Half-tone mask, method for manufacturing display substrate, and display substrate

Abstract

The present invention provides a half-tone mask plate, the half-tone mask plate includes a metal shading pattern, the metal shading pattern includes a plurality of pattern parts, the metal shading pattern also includes an electrostatic discharge wire, at least one pair of adjacent pattern parts is connected with the electrostatic discharge wire, for at least one pair of pattern parts electrically connected by the electrostatic discharge wire, at least one of the pattern parts includes a pattern part body and a notch formed at the edge of the pattern part body, the end of the electrostatic discharge wire extends into the notch and is electrically connected to the pattern part body. Through the notch structure on the half-tone mask plate, the ESD risk of the half-tone mask plate itself can be reduced, and the burr effect on the metal pattern of the display substrate after exposure can be improved, and the ESD risk caused by burrs in the multi-layer overlap scene is also reduced. The present invention also provides a method for manufacturing a display substrate using the half-tone mask plate and a display substrate manufactured by the method.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a half-tone mask plate, a method for manufacturing a display substrate using the half-tone mask plate, and a display substrate manufactured by the manufacturing method. Background Art

[0002] Due to the increase in production capacity, the use rate of half-tone masks (HTM) in the display process of thin film transistor-liquid crystal display (TFT-LCD) is increasing. In order to achieve the product performance improvement of TFT-LCD, the design limit of the spacing of the array substrate row driver (GOA) is gradually decreasing. The mask used to produce the GOA unit will have a large number of metal traces on the periphery of the TFT-LCD display area. The line width is uneven, and tip discharge is prone to occur, resulting in electrostatic discharge (ESD). This electrostatic discharge will cause periodic defects in the display substrate of each TFT-LCD produced by this mask, reducing the product yield. Summary of the invention

[0003] Embodiments of the present invention provide a half-tone mask, a method for manufacturing a display substrate, and a display substrate.

[0004] As a first aspect of the present invention, an embodiment of the present invention provides a half-tone mask plate, wherein the half-tone mask plate includes a metal shading pattern, the metal shading pattern includes a plurality of graphic parts, the metal shading pattern also includes an electrostatic release wire, the electrostatic release wire is connected between at least one pair of adjacent graphic parts, and for at least one pair of graphic parts electrically connected by the electrostatic release wire, at least one of the graphic parts includes a graphic part body and a notch formed at the edge of the graphic part body, the end of the electrostatic release wire extends into the notch and is electrically connected to the graphic part body.

[0005] In some embodiments, the pattern portion includes a linear pattern portion for forming a metal trace and a block pattern portion for forming a metal block.

[0006] In some embodiments, the notch is a rectangular groove.

[0007] Furthermore, the size of the short side of the notch is between 1 μm and 2 μm.

[0008] Furthermore, the size of the long side of the notch is between 2.5 μm and 3.5 μm.

[0009] In some embodiments, the electrostatic release wire includes a first release wire and a second release wire, the graphic portion includes a first graphic portion and a second graphic portion, one end of the first release wire is electrically connected to the first graphic portion, the other end of the first release wire is electrically connected to one end of the second release wire, the other end of the second release wire is electrically connected to an adjacent second graphic portion, and the length direction of the first release wire intersects with the length direction of the second release wire.

[0010] In some embodiments, the length direction of the first release wire is perpendicular to the length direction of the second release wire.

[0011] In some embodiments, the width of the thinnest part of the electrostatic discharge wire does not exceed 1.0 μm.

[0012] As a second aspect of the present invention, an embodiment of the present invention provides a method for manufacturing a display substrate, comprising:

[0013] The metal pattern layer of the display substrate is patterned using the half-tone mask provided by the first aspect of the present invention to obtain the metal pattern layer.

[0014] As a third aspect of the present invention, an embodiment of the present invention provides a display panel, which includes a display substrate. The display substrate is manufactured by the manufacturing method of the display substrate provided by the second aspect of the present invention.

[0015] The halftone mask provided by the present invention proposes a mask structure setting suitable for producing GOA units to prevent electrostatic discharge, starting from the mask itself. By adding a unique structure of port compensation on the shading pattern of the mask, the mask reduces its own ESD risk while also reducing the impact of the design on the appearance of burrs in the metal pattern of the display substrate after exposure, thereby solving the problem that the existing mask is not mature enough in the structure related to preventing electrostatic discharge, and the appearance of burrs and other problems affect the performance of large-scale mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. The above and other features and advantages will become more apparent to those skilled in the art by describing detailed exemplary embodiments with reference to the accompanying drawings, in which:

[0017] Figure 1 A schematic structural diagram of a half-tone mask provided by an embodiment of the present invention;

[0018] Figure 2 is a schematic diagram of a half-tone mask in the related art, and the figure shows a location where ESD risk exists;

[0019] Figure 3 A schematic diagram of burrs on a metal layer of a display substrate made using a half-tone mask provided in the related art;

[0020] Figure 4 This is a schematic diagram of the ESD risk caused by burrs in the overlap scene between the gate layer and the source and drain layer when the display substrate is made by using the half-tone mask in the related art;

[0021] Figure 5 A schematic diagram of improving the effect of burrs when a half-tone mask is used to manufacture a display substrate provided by an embodiment of the present invention;

[0022] Figure 6 A partially enlarged schematic diagram of a notch and an electrostatic discharge wire on a half-tone mask provided by an embodiment of the present invention;

[0023] Figure 7 A partially enlarged schematic diagram of a port compensation structure on a half-tone mask provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to enable those skilled in the art to better understand the technical solution of the present invention, the half-tone mask, the manufacturing method of the display substrate and the display substrate provided by the present invention are described in detail below with reference to the accompanying drawings.

[0025] Example embodiments will be described more fully below with reference to the accompanying drawings, but the example embodiments may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. On the contrary, the purpose of providing these embodiments is to make the present invention thorough and complete and to enable those skilled in the art to fully understand the scope of the present invention.

[0026] In the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other.

[0027] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0028] The terms used herein are only used to describe specific embodiments and are not intended to limit the present invention. As used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms, unless the context clearly indicates otherwise. It will also be understood that when the terms "comprising" and / or "made of" are used in this specification, the presence of the features, wholes, steps, operations, elements and / or components is specified, but the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or groups thereof is not excluded.

[0029] The embodiments described herein may be described with reference to plan views and / or cross-sectional views by means of idealized schematic diagrams of the present invention. Therefore, the example illustrations may be modified according to manufacturing techniques and / or tolerances. Therefore, the embodiments are not limited to the embodiments shown in the drawings, but include modifications of the configurations formed based on the manufacturing process. Therefore, the regions illustrated in the drawings have schematic properties, and the shapes of the regions shown in the drawings illustrate the specific shapes of the regions of the elements, but are not intended to be limiting.

[0030] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and the present invention, and will not be interpreted as having an idealized or overly formal meaning unless explicitly defined as such herein.

[0031] As HTM is increasingly used in the TFT-LCD display process, the design limit of the GOA spacing is continuously reduced in order to improve the product performance of TFT-LCD. The mask used to produce the GOA unit will have a large number of metal traces around the TFT-LCD display area. The functions mainly involve modules such as GOA, fan-shaped and other resistor wiring areas, and the metal traces are uneven in thickness.

[0032] like Figure 2 As shown, the half-tone mask includes a pattern portion 11 for forming metal traces and metal blocks on the display substrate. Since the line width of the pattern portion 11 is uneven, the distance between the pattern portion 11 and its adjacent pattern portions 11 is also uneven. At some positions, the distance between the pattern portion 11 and the adjacent pattern portion 11 is large. However, at some positions, the distance between the pattern portion 11 and the adjacent pattern portion 11 is small. For example Figure 2 At the positions P1, P2, and P3 in the figure, the distance between the graphic portion 11 and the adjacent graphic portion 11 is quite small. Due to the static electricity accumulation during the production process of the half-tone mask plate manufacturer, if these positions are not processed in any way, tip discharge is likely to occur at these positions, causing electrostatic breakdown of the half-tone mask plate, resulting in defects in the graphics on the half-tone mask plate, and further causing periodic defects in each substrate produced by this half-tone mask plate. In the related art, in order to reduce the ESD risk, one way is to set a smaller width electrostatic release wire 13 between the graphic portion 11 and the adjacent graphic portion 11. One end of the electrostatic release wire 13 is electrically connected to the graphic portion 11, and the other end is electrically connected to the adjacent graphic portion 11.

[0033] In the production of products using half-tone mask technology, it is found that due to the low overall exposure of the half-tone mask, even if the half-tone mask itself does not cause ESD, the electrostatic discharge wire 13 will be incompletely exposed. During the development process, the port where the electrostatic discharge wire 13 is connected to the pattern portion 11 will remain due to the strong adhesion to the photoresist above the pattern portion 11. The middle electrostatic discharge wire 13 will be dissolved during the development process due to insufficient adhesion, so it will remain at the port of the pattern portion 11 to form a Figure 3 The tapered tip 15 (also called burr) shown in FIG. Figure 4 As shown, vias are formed between multiple layers, such as in Figure 4 At the positions marked 1 to 8, although the distance between the gate layer and the metal blocks on the source and drain layers and other metal blocks on their respective layers is not too close, after overlapping, the vertical distance between the metal blocks on different layers is small, and there will also be ESD risks.

[0034] In view of this, as one aspect of the present invention, a half-tone mask is provided, wherein Figure 1 As shown, the half-tone mask plate includes a metal shading pattern, the metal shading pattern includes a plurality of pattern parts 11, the metal shading pattern also includes an electrostatic release wire 13, at least one pair of adjacent pattern parts 11 is connected with the electrostatic release wire 13, for at least one pair of pattern parts 11 electrically connected by the electrostatic release wire 13, at least one of the pattern parts 11 includes a pattern part body and a notch 16 formed at the edge of the pattern part body, the end of the electrostatic release wire 13 extends into the notch 16 and is electrically connected to the pattern part body.

[0035] When the half-tone mask is used to perform a photolithography patterning process on a substrate having a metal layer, a positive photoresist needs to be coated on the metal layer to obtain a photoresist layer. Then, the photoresist layer is exposed using the half-tone mask as a mask. The portion of the photoresist layer that is not shielded by the metal light-shielding pattern is exposed and modified, while the portion shielded by the metal pattern is not exposed and modified.

[0036] As mentioned above, due to the low overall exposure of the half-tone mask, when the electrostatic release wire 13 is thin enough, the portion of the photoresist layer corresponding to the electrostatic release wire 13 is incompletely exposed. Finally, during the development process of the exposed photoresist layer, the portion corresponding to the electrostatic release wire 13 is dissolved.

[0037] In the present invention, the notch 16 provided at the connection port between the pattern portion 11 and the electrostatic discharge wire 13 can be regarded as a port compensation structure. After the notch 16 is provided, a notch corresponding to the notch 16 will be obtained on the metal pattern layer of the substrate. Even if burrs appear on the metal pattern layer of the substrate, the conical tip of the burr 15 will be moved back due to the corresponding notch. Specifically, Figure 5 As shown, since a notch corresponding to the notch 16 is also obtained on the metal pattern layer of the substrate, the generated burr 15 is located in the corresponding notch, and the tip of the burr 15 will not protrude too much, thus playing the role of eliminating the tip protrusion at least to a certain extent.

[0038] Optionally, the notch 16 may be provided only at the port where one end of the electrostatic discharge wire 13 is connected to the pattern portion 11 as port compensation.

[0039] Furthermore, notches 16 may be provided at both ends of the electrostatic discharge wire 13 at ports connected to different pattern portions 11 as port compensation.

[0040] Combine the following Figure 6 The notch 16 and the electrostatic discharge conductor 13 are described in detail. Figure 6 In the embodiment of the invention, the electrostatic discharge wire 13 includes a first discharge wire 131 and a second discharge wire 132. One end of the first discharge wire 131 is electrically connected to the graphic portion 11 on the right, and the other end is electrically connected to the second discharge wire 132. A notch 16 is provided at the connection between the first discharge wire 131 and the graphic portion 11 on the right as a port compensation. One end of the second discharge wire 132 is electrically connected to the graphic portion 11 on the left, and the other end of the second discharge wire 132 is electrically connected to the first discharge wire 131. Similarly, a notch 16 is also provided at the connection between the second discharge wire 132 and the graphic portion 11 on the left as a port compensation to smooth the burrs at the port.

[0041] In some embodiments, the pattern portion 11 of the half-tone mask includes a linear pattern portion for forming a metal trace and a block pattern portion for forming a metal block.

[0042] It should be noted that there is no particular limitation on the specific size and shape of the notch 16, as long as it can play the role of moving the tip back and eliminating burrs. For example, the notch can be a rectangular groove.

[0043] In some embodiments, the dimension of the notch 16 along the first direction (i.e., the length of the short side of the notch) is between 1 μm and 2 μm, the first direction is the direction extending from the edge of the graphic portion body to the interior of the graphic portion body, the dimension of the notch 16 along the second direction (i.e., the length of the long side of the notch) is between 2.5 μm and 3.5 μm, and the first direction is perpendicular to the second direction.

[0044] For example, Figure 7 As shown, the notch 16 is a rectangular groove, the size of the rectangular groove along the first direction Y is set between 1 μm and 2 μm, and the size of the rectangular groove along the second direction X is set between 2.5 μm and 3.5 μm.

[0045] In order to remove the portion of the metal layer corresponding to the electrostatic discharge conductor 13 after exposure and development, the width of the electrostatic discharge conductor can be set to no more than 1.0 μm. According to the current process level, the maximum line width that can be processed is about 0.8 μm. A preferred setting disclosed in the embodiment of the present invention is that the width of the electrostatic discharge conductor 13 is 0.8 μm, the size of the rectangular groove in the first direction is 1.5 μm, and the size in the second direction is 3 μm. Under this preferred size ratio, the burrs on the metal pattern of the display substrate made of the halftone mask can be effectively eliminated.

[0046] In some embodiments, the electrostatic discharge wire 13 is not a straight line, but a first discharge wire 131 and a second discharge wire 132 intersect at a certain angle. Usually, the first discharge wire 131 and the second discharge wire 132 are perpendicular to each other.

[0047] The electrostatic discharge conductor 13 is generally arranged between a pair of pattern parts 11 with a small distance. If a straight line is used, the distance between the tips of the burrs between two adjacent metal blocks or metal traces on the produced substrate will be smaller, which will increase the risk of tip discharge. Therefore, the first release conductor 131 and the second release conductor 132 intersecting at a certain angle can not only avoid the distance between the tips of the burrs between two adjacent metal blocks or metal traces being too small, but also make the thin wires neatly routed to avoid wiring congestion.

[0048] Since the HTM GOA unit is processed using a half-tone mask, the electrostatic discharge wire 13 is not completely exposed, making it easier for burrs to appear on the metal pattern of the display substrate produced. Therefore, in the process of processing the gate layer, the port compensation structure is set on the half-tone mask, which can not only reduce the ESD risk of the half-tone mask itself, but also improve the impact of burrs on the metal pattern of the display substrate after exposure, and also reduce the ESD risk caused by burrs in the overlap scene of the gate layer and the source and drain layer.

[0049] In a second aspect, an embodiment of the present invention provides a method for manufacturing a display substrate, wherein the method uses any one of the half-tone masks of the first aspect to pattern a metal layer of the display substrate to obtain a metal pattern layer.

[0050] When the half-tone mask is used to perform a photolithography patterning process on a substrate having a metal layer, a positive photoresist needs to be coated on the metal layer to obtain a photoresist layer. Then, the photoresist layer is exposed using the half-tone mask as a mask. The portion of the photoresist layer that is not shielded by the metal light-shielding pattern is exposed and modified, while the portion shielded by the metal pattern is not exposed and modified.

[0051] As mentioned above, due to the low overall exposure of the half-tone mask, when the electrostatic discharge wire 13 is thin enough, the portion of the photoresist layer corresponding to the electrostatic discharge wire 13 is not completely exposed. Finally, during the development process of the exposed photoresist layer, the portion corresponding to the electrostatic discharge wire 13 is dissolved. Since there may be residue at the port of the pattern portion 11, the metal layer of the corresponding substrate may be formed as follows: Figure 3 The burr 15 shown in the figure is provided with a notch 16 at the connection port between the graphic portion 11 of the half-tone mask plate and the electrostatic release wire 13. Since a notch corresponding to the notch 16 is also obtained on the metal graphic layer of the substrate, the generated burr 15 is located in the corresponding notch, and the tip of the burr 15 is not too protruding. Therefore, it can play the role of eliminating the tip protrusion at least to a certain extent.

[0052] In a third aspect, an embodiment of the present invention provides a display substrate, wherein the metal layer of the display substrate is manufactured by the method for manufacturing the display substrate according to the second aspect.

[0053] Because the port compensation structure is used on the halftone mask, the metal layer of the display substrate is patterned using this halftone mask, which can improve the effect of burrs on the metal pattern of the display substrate after exposure, and also reduce the ESD risk caused by burrs in the overlap scene between the gate layer and the source and drain layer. The specific details have been introduced in detail in the first aspect and will not be repeated here.

[0054] Example embodiments have been disclosed herein, and although specific terms are employed, they are used and should be interpreted only in a general illustrative sense and not for limiting purposes. In some instances, it will be apparent to those skilled in the art that, unless otherwise expressly noted, features, characteristics, and / or elements described in conjunction with a particular embodiment may be used alone or in combination with features, characteristics, and / or elements described in conjunction with other embodiments. Therefore, those skilled in the art will appreciate that various changes in form and detail may be made without departing from the scope of the invention as set forth in the appended claims.

Claims

1. A half-tone mask, comprising a metal shading pattern, the metal shading pattern comprising a plurality of pattern portions, the metal shading pattern further comprising an electrostatic discharge wire, at least one pair of adjacent pattern portions being connected to the electrostatic discharge wire, characterized in that: For at least one pair of graphic parts electrically connected by the electrostatic discharge wire, at least one of the graphic parts includes a graphic part body and a notch formed at an edge of the graphic part body, and an end of the electrostatic discharge wire extends into the notch and is electrically connected to the graphic part body; The notch is a rectangular groove; The size of the short side of the notch is between 1 μm and 2 μm; The size of the long side of the notch is between 2.5 μm and 3.5 μm; The width of the thinnest part of the electrostatic discharge wire does not exceed 1.0 μm; The electrostatic release wire includes a first release wire and a second release wire.

2. The half-tone mask according to claim 1, characterized in that: The pattern portion includes a linear pattern portion for forming a metal routing and a block pattern portion for forming a metal block.

3. The half-tone mask according to any one of claims 1 to 2, characterized in that: The graphic portion includes a first graphic portion and a second graphic portion, one end of the first release wire is electrically connected to the first graphic portion, the other end of the first release wire is electrically connected to one end of the second release wire, the other end of the second release wire is electrically connected to an adjacent second graphic portion, and the length direction of the first release wire intersects with the length direction of the second release wire.

4. The half-tone mask according to claim 3, characterized in that: The length direction of the first release wire is perpendicular to the length direction of the second release wire.

5. A method for manufacturing a display substrate, comprising: The metal pattern layer of the display substrate is patterned using the half-tone mask described in any one of claims 1 to 4.

6. A display substrate, characterized in that: The display substrate is manufactured by the method for manufacturing a display substrate according to claim 5.

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