shape according to the prior art shown for comparison. Here, it is shown that the non-light-transmitting pattern 122 has a comb-tooth shape. Here, the opening is indicated by a translucent pattern 124, the other end 126 in the longitudinal direction is open, and the one end 128 is closed. Speaking of the non-light-transmitting pattern 122, an elongated arm pattern having substantially the same shape as that of the light-transmitting pattern 124 is connected at a position corresponding to the one side end portion 128. This elongated arm portion pattern portion may be generally called a line with the opening as a space when compared with the opening.

  Thus, in the example of FIG. 6, the translucent pattern 124 has the shape of the opening of the common electrode. Of course, the shape of the opening of the common electrode can be changed to a non-light-transmitting pattern by changing the type of resist.

  Using the prior art opening electrode forming mask 120, as described above, in the elongated groove shape of the opening, the edge portion which is the end in the longitudinal direction is rounded or rounded or arcuate. Become. Specifically, the one end portion 128 of the translucent pattern 124 has a round shape or an arc shape. Further, an edge portion which is an end portion in the longitudinal direction of the elongated arm portion of the non-light-transmitting pattern 122 is rounded to have a round shape or an arc shape. The rounded portion of the non-light-transmitting pattern 122 is a portion corresponding to the other end 126 of the light-transmitting pattern 124. These arcuate shapes cause disclination.

  The opening electrode formation mask 130 according to the embodiment uses the same light transmission pattern 134 as the light transmission pattern 124 of the opening electrode formation mask 120 of the prior art as a basic pattern portion, and further, a correction pattern at a location where disclination occurs. Part. That is, as the translucent pattern, an elongated groove-shaped translucent pattern 134 as a basic pattern portion, and as a correction pattern portion, a partial correction pattern that extends a portion of one end portion 138 in the longitudinal direction of the elongated groove shape. 142 and a partial correction pattern 140 for reducing the other end portion 136. From the viewpoint of the non-light-transmitting pattern 132, the partial correction pattern 140 extends the non-light-transmitting pattern 132 that is the basic pattern portion. As described above, the correction pattern portion is provided to expand or reduce the opening of the basic pattern portion so that disclination does not occur.

  The partial correction patterns 140 and 142 serving as correction pattern portions are provided in a portion where disclination occurs. That is, as described above, when the inclination angle formed by the extending direction of the end portion in the longitudinal direction of the translucent pattern 134 with the rubbing direction is a positive angle, the extending direction in the longitudinal direction of the translucent pattern 134 that is the opening portion. As a correction pattern portion in a circular second quadrant portion with the X axis as the X axis and the vertical direction as the Y axis, and when the tilt angle is a negative direction angle, A partial correction pattern 142 that extends 134 is provided.

  On the other hand, with respect to the non-transparent pattern 132, at the end of the elongated arm portion extending in the longitudinal direction, when the tilt angle is a positive angle, the tilt angle is a negative angle in the circular fourth quadrant. In some cases, a partial correction pattern 140 that extends the non-translucent pattern 132 is provided in a circular first quadrant.

  As described above, in the case of the comb-shaped opening, as the correction pattern portion, the partial correction pattern 142 that expands the translucent pattern 134 and the non-transparent pattern 132 are expanded by reducing the translucent pattern 134. The partial correction pattern 140 is provided. Details of the former shape are the same as those described with reference to FIG. 7, but the latter shape corresponds to expansion of the non-light-transmitting pattern 132, and therefore differs from FIG. 7.

  FIG. 8 is a detailed view of a portion of the partial correction pattern 140 as a correction pattern. In FIG. 8, the non-light-transmitting pattern 132 is indicated by hatching, and the portion not hatched is the light-transmitting pattern 134.

  As shown in FIG. 8, the partial correction pattern 140 as the correction pattern portion is provided so as to extend the lower right corner of the non-light-transmitting pattern 132 as the basic pattern portion. This lower right corner corresponds to the circular fourth quadrant portion described above, and the inclination angle formed by the extending direction of the longitudinal end portion of the non-light-transmitting pattern 132 as the basic pattern portion with the rubbing direction is an angle in the positive direction. Is the case. When the inclination angle formed by the extending direction of the end portion in the longitudinal direction of the non-light-transmitting pattern 132 with the rubbing direction is a negative angle, the partial correction pattern 140 as the correction pattern portion is not light-transmitting as the basic pattern portion. The pattern 132 is provided so as to expand the upper right corner of the pattern 132, that is, the first quadrant of the circle.

  The partial correction pattern 140 as the correction pattern portion is provided so as to be expanded in a square shape at the lower right corner of the non-light-transmitting pattern 132 of the basic pattern portion. The square shape is such that the inclination of the center line is about 45 degrees with respect to the longitudinal direction of the non-transparent pattern 132, and the width dimension I and the longitudinal extension dimension J along the center line are both of the basic pattern portion. The width dimension H of the non-light-transmitting pattern 132 is smaller.

  As an example of the dimension, when the width of the elongated arm portion of the common electrode formed after etching, that is, the width dimension W of the line is about 3.0 μm, the width dimension H of the non-transparent pattern 132 is about 3. In this case, the extension dimension J of the partial correction pattern 140 as the correction pattern portion can be about 1.5 μm, and the width dimension I can be about 1.4 μm.

  As described with reference to FIG. 7, by using the optical proximity effect, it is possible to obtain a fine pattern below the resolution of the exposure apparatus. In the example of FIG. Alternatively, with only the non-light-transmitting pattern 132, the exposure pattern has an arc shape at the end portion in the longitudinal direction due to the limit of the resolution of the exposure apparatus, but by providing a fine partial correction pattern 140 that is a correction pattern portion, By correcting the arc shape, it is possible to obtain an exposure pattern substantially close to a rectangle.

  Therefore, in order to use the optical proximity effect, the size of the partial correction pattern 140 that is the correction pattern portion is set smaller than the minimum size of the light-transmitting pattern 134 or the non-light-transmitting pattern 132 that is the basic pattern portion. In the above example, if the resolution of the exposure apparatus is about 3 μm, the minimum dimension of the non-transparent pattern 132 that is the basic pattern portion is about 3.6 μm, which is larger than about 3 μm of the resolution of the exposure apparatus, and the correction pattern portion The minimum dimension of the partial correction pattern 140 can be about 1.4 μm, which is smaller than the resolution of the exposure apparatus of about 3 μm.

  As described with reference to FIGS. 5 and 7, such an opening electrode forming mask has a basic pattern portion having a minimum dimension of the basic pattern portion within an allowable range of the resolution of the exposure apparatus in accordance with a general exposure mask manufacturing method. The correction pattern portion having a small dimension exceeding the resolution of the exposure apparatus can be used at the end in the longitudinal direction.

It is sectional drawing of the liquid crystal display device for demonstrating disclination. FIG. 2 is a plan view corresponding to FIG. 1. It is a figure explaining the mode of the electric field formed between a common electrode and a pixel electrode. It is a figure explaining a mode that disclination generate | occur | produces in the edge part of a slit. In embodiment which concerns on this invention, it is a figure which shows the mode of an opening part electrode formation mask when opening part shape is a slit shape. In embodiment which concerns on this invention, it is a figure which shows the mode of an opening part electrode formation mask when opening part shape is a comb-tooth shape. In the embodiment according to the present invention, it is a diagram for explaining the details of the partial correction pattern. In the embodiment according to the present invention, it is a diagram for explaining the details of another partial correction pattern.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Liquid crystal display device, 20 Element side substrate, 22, 62 Glass substrate, 24 Semiconductor layer, 26 Gate insulating film, 28 Gate electrode, 29 Common electrode wiring, 30 Interlayer insulating film, 32, 33 Source / drain wiring, 34 Common electrode Connection part, 35 data line, 36 insulating film, 38 pixel electrode, 40 FFS insulating film, 42 common electrode, 43 slit, 50 liquid crystal molecule, 60 opposite substrate, 64 black matrix, 66 color filter, 80 switching element, 100, 110, 120, 130 Opening electrode formation mask, 102, 122, 132 Non-transparent pattern, 104, 114, 116, 118, 124, 134 Translucent pattern, 126, 136 The other end, 128, 138 One end Part, 140, 142 Partial correction pattern.

Claims (7)

Used for manufacturing a liquid crystal display device in which a pair of electrodes for driving the liquid crystal molecules is provided on one of a pair of substrates opposed via liquid crystal molecules, and at least one side electrode of the pair of electrodes has an opening. Is an opening electrode forming exposure mask for forming an opening electrode,
A basic pattern portion having a light-transmitting pattern or a non-light-transmitting pattern corresponding to the shape of the opening of the opening electrode;
A correction pattern portion that is a partial correction pattern that expands or reduces the light-transmitting pattern or the non-light-transmitting pattern of the basic pattern portion in correspondence with the longitudinal end portion of the shape of the opening,
An exposure mask for manufacturing a liquid crystal display device, comprising: The exposure mask for manufacturing a liquid crystal display device according to claim 1,
The shape of the opening is a slit-type shape in which a plurality of elongated groove-like openings that are closed at both ends in the longitudinal direction are arranged separately,
The correction pattern portion is
A liquid crystal display device manufacturing method comprising: a partial correction pattern for extending a light transmitting pattern or a non-light transmitting pattern of the basic pattern portion corresponding to each portion of both ends in the longitudinal direction of the slit shape Exposure mask. The exposure mask for manufacturing a liquid crystal display device according to claim 1,
The shape of the opening is a comb-like shape in which one end in the longitudinal direction is closed and the other end is open,
The correction pattern portion is
The light transmitting pattern or the non-light transmitting pattern of the basic pattern portion is extended corresponding to the portion on the one side end portion, and the light transmitting pattern or the non light transmitting surface of the basic pattern portion is extended to correspond to the portion on the other side end portion. An exposure mask for manufacturing a liquid crystal display device, wherein the exposure mask is a partial correction pattern for reducing an optical pattern. The exposure mask for manufacturing a liquid crystal display device according to claim 2,
The correction pattern portion is
When the direction in which the end in the longitudinal direction extends and the angle of inclination formed with the rubbing direction for initial alignment of the liquid crystal molecules is a positive angle,
A translucent pattern or a non-translucent pattern is extended to the end portions in the longitudinal direction corresponding to the circular second quadrant portion and fourth quadrant portion with the longitudinal direction extending as the X axis and the vertical direction as the Y axis. A partial correction pattern is provided,
When the tilt angle is a negative angle,
A partial correction pattern for extending a translucent pattern or a non-translucent pattern is provided at the end in the longitudinal direction corresponding to at least the first quadrant or the third quadrant of the circle. Exposure mask. The exposure mask for manufacturing a liquid crystal display device according to claim 3,
The correction pattern portion is
When the direction in which the end in the longitudinal direction extends and the angle of inclination formed with the rubbing direction for initial alignment of the liquid crystal molecules is a positive angle,
A partial correction pattern for reducing the translucent pattern or the non-translucent pattern is provided at the end in the longitudinal direction corresponding to the circular fourth quadrant having the longitudinal direction as the X axis and the vertical direction as the Y axis. And
When the tilt angle is a negative angle,
An exposure mask for manufacturing a liquid crystal display device, wherein a partial correction pattern for reducing a translucent pattern or a non-translucent pattern is provided at an end in the longitudinal direction corresponding to the circular first quadrant. In the exposure mask for manufacturing a liquid crystal display device according to claim 4 or 5,
The correction pattern portion is
An exposure mask for manufacturing a liquid crystal display device having a pattern size smaller than a minimum pattern size of the basic pattern portion.   Using the exposure mask for manufacturing a liquid crystal display device according to any one of claims 1 to 6, an opening is formed on at least one side electrode of a pair of electrodes for driving liquid crystal molecules, and an opening electrode is formed. A method for manufacturing a liquid crystal display device.

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