Driving substrate, preparation method thereof, display panel and display device
By forming a patterned oxide protective layer on the first metal layer of the MLED backlight, the problem of anti-oxidation of the bonding area in the single-layer metal design is solved, simplifying the manufacturing process and reducing costs, while improving the performance and lifespan of the display device.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- TCL CHINA STAR OPTOELECTRONICS TECHNOLOGY CO LTD
- Filing Date
- 2023-09-21
- Publication Date
- 2026-07-31
AI Technical Summary
The single-layer metal design of MLED backlights cannot effectively prevent oxidation of the exposed copper bonding area, and it is difficult to prepare other film layers after electroplating thick copper, which affects the difficulty and cost of the manufacturing process.
A patterned oxide protective layer is formed on the first metal layer to cover the bonding area. The oxide protective layer is formed by chemical vapor deposition and photolithography. After electroplating thick copper, a second metal layer is formed on the outside, which simplifies the process and achieves the anti-oxidation effect.
It achieves effective anti-oxidation of the bonding area, simplifies the manufacturing process, reduces production costs, and improves the performance and lifespan of the display panel and display device.
Smart Images
Figure CN117518611B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of display technology, specifically to a driving substrate and its preparation method, a display panel, and a display device. Background Technology
[0002] Currently, products equipped with Mini-LED (MLED) backlighting, such as displays, automotive screens, tablets, and laptops, are attracting increasing attention from the industry. Compared to products with ordinary backlighting, MLED products have advantages such as wide color gamut, high contrast, and high brightness. In particular, MLED backlighting, through local dimming control, can achieve ultra-high contrast, truly achieving perfect black levels and avoiding light leakage or grayish appearance in dark areas. Among them, glass-based MLED backlighting has the advantages of large overall panel size, good heat dissipation, and high flatness, making it a hot research direction for mainstream manufacturers.
[0003] In related technologies, glass-based MLED backlights driven by microchips (Micro-ICs) simultaneously solder the IC and LEDs in-plane. Through active driving of the microchip, flicker-free active driving display is achieved in each zone. To ensure a reasonable layout of each signal line in-plane, and with a large line width and low voltage drop, cross-line connections are usually required between the LED and the IC. Therefore, two or more layers of metal traces must be used. However, double-layer traces are prone to reliability issues at the cross-line points, making them unsuitable for mass production.
[0004] Single-layer metal MLED backlighting is an emerging backlighting design solution. Compared to dual-layer or multi-layer backlighting designs, it not only offers better reliability but also lower costs and simpler manufacturing processes. However, single-layer solutions also have their drawbacks. The main drawback is that with only one layer of metal traces, it's impossible to apply surface anti-oxidation measures to exposed copper metal (such as bonding areas). Furthermore, after electroplating thick copper, it's complex to continue preparing other film layers on its surface. Summary of the Invention
[0005] The purpose of this application is to provide a driving substrate and its preparation method, a display panel and a display device. By forming an oxide protective layer on the first metal layer, an anti-oxidation effect is achieved at the position of the corresponding bonding area on the first metal layer, which facilitates the electroplating of thick copper and the subsequent preparation of other film layers, and reduces the process difficulty and production cost.
[0006] This application provides a method for fabricating a driving substrate, including:
[0007] Provide a substrate;
[0008] A first metal layer is formed on the surface of the substrate.
[0009] A patterned oxide protective layer is formed on the first metal layer at the location corresponding to the bonding area of the driving substrate;
[0010] A second metal layer is formed on the first metal layer in a region outside the oxide protective layer;
[0011] The oxide protective layer and the area covered by it on the first metal layer together constitute the bonding area.
[0012] Optionally, in some embodiments of this application, the step of forming a first metal layer on the surface of the substrate includes:
[0013] The first metal layer is formed on the substrate by physical vapor deposition.
[0014] Optionally, in some embodiments of this application, the step of forming a patterned oxide protective layer on the first metal layer at a location corresponding to the bonding area of the driving substrate includes:
[0015] The oxide protective layer is formed on the first metal layer by chemical vapor deposition;
[0016] A patterned area is formed on the oxide protective layer by photolithography, so that the oxide protective layer and the area covered by it on the first metal layer together form the bonding area.
[0017] Optionally, in some embodiments of this application, the step of forming a second metal layer on the first metal layer in a region outside the oxide protective layer includes:
[0018] A patterned electroplated photoresist is formed on the first metal layer using a photolithography process.
[0019] The first metal layer is electroplated, so that the area on the first metal layer not covered by the electroplated photoresist grows the second metal layer through electroplating.
[0020] Optionally, in some embodiments of this application, after the step of forming a second metal layer on the first metal layer in a region outside the oxide protective layer, the method further includes:
[0021] Photoresist stripping is performed on the driving substrate;
[0022] The first metal layer is etched to form a patterned circuit.
[0023] Optionally, in some embodiments of this application, the substrate is a rigid substrate or a flexible substrate.
[0024] Optionally, in some embodiments of this application, the material of the oxide protective layer includes at least one of indium tin oxide, indium zinc oxide, and indium gallium zinc oxide.
[0025] Accordingly, embodiments of this application also provide a driving substrate, including:
[0026] Substrate;
[0027] A first metal layer is disposed on the substrate; and
[0028] A second metal layer is disposed on the first metal layer;
[0029] In this embodiment, a patterned oxide protective layer is provided on the first metal layer at the position corresponding to the bonding area of the driving substrate, and the oxide protective layer and the area covered by it on the first metal layer together constitute the bonding area.
[0030] Accordingly, this application also provides a display panel including the aforementioned driving substrate.
[0031] Accordingly, this application also provides a display device, including the above-mentioned display panel, wherein the display device is any one of a monitor, a vehicle screen, a tablet computer, or a laptop computer.
[0032] The beneficial effects of the embodiments of this application are as follows:
[0033] This application provides a driving substrate and its preparation method, a display panel, and a display device. By forming a first metal layer on a substrate and forming a patterned oxide protective layer on the first metal layer at a position corresponding to the bonding area of the driving substrate, a driving substrate is prepared and applied to the display panel and display device. This not only provides anti-oxidation effect to the bonding area of the driving substrate, but also facilitates the electroplating of thick copper and the subsequent preparation of other film layers, which can indirectly simplify the process, help reduce production costs, and also help improve the performance of the corresponding display panel and display device and extend its service life. Attached Figure Description
[0034] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0035] Figure 1 This is a schematic flowchart of a method for fabricating a driving substrate according to an embodiment of this application;
[0036] Figure 2This is a schematic diagram of a method for fabricating a driving substrate according to an embodiment of this application;
[0037] Figure 3 This is a schematic diagram of the structure of a driving substrate provided in an embodiment of this application.
[0038] Explanation of reference numerals in the attached figures: 100, substrate; 200, first metal layer; 300, oxide protective layer; 400, second metal layer. Detailed Implementation
[0039] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. In addition, it should be understood that the specific embodiments described herein are only for illustration and explanation of this application and are not intended to limit this application. In this application, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in actual use or operation, specifically the drawing directions in the accompanying drawings; while "inner" and "outer" refer to the outline of the device.
[0040] In related technologies, glass-based MLED backlights driven by microchips (Micro-ICs) simultaneously solder the IC and LEDs in-plane. Through active driving of the microchip, flicker-free active driving display is achieved in each zone. To ensure a reasonable layout of each signal line in-plane, and with a large line width and low voltage drop, cross-line connections are usually required between the LED and the IC. Therefore, two or more layers of metal traces must be used. However, double-layer traces are prone to reliability issues at the cross-line points, making them unsuitable for mass production.
[0041] Single-layer metal MLED backlighting is an emerging backlighting design solution. Compared to dual-layer or multi-layer backlighting designs, it not only offers better reliability but also lower costs and simpler manufacturing processes. However, single-layer solutions also have their drawbacks. The main drawback is that with only one layer of metal traces, it's impossible to apply surface anti-oxidation measures to exposed copper metal (such as bonding areas). Furthermore, after electroplating thick copper, it's complex to continue preparing other film layers on its surface.
[0042] To address the above problems, this application provides a driving substrate and its fabrication method, a display panel, and a display device, which will be described in detail below. It should be noted that the order of description of the following embodiments is not intended to limit the preferred order of the embodiments.
[0043] Example 1
[0044] This embodiment provides a method for preparing a driving substrate. The prepared driving substrate can be applied to MLED backlight modules. It adopts a single-layer metal design and achieves an anti-oxidation effect on easily oxidized parts of the driving substrate.
[0045] Specifically, such as Figure 1 and Figure 2 As shown, the method for fabricating a driving substrate provided in this embodiment includes the following steps:
[0046] S1. Provide a substrate 100.
[0047] First, a substrate 100 is provided. The substrate 100 can be a rigid substrate, such as glass, or a flexible substrate. When the substrate 100 is a flexible substrate, it can include one, two, or more polyimide (PI) film layers, or it can be made of materials such as resin. The specific dimensions of the substrate 100 can be flexibly selected according to design requirements and are not specifically limited thereto.
[0048] In the actual fabrication process, to facilitate subsequent fabrication operations, after selecting the substrate 100, it can be decontaminated first. Specifically, cleaning the surface of the substrate 100 of dirt, oil, etc., can improve the adhesion between the substrate 100 and other film layers.
[0049] S2. A first metal layer 200 is formed on the surface of the substrate 100.
[0050] Specifically, a first metal layer 200 can be formed on the surface of the substrate 100 using physical vapor deposition (PVD). The first metal layer 200 can be made of copper, or other metals can be used depending on the design requirements. The dimensions of the first metal layer 200 on the substrate 100 can be flexibly selected according to design requirements, as long as it meets the requirements of the metal traces on the driving substrate, and there are no specific limitations on this.
[0051] S3. A patterned oxide protective layer 300 is formed on the first metal layer 200 at a position corresponding to the bonding area of the driving substrate.
[0052] In step S3, the position of the bonding area on the first metal layer 200 corresponding to the driving substrate can be determined according to design requirements. After determining the position of the bonding area on the first metal layer 200 corresponding to the driving substrate, a complete oxide protective layer 300 can be formed at the corresponding position on the first metal layer 200. Then, the oxide protective layer 300 can be patterned to form the required patterned oxide protective layer 300.
[0053] Specifically, a complete oxide protective layer 300 can be formed at the corresponding position of the first metal layer 200 by means such as chemical vapor deposition (CVD). Then, a patterned area can be formed on the oxide protective layer 300 by photolithography to obtain the desired patterned oxide protective layer 300.
[0054] In this embodiment, the main function of the oxide protective layer 300 is to prevent oxidation of the exposed metal parts on the driving substrate. Its material may include at least one of indium tin oxide (ITO), indium zinc oxide, and indium gallium zinc oxide, and there is no specific limitation on it.
[0055] After a complete oxide protective layer 300 is formed on the first metal layer 200, the process of forming a patterned area on the oxide protective layer 300 using photolithography is roughly as follows: a photosensitive material, such as photoresist, is coated on the oxide protective layer 300. Then, the photoresist is exposed and developed. The remaining photoresist protects the oxide protective layer 300. After etching and demolding, the desired patterned oxide protective layer 300 is obtained. It should be noted that the aforementioned photosensitive material can also be photoresist. The photoresist can be positive or negative. After exposure, the properties of the photosensitive portion of the positive photoresist change; after development, the exposed portion is removed. Exposure refers to irradiating the photoresist with light to make it photosensitive. Development refers to processing the exposed pattern to clearly display the pattern. After exposure, the properties of the photosensitive portion of the negative photoresist also change; after development, the exposed portion is retained.
[0056] It should be noted that in this embodiment, the oxide protective layer 300 is selected to be set at the bonding area on the driving substrate. However, in the actual preparation process, the oxide protective layer 300 can also be set at other parts that are prone to oxidation, such as the detection terminals of the driving substrate or the positive and negative terminals of the light-emitting diode. These parts are usually the locations where the driving substrate is electrically connected to the outside and are prone to oxidation.
[0057] Meanwhile, on the final manufactured drive substrate, the patterned oxide protective layer 300 and the area covered by it on the first metal layer 200 together constitute the bonding area. Thus, the oxide protective layer 300 completely covers the bonding area of the drive substrate, effectively preventing oxidation of the bonding area without affecting the performance and use of the drive substrate.
[0058] After completing the above processes, the method for fabricating a driving substrate provided in this embodiment further includes the following steps:
[0059] S4. A second metal layer 400 is formed on the first metal layer 200 in the region outside the oxide protective layer 300.
[0060] Specifically, a patterned electroplated photoresist can be first formed on the first metal layer 200 using a photolithography process. Then, the first metal layer 200 is electroplated, so that the area on the first metal layer 200 not covered by the electroplated photoresist is grown by electroplating to form the second metal layer 400.
[0061] It should be noted that when forming the electroplated photoresist on the first metal layer 200, the actual pattern of the electroplated photoresist can be determined according to the design requirements, and there is no specific limitation on it. The final pattern of the formed electroplated photoresist is to cover the circuitless area on the first metal layer 200 (i.e., the area on the first metal layer 200 without metal traces in the design). The specific process for forming the electroplated photoresist through photolithography can be referred to the formation process of the oxide protective layer 300 mentioned above, and will not be repeated here.
[0062] Meanwhile, the second metal layer 400 is formed by electroplating, and its specific material can be copper. To facilitate the subsequent formation of metal traces, the copper thickness of the electroplated second metal layer 400 can be greater than 3 μm, and the specific copper thickness can be flexibly selected as needed. For ease of description, in this embodiment, "thick copper" refers to a copper layer with a thickness greater than 3 μm.
[0063] When a thick copper layer is electroplated onto the first metal layer 200 to form the second metal layer 400, the oxide protective layer 300 is made of indium tin oxide (ITO), indium zinc oxide, or indium gallium zinc oxide. Since its material is quite different from the crystal structure of copper and there is a lattice mismatch, the electroplated copper will not be deposited on the oxide protective layer 300, and thus will not affect the oxide protective layer 300.
[0064] Following step S4, the following steps are also included:
[0065] S5. Perform photoresist stripping on the driving substrate; and
[0066] S6. Etch the first metal layer 200 to form a patterned circuit.
[0067] Specifically, after photoresist stripping is completed on the driving substrate, the first metal layer 200 is etched to form a patterned circuit, which constitutes the metal traces on the driving substrate.
[0068] It should be noted that since the oxide protective layer 300 is formed on the first metal layer 200 and not on the second metal layer 400, and the thick copper electroplating is carried out after the oxide protective layer 300 is formed, the oxide protective layer 300 does not need to be prepared on the second metal layer 400, which greatly reduces the difficulty of its manufacturing process.
[0069] In related technologies, electroplating thick copper usually requires cutting the panel into a smaller size, which cannot be adapted to large-size panels. Furthermore, it is more complicated to prepare other film layers after electroplating thick copper, making it difficult to prepare other anti-oxidation film layers on thick copper.
[0070] After completing the above fabrication process, micro-light-emitting diodes (MLEDs) and microchips (MicroICs) can be soldered onto the driving substrate according to design requirements. Specifically, these other steps are not the focus of this embodiment and are common knowledge in the field, therefore they will not be elaborated upon here.
[0071] Example 2
[0072] Please see Figure 3 This embodiment provides a driving substrate that can be applied to MLED backlight modules. It adopts a single-layer metal design, and the parts of the driving substrate that are prone to oxidation can achieve an anti-oxidation effect.
[0073] Specifically, the driving substrate includes a substrate 100, a first metal layer 200 disposed on the substrate 100, and a second metal layer 400 disposed on the first metal layer 200. A patterned oxide protective layer 300 is disposed on the first metal layer 200 at a position corresponding to the bonding area of the driving substrate. The oxide protective layer 300 and the area covered by it on the first metal layer 200 together constitute the bonding area.
[0074] In this embodiment, the substrate 100 can be a rigid substrate, such as glass, or a flexible substrate. When the substrate 100 is a flexible substrate, it can include one, two, or more polyimide (PI) film layers, or it can be made of materials such as resin. The specific dimensions of the substrate 100 can be flexibly selected according to design requirements and are not specifically limited thereto.
[0075] Meanwhile, the material of the first metal layer 200 can be copper, or other metals can be used according to design requirements. The size of the first metal layer 200 on the substrate 100 can be flexibly selected according to design requirements, as long as it can meet the requirements of metal traces on the driving substrate, without specific limitations.
[0076] Furthermore, the position of the bonding area on the first metal layer 200 corresponding to the driving substrate can be determined according to design requirements. After determining the position of the bonding area on the first metal layer 200 corresponding to the driving substrate, a complete oxide protective layer 300 can be formed on the corresponding position on the first metal layer 200, and then the oxide protective layer 300 can be patterned to form the required patterned oxide protective layer 300.
[0077] Specifically, a complete oxide protective layer 300 can be formed at the corresponding position of the first metal layer 200 by means such as chemical vapor deposition (CVD). Then, a patterned area can be formed on the oxide protective layer 300 by photolithography to obtain the desired patterned oxide protective layer 300.
[0078] In this embodiment, the main function of the oxide protective layer 300 is to prevent oxidation of the exposed metal parts on the driving substrate. Its material may include at least one of indium tin oxide (ITO), indium zinc oxide, and indium gallium zinc oxide, and there is no specific limitation on it.
[0079] It should be noted that in this embodiment, the oxide protective layer 300 is selected to be set at the bonding area on the driving substrate. However, in the actual preparation process, the oxide protective layer 300 can also be set at other parts that are prone to oxidation, such as the detection terminals of the driving substrate or the positive and negative terminals of the light-emitting diode. These parts are usually the locations where the driving substrate is electrically connected to the outside and are prone to oxidation.
[0080] On the final manufactured drive substrate, the patterned oxide protective layer 300 and the area covered by it on the first metal layer 200 together constitute the bonding area. Thus, the oxide protective layer 300 completely covers the bonding area of the drive substrate, effectively preventing oxidation of the bonding area without affecting the performance and use of the drive substrate.
[0081] When forming the second metal layer 400 on the first metal layer 200, a patterned electroplated photoresist can be first formed on the first metal layer 200 through a photolithography process. Then, the first metal layer 200 is electroplated so that the area on the first metal layer 200 not covered by the electroplated photoresist is grown with thick copper through electroplating to form the aforementioned second metal layer 400.
[0082] It should be noted that when forming the electroplated photoresist on the first metal layer 200, the actual pattern of the electroplated photoresist can be determined according to the design requirements, and there is no specific limitation on it. The final pattern of the formed electroplated photoresist is to cover the wireless area on the first metal layer 200 (i.e., the area on the first metal layer 200 without metal traces in the design).
[0083] After forming the second metal layer 400, photoresist is stripped from the driving substrate, and then the first metal layer 200 is etched to form a patterned circuit, which constitutes the metal traces on the driving substrate. Furthermore, components such as micro-light-emitting diodes (MLEDs) and microchips (MicroICs) (not shown in the figure) can be soldered onto the driving substrate.
[0084] It should be noted that since the oxide protective layer 300 is formed on the first metal layer 200 and not on the second metal layer 400, and the thick copper electroplating is carried out after the oxide protective layer 300 is formed, the oxide protective layer 300 does not need to be prepared on the second metal layer 400, which greatly reduces the difficulty of its manufacturing process.
[0085] In related technologies, electroplating thick copper usually requires cutting the panel into a smaller size, which cannot be adapted to large-size panels. Furthermore, it is more complicated to prepare other film layers after electroplating thick copper, making it difficult to prepare other anti-oxidation film layers on thick copper.
[0086] Example 3
[0087] This embodiment provides a display panel including the aforementioned driving substrate. The driving substrate comprises a bonding area formed by an oxide protective layer 300 and an area on the first metal layer 200 covered by the oxide protective layer 300. The oxide protective layer 300 provides an anti-oxidation effect to the bonding area without affecting its performance. This display panel can be a display panel equipped with MLED backlighting.
[0088] Example 4
[0089] This embodiment provides a display device including the aforementioned display panel. An oxide protective layer 300 on the driving substrate provides oxidation protection for exposed portions such as the bonding area. Specifically, this display device can be any of the following: a monitor with MLED backlighting, an automotive screen, a tablet computer, or a laptop computer.
[0090] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.
[0091] The foregoing has provided a detailed description of a driving substrate and its preparation method, display panel, and display device provided in the embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.
Claims
1. A method for driving the production of a substrate, characterized by, include: Provide a substrate; A first metal layer is formed on the surface of the substrate. A patterned oxide protective layer is formed on the first metal layer at the location corresponding to the bonding area of the driving substrate; A second metal layer is formed on the first metal layer in a region outside the oxide protective layer. The second metal layer is formed by electroplating. The crystal lattice of the material of the oxide protective layer is mismatched with that of the material of the second metal layer, so the second metal layer will not be deposited on the oxide protective layer. The oxide protective layer and the area covered by it on the first metal layer together constitute the bonding area.
2. The production method of a driving substrate according to claim 1, wherein The step of forming a first metal layer on the surface of the substrate includes: The first metal layer is formed on the substrate by physical vapor deposition.
3. The production method of a driving substrate according to claim 1, wherein The step of forming a patterned oxide protective layer on the first metal layer at a location corresponding to the bonding area of the driving substrate includes: The oxide protective layer is formed on the first metal layer by chemical vapor deposition; A patterned area is formed on the oxide protective layer by photolithography, so that the oxide protective layer and the area covered by it on the first metal layer together form the bonding area.
4. The production method of a driving substrate according to claim 1, wherein The step of forming a second metal layer on the first metal layer in a region outside the oxide protective layer includes: A patterned electroplated photoresist is formed on the first metal layer using a photolithography process. The first metal layer is electroplated, so that the area on the first metal layer not covered by the electroplated photoresist grows to form the second metal layer through electroplating.
5. The production method of a driving substrate according to claim 4, wherein After the step of forming a second metal layer on the first metal layer in the region outside the oxide protective layer, the method further includes: Photoresist stripping is performed on the driving substrate; The first metal layer is etched to form a patterned circuit.
6. The production method of a driving substrate according to claim 1, wherein The substrate can be a rigid substrate or a flexible substrate.
7. The production method of a driving substrate according to claim 6, wherein The material of the oxide protective layer includes at least one of indium tin oxide, indium zinc oxide, and indium gallium zinc oxide.
8. A drive substrate, characterized by, include: Substrate; A first metal layer is disposed on the substrate. as well as A second metal layer is disposed on the first metal layer, and the second metal layer is formed by electroplating. In this embodiment, a patterned oxide protective layer is provided on the first metal layer at the position corresponding to the bonding area of the driving substrate. The lattice of the oxide protective layer is mismatched with the lattice of the second metal layer, so the second metal layer will not be deposited on the oxide protective layer. The oxide protective layer and the area covered by it on the first metal layer together constitute the bonding area.
9. A display panel, characterized by, Includes the driving substrate as described in claim 8.
10. A display device, characterized in that, It includes the display panel as described in claim 9, and the display device is any one of a monitor, a vehicle screen, a tablet computer, and a laptop computer.