Preparation method of film layer structure, conductive film layer, display panel and display device

Abstract

The invention provides a preparation method of a film layer structure, a conductive film layer, a display panel and a display device.The preparation method comprises the steps that a substrate is provided, and a first metal layer is arranged on the substrate; arranging a protective layer on the first metal layer, wherein the protective layer extends out of the area of the first metal layer; wherein the protective layer is provided with a first part covering the first metal layer and a second part extending out of the first metal layer; etching the protective layer to expose at least part of the first metal layer; the protection layer on the first metal layer is thin, and the first part is etched before the second part is etched in the etching process, so that after the first metal layer is exposed, the structure around the first metal layer is still protected by the protection layer; the etching process can be completed without additionally arranging a mask layer, so that the processing efficiency can be improved, the processing cost can be reduced, and the processing property of a product can be improved.

Description

Technical Field

[0001] The present application belongs to the technical field of display devices, and in particular, relates to a method for preparing a film structure, a conductive film layer, a display panel, and a display device. Background Art

[0002] Active-matrix organic light emitting diode (AMOLED) and flat panel display devices based on light emitting diode (LED) technologies have been widely used in various consumer electronic products such as mobile phones, televisions, laptops, desktop computers, etc. due to their advantages such as high image quality, power saving, thin body and wide application range, becoming the mainstream in display devices.

[0003] However, the process performance of current AMOLED display products needs to be improved. Summary of the invention

[0004] The purpose of the present application is to provide a method for preparing a film layer structure, a conductive film layer, a display panel and a display device, aiming to solve the problem of low process performance of display products in traditional technologies.

[0005] A first aspect of an embodiment of the present application provides a method for preparing a film layer structure, the method comprising:

[0006] Providing a substrate, and disposing a first metal layer on the substrate;

[0007] A protective layer is provided on the first metal layer, and the protective layer extends out of the area of ​​the first metal layer; wherein the protective layer has a first portion covering the first metal layer and a second portion extending out of the first metal layer; and a thickness of the first portion is less than a thickness of the second portion;

[0008] The protection layer is etched to expose at least a portion of the first metal layer.

[0009] In some embodiments of the present application, providing a protective layer on the first metal layer includes:

[0010] The second portion is arranged to cover the side wall of the first metal layer.

[0011] In some embodiments of the present application, providing a first metal layer on the substrate includes:

[0012] A first sub-metal layer is provided on the substrate; the first sub-metal layer is a conductive layer;

[0013] A second sub-metal layer is disposed on the first sub-metal layer, and the second sub-metal layer is a structural strengthening layer; wherein a side wall of the second sub-metal layer is used to be covered by the second portion.

[0014] In some embodiments of the present application, the first sub-metal layer and the second portion form a first height difference in the thickness direction of the first metal layer, and the providing of a protective layer on the first metal layer includes:

[0015] The thickness of the first portion is set to be smaller than the first height difference.

[0016] In some embodiments of the present application, before providing the first sub-metal layer on the substrate, the method includes:

[0017] A third sub-metal layer is disposed on the substrate, and the first sub-metal layer is disposed on the third sub-metal layer; wherein the third sub-metal layer and the second sub-metal layer are made of the same material.

[0018] In some embodiments of the present application, the first sub-metal layer is made of aluminum material, and the second sub-metal layer and the third sub-metal layer are made of titanium material.

[0019] In some embodiments of the present application, providing a protective layer on the first metal layer, wherein the protective layer extends beyond the area of ​​the first metal layer, comprises:

[0020] The projection of the first metal layer on the substrate is set to fall within the projection of the protective layer on the substrate.

[0021] In some embodiments of the present application, before providing the first metal layer on the substrate, the method further includes:

[0022] A plurality of metal layers are arranged on the substrate, and a side of the plurality of metal layers facing away from the substrate is used for arranging the first metal layer.

[0023] In a second aspect, the present application also provides a conductive film layer, which is made using the above-mentioned preparation method.

[0024] In a third aspect, the present application also provides a display panel, which includes the above-mentioned conductive film layer.

[0025] In a fourth aspect, the present application also provides a display device, which includes the above-mentioned display panel.

[0026] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: the above-mentioned method for preparing a film layer structure, a conductive film layer, a display panel and a display device, the preparation method comprising: providing a substrate, setting a first metal layer on the substrate; setting a protective layer on the first metal layer, and the protective layer extending beyond the area of ​​the first metal layer; wherein the protective layer has a first part covering the first metal layer and a second part extending beyond the first metal layer; the thickness of the first part is less than the thickness of the second part; etching the protective layer to expose at least part of the first metal layer; in the present application, by setting the protective layer on the first metal layer to be thinner, the first part will be etched before the second part during the etching process, so after the first metal layer is exposed, the structure around the first metal layer is still under the protection of the protective layer; the etching process can be completed without adding a mask layer, which is beneficial to improving processing efficiency and reducing processing costs, and further beneficial to improving the process performance of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of the steps of a method for preparing a film layer structure provided in one embodiment of the present application;

[0028] Figure 2 A schematic diagram of the structure of a membrane layer provided in one embodiment of the present application;

[0029] Figure 3 A schematic diagram of the steps of a method for preparing a film layer structure provided in another embodiment of the present application;

[0030] Figure 4 A schematic structural diagram of a membrane layer structure provided in another embodiment of the present application;

[0031] Figure 5 A schematic structural diagram of a membrane layer structure provided in yet another embodiment of the present application;

[0032] Figure 6 A schematic structural diagram of a membrane layer structure provided in yet another embodiment of the present application.

[0033] Specific element symbol description: 100-substrate, 200-first metal layer, 210-first sub-metal layer, 220-second sub-metal layer, 230-third sub-metal layer, 300-protective layer, 310-first part, 320-second part, 400-multi-layer metal layer, 410-second metal layer, 420-third metal layer, 430-fourth metal layer. DETAILED DESCRIPTION

[0034] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0035] It should be noted that when an element is referred to as being "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0036] It should be understood that the terms "length", "width", "up", "down", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0037] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0038] It is important to know that with the continuous development of display technology, AMOLED display panels have been widely used in consumer electronic products such as smartphones, tablets, and wearable devices due to their excellent color expression, high contrast, low power consumption, and flexibility. The manufacturing process of AMOLED display panels involves complex film layer stacking and micro-processing technology, among which the design and production of the PAD area is particularly critical.

[0039] The PAD area is the electrical connection point between the AMOLED display panel and the external driver IC (integrated circuit). Its film layer structure usually adopts a multi-layer metal stack design to achieve good conductivity and mechanical stability. The top film layer usually adopts a combination of Ti (titanium) / Al (aluminum) / Ti (titanium) metal. This structure not only has excellent conductivity, but also provides good adhesion and corrosion resistance through the Ti layer. In actual production, the top metal needs to be completely exposed for electrical connection.

[0040] However, during the subsequent photolithography process, since the sides of the top metal are completely exposed, side etching will occur when the developer contacts these metal sides. Especially for AMOLED display panels with COE (Colorfilter On Encapsulation) structure, by integrating the color film or color filter into the encapsulation layer, although the integration and display effect of the display panel are effectively improved, it also increases the complexity of the process and the difficulty of protecting the PAD area.

[0041] After the top metal process is completed, the production process of COE products still needs to go through multiple photolithography processes. The developer used in these processes has a strong side-etching effect on the top metal. Long-term side-etching will not only cause the top metal to become thinner, but in severe cases, it will also cause the top metal to break or even peel off, thereby destroying the structural integrity of the PAD area, affecting its electrical connection with the external driver IC, and ultimately leading to a decline in the electrical performance and yield of the display panel.

[0042] Therefore, how to effectively prevent the side etching problem of the top metal in the subsequent photo process while maintaining good conductivity and connectivity in the PAD area has become a key technical problem in improving the manufacturing yield and performance of AMOLED display panels. Based on this, the present application improves the preparation method of the relevant film structure, the film structure, the display panel and the display device.

[0043] See also Figure 1 and Figure 2 , Figure 1 The schematic diagram of the steps of the method for preparing the membrane structure provided in this embodiment is shown. Figure 2 A schematic diagram of the structure of the membrane layer structure provided in this embodiment is shown. A method for preparing a membrane layer structure in this embodiment includes:

[0044] S100: providing a substrate 100, and disposing a first metal layer 200 on the substrate 100; specifically, the substrate 100 may be glass, plastic, ceramic or other materials suitable for manufacturing a display panel. It is understood that the first metal layer 200 may be directly formed on the substrate 100, or may be formed on the substrate 100 after forming other structures, and then forming the first metal layer 200 on the other structures.

[0045] S200: Disposing a protective layer 300 on the first metal layer 200, and the protective layer 300 extends out of the area of ​​the first metal layer 200; wherein the protective layer 300 has a first portion 310 covering the first metal layer 200 and a second portion 320 extending out of the first metal layer 200; the thickness of the first portion 310 is less than the thickness of the second portion 320;

[0046] Specifically, the protective layer 300 is used to protect the metal layer below from being etched or damaged during subsequent processing. The thickness difference between the first portion 310 and the second portion 320 is to perform selective etching during the etching process to avoid over-etching other structures outside the first metal layer 200 or over-etching the sidewall of the first metal layer 200.

[0047] S300: Etching the protective layer 300 to expose at least a portion of the first metal layer 200. Specifically, due to the thickness difference design of the protective layer 300, the etching process will first remove the thinner first portion 310, thereby exposing the underlying first metal layer 200. The etching process can be precisely controlled to ensure that only the required first metal layer 200 is exposed, while avoiding exposure of areas outside the upper surface of the first metal layer 200.

[0048] In the current method for preparing a film layer structure, an inorganic insulating layer is prepared on the top metal layer to protect the top metal layer. After the protection stage, a mask layer needs to be set on the inorganic insulating layer, and etching is performed on the mask layer to protect the structure outside the top metal layer while exposing the top metal layer. However, this will increase the cost by adding a mask layer, and the inorganic insulating layer on the top metal layer needs to be photoetched, resulting in reduced production capacity. However, in the present application, the protective layer 300 (first part 310) on the first metal layer 200 is relatively thin, and the first part 310 will be etched before the second part 320 during the etching process. Therefore, after the first metal layer 200 is exposed, the structure around the first metal layer 200 is still under the protection of the protective layer 300; the etching process can be completed without adding a mask layer, which is beneficial to improving processing efficiency and reducing processing costs, and thus is beneficial to improving the process performance of the product.

[0049] It is understandable that, in the process of etching the protective layer 300 , the Asher (Atomic Layer Etching) process can be directly used to etch the entire protective layer 300 without using a photolithography process, which is beneficial to improving the production capacity advantage.

[0050] In some embodiments of this application, please continue to refer to Figure 2 , step S200 of this embodiment includes: setting the second part 320 to cover the side wall of the first metal layer 200. Specifically, in the semiconductor manufacturing process, the side wall of the metal layer is often the part that is most susceptible to damage or contamination. By setting the second part 320 of the protective layer 300 on the side wall, the side wall can be effectively prevented from being chemically corroded, physically worn or contaminated in subsequent processes.

[0051] In some embodiments of this application, please refer to Figure 3 and Figure 4 , Figure 3The schematic diagram of the steps of the method for preparing the membrane structure provided in this embodiment is shown. Figure 4 The schematic diagram of the structure of the film layer structure provided in this embodiment is shown. Step S100 of this embodiment includes:

[0052] S110: a first sub-metal layer 210 is provided on the substrate 100; the first sub-metal layer 210 is a conductive layer; specifically, the conductive layer is mainly used to transmit current or signals. The conductive layer can be made of copper (Cu), aluminum (Al), gold (Au), etc.

[0053] S120: a second sub-metal layer 220 is disposed on the first sub-metal layer 210, wherein the second sub-metal layer 220 is a structural strengthening layer; wherein the sidewall of the second sub-metal layer 220 is used to be covered by the second portion 320. Specifically, the second sub-metal layer 220 has excellent adhesion to play a role in structural strengthening. The structural strengthening layer can be made of titanium (Ti) or the like.

[0054] In some embodiments of this application, please continue to refer to Figure 4 In this embodiment, the first sub-metal layer 210 and the second portion 320 form a first height difference in the thickness direction of the first metal layer 200 , and step S200 includes: setting the thickness of the first portion 310 to be smaller than the first height difference.

[0055] It should be explained that since the thickness of the first part 310 is smaller than the first height difference, after the first part 310 is etched, the first metal layer 200 will not be etched, and the first metal layer 200 will not be exposed, which is beneficial to improving the protection effect of the first metal layer 200.

[0056] In some embodiments of this application, please continue to refer to Figure 4 This embodiment includes, before step S110: disposing a third sub-metal layer 230 on the substrate 100, on which the first sub-metal layer 210 is disposed; wherein the third sub-metal layer 230 and the second sub-metal layer 220 are made of the same material.

[0057] In some embodiments, the third sub-metal layer 230 is also a structural strengthening layer. The third sub-metal layer 230 and the second sub-metal layer 220 are disposed on both sides of the first sub-metal layer 210 to improve the structural stability of the first sub-metal layer 210 .

[0058] In some embodiments of the present application, the first sub-metal layer 210 of the present embodiment is made of aluminum material, and the second sub-metal layer 220 and the third sub-metal layer 230 are made of titanium material.

[0059] In some embodiments of this application, please continue to refer to Figure 4, step S200 includes: setting the projection of the first metal layer 200 on the substrate 100 to fall within the projection of the protective layer 300 on the substrate 100 .

[0060] In some embodiments of this application, please refer to Figure 5 , Figure 5 The schematic diagram of the structure of the film layer structure provided in this embodiment is shown. Before step S100, this embodiment further includes: arranging a multi-layer metal layer 400 on the substrate 100, and the side of the multi-layer metal layer 400 facing away from the substrate 100 is used to arrange the first metal layer 200.

[0061] In some embodiments, please refer to Figure 5 Also see Figure 6 , Figure 6 The schematic structural diagram of the film layer structure provided in this embodiment is shown, and the multi-layer metal layer 400 includes a second metal layer 410, a third metal layer 420 and a fourth metal layer 430 arranged in sequence from bottom to top.

[0062] In some embodiments of this application, please refer to Figure 6 In the COE process, the first metal layer 200, especially the first metal sublayer, is prone to side etching, causing the second metal sublayer and / or the third metal sublayer to break or even peel off. In this embodiment, an OC HTM protective layer 300 is disposed on the first metal layer 200, and the protective layer 300 has a first portion 310 disposed on the first metal layer 200, and a second portion 320 disposed outside the first metal layer 200, wherein the thickness of the first portion 310 is less than the thickness of the second portion 320.

[0063] After the COE process, the Asher process is used to remove the thinner first part 310 above the first metal layer 200. For other areas that need to be covered by the protective layer 300, although the thickness of the second part 320 of the protective layer 300 is reduced, it does not affect its actual covering effect, thereby achieving the purpose of avoiding side engraving of the top metal layer.

[0064] Furthermore, in order to better implement the method for preparing the conductive film layer in any of the above embodiments, the present application also provides a conductive film layer based on the above preparation method, which is prepared by the above preparation method.

[0065] Furthermore, in order to better implement the conductive film layer in any of the above embodiments, based on the above pixel component, the present application also provides a display panel, which includes the above conductive film layer.

[0066] In some embodiments, the display panel may be an OLED display panel.

[0067] In a more specific embodiment, the display panel may be an AMOLED display panel. The conductive film layer in any of the above embodiments is a film layer structure in the Pad region of the AMOLED display panel.

[0068] Furthermore, in order to better implement the display panel in any of the above embodiments, based on the above display panel, the present application also provides a display device, which includes the above display panel.

[0069] In some embodiments, the display device may be a mobile phone, a tablet, a computer, etc.

[0070] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0071] The basic concepts have been described above. Obviously, for those skilled in the art, the above detailed disclosure is only for example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.

[0072] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0073] Similarly, it should be noted that in order to simplify the description of the disclosure of this application and thus help understand one or more embodiments of the invention, in the above description of the embodiments of this application, multiple features are sometimes combined into one embodiment, figure or description thereof. However, this disclosure method does not mean that the features required by the object of this application are more than the features mentioned in the claims. In fact, the features of the embodiments are less than all the features of the single embodiment disclosed above.

[0074] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for preparing a film structure, characterized in that: The preparation method comprises: Providing a substrate, and disposing a first metal layer on the substrate; A protective layer is provided on the first metal layer, and the protective layer extends out of the area of ​​the first metal layer; wherein the protective layer has a first portion covering the first metal layer and a second portion extending out of the first metal layer; The protection layer is etched to expose at least a portion of the first metal layer.

2. The preparation method according to claim 1, characterized in that: The step of providing a protective layer on the first metal layer comprises: The second portion is arranged to cover the side wall of the first metal layer.

3. The preparation method according to claim 2, characterized in that: The providing a first metal layer on the substrate comprises: A first sub-metal layer is provided on the substrate; the first sub-metal layer is a conductive layer; Disposing a second sub-metal layer on the first sub-metal layer, wherein the second sub-metal layer is a structural strengthening layer; wherein a side wall of the second sub-metal layer is used to be covered by the second portion; Preferably, the thickness of the first portion is smaller than the thickness of the second portion.

4. The preparation method according to claim 3, characterized in that: The first sub-metal layer and the second portion form a first height difference in the thickness direction of the first metal layer, and the providing of a protective layer on the first metal layer comprises: The thickness of the first portion is set to be smaller than the first height difference.

5. The preparation method according to claim 3, characterized in that: Before providing the first sub-metal layer on the substrate, the method includes: A third sub-metal layer is disposed on the substrate, and the first sub-metal layer is disposed on the third sub-metal layer; wherein the third sub-metal layer and the second sub-metal layer are made of the same material.

6. The preparation method according to claim 5, characterized in that: The first sub-metal layer is made of aluminum, and the second sub-metal layer and the third sub-metal layer are made of titanium.

7. The preparation method according to any one of claims 1 to 6, characterized in that: The step of providing a protective layer on the first metal layer, wherein the protective layer extends beyond the area of ​​the first metal layer, comprises: The projection of the first metal layer on the substrate is set to fall within the projection of the protective layer on the substrate.

8. The preparation method according to any one of claims 1 to 6, characterized in that: Before providing the first metal layer on the substrate, the method further includes: A plurality of metal layers are arranged on the substrate, and a side of the plurality of metal layers facing away from the substrate is used for arranging the first metal layer.

9. A conductive film layer, characterized in that: The invention is prepared by the preparation method according to any one of claims 1 to 8.

10. A display panel, characterized in that: The display panel comprises the conductive film layer according to any one of claims 9.

11. A display device, characterized in that: The display device comprises the display panel according to claim 10.

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