Array substrate, manufacturing method thereof and display panel

Abstract

The embodiment of the invention provides an array substrate and a manufacturing method thereof and a display panel, the array substrate comprises a black matrix layer, the black matrix layer is arranged close to a liquid crystal layer, the black matrix layer comprises a plurality of black matrixes arranged at intervals, each black matrix comprises a metal layer and a resin layer, the resin layer wraps the metal layer, and the thickness of the resin layer is smaller than that of the metal layer. The black matrix of the array substrate is composed of the metal layer and the resin layer, the thickness of the resin layer is smaller than that of the metal layer, the resin layer can fully react with the developing solution after exposure to be completely removed, and therefore the array substrate does not have dark spots. The metal layer is large in thickness and can play a shading role, and the resin layer wraps the metal layer, so that the light reflecting effect of the metal layer can be improved, the reflectivity can be reduced, the readability of the display panel comprising the array substrate at each visual angle is improved, and the appearance of the display panel is uniformly black.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to an array substrate and a manufacturing method thereof, and a display panel. Background Art

[0002] Ultra-high PPI (Per Pixel Index) VR LCD (Virtual Reality liquid-crystal display) products are becoming more and more popular among consumers. However, as PPI increases, Pattern Pitch (pixel size) decreases dramatically, and more and more problems are also in front of developers. Especially in the production of the black matrix layer, because the PPI increases and the pixel opening becomes smaller, the resin black matrix cannot be completely removed at some locations after exposure, resulting in black matrix residues, causing dark spots in the product and seriously affecting the display effect. Although the metal black matrix can solve the problem of resin black matrix residues, it has the problem of high reflectivity. Summary of the invention

[0003] The purpose of the embodiments of the present application is to provide an array substrate and a manufacturing method thereof and a display panel, which can solve the problem of easy residue of the resin black matrix and have a lower reflectivity. The specific technical solution is as follows:

[0004] According to a first aspect of the present application, an array substrate is provided, comprising a black matrix layer, wherein the black matrix layer is arranged close to a liquid crystal layer, the black matrix layer comprises a plurality of black matrices arranged at intervals, the black matrix comprises a metal layer and a resin layer, the resin layer wraps the metal layer, and the thickness of the resin layer is less than the thickness of the metal layer.

[0005] In addition, the array substrate provided in the first aspect of the present application may also have the following technical features:

[0006] In some embodiments, the thickness of the resin layer is less than or equal to 0.2 μm.

[0007] In some embodiments, the thickness of the metal layer is 1.2 μm-1.5 μm.

[0008] In some embodiments, the metal layer is made of a single metal or an alloy.

[0009] In some embodiments, the array substrate includes a color filter layer and a driving layer arranged on the side of the black matrix layer away from the liquid crystal layer, the driving layer includes a base substrate and a plurality of thin film transistors arranged on one side of the base substrate, and the thin film transistors include an active layer, a gate, and a source and a drain electrically connected to the active layer.

[0010] In some embodiments, the array substrate includes a common electrode layer and a pixel electrode, the common electrode layer is arranged on a side of the color filter layer close to the liquid crystal layer, a first passivation layer is arranged between the driving layer and the color filter layer, a flat layer is arranged between the color filter layer and the common electrode layer, and a second passivation layer is arranged between the common electrode layer and the black matrix layer; the second passivation layer is provided with a first via hole, and the first via hole penetrates the second passivation layer, the flat layer and the first passivation layer along the thickness direction of the array substrate, the first part of the pixel electrode is filled between the black matrix, and the second part of the pixel electrode is filled in the first via hole and is electrically connected to the drain.

[0011] In some embodiments, the intervals between the black matrices are greater than the diameter of the first via hole.

[0012] In some embodiments, the pixel electrode further includes a third portion, and the third portion is located on a surface of the resin layer close to the liquid crystal layer.

[0013] A second aspect of the present application provides a method for manufacturing an array substrate, which is used to manufacture the above array substrate, comprising the following steps:

[0014] An array substrate is provided, and a metal layer is prepared on a side of the array substrate close to the liquid crystal layer.

[0015] A resin layer is coated on a side of the metal layer close to the liquid crystal layer, the thickness of the resin layer is less than the thickness of the metal layer, and the resin layer and the metal layer together form a black matrix layer.

[0016] The resin layer is exposed and developed to form a patterned resin layer.

[0017] The metal layer not covered by the resin layer is wet-etched, and the metal layer is over-etched so that the orthographic projection of the metal layer on the array substrate is located within the orthographic projection of the resin layer on the array substrate.

[0018] The resin layer is baked so that the resin layer wraps the metal layer.

[0019] The third aspect of the present application provides a display panel, which includes the array substrate mentioned above, an opposing substrate arranged in a box with the array substrate, and a liquid crystal layer located in the box, the opposing substrate includes a cover plate, and the cover plate is bonded to the array substrate by optical glue.

[0020] Beneficial effects of the embodiments of the present application:

[0021] The array substrate and its manufacturing method and display panel provided by the embodiment of the present application, the black matrix of the array substrate is composed of two layers, a metal layer and a resin layer, and the thickness of the resin layer is less than the thickness of the metal layer. Compared with the black matrix formed by a single resin layer, the thickness of the resin layer can be greatly reduced, so the resin layer can fully react with the developer and be completely removed after exposure, and there will be no resin layer residue, so the array substrate will not have dark spots, thereby improving the display effect of the display panel formed by the array substrate. The metal layer has a large thickness and can play a light-shielding role, and the resin layer wraps the metal layer, which can improve the reflective effect of the metal layer and reduce the reflectivity. The array substrate can increase the readability of the display panel formed by the array substrate at various viewing angles, and can effectively maintain the entire display panel blended into the black frame to achieve appearance consistency.

[0022] Of course, implementing any product or method of the present application does not necessarily require achieving all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other embodiments can also be obtained based on these drawings.

[0024] Figure 1 A schematic diagram of the structure of a display panel provided in an embodiment of the present application;

[0025] Figure 2 for Figure 1 Schematic diagram of the climbing of the pixel electrode;

[0026] Figure 3 for Figure 1 A top view of the metal routing of the array substrate.

[0027] The reference numerals are as follows:

[0028] Array substrate 100; base substrate 101; buffer layer 102; shielding metal 103; thin film transistor 104; active layer 1041; gate 1042; gate insulating layer 1043; source 1044; drain 1045; interlayer dielectric layer 105; first passivation layer 106; color filter layer 107; flat layer 108; common electrode layer 109; second passivation layer 110; first via hole 110a; pixel electrode 111; first part 1111; second part 1112; third part 1113; opposite substrate 200; cover plate 201; optical glue 202; liquid crystal layer 300; black matrix layer 400; black matrix 401; metal layer 401a; resin layer 401b. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field based on the present application belong to the scope of protection of the present application.

[0030] In a first aspect, an embodiment of the present application provides an array substrate 100, such as Figure 1 As shown, the array substrate 100 includes a black matrix layer 400, which is arranged close to the liquid crystal layer 300. The black matrix layer 400 includes a plurality of black matrices 401 arranged at intervals. The black matrix 401 includes a metal layer 401a and a resin layer 401b. The resin layer 401b wraps the metal layer 401a, and the thickness of the resin layer 401b is less than the thickness of the metal layer 401a.

[0031] In this embodiment, the black matrix 401 is composed of two layers, namely, a metal layer 401a and a resin layer 401b, and the thickness of the resin layer 401b is less than that of the metal layer 401a. Compared with the black matrix 401 formed by a single resin layer 401b, the thickness of the resin layer 401b is greatly reduced, so the resin layer 401b can fully react with the developer and be completely removed after exposure, and no resin layer 401b will remain. Therefore, the array substrate 100 will not have dark spots, thereby improving the display effect of the display panel including the array substrate 100. The metal layer 401a has a large thickness and can play a light shielding role, and the resin layer 401b wraps the metal layer 401a, which can improve the light reflection effect of the metal layer 401a and reduce the reflectivity.

[0032] It should be noted that the black matrix layer 400 is disposed close to the liquid crystal layer 300 , and the black matrix layer 400 may be disposed in such a way that it adheres to the encapsulation layer of the liquid crystal layer 300 .

[0033] It can be understood that reducing the screen reflectivity can not only increase the readability of the display panel including the array substrate 100 at various viewing angles, but also effectively maintain the entire display panel blending into the black frame to achieve consistency in appearance.

[0034] In some embodiments, Figure 1 , Figure 2 As shown, the thickness of the resin layer 401b is less than or equal to 0.2 μm. For example, the thickness of the resin layer 401b may be 0.2 μm, 0.15 μm, 0.1 μm, etc.

[0035] The smaller the thickness of the resin layer 401 b is, the less resin needs to react with the developer, so it is easier for the reaction to be complete, and the problem of residual resin layer 401 b will not occur.

[0036] However, the thickness of the resin layer 401b also determines the shielding effect on the metal layer 401a. If the thickness of the resin layer 401b is reduced to less than 0.1 μm, incomplete shielding is likely to occur. Therefore, the thickness of the resin layer 401b is preferably 0.1 μm-0.2 μm.

[0037] In some embodiments, Figure 1 , Figure 2 As shown, the thickness of the metal layer 401a is 1.2 μm-1.5 μm. For example, the thickness of the metal layer 401a may be 1.2 μm, 1.25 μm, 1.3 μm, 1.35 μm, 1.4 μm, 1.45 μm, 1.5 μm, etc.

[0038] The thickness of the metal layer 401a is 1.2 μm-1.5 μm, which can ensure that OD (optical density)>4.0, and has a good light shielding effect. Optical density is absorbance (A). According to the Lambert-Beer law, A=-lgT, T is transmittance, T=I / I0, I is the light intensity passing through the absorption cell, and I0 is the light intensity irradiated on the absorption cell.

[0039] In some embodiments, the metal layer 401 a is made of a single metal or an alloy.

[0040] The metal element may be metal molybdenum, metal aluminum or metal copper, and the alloy may be molybdenum alloy, aluminum alloy or copper alloy. The metal layer 401a may also be a molybdenum-aluminum-molybdenum laminate, molybdenum-aluminum-copper laminate or the like.

[0041] In some embodiments, Figure 1 , Figure 2 As shown, the array substrate 100 includes a color filter layer 107 and a driving layer arranged on the side of the black matrix layer 400 away from the liquid crystal layer 300, the driving layer includes a base substrate 101 and a plurality of thin film transistors 104 arranged on one side of the base substrate 101, and the thin film transistor 104 includes an active layer 1041, a gate 1042, and a source 1044 and a drain 1045 electrically connected to the active layer 1041.

[0042] Specifically, the gate 1042 is insulated from the active layer 1041 by a gate insulating layer 1043 , an interlayer dielectric layer 105 is provided on the side of the gate 1042 away from the substrate 101 , and the source 1044 and the drain 1045 are electrically connected to the active layer 1041 through vias penetrating the interlayer dielectric layer 105 and the gate insulating layer 1043 .

[0043] The liquid crystal layer 300 preferably uses positive liquid crystal molecules, that is, liquid crystal molecules with positive dielectric anisotropy. In the initial state, the positive liquid crystal molecules in the liquid crystal layer 300 are aligned parallel to the counter substrate 200 and the array substrate 100, and the alignment direction of the positive liquid crystal molecules close to the counter substrate 200 is parallel or anti-parallel to the positive liquid crystal molecules close to the array substrate 100. Of course, in other embodiments, the liquid crystal layer 300 may also use negative liquid crystal molecules, and the negative liquid crystal molecules in the liquid crystal layer 300 may be aligned perpendicular to the counter substrate 200 and the array substrate 100, that is, similar to the alignment mode of the VA display mode.

[0044] like Figure 1 As shown, the color filter layer 107 includes a color resist layer arranged in an array, the color resist layer includes red (R), green (G), and blue (B) color resist materials, and correspondingly forms red (R), green (G), and blue (B) sub-pixels.

[0045] The black matrix layer 400 is located above the color filter layer 107. The black matrix layer 400 and the color filter layer 107 are divided into two layers and do not interfere with each other during production. The black matrix layer 400 is located above the color filter layer 107, which reduces the shielding range of the black matrix 401 on the outgoing light, can improve the light transmittance, and improve the brightness of the array substrate 100. The positive projection of the black matrix 401 on the color filter layer 107 separates the color resistance layer to prevent light crosstalk between adjacent pixels. The thin film transistor 104 of the driving layer is used to control the alignment of the liquid crystal layer 300.

[0046] The base substrate 101 may be a rigid substrate or a flexible substrate, such as glass, or a flexible substrate such as polyimide (PI). A buffer layer 102 is generally provided on one side of the base substrate 101, and the buffer layer 102 is conducive to improving the anti-scratch performance and bending resistance of the array substrate 100. The driving layer is provided on the side of the buffer layer 102 away from the base substrate 101, and a shielding metal 103 is also provided on the side of the buffer layer 102 close to the base substrate 101, which is used to shield light and prevent external light from irradiating the channel region of the active layer 1041, generating photogenerated carriers, and interfering with the normal operation of the thin film transistor 104.

[0047] In some embodiments, Figure 1-Figure 3 As shown, Figure 3 is a top view of the metal wiring of the array substrate 100, Figure 3The active layer 1041 is not shown, only to show the relative position relationship between the pixel electrode 111 and the black matrix 401. The array substrate 100 includes a common electrode layer 109 and a pixel electrode 111. The common electrode layer 109 is arranged on the side of the color filter layer 107 close to the liquid crystal layer 300. A first passivation layer 106 is arranged between the driving layer and the color filter layer 107. A flat layer 108 is arranged between the color filter layer 107 and the common electrode layer 109. A second passivation layer 110 is arranged between the common electrode layer 109 and the black matrix layer 400. The second passivation layer 110 is provided with a first via hole 110a. The first via hole 110a penetrates the second passivation layer 110, the flat layer 108 and the first passivation layer 106 along the thickness direction of the array substrate 100. The first part 1111 of the pixel electrode 111 is filled between the black matrix 401. The second part 1112 of the pixel electrode 111 is filled in the first via hole 110a and is electrically connected to the drain electrode 1045.

[0048] In this embodiment, if Figure 1 , Figure 2 As shown, the color filter layer 107 and the black matrix layer 400 are further separated by a flat layer 108, a common electrode layer 109, and a second passivation layer 110, which further increases the spacing between the color filter layer 107 and the black matrix layer 400, reduces the shielding range of the black matrix 401 on the outgoing light, and improves the light transmittance. The pixel electrode 111 is located above the common electrode, and the two are insulated by the second passivation layer 110. Preferably, the common electrode is a planar electrode arranged on the entire surface, and the pixel electrode 111 is a block electrode arranged in an entire block in each pixel unit or a slit electrode with multiple electrode strips to form a fringe field switching mode (Fringe Field Switching, FFS), such as Figure 3 As shown, the pixel electrode 111 is a slit electrode having a plurality of electrode strips.

[0049] The common electrode and the pixel electrode 111 may be made of transparent electrodes such as indium tin oxide (ITO) or indium zinc oxide (IGO).

[0050] In some embodiments, the intervals between the black matrices 401 are larger than the diameter of the first via holes 110 a .

[0051] In this embodiment, the intervals between the black matrices 401 are larger than the diameter of the first via hole 110a, so that the size of the pixel electrode 111 is increased, thereby improving the strength of the pixel electrode 111. On the other hand, the intervals between the black matrices 401, that is, the size of the opening area, are larger, which is beneficial to improving the aperture ratio of the array substrate 100, thereby improving the display effect of the array substrate 100.

[0052] Specifically, Figure 2As shown, the pixel electrode 111 further includes a third portion 1113 , and the third portion 1113 is located on a surface of the resin layer 401 b close to the liquid crystal layer 300 .

[0053] In this embodiment, the pixel electrode 111 has a climbing design, and the third part 1113 is located on the upper surface of the resin layer 401b. Since the interval between the black matrices 401 is larger than the first via hole 110a, the climbing of the pixel electrode 111 is divided into two stages. First, it climbs from the first via hole 110a to the interval between the black matrices 401, and then climbs from the interval between the black matrices 401 to the surface of the resin layer 401b. This can reduce the climbing height of the pixel electrode 111, thereby reducing the climbing difficulty of the pixel electrode 111 and improving the yield rate of the pixel electrode 111.

[0054] A second aspect of the present application provides a method for manufacturing an array substrate 100, which is used to manufacture the array substrate 100 described above, and includes the following steps:

[0055] S1: providing an array substrate 100 , and preparing a metal layer 401 a on a side of the array substrate 100 close to the liquid crystal layer 300 .

[0056] S2: coating a resin layer 401 b on a side of the metal layer 401 a close to the liquid crystal layer 300 . The thickness of the resin layer 401 b is smaller than that of the metal layer 401 a . The resin layer 401 b and the metal layer 401 a together form a black matrix layer 400 .

[0057] S3: The resin layer 401b is exposed and developed to form a patterned resin layer 401b.

[0058] S4: wet-etching the metal layer 401a not covered by the resin layer 401b, and over-etching the metal layer 401a, so that the orthographic projection of the metal layer 401a on the array substrate 100 is located within the orthographic projection of the resin layer 401b on the array substrate 100.

[0059] S5: Bake the resin layer 401b so that the resin layer 401b wraps the metal layer 401a.

[0060] In the present embodiment, the black matrix 401 is a composite black matrix 401 composed of two film layers, a metal layer 401a and a resin layer 401b, and the thickness of the resin layer 401b is less than that of the metal layer 401a. Compared with the black matrix 401 formed by a single resin layer 401b, the thickness of the resin layer 401b in the composite black matrix 401 is greatly reduced, so the resin layer 401b can fully react with the developer and be completely removed after exposure, and no resin layer 401b will remain. Therefore, the array substrate 100 will not have dark spots, and the display effect of the display panel including the array substrate 100 is improved. The metal layer 401a has a large thickness and can play a light shielding role, and the resin layer 401b wraps the metal layer 401a, which can improve the light reflection effect of the metal layer 401a and reduce the reflectivity.

[0061] In addition, during the etching process of the metal layer 401a, it is over-etched, that is, the formed metal layer 401a shrinks relative to the resin layer 401b, so that during the baking process of the black matrix 401 in step S5, the fluidity of the resin layer 401b is enhanced, and a good wrapping effect can be formed on the metal layer 401a. Since the outer surface of the metal layer 401a is wrapped by the resin layer 401b, the reflective effect of the metal layer 401a is improved and the reflectivity is reduced.

[0062] A third aspect of an embodiment of the present application provides a display panel, which includes the array substrate 100 described above, an opposing substrate 200 arranged in a box with the array substrate 100, and a liquid crystal layer 300 located in the box, wherein the opposing substrate 200 includes a cover plate 201, and the cover plate 201 is bonded to the array substrate 100 by optical glue 202.

[0063] In this embodiment, the liquid crystal layer 300 is encapsulated in a pair of boxes formed by the array substrate 100 and the counter substrate 200, the black matrix layer 400 is arranged to fit the encapsulation layer of the liquid crystal layer 300, the cover plate 201 can be a glass cover plate 201, and the cover plate 201 is bonded to the array substrate 100 through an optical adhesive 202. Specifically, the optical adhesive is arranged around the liquid crystal layer 300, and the cover plate 201 is bonded to the array substrate through the optical adhesive. The bonding does not need to destroy the integrity of the counter substrate 200 and the array substrate 100, and is simple and easy. The black matrix 401 of the array substrate 100 of the display panel adopts a composite structure formed by a resin layer 401b and a metal layer 401a, and the resin layer 401b wraps the metal layer 401a, and the thickness of the resin layer 401b is less than the thickness of the metal layer 401a, so that the display panel will not have a dark spot problem caused by the residue of the resin layer 401b, and has a lower reflectivity. Understandably, reducing the screen reflectivity can not only increase the readability of the product at all viewing angles, but also effectively maintain the entire display panel blending into the black frame, achieving a more beautiful appearance.

[0064] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0065] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0066] The above description is only a preferred embodiment of the present application and is not intended to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application are included in the protection scope of the present application.

Claims

1. An array substrate, characterized in that: The array substrate includes a black matrix layer, the black matrix layer is arranged close to the liquid crystal layer, the black matrix layer includes a plurality of black matrices arranged at intervals, the black matrix includes a metal layer and a resin layer, the resin layer wraps the metal layer, and the thickness of the resin layer is less than the thickness of the metal layer.

2. The array substrate according to claim 1, characterized in that: The thickness of the resin layer is less than or equal to 0.2 μm.

3. The array substrate according to claim 2, characterized in that: The thickness of the metal layer is 1.2 μm-1.5 μm.

4. The array substrate according to claim 1, characterized in that: The metal layer is made of a single metal or an alloy.

5. The array substrate according to any one of claims 1 to 4, characterized in that: The array substrate includes a color filter layer and a driving layer arranged on a side of the black matrix layer away from the liquid crystal layer. The driving layer includes a base substrate and a plurality of thin film transistors arranged on one side of the base substrate. The thin film transistors include an active layer, a gate, and a source and a drain electrically connected to the active layer.

6. The array substrate according to claim 5, characterized in that: The array substrate comprises a common electrode layer and a pixel electrode, the common electrode layer is arranged on a side of the color filter layer close to the liquid crystal layer, a first passivation layer is arranged between the driving layer and the color filter layer, a flat layer is arranged between the color filter layer and the common electrode layer, and a second passivation layer is arranged between the common electrode layer and the black matrix layer; The second passivation layer is provided with a first via hole, and the first via hole penetrates the second passivation layer, the planar layer and the first passivation layer along the thickness direction of the array substrate. The first part of the pixel electrode is filled between the black matrices, and the second part of the pixel electrode is filled in the first via hole and is electrically connected to the drain.

7. The array substrate according to claim 6, characterized in that: The interval between the black matrices is greater than the diameter of the first via hole.

8. The array substrate according to claim 7, characterized in that: The pixel electrode further includes a third portion, and the third portion is located on a surface of the resin layer close to the liquid crystal layer.

9. A method for manufacturing an array substrate, used for manufacturing the array substrate according to any one of claims 1 to 8, characterized in that: The following steps are involved: Providing an array substrate, and preparing a metal layer on a side of the array substrate close to the liquid crystal layer; A resin layer is coated on a side of the metal layer close to the liquid crystal layer, wherein the thickness of the resin layer is less than the thickness of the metal layer, and the resin layer and the metal layer together form a black matrix layer; exposing and developing the resin layer to form a patterned resin layer; Wet-etching the metal layer not covered by the resin layer, and over-etching the metal layer so that the orthographic projection of the metal layer on the array substrate is within the orthographic projection of the resin layer on the array substrate; The resin layer is baked so that the resin layer wraps the metal layer.

10. A display panel, characterized in that: The display panel includes an array substrate according to any one of claims 1 to 8, an opposing substrate arranged in a box with the array substrate, and a liquid crystal layer located in the box, wherein the opposing substrate includes a cover plate, and the cover plate is bonded to the array substrate by optical glue.

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