Mask, spacer, and display substrate

Abstract

The application discloses a mask, a spacer and a display substrate. The mask comprises an opaque area and a light-transmitting area; the light-transmitting area comprises a main body pattern, and the main body pattern is in a polygonal shape; the light-transmitting area further comprises an outward-expanding pattern, which is arranged at a corner position of the main body pattern and outward expands from the corner position to a direction away from the main body pattern; the light-transmitting area further comprises a compensation pattern, and a region of one side of the main body pattern away from the main body pattern is provided with the compensation pattern, and a normal projection of the compensation pattern to the side falls between two ends of the side; at least one corner position of the main body pattern is provided with the outward-expanding pattern, and the compensation pattern is arranged at two sides corresponding to the corner. The mask of the application performs exposure compensation on the corner of the spacer, reduces passivation at the corner position of the spacer, and increases the actual supporting area of the spacer. The actual supporting effect of the spacer is improved without increasing the size of the spacer.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of display, in particular to a mask, a spacer and a display substrate. BACKGROUND

[0002] The liquid crystal display panel part is mainly composed of an array substrate, a color film substrate and liquid crystal between the two. The color film substrate is provided with a color resistance layer for color filtering and a columnar spacer for supporting the thickness of the liquid crystal cell. In order to make the film surface uniform after cell forming and reduce the risk of low-temperature bubble and gravity Mura, the columnar spacer is often designed in two sections (main spacer / sub spacer) or three sections (main spacer / sub1 spacer / sub2).

[0003] The mask design of the columnar spacer is mainly divided into a conventional type and a semi-transparent membrane type. The main spacer and the sub spacer of the conventional columnar spacer are both full-transmission patterns. The step difference is generally controlled by controlling the opening size of the full-transmission pattern. The semi-transparent membrane type columnar spacer generally uses a full-transmission pattern for the main spacer and a semi-transmission pattern for the sub spacer. The transmittance of the semi-transmission pattern is generally fixed, and the transmittance of the semi-transmission pattern is given according to the step difference requirement.

[0004] When the semi-transparent mask is used to manufacture the columnar spacer, the light intensity at the center of the semi-transparent pattern will be different from that at other positions when the opening value of the semi-transparent pattern exceeds a certain value, which may cause the corner of the spacer to be blunt, reduce the actual supporting area of the spacer, and thus cause the risk of liquid crystal display panel touch pressure related defects. SUMMARY

[0005] The purpose of the present application is to provide a mask, a spacer and a display substrate capable of corner correction.

[0006] The present application discloses a mask, which comprises:

[0007] An opaque area;

[0008] A light-transmitting area, the light-transmitting area comprising:

[0009] A main pattern, the main pattern being in a polygonal shape;

[0010] An outward expansion pattern, the outward expansion pattern being arranged at a corner position of the main pattern, the outward expansion pattern expanding outward from the corner position away from the main pattern;

[0011] A compensation pattern, one side of the main pattern being provided with the compensation pattern, the compensation pattern being projected onto the side of the main pattern between the two ends of the side;

[0012] The outer expansion pattern is arranged at at least one corner position of the main body pattern, and two sides corresponding to the corner position are provided with the compensation pattern.

[0013] Optionally, the outer expansion pattern is arranged at all corner positions of the main body pattern, and the compensation pattern is arranged at all side positions of the main body pattern.

[0014] Optionally, the number of the outer expansion pattern is equal to the number of the compensation pattern.

[0015] Optionally, the main body pattern is a square, the outer expansion pattern is a square, and the compensation pattern is a rectangle.

[0016] Optionally, the outer expansion pattern is arranged at all four corner positions of the main body pattern, and the compensation pattern is arranged at all side positions of the main body pattern.

[0017] Optionally, the center of the outer expansion pattern overlaps with a vertex of the main body pattern, and two vertices of the outer expansion pattern are located on two adjacent sides of the main body pattern, respectively.

[0018] Optionally, one side of the compensation pattern is parallel to a side of the main body pattern close to the compensation pattern, and part of the shading area is arranged between the compensation pattern and the side of the main body pattern close to the compensation pattern.

[0019] Optionally, part of the shading area is arranged between the compensation pattern and the outer expansion pattern.

[0020] Optionally, the side length of the main body pattern is a, the side length of the outer expansion pattern is x, the distance between the compensation pattern and the side of the main body pattern close to the compensation pattern is b, the side length of the side of the compensation pattern parallel to the side of the main body pattern close to the compensation pattern is w, and the side length of the side of the compensation pattern vertical to the side of the main body pattern close to the compensation pattern is h.

[0021] 32μm≤a≤44μm, 2μm≤h≤4μm, 2μm≤b≤4μm, 6μm≤x≤8μm, and the w=a-√2x.

[0022] Optionally, the side length of the main body pattern is a, the side length of the outer expansion pattern is x, the distance between the compensation pattern and the side of the main body pattern close to the compensation pattern is b, the side length of the side of the compensation pattern parallel to the side of the main body pattern close to the compensation pattern is w, and the side length of the side of the compensation pattern vertical to the side of the main body pattern close to the compensation pattern is h.

[0023] The h=(4a) / 44, the b=(3a) / 44, the x=(7a) / 44, and the w=a-√2x.

[0024] Optionally, the mask includes a plurality of the light-transmissive regions; the plurality of the light-transmissive regions include full light-transmissive regions and / or half light-transmissive regions; the full light-transmissive regions are used to prepare main spacers on the display substrate, and the half light-transmissive regions are used to prepare secondary spacers on the display substrate.

[0025] The present application also provides a spacer, a fillet radius of a corner of the spacer is R, a lateral dimension of the spacer is TX, and a longitudinal dimension of the spacer is TY; when a height compression of the spacer is 55% of an original height, the R is greater than or equal to 1 / 6TX and less than or equal to 1 / 4TX or the R is greater than or equal to 1 / 6TY and less than or equal to 1 / 4TY.

[0026] Optionally, the spacer is prepared using a mask, a side length of an opening pattern of the mask is a, and in a normal state:

[0027] R=0.0013a 3 -0.152a 2 +5.521a-56.236

[0028] TX=-0.0014a 3 +0.157a 2 -4.703a+69.741

[0029] TY=-0.0004a 3 +0.045a 2 -0.518a+17.759.

[0030] Optionally, a height of a middle region of a top of the spacer is greater than or equal to a height of a corner region of the top of the spacer.

[0031] Optionally, an included angle between a sidewall of the spacer and a horizontal plane is less than 30°.

[0032] Optionally, an elastic recovery rate of the spacer is greater than or equal to 90% and less than or equal to 95%.

[0033] The present application also provides a display substrate, which includes the above spacer.

[0034] Compared with the related art, the mask plate of the present application reduces passivation at the position of the spacer corner by performing exposure compensation on the spacer corner, and increases the actual support area of the spacer. The actual support effect of the spacer is improved without increasing the size of the spacer; or the size of the spacer can be reduced, the width of the BM is reduced, and the transmittance of the display panel is improved without changing the actual support effect of the spacer.

[0035] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present specification. BRIEF DESCRIPTION OF DRAWINGS

[0036] The accompanying drawings incorporated in the specification hereof and forming a part thereof illustrate embodiments consistent with the present specification and together with the description are used to explain the principles of the present specification.

[0037] Figure 1 Data graph of the relationship between the chamfer size of the mask plate of the present application and the round corner of the spacer.

[0038] Figure 2 Structure schematic diagram of the mask plate in the related art.

[0039] Figure 3 Data comparison graph of the mask plate of the present application with or without compensation pattern.

[0040] Figure 4 Structure schematic diagram of the mask plate in an embodiment of the present application.

[0041] Figure 5 Structure schematic diagram of the mask plate in another embodiment of the present application.

[0042] Figure 6 Structure schematic diagram of the mask plate in another embodiment of the present application.

[0043] Figure 7 Structure schematic diagram of the mask plate in another embodiment of the present application.

[0044] Figure 8 Structure schematic diagram of the mask plate in another embodiment of the present application.

[0045] Figure 9 Data graph of the relationship between the main pattern size of the mask plate of the present application and the round corner of the spacer.

[0046] Figure 10 Data graph of the relationship between the compensation pattern size of the mask plate of the present application and the round corner of the spacer.

[0047] Figure 11 Data graph of the relationship between the compensation pattern size of the mask plate of the present application and the round corner of the spacer.

[0048] Figure 12 Data graph for mask outer extension pattern size and spacer corner relationship of the present application.

[0049] Figure 13 Data graph for spacer size and mask size relationship of the present application.

[0050] Figure 14 Data comparison graph for improved spacer and conventional spacer of the present application. DETAILED DESCRIPTION

[0051] The exemplary embodiments will be described in detail herein with reference to the attached drawings. In the following description, like reference numerals refer to like elements, unless the context clearly dictates otherwise. The following description is not intended to represent all embodiments in accordance with the present description. Rather, they merely represent exemplary devices and methods in accordance with some aspects of the present description, as detailed in the appended claims.

[0052] The terminology used in the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. Unless otherwise defined, technical and scientific terms used in this description and claims are intended to have the meanings commonly understood by one of ordinary skill in the art. The use of the terms "first", "second", and "like" in this description and claims does not constitute a limitation on the order of these elements, but rather is used to distinguish one element from another. Also, the use of "a" or "an" does not constitute a limitation on the number of such elements, but rather means that there is at least one of such element. The use of "multiple" or "plurality" means two or more. The use of "front", "back", "top", and / or "bottom" and like terms is used for ease of description and is not intended to limit the position or spatial orientation of the apparatus. The use of "include", "includes", "including" and / or "contain", "contains", "containing" and like terms is not intended to be limiting and is understood to encompass the elements listed thereafter and equivalents thereof, as well as additional elements. The use of "connect" or "connected" and like terms is not limited to a direct or physical connection and can include an electrical connection, whether direct or indirect.

[0053] The terminology used in the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. The use of the terms "a", "an" and "the" in this description and claims are intended to refer to one or more than one, unless otherwise indicated by context. It will also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0054] A mask is a patterning template used in photolithography to transfer a pattern to a product carrier in an exposure process. Since the first generation of masks in 1993, large size, thin line width, and fewer processes have been the ultimate optimization direction of masks. The photo spacer in a thin film transistor liquid crystal display (TFT-LCD) is a key structure for supporting the thickness of the box, and is often made using a half-tone mask to reduce the process, using a full-tone pattern to make the main photo spacer (Main PS), and using a half-tone pattern to make the sub photo spacer (Sub PS) to form a step difference.

[0055] As shown in Figure 1 , the PS mask design factors mainly include TX (lateral size), TY (longitudinal size), C (four corner chamfer size), and HT Tr (transmittance). When C increases, the difference between the PS profile and the mask shape also gradually increases, transitioning from a rectangle to a circle. When using a proximity exposure machine to manufacture a photo spacer, the actual exposure pattern compared to the mask design pattern, the corner position is limited by diffraction, and the high-frequency part reflecting the corner in the intensity spectrum cannot be effectively projected to the carrier substrate, causing the corner to be blunted. At this time, the circumscribed rectangle of the columnar photo spacer does not change in length, and the pixel aperture ratio of the display panel does not change. However, due to the blunting of the corners, the original polygonal effective support area is actually a circle / ellipse inscribed in the original polygon when manufactured. The support area at the corner position is lost due to exposure, resulting in a significant reduction in the effective support area of the actual photo spacer, leading to a decrease in product transmittance and insufficient support strength in the box, resulting in yield loss. Moreover, the PS profile and the mask size cannot remain consistent, even if C is reduced to 0, the mask is a rectangle, and the PS profile only has four corner radii R that are relatively reduced and cannot be reduced to 0. At this time, the PS effective support area is a circumscribed corner rectangle under a fixed TX / TY rectangle. Considering TX = TY = a, when the four corner radii R are larger, the PS effective support area lost is larger, and when R increases to the limit a / 2, the minimum effective contact area appears - a circle with a radius of R, as shown in 1-5 in Figure 1 . At this time, the PS effective contact area can be calculated using the approximate formula:

[0056] S = a 2 +(π-4)R 2 , where S ∈ [πR 2 , a 2 ]

[0057] The cell thickness is supported by the Main PS. When subjected to external pressure and LC fluctuations, the cell thickness compresses the Sub PS, causing it to contact and support the opposite substrate, thus stabilizing the cell space. When the Sub PS support density is insufficient, the cell space is rapidly compressed, causing the Main PS to be compressed to plastic deformation or collapse. After the load is released, the cell space cannot return to its initial state, resulting in transmittance differences and causing gap defects.

[0058] Increasing the density of Sub PS can effectively improve gap defects, but without other design optimizations, increasing the Sub PS size is the only strategy. However, when the panel experiences relative sliding on the T / C side, an excessively large size can easily cause the PS to scratch the alignment film on the opposite side, leading to LC disorder and light leakage. Therefore, increasing the Sub PS size requires matching a larger BM to block potential light leakage areas, directly resulting in a lower panel pixel aperture ratio / transmittance.

[0059] like Figure 2 and Figure 3 As shown, the illustration provides a photomask including a main shape 21 and an outer shape 22. The main shape 21 is a square, and the outer shape 22 is also a square. The outer shape 22 is positioned at a corner of the main shape 21. Optionally, the outer shape 22 is positioned at each of the four corners of the main shape 21. The centroid of the outer shape 22 overlaps with a vertex of the main shape 21, and the two vertices of the outer shape 22 closest to the main shape 21 are located on the two adjacent sides of the main shape 21 closest to the outer shape 22. That is, one-quarter of the area of ​​the outer shape 22 overlaps with the main shape 21 (i.e.,...). Figure 2 (In the L region). At this point, due to the overall weak light intensity of the Half-Tone, the fabricated septum shrinks inward around its perimeter, causing distortion. The 2D morphology is not effectively improved, and the corner distortion is severe, easily leading to peeling or damage. Simultaneously, the septum exhibits severe cratering, with a pit depth of 0.085 μm. The PS Bottom Size is not compensated for, and the cross-sectional Taper is consistent with the Normal Half-Tone, showing a uniform gradient. This septum structure cannot provide effective support.

[0060] like Figure 4 and Figure 5 As shown, to solve the above problems, this application provides a photomask for fabricating spacers on a display substrate, comprising:

[0061] Shading area 10;

[0062] A plurality of light-transmitting areas 20, wherein the light-transmitting areas 20 include:

[0063] Main graphic 21, which is polygonal in shape;

[0064] An outer expansion pattern 22 is arranged at a corner position of the main body pattern 21, and the outer expansion pattern 22 expands outward from the corner position away from the main body pattern 21;

[0065] A compensation pattern 23 is arranged at one side of one edge of the main body pattern 21, and the compensation pattern 23 is projected onto the edge between the two ends of the edge.

[0066] The outer expansion pattern 22 is arranged at a corner position of the main body pattern 21, and the corner corresponds to two edges each of which is provided with the compensation pattern 23.

[0067] To solve the above technical problems, the present application further provides a spacer, which is manufactured by using the mask as mentioned above.

[0068] To solve the above technical problems, the present application further provides a display substrate, which comprises the spacer as mentioned above.

[0069] The present application reduces passivation at the corner position of the spacer by performing exposure compensation on the corner of the spacer, and increases the actual supporting area of the spacer. The actual supporting effect of the spacer is improved without increasing the size of the spacer. From the perspective of the supporting ability in the box, the PS contact area is improved by only reducing the radius of the four corners without increasing TX / TY, the maximum area is a rectangle, and the minimum area is a circle. Considering TX=TY=a:

[0070] Theoretical improvement range=(a 2 -πa 2 / 4) / (πa 2 / 4)=27.3%

[0071] The size of the spacer can also be reduced without changing the actual supporting effect of the spacer, the width of the BM is reduced, and the transmittance of the display panel is improved.

[0072] The various embodiments of the present application in accordance with the above creative concept will be described in detail below.

[0073] As Figures 4 to 8As shown, the present application provides a mask, which includes an opaque area 10 and a plurality of light-transmitting areas 20. The light-transmitting area 20 is composed of a main body pattern 21, an outward expansion pattern 22 and a compensation pattern 23. The main body pattern 21 is a polygon. Optionally, the number of sides of the main body pattern 21 can be set according to actual conditions. The main body pattern 21 can be a triangle, a quadrilateral, a pentagon or other polygons. The main body pattern 21 can be a regular polygon or not. The length of each side of the main body pattern 21 and the angle of each corner can be set according to actual requirements. The outward expansion pattern 22 is arranged at a corner position of the main body pattern 21. The outward expansion pattern 22 expands outward from the corner position of the main body pattern 21. The shape of the outward expansion pattern 22 can be set according to actual requirements. The outward expansion pattern 22 can be a regular shape, such as a circle, an ellipse, a polygon or a semicircle. The outward expansion pattern 22 can also be an irregular shape. It is only required that the outward expansion pattern 22 expands outward from the corner position of the main body pattern 21. The compensation pattern 23 is arranged at a side of the main body pattern 21 away from the main body pattern 21. The shape of the compensation pattern 23 can be set according to actual requirements. The compensation pattern 23 can be a regular shape, such as a circle, an ellipse, a polygon or a semicircle. The compensation pattern 23 can also be an irregular shape. It is only required that the compensation pattern 23 is arranged at a side of the main body pattern 21 away from the main body pattern 21. The corner position of the main body pattern 21 is provided with the outward expansion pattern 22. The two sides corresponding to the corner provided with the outward expansion pattern 22 are provided with the compensation pattern 23.

[0074] In an optional embodiment, the mask includes a plurality of light-transmitting areas 20. The plurality of light-transmitting areas 20 are full light-transmitting areas. The full light-transmitting areas are used for preparing main spacers on a display substrate. The position distribution of the light-transmitting areas 20 on the mask is set according to the position setting of the main spacers on the display substrate.

[0075] In an optional embodiment, the mask includes a plurality of light-transmitting areas 20. The plurality of light-transmitting areas 20 are half light-transmitting areas. The half light-transmitting areas are used for preparing auxiliary spacers on a display substrate. The position distribution of the light-transmitting areas 20 on the mask is set according to the position setting of the auxiliary spacers on the display substrate.

[0076] In an optional embodiment, the mask includes a plurality of light-transmitting areas 20. The plurality of light-transmitting areas 20 include a plurality of full light-transmitting areas and a plurality of half light-transmitting areas. The full light-transmitting areas are used for preparing main spacers on a display substrate. The half light-transmitting areas are used for preparing auxiliary spacers on the display substrate. The position distribution of the light-transmitting areas 20 on the mask is set according to the position setting of the main spacers and the auxiliary spacers on the display substrate.

[0077] In an optional embodiment, an outward-expanding shape 22 is provided at all corner positions of the main shape 21. A compensation shape 23 is provided at all sides of the main shape 21. The number of outward-expanding shapes 22 is equal to the number of compensation shapes 23. For example, if the main shape 21 is a triangle, then an outward-expanding shape 22 extending outwards away from the main shape 21 is provided at each of the three corner positions of the main shape 21, and a compensation shape 23 is provided on the side of each of the three sides of the main shape 21 away from the main shape 21. When the main shape 21 is a pentagon, then an outward-expanding shape 22 extending outwards away from the main shape 21 is provided at each of the five corner positions of the main shape 21, and a compensation shape 23 is provided on the side of each of the five sides of the main shape 21 away from the main shape 21.

[0078] like Figures 4 to 6 As shown, in an optional embodiment, the main shape 21 is a square, the outer shape 22 is also a square, and the compensation shape 23 is a rectangle. Optionally, the centroid of the outer shape 22 overlaps with a vertex of the main shape 21, and the two vertices of the outer shape 22 closest to the main shape 21 are located on the adjacent sides of the main shape 21 closest to the outer shape 22. That is, one-quarter of the area of ​​the outer shape 22 overlaps with the main shape 21 (i.e., Figure 6 (In the L region). Optionally, one side of the compensation graphic 23 is set parallel to the side of the main graphic 21 near the compensation graphic 23, and a partial shading area 10 is provided between the compensation graphic 23 and the side of the main graphic 21 near the compensation graphic 23. For example, the compensation graphic 23 is rectangular, and the long side of the compensation graphic 23 is set parallel to the side of the main graphic 21 near the compensation graphic 23. There is a gap area between the compensation graphic 23 and the main graphic 21, which is filled by the partial shading area 10. There is no overlapping area between the outward expansion graphic 22 and the compensation graphic 23, that is, there is a gap area between the outward expansion graphic 22 and the compensation graphic 23, which is filled by the partial shading area 10. Optionally, outward expansion graphics 22 extending outward away from the main graphic 21 are provided at each of the four corners of the main graphic 21, and compensation graphics 23 are provided on the side of each of the four sides of the main graphic 21 away from the main graphic 21. That is, the four outward expansion graphics 22 expand outward from the four corners of the main graphic 21 in a direction away from the main graphic 21, and the four compensation graphics 23 are respectively set on the side of the four sides of the main graphic 21 away from the main graphic 21.

[0079] Optionally, the side length of the main graphic is *a*. The side length of the extended graphic is *x*. The distance between the compensation graphic and the side of the main graphic closest to the compensation graphic is *b*. The side length of the side of the compensation graphic parallel to the side of the main graphic closest to the compensation graphic is *w*. The side length of the side of the compensation graphic perpendicular to the side of the main graphic closest to the compensation graphic is *h*. The grid width *h* is a direct influencing factor on the projected light flux, significantly affecting the PS edge morphology formed after photopolymerization. Since the grid width limit depends on the process resolution of the photomask supplier, and when the width approaches the 1μm resolution limit, the linewidth uniformity will also deteriorate, which is not conducive to improving the uniformity of large-size products. In this embodiment, the design is based on a width *h* and *w* ≥ 2μm. Considering the PSSize design range under the actual G10.5 generation TV product resolution, the final defined size range is 32μm≤a≤44μm, 2μm≤h≤4μm, 2μm≤b≤4μm, 6μm≤x≤8μm. One-way variable analysis was performed within the defined size range.

[0080] like Figure 6 and Figure 9 As shown, under center exposure conditions, the selected values ​​of 'a' are 32μm, 36μm, 40μm, and 44μm, respectively, while other values ​​remain unchanged for simulation. When the value of 'a' changes, the fillet radius R of a conventional PS decreases as 'a' increases. That is, when the exposure aperture is narrower, the high-frequency components at the corners are weaker, resulting in a stronger diffraction effect, a more severe corner passivation effect, and a larger fillet radius R; conversely, when the exposure aperture is wider, the high-frequency components at the corners are stronger, resulting in a weaker diffraction effect, a milder corner passivation effect, and a smaller fillet radius R. Under conventional designs, a larger opening approaches a rounded rectangle, while a smaller opening approaches a circle. The cross-sectional profiles under four opening sizes ('a') of 32μm, 36μm, 40μm, and 44μm are compared. As the opening increases, light wave interference at the opening boundary weakens the light intensity at the opening center, resulting in a concave "crater" shape on the top surface of the PS. The larger the opening (within the 32–44 μm range), the deeper the crater, reaching a maximum depth of 0.04 μm. When the PS is supported inside a box, this "crater" shape at the top can drastically reduce the PS support area, affecting the product's actual compressive strength.

[0081] like Figure 6 and Figure 10As shown, under center exposure conditions, the selected h values ​​were 2μm, 3μm, and 4μm, with other values ​​remaining unchanged for simulation. When the h value changed, the corner radius R of the rectified PS was positively correlated with the h value. That is, the larger the h value, the more severe the corner passivation effect, and the larger the corner radius R; the smaller the h value, the milder the corner passivation effect, and the smaller the corner radius R. However, from Image 2D / 3D observation, when the h value was small, the PS morphology already showed four-corner distortion, resulting in a smaller measured corner radius R, while the actual effective contact area of ​​the PS remained unchanged. From the perspective of the PS bottom taper, after PS optical correction, a large base appears at the bottom, increasing the bottom size compared to conventional designs, which would improve the PS elastic recovery rate to some extent.

[0082] like Figure 6 and Figure 11 As shown, under center exposure conditions, the selected values ​​of b were 2μm, 3μm, and 4μm, while other values ​​remained unchanged for simulation. When the value of b changed, the corner radius R for the corrected PS was negatively correlated with the size of b. That is, the smaller b was, the more severe the corner blunting effect, and the larger the corner radius R; the larger b was, the milder the corner blunting effect, and the smaller the corner radius R. Comparing with Image 2D / 3D observations, decreasing b slightly improved the image, but corner distortion effects remained. When b increased, the PS Taper became smoother, the PS Bottom Size approached the conventional design, and the PS elastic recovery rate decreased to some extent.

[0083] like Figure 6 and Figure 12 As shown, under center exposure conditions, the selected x values ​​were 6μm, 7μm, and 8μm, with other values ​​remaining unchanged for simulation. When the x value changed, the corner radius R for correcting the PS was positively correlated with the x value. That is, the larger the x value, the more severe the corner blunting effect, and the larger the corner radius R; the smaller the x value, the milder the corner blunting effect, and the smaller the corner radius R. However, when the x value changed, the overall PS distortion was severe in Image 2D / 3D observations, and the corner radius R did not actually improve the effective contact area of ​​the PS.

[0084] Based on the exposure effect of the pattern tested using single-factor variables, the design objectives were to achieve a smaller PS corner radius R after optical correction, no corner distortion in PS2D / 3D, and a rectangular shape (rounded rectangle). The optimal values ​​were h = (4a) / 44, b = (3a) / 44, and x = (7a) / 44. The values ​​of h, b, x, and w are used to optimize the floating style for edge optical correction in this solution. When the value of 'a' changes due to the actual product PS Size requirements, the values ​​of h, b, x, and w change accordingly.

[0085] like Figure 6 and Figure 13 As shown, the corner radius of the spacer is R, the lateral dimension of the spacer is TX, and the longitudinal dimension of the spacer is TY. Using Mask CD a as the independent variable and Corner Radius R, PS TX, and PS TY as dependent variables, the optical correction effects under different exposure gaps are summarized and compared. Under Center Recipe exposure conditions, R / TX / TY are correlated with a. Their changing trends conform to the third-order equation of a:

[0086] R = 0.0013a 3 -0.152a 2 +5.521a-56.236

[0087] TX = -0.0014a 3 +0.157a 2 -4.703a+69.741

[0088] TY = -0.0004a 3 +0.045a 2 -0.518a+17.759

[0089] Depending on the selected exposure process conditions, the optimized CornerRadius R, PS TX, and PS TY can be calculated using the above empirical formulas to correct the theoretical PS support area and the internal compressive strength of the cell.

[0090] like Figure 14As shown, in an optional embodiment, when the Corner Radius R is reduced, the four corners of the PS can provide support, and the effective support area per unit area of the PS is increased. Thus, under the same compression strength design, i.e., under the condition that the same support is provided per unit area of the PS, the design Mask CD a can be reduced. Further, the width of the BM can be reduced, thereby improving the pixel aperture ratio and the transmittance of the display panel. Based on the G10.5 TV product performance, under the premise that the PS contact density is consistent after the PS is compressed in the PS box, the PS TX / PS TY can be reduced by about 3.2 μm by using the corner correction scheme of the present application. When the height compression of the spacer is 55% of the original height, and the Top Area is 1400 μ㎡ at this time, the improved Corner Radius R is greater than or equal to 1 / 6TX and less than or equal to 1 / 4TX, or R is greater than or equal to 1 / 6TY and less than or equal to 1 / 4TY, for example, the improved Corner Radius R can be 1 / 6TX, 5 / 24TX, 3 / 16TX, 11 / 48TX, or 1 / 4TX, etc. The improved Corner Radius R can also be 1 / 6TY, 5 / 24TY, 3 / 16TY, 11 / 48TY, or 1 / 4TY, etc. In the present embodiment, the improved Corner Radius R is reduced from 12.6 μm to 8.1 μm, which is about 1 / 5TX. The crater depth is reduced from 0.09 μm to 0, and the PS Bottom CD is increased by 7 μm. Due to the improvement of the overall PS shape, the actual PS elastic recovery rate is increased from 88.9% to 93.3% (an increase of 5%), thereby further improving the compression resistance in the box.

[0091] In an optional embodiment, when the PS TX / TY is reduced, the expanded BM can be narrowed accordingly to avoid the risk of red and blue spots. In small-size high-resolution products, the product aperture ratio improvement caused by the inward shrinkage of the BM will significantly affect the product transmittance.

[0092] The present application also provides a spacer formed using the mask plate.

[0093] The Corner Radius R of the spacer at the corner is R, the lateral dimension of the spacer is TX, and the longitudinal dimension of the spacer is TY. When the height compression of the spacer is 55% of the original height, R is greater than or equal to 1 / 6TX and less than or equal to 1 / 4TX, or R is greater than or equal to 1 / 6TY and less than or equal to 1 / 4TY. For example, R can be 1 / 6TX, 5 / 24TX, 3 / 16TX, 11 / 48TX, or 1 / 4TX, etc. R can also be 1 / 6TY, 5 / 24TY, 3 / 16TY, 11 / 48TY, or 1 / 4TY, etc.

[0094] The spacer is prepared using a mask plate, the side length of the opening pattern of the mask plate is a, and in the normal state:

[0095] R = 0.0013a 3 -0.152a 2 +5.521a - 56.236

[0096] TX = -0.0014a 3 +0.157a 2 -4.703a + 69.741

[0097] TY = -0.0004a 3 +0.045a 2 -0.518a + 17.759

[0098] The height of the middle region of the spacer top is greater than or equal to the height of the corner region. The angle between the sidewall of the spacer and the horizontal plane is less than 30°, for example, the angle between the sidewall of the spacer and the horizontal plane can be 15°, 18°, 20, 25°, or 29°, etc. The elastic recovery rate of the spacer is greater than or equal to 90% and less than or equal to 95%, for example, the elastic recovery rate of the spacer can be 90%, 91%, 92%, 93.3%, or 95%, etc.

[0099] The application also provides a display substrate comprising the spacer as described above.

[0100] The application preliminarily simulates the corner light intensity distribution by using a numerical simulation method, and outputs the optimal pattern size ratio. Exposure testing is carried out based on a G10.5 generation line, the simulation results are calibrated by using measured values, the influence of each corner design parameter on the PS morphology is determined by fixing a single variable, and the optimal design scheme of the corner compensation is determined. The method of using the outward expansion pattern in cooperation with the compensation pattern is used to compensate the exposure loss of the corner. The optimal PS corner optimization mask standard style suitable for proximity exposure machines (200-300 μm) is obtained. And the PS morphology is changed from a circular shape to a rectangular shape, the optimization amplitude of the circular radius is more than 30%, the support area in the PS box is increased by 10%, and the transmittance of the 8K product is increased by 2.8%. At the same time, the application provides a layout structure for the spacer made by other exposure methods, and an exposure theoretical model and data related to the layout structure.

[0101] Other embodiments of this application are within the scope of the following claims: for one skilled in the art, after considering this specification, will readily come up with other ways of carrying out the application of the present specification. The present specification is intended to encompass any variations, uses, or adaptations of the present specification following the general principles of the present specification and including those not specifically delineated herein. The specification and examples are to be regarded in an illustrative rather than a restrictive sense, and the true scope and spirit of the present specification are indicated by the following claims.

[0102] It is to be understood that the present description is not limited to the precise construction herein described and as shown in the attached drawings, and that various modifications and changes can be made by those skilled in the art without departing from the scope thereof. The scope of the description is indicated only by the appended claims.

[0103] The above description is merely the preferred embodiments of the present description and is not intended to limit the present description. It is understood by those skilled in the art that any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present description shall be included in the scope of the present description.

Claims

1. A photomask for fabricating spacers on a display substrate, characterized in that, include: Shaded area; The light-transmitting area includes: The main graphic element is polygonal in shape. An expanding graphic is provided at one corner of the main graphic, and the expanding graphic extends outward from the corner in a direction away from the main graphic; The compensation graphic is provided in a region on one side of the main graphic that is away from the main graphic, and the orthographic projection of the compensation graphic onto the side falls between the two ends of the side. The main graphic has an extended graphic at at least one corner, and the compensation graphic is provided on both sides corresponding to the corner.

2. The photomask according to claim 1, characterized in that, The outer expansion graphic is provided at all corner positions of the main graphic; the compensation graphic is provided at all edge positions of the main graphic.

3. The photomask according to claim 2, characterized in that, The number of the extended graphics is equal to the number of the compensation graphics.

4. The photomask according to claim 1, characterized in that, The main graphic is a square, the outer expansion graphic is a square, and the compensation graphic is a rectangle.

5. The photomask according to claim 4, characterized in that, The main body graphic has an expansion graphic at each of its four corners; the main body graphic has a compensation graphic at each of its edges.

6. The photomask according to claim 4, characterized in that, The centroid of the expanded shape overlaps with one vertex of the main shape, and two vertices of the expanded shape are located on adjacent sides of the main shape.

7. The photomask according to claim 4, characterized in that, One side of the compensation graphic is set parallel to the side of the main graphic that is close to the compensation graphic, and a portion of the light-blocking area is provided between the compensation graphic and the side of the main graphic that is close to the compensation graphic.

8. The photomask according to claim 7, characterized in that, A portion of the light-blocking area is provided between the compensation pattern and the expanded pattern.

9. The photomask according to any one of claims 4-8, characterized in that, The side length of the main graphic is a, the side length of the outer graphic is x, the distance between the compensation graphic and the side of the main graphic closest to the compensation graphic is b, the side length of the compensation graphic parallel to the side of the main graphic closest to the compensation graphic is w, and the side length of the compensation graphic perpendicular to the side of the main graphic closest to the compensation graphic is h. 32μm≤a≤44μm, 2μm≤h≤4μm, 2μm≤b≤4μm, 6μm≤x≤8μm, the .

10. The photomask according to any one of claims 4-8, characterized in that, The side length of the main graphic is a, the side length of the outer graphic is x, the distance between the compensation graphic and the side of the main graphic closest to the compensation graphic is b, the side length of the compensation graphic parallel to the side of the main graphic closest to the compensation graphic is w, and the side length of the compensation graphic perpendicular to the side of the main graphic closest to the compensation graphic is h. The h = (4a) / 44, the b = (3a) / 44, the x = (7a) / 44, the .

11. The photomask according to claim 1, characterized in that, The photomask includes a plurality of light-transmitting areas; the plurality of light-transmitting areas include fully light-transmitting areas and / or semi-light-transmitting areas; the fully light-transmitting areas are used to prepare the main spacer on the display substrate, and the semi-light-transmitting areas are used to prepare the secondary spacer on the display substrate.

12. A spacer, characterized in that, The spacer is prepared using the mask as described in any one of claims 1-11. The radius of the rounded corners of the spacer is R. The lateral dimension of the spacer is TX. The longitudinal dimension of the spacer is TY. When the height of the spacer is compressed to 55% of its original height, R is greater than or equal to 1 / 6TX and less than or equal to 1 / 4TX or R is greater than or equal to 1 / 6TY and less than or equal to 1 / 4TY.

13. The spacer according to claim 12, characterized in that, The spacer is prepared using a photomask, wherein the side length of the opening pattern of the photomask is 'a', and under normal conditions: 。 14. The spacer according to claim 12, characterized in that, The height of the middle region at the top of the septum is greater than or equal to the height of the corner regions at the top of the septum.

15. The spacer according to claim 12, characterized in that, The angle between the sidewall of the diaphragm and the horizontal plane is less than 30°.

16. The spacer according to claim 12, characterized in that, The elastic recovery rate of the spacer is greater than or equal to 90% and less than or equal to 95%.

17. A display substrate, characterized in that, The display substrate includes the spacer as described in any one of claims 12-16.

Images