Mask plate and design method thereof

Abstract

The present application provides a mask plate and a design method thereof, wherein the mask plate is used for vapor deposition on a display substrate and comprises: a plurality of vapor deposition openings arranged in an array, the vapor deposition openings comprising a reference region and a compensation region, the vapor deposition openings corresponding to pixel openings of the display substrate, the pixel openings comprising a plurality of arc-shaped opening regions and a linear opening region between two adjacent arc-shaped opening regions, the reference region corresponding to the arc-shaped opening region, the compensation region corresponding to the linear opening region, the vapor deposition openings being used to allow vapor deposition material to pass through; the vapor deposition openings extending along a first direction and penetrating the mask plate, the opening shape of the vapor deposition openings being a polygon tangent to the pixel openings, the first direction being the thickness direction of the mask plate; and a buffer region, the buffer region being used to block the vapor deposition material. The technical solution of the present application effectively improves the vapor deposition shadow problem of the display substrate, thereby improving the color mixing problem of the display substrate.

Description

Technical Field

[0001] The present application relates to the technical field of display devices, and more specifically, to a mask plate and a design method thereof. Background Art

[0002] Organic Light Emitting Diode (OLED) has the characteristics of high color gamut, high contrast, flexible self-luminescence, and low power consumption. It is one of the mainstream information display technologies currently used in smart display ports.

[0003] In OLED manufacturing technology, evaporation process is one of the commonly used process methods, and the fine metal mask (FMM) is an important tool in the evaporation process. The shape design of the FMM evaporation opening is related to the evaporation effect of the evaporation material and the size of the evaporation shadow, which has an important impact on the product quality of OLED. Summary of the Invention

[0004] In view of the above problems, the embodiments of the present application provide a mask plate and a design method thereof, which can effectively improve the evaporation shadow problem of the display substrate, thereby improving the color mixing problem of the display substrate.

[0005] In a first aspect, a mask plate is provided for performing vapor deposition on a display substrate, comprising: a plurality of vapor deposition openings arranged in an array, the vapor deposition openings comprising a reference area and a compensation area, the vapor deposition openings corresponding to pixel openings of the display substrate, the pixel openings comprising a plurality of arc-shaped opening areas and a straight opening area between two adjacent arc-shaped opening areas, the reference area corresponding to the arc-shaped opening area, the compensation area corresponding to the straight opening area, the vapor deposition openings being used for allowing vapor deposition material to pass through; the vapor deposition openings extending along a first direction and passing through the mask plate, the opening shape of the vapor deposition openings being a polygon tangent to the pixel opening, and the first direction being the thickness direction of the mask plate; a buffer zone, the buffer zone being used to block the vapor deposition material.

[0006] In combination with the first aspect, in certain implementations of the first aspect, the polygon has at least two centers of symmetry, and the two centers of symmetry are perpendicular to each other.

[0007] In combination with the first aspect, in certain implementations of the first aspect, the evaporation opening includes a first opening portion and a second opening portion, and the first opening portion and the second opening portion are arranged in sequence along a first direction and are connected. In the first direction, the size of the first opening portion is smaller than the size of the second opening portion, and in the second direction, the size of the first opening portion is smaller than the size of the second opening portion, and the second direction is perpendicular to the first direction.

[0008] In combination with the first aspect, in certain implementations of the first aspect, when performing vapor deposition on the display substrate, the vapor deposition material passes through the first opening and the second opening in sequence.

[0009] In combination with the first aspect, in some implementations of the first aspect, the sidewall of the first opening is a curved surface, and the sidewall of the second opening is a curved surface.

[0010] In combination with the first aspect, in certain implementations of the first aspect, a size of the first opening in the second direction gradually decreases along a direction approaching the second opening.

[0011] In combination with the first aspect, in certain implementations of the first aspect, a size of the second opening in the second direction gradually decreases along a direction approaching the first opening.

[0012] In combination with the first aspect, in certain implementations of the first aspect, a size of the first opening in the first direction ranges from 1 μm to 4.5 μm.

[0013] In combination with the first aspect, in certain implementations of the first aspect, the evaporation opening is formed by wet etching.

[0014] In a second aspect, a method for designing a mask plate is provided, the method comprising: determining a first opening shape of an evaporation opening of the mask plate based on design parameters of a pixel opening of a display substrate; wherein the pixel opening comprises a plurality of arc-shaped opening areas and a straight-line opening area between two adjacent arc-shaped opening areas, the first opening shape comprises a plurality of straight-line edges and an arc-shaped line segment connecting any two adjacent straight-line edges of the plurality of straight-line edges, the straight-line edges of the first opening shape correspond to the straight-line opening areas, and the arc-shaped line segments of the first opening shape correspond to the arc-shaped opening areas; taking the vertex of the arc-shaped line segment of the first opening shape as the tangent point, making an external tangent of the arc-shaped line segment and extending the straight-line edge to intersect with the external tangent of the arc-shaped line segment to form a second opening shape, the second opening shape being a polygon tangent to the pixel opening; determining the second opening shape as the opening shape of the evaporation opening; wherein the evaporation opening comprises a reference area and a compensation area, the reference area corresponds to the arc-shaped opening area, and the compensation area corresponds to the straight-line opening area.

[0015] In a third aspect, a mask plate design device is provided, comprising a processor and a memory, wherein the memory is used to store a computer program, and the processor is used to call the computer program so that the design device implements the design method in the above-mentioned second aspect or any possible implementation of the second aspect.

[0016] In a fourth aspect, a readable storage medium is provided, which stores a computer program. When the computer program is executed by a computing device, the computing device implements the design method in the above-mentioned second aspect or any possible implementation of the second aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic diagram of the opening shape of the evaporation opening of the mask plate in the prior art;

[0018] Figure 2 is a schematic structural diagram of a mask plate disclosed in an embodiment of the present application;

[0019] Figure 3 This is a partial cross-sectional view of a mask disclosed in one embodiment of the present application;

[0020] Figure 4 This is a diagram of the opening shape of an evaporation opening of a mask disclosed in one embodiment of the present application;

[0021] Figure 5 This is a diagram of the opening shape of an evaporation opening of a mask disclosed in one embodiment of the present application;

[0022] Figure 6 This is a diagram of the opening shape of an evaporation opening of a mask disclosed in one embodiment of the present application;

[0023] Figure 7 is a schematic structural diagram of a mask plate disclosed in an embodiment of the present application;

[0024] Figure 8 is a schematic structural diagram of a mask plate disclosed in an embodiment of the present application;

[0025] Figure 9 is a schematic structural diagram of a mask plate disclosed in an embodiment of the present application;

[0026] Figure 10 This is a schematic flow chart of a method for designing a mask disclosed in an embodiment of the present application;

[0027] Figure 11 This is a schematic block diagram of a mask design device disclosed in an embodiment of the present application. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0029] The following describes the technical solutions in the embodiments of the present application in conjunction with the accompanying drawings. In the description of the embodiments of the present application, unless otherwise specified, " / " represents "or." For example, A / B can represent A or B. "And / or" in this document is merely a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, or B exists alone.

[0030] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Furthermore, in the description of this embodiment, unless otherwise specified, "plurality" means two or more.

[0031] References to "one embodiment" or "some embodiments" in the embodiments of the present application mean that one or more embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the phrases "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized.

[0032] OLED has the characteristics of high color gamut, high contrast, flexible self-luminescence, and low power consumption. It is one of the mainstream information display technologies currently used in smart display ports.

[0033] In OLED manufacturing technology, evaporation process is one of the commonly used process methods, and FMM is an important tool for evaporation process. FMM is used to evaporate the light-emitting layer material and form pixel patterns on the backplane. Therefore, the quality of FMM is directly related to the display effect of the display device. For example, the shape design of the FMM evaporation opening is related to the size of the evaporation shadow of the evaporation material. The closer the evaporation opening of the FMM is to an arc, the larger the evaporation shadow will be, which will cause color mixing between adjacent pixels and affect the display effect of the display device. For example, refer to Figure 1 (a) is the opening shape of the FMM evaporation opening commonly used in the prior art, and the opening shape includes four straight edges and an arc segment connecting any two adjacent straight edges. Figure 1 (b) in Figure 1 Schematic diagram of the shadow height corresponding to the arc segment area of ​​the evaporation opening in (a), as shown in Figure 1As shown in (b), the shadow height corresponding to the arc segment area of ​​the evaporation opening is L. Figure 1 (c) in Figure 1 Schematic diagram of the shadow height corresponding to the straight edge area of ​​the evaporation opening in (a), as shown in Figure 1 As shown in (c) of FIG. , the shadow height corresponding to the arcuate line segment of the evaporation opening is L'. For example, the evaporation opening can be photographed using a scanning electron microscope. The dimensional relationship between L and L' can be determined based on the scanning electron microscope image. Actual testing shows that L is greater than L'.

[0034] In the preparation process of FMM, wet etching is a commonly used etching method. At present, the corner areas of FMM evaporation openings are mostly arc-shaped. When using wet etching to form FMM evaporation openings, due to the isotropy of wet etching, size compensation is required in the arc-shaped corner areas (otherwise, a larger arc angle will be generated, affecting the pixel spacing) to form the evaporation opening. When using this type of FMM for evaporation, the evaporation shadow area will increase, the spacing between adjacent pixels will be reduced, and the color mixing between adjacent pixels will be affected, affecting the display effect of the display device.

[0035] In view of this, an embodiment of the present application provides a mask plate and a design method thereof. Specifically, the mask plate includes a plurality of evaporation openings arranged in an array, the evaporation openings include a reference area and a compensation area, the evaporation openings correspond to the pixel openings of the display substrate, the pixel openings include a plurality of arc-shaped opening areas and a straight opening area between two adjacent arc-shaped opening areas, the reference area corresponds to the arc-shaped opening area, the compensation area corresponds to the straight opening area, and the evaporation openings are used for allowing the evaporation material to pass through; the evaporation openings extend along a first direction and pass through the mask plate, the opening shape of the evaporation openings is a polygon tangent to the pixel opening, and the first direction is the thickness direction of the mask plate; the buffer zone, the buffer zone is used to block the evaporation material. In the embodiment of the present application, the opening shape of the evaporation opening of the mask plate is designed, and the opening shape is a polygon tangent to the pixel opening, and the opening shape is a straight line edge, excluding an arc edge, so that the shadow height of the mask plate can be reduced. When the mask plate is used to evaporate the display substrate, the evaporation shadow can be reduced. Furthermore, the base area of ​​the evaporation opening corresponds to the arc-shaped opening area of ​​the pixel opening, and the compensation area corresponds to the linear opening area of ​​the pixel opening. This ensures that when the mask is used to perform evaporation on the display substrate, the shapes of the evaporation opening and the pixel opening match, ensuring that the evaporation material can be smoothly deposited through the evaporation opening into the pixel opening. Therefore, using the mask provided in the embodiments of the present application for evaporation can ensure smooth evaporation, reduce evaporation shadows, and avoid color mixing between adjacent pixels, thereby ensuring the display effect of the display device.

[0036] The following describes the embodiments of the present application in detail with reference to the accompanying drawings.

[0037] Figure 2 A schematic structural diagram of a mask plate provided in an embodiment of the present application. Figure 3 A partial cross-sectional view of a mask provided in an embodiment of the present application.

[0038] like Figure 2 As shown, the mask plate 10 includes a plurality of evaporation openings 11 arranged in an array, the evaporation openings 11 correspond to the pixel openings of the display substrate, and the evaporation openings 11 are used for allowing the evaporation material to pass through; and a buffer zone 12, which is used to block the evaporation material.

[0039] Specifically, the pixel opening includes multiple arc-shaped opening areas and a straight opening area between two adjacent arc-shaped opening areas; the evaporation opening includes a reference area and a compensation area, the reference area corresponds to the arc-shaped opening area, and the compensation area corresponds to the straight opening area.

[0040] In this way, when the mask plate 10 is used to perform vapor deposition on the display substrate, the shapes of the vapor deposition opening and the pixel opening can be matched, and the vapor deposition material can be smoothly vapor-deposited into the pixel opening through the vapor deposition opening.

[0041] It should be understood that in the embodiment of the present application, the opening shape of the evaporation opening 11 refers to the shape of the orthographic projection of the evaporation opening 11 on the plane where the surface of the mask plate 10 is located.

[0042] Specifically, if Figure 3 As shown, the evaporation opening 11 extends along the first direction and passes through the mask plate 10 .

[0043] In the embodiment of the present application, the first direction refers to the thickness direction of the mask plate 10, for example, Figure 1 It should be understood that the x direction is only an exemplary description of the first direction and does not constitute a limitation of the first direction of the present application. For the convenience of description, the first direction is described as the x direction.

[0044] In the embodiment of the present application, the opening shape of the evaporation opening 11 is a polygon tangent to the pixel opening. Figure 4 The octagon shown in (a) can also be Figure 5 The octagon shown in (a) Figure 6 The dodecagon shown in (a) in .

[0045] The following describes in detail the opening shape design of the evaporation opening 11 of the mask plate 10 according to the embodiment of the present application with reference to the accompanying drawings.

[0046] In the prior art, the opening shape of the evaporation opening 11 is as follows: Figure 4As shown in (b) in the figure, the opening shape of the evaporation opening 11 is based on a rectangle, and two adjacent straight line segments in the rectangle are connected by an arc segment to prevent the opening surface of the evaporation opening 11 from having a right-angle shape (the shape of the evaporation opening 11 is the same as the shape of the display area. When the display area has a right-angled sharp angle, the display screen will appear jagged, affecting the display effect). However, through scanning electron microscopy observation, it was found that the evaporation shadow formed in the arc segment area of ​​the evaporation opening 11 is larger, while the evaporation shadow formed in the straight segment area of ​​the evaporation opening 11 is smaller.

[0047] Similarly, in the prior art, the opening shape of the evaporation opening 11 is also as follows Figure 5 (b) and Figure 6 As shown in (b), the opening shape of the evaporation opening 11 is connected by an arc segment between two adjacent straight line segments. This shape of the evaporation opening 11 will make the evaporation shadow during evaporation larger, reduce the distance between adjacent pixels, and cause color mixing between adjacent pixels, affecting the display effect of the display device.

[0048] Therefore, in the mask plate 10 provided in the embodiment of the present application, the opening shape of the evaporation opening 11 is designed to reduce the evaporation shadow during evaporation. Specifically, the arc segment portion of the evaporation opening 11 in the prior art is improved, such as Figure 4 As shown in (c), take the vertex of the arc segment as the tangent point and draw the external tangent of the arc segment ( Figure 4 The red line segment in (c) of FIG), the straight line segments at both ends of the arc segment are extended until they intersect with the circumtangent line of the arc segment, thereby forming a new octagon as the opening shape of the evaporation opening 11.

[0049] Similarly, if Figure 5 As shown in (c) in the figure, take the vertex of the arc segment between two adjacent straight line segments in the square as the tangent point and draw the external tangent line of the arc segment ( Figure 5 The red line segment in (c) of FIG), the straight line segments at both ends of the arc segment are extended until they intersect with the circumtangent line of the arc segment, thereby forming a new octagon as the opening shape of the evaporation opening 11.

[0050] In some embodiments, in an octagon, the angle between any two adjacent sides is 135°. Figure 4 (a) and Figure 5 In the octagon shown in (a), the angle α between any two adjacent sides is 135°.

[0051] It should be noted that in the octagon, the angle α between any two adjacent sides may also be other angles, and those skilled in the art may select an opening shape of the evaporation opening that matches the shape of the sub-pixels in the display area.

[0052] Similarly, if Figure 6 As shown in (c) in the figure, take the vertex of the arc segment between two adjacent straight line segments in the hexagon as the tangent point and draw the external tangent line of this arc segment ( Figure 6 The red line segment in (c) of FIG), the straight line segments at both ends of the arc segment are extended until they intersect with the circumtangent line of the arc segment, thereby forming a new dodecagon, which serves as the opening shape of the evaporation opening 11.

[0053] In some embodiments, in a dodecagon, the angle between any two adjacent sides is 150°. Figure 6 In the dodecagon shown in (a), the angle β between any two adjacent sides is 150°.

[0054] It should be noted that in the dodecagon, the angle β between any two adjacent sides may also be other angles, and those skilled in the art may select a matching opening shape of the evaporation opening according to the shape of the sub-pixels in the display area.

[0055] In an embodiment of the present application, the opening shape of the evaporation opening of the mask plate is designed. The opening shape is a polygon tangent to the pixel opening. The opening shape has straight edges and does not include arc edges, thereby reducing the shadow height of the mask plate. When the mask plate is used to evaporate the display substrate, the evaporation shadow can be reduced.

[0056] Therefore, by using the mask plate 10 provided in the embodiment of the present application to perform vapor deposition on the display substrate, the vapor deposition can be carried out smoothly, and the vapor deposition shadow can be reduced to avoid color mixing between adjacent pixels, thereby ensuring the display effect of the display device.

[0057] It should be understood that in the embodiments of the present application, Figure 2 The arrangement of the multiple evaporation openings 11 shown is for illustrative purposes only. The multiple evaporation openings 11 of the mask plate provided in the embodiment of the present application can also be arranged in other ways. Those skilled in the art can select a matching arrangement of the multiple evaporation openings based on the arrangement of the sub-pixels in the display area.

[0058] In some implementations, the arrangement of the plurality of evaporation openings 11 may be as follows: Figure 7 Arrangement shown.

[0059] In some implementations, the arrangement of the plurality of evaporation openings 11 may be as follows: Figure 8 Arrangement shown.

[0060] In some implementations, the arrangement of the plurality of evaporation openings 11 may be as follows: Figure 9 Arrangement shown.

[0061] It should be understood that when using the mask plate 10 to evaporate the display substrate, different mask plates 10 combinations with evaporation openings 11 with different opening shapes and multiple evaporation openings 11 with different arrangements can be selected to evaporate the display substrate according to the requirements of the arrangement of multiple sub-pixels in the display area, so as to form multiple sub-pixels with different arrangements.

[0062] For example, when multiple sub-pixels are arranged in a diamond pattern, Figure 2 The mask plate 10 shown is used to evaporate the display substrate to form a plurality of G pixels; Figure 2 The mask plate 10 shown, then select Figure 7 The mask plate 10 shown is used to evaporate the display substrate to form a plurality of B pixels; Figure 7 The mask plate 10 shown is evaporated to form a plurality of R pixels. After the above-mentioned evaporation, a plurality of RGB pixels arranged in a diamond pattern can be formed.

[0063] For example, you can also choose Figure 8 The mask plate 10 shown is used to perform multiple vapor deposition on the display substrate to form a plurality of RGB pixels respectively. The plurality of RGB pixels formed in this way are arranged in a blue diamond pattern.

[0064] For example, you can also choose Figure 9 The mask plate 10 shown is used to perform multiple vapor deposition on the display substrate to form a plurality of RGB pixels respectively. The plurality of RGB pixels formed in this way are arranged in a true RGB pattern.

[0065] In some embodiments, the polygonal shape of the evaporation opening 11 has at least two symmetry centers, and the two symmetry centers are perpendicular to each other.

[0066] In some embodiments, as Figure 3 As shown, the evaporation opening 11 includes a first opening portion 111 and a second opening portion 112. The first opening portion 111 and the second opening portion 112 are sequentially arranged and connected along the x direction. In the x direction, the size L1 of the first opening portion 111 is smaller than the size L2 of the second opening portion 112, and in the second direction, the size L3 of the first opening portion 111 is smaller than the size L4 of the second opening portion 112. The second direction is perpendicular to the x direction. For example, Figure 3 y direction shown.

[0067] It should be understood that the y direction is only an exemplary description of the second direction and does not constitute a limitation on the second direction of the present application. For the convenience of description, the second direction is described as the y direction.

[0068] In some implementations, when performing vapor deposition on the display substrate, the vapor deposition material passes through the first opening 111 and the second opening 112 in sequence.

[0069] In some implementations, such as Figure 3 As shown, the sidewall of the first opening 111 is a curved surface, and the sidewall of the second opening 112 is a curved surface.

[0070] In some implementations, such as Figure 3 As shown, the size of the first opening 111 in the y direction gradually decreases along the direction approaching the second opening 112 .

[0071] In some implementations, such as Figure 3 As shown, the size of the second opening 112 in the y direction gradually decreases as it approaches the first opening 111 .

[0072] In the embodiment of the present application, the first opening portion 111 and the second opening portion 112 of the evaporation opening 11 are designed with the above-mentioned shape and size to ensure a good evaporation effect when evaporating the display substrate, thereby ensuring the display performance of the display device.

[0073] In some implementations, a dimension L1 of the first opening 111 in the x-direction ranges from 1 μm to 4.5 μm.

[0074] It should be understood that the dimension L1 of the first opening 111 in the x-direction is the shadow height of the mask 10. In the embodiment of the present application, the shape of the evaporation openings 11 is designed to ensure that the shadow height corresponding to the evaporation openings 11 of the mask 10 is within an appropriate range, which is smaller than the shadow height corresponding to the curved area of ​​the evaporation openings 11 in the prior art. Therefore, using the mask provided in the embodiment of the present application for evaporation deposition can reduce the evaporation shadow, avoid color mixing between adjacent pixels, and thus ensure the display effect of the display device.

[0075] In some implementations, the evaporation opening 11 is formed by wet etching.

[0076] Wet etching is a technique of etching by immersing the etched material in an etching solution. Wet etching is isotropic, that is, the width of the lateral etching is close to the depth of the vertical etching. Therefore, the side walls of the first opening 111 and the second opening 112 of the evaporation opening 11 etched by wet etching are arc-shaped.

[0077] The embodiment of the present application also provides a method for designing a mask plate. Figure 10 FIG. 1 is a schematic flow chart of a mask design method 200 disclosed in an embodiment of the present application.

[0078] S201 , determining a first opening shape of an evaporation opening of a mask according to design parameters of a pixel opening of a display substrate.

[0079] Among them, the pixel opening includes multiple arc-shaped opening areas and a straight opening area between two adjacent arc-shaped opening areas, the first opening shape includes multiple straight edges and an arc-shaped line segment connecting any two adjacent straight edges among the multiple straight edges, the straight edges of the first opening shape correspond to the straight opening areas, and the arc-shaped line segments of the first opening shape correspond to the arc-shaped opening areas.

[0080] S202 , taking the vertex of the arc segment of the first opening shape as the tangent point, making an external tangent line of the arc segment, and extending the straight edge to intersect with the external tangent line of the arc segment to form a second opening shape.

[0081] The second opening is in the shape of a polygon tangent to the pixel opening.

[0082] S203 , determining the second opening shape as the opening shape of the evaporation opening.

[0083] The evaporation opening includes a reference area and a compensation area, the reference area corresponds to the arc-shaped opening area, and the compensation area corresponds to the straight-line opening area.

[0084] The specific shape of the second opening can refer to the above description. Figure 4 (a) Figure 5 (a) Figure 6 (a) in the above will not be described in detail here.

[0085] In an embodiment of the present application, the opening shape of the evaporation opening is designed using the above-mentioned design method, and a mask plate is prepared using the mask plate model formed by this design method. The mask plate is used to evaporate the display substrate, which can reduce the evaporation shadow and avoid color mixing between adjacent pixels, thereby ensuring the display effect of the display device.

[0086] The present application also provides a mask design device, such as Figure 11 As shown, the design device 300 includes a processor 301 and a memory 302, wherein the memory 302 is used to store computer programs, and the processor 301 is used to call the computer programs so that the device implements the design methods of the various embodiments of the present application.

[0087] An embodiment of the present application further provides a readable storage medium for storing a computer program, which, when executed by a computing device, enables the computing device to implement the methods of the various embodiments of the present application described above.

[0088] It is understood that the memory in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as SRAM, dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct RAM bus random access memory (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0089] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A mask plate, characterized in that: Used for evaporation deposition of display substrates, including: a plurality of evaporation openings arranged in an array, the evaporation openings including a reference area and a compensation area, the evaporation openings corresponding to pixel openings of the display substrate, the pixel openings including a plurality of arc-shaped opening areas and a linear opening area between two adjacent arc-shaped opening areas, the reference area corresponding to the arc-shaped opening area, the compensation area corresponding to the linear opening area, and the evaporation openings for allowing evaporation material to pass through; The evaporation opening extends along a first direction and penetrates the mask plate. The opening shape of the evaporation opening is a polygon formed by connecting an external tangent line tangent to a vertex of an arc-shaped line segment of the arc-shaped opening area and a straight line side of the straight line opening area. The first direction is a thickness direction of the mask plate. A buffer zone is used to block the evaporation material.

2. The mask according to claim 1, wherein: The polygon has at least two symmetry centers, and the two symmetry centers are perpendicular to each other.

3. The mask according to claim 1, wherein: The evaporation opening includes a first opening portion and a second opening portion, and the first opening portion and the second opening portion are arranged in sequence along the first direction and are connected. In the first direction, the size of the first opening portion is smaller than the size of the second opening portion, and in the second direction, the size of the first opening portion is smaller than the size of the second opening portion, and the second direction is perpendicular to the first direction.

4. The mask according to claim 3, wherein: When vapor deposition is performed on the display substrate, the vapor deposition material passes through the first opening and the second opening in sequence.

5. The mask according to claim 3, wherein: The side wall of the first opening is a curved surface, and the side wall of the second opening is a curved surface.

6. The mask according to any one of claims 3 to 5, characterized in that: Along a direction approaching the second opening, a size of the first opening in the second direction gradually decreases.

7. The mask according to any one of claims 3 to 5, characterized in that: Along a direction approaching the first opening, a size of the second opening in the second direction gradually decreases.

8. The mask according to any one of claims 3 to 5, characterized in that: The size of the first opening in the first direction ranges from 1 μm to 4.5 μm.

9. The mask according to any one of claims 3 to 5, characterized in that: The evaporation opening is formed by wet etching.

10. A method for designing a mask, characterized in that: The method comprises: Determining a first opening shape of an evaporation opening of a mask plate according to design parameters of a pixel opening of a display substrate; The pixel opening includes a plurality of arc-shaped opening areas and a linear opening area between two adjacent arc-shaped opening areas; the first opening shape includes a plurality of linear edges and an arc-shaped line segment connecting any two adjacent linear edges of the plurality of linear edges; the linear edges of the first opening shape correspond to the linear opening areas, and the arc-shaped line segments of the first opening shape correspond to the arc-shaped opening areas; Taking the vertex of the arc segment of the first opening shape as a tangent point, draw an external tangent line of the arc segment and extend the straight edge to intersect with the external tangent line of the arc segment to form a second opening shape, wherein the second opening shape is a polygon tangent to the pixel opening; determining the second opening shape as the opening shape of the evaporation opening; The evaporation opening includes a reference area and a compensation area, the reference area corresponds to the arc-shaped opening area, and the compensation area corresponds to the straight-line opening area.

Images