Display module, preparation method of display module and display device

Abstract

Embodiments of the present application provide a display module, a preparation method of the display module and a display device, and relate to the technical field of display. The display module comprises a display substrate and a back film. The display substrate comprises a display area, a bending area and a binding area located on one side of the display area. The bending area is located between the display area and the binding area. The bending area is bent so that the binding area is located on the backlight side of the display substrate. The binding area comprises first binding pins and second binding pins. The first binding pins are located on the backlight side of the display substrate. The back film is arranged on the backlight side of the display substrate. The surface of the back film away from the display substrate comprises a fingerprint module area and a fingerprint module binding area. The fingerprint module binding area is arranged on the side of the fingerprint module area close to the binding area. The fingerprint module area is provided with a fingerprint identification module. The fingerprint module binding area is provided with fingerprint pins. The fingerprint pins are electrically connected with the fingerprint identification module. The fingerprint pins are bindingly connected with the first binding pins. The embodiments of the present application realize the integration of the display substrate and the fingerprint identification module, can simplify the preparation process of the display module, reduce the production cost, and improve the preparation efficiency and yield of the display module.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a display module, a method for preparing the display module, and a display device. Background Technology

[0002] With the development of display technology, fingerprint recognition technology, due to its uniqueness, stability, and convenience, has been widely used in various scenarios such as mobile phone unlocking and mobile payments, and has evolved into different types with technological iterations. Among them, under-display fingerprint recognition technology places the fingerprint sensor under the screen glass, eliminating the need for an additional fingerprint recognition window on the front of the screen, thereby increasing the screen-to-body ratio and bringing a better visual experience.

[0003] Among related technologies, ultrasonic fingerprint recognition technology can recognize fingerprints even when there are water stains or dirt on the surface of the finger due to the strong penetrating power of ultrasound. Therefore, ultrasonic fingerprint recognition technology has become a new direction for the development of under-display fingerprint recognition. Summary of the Invention

[0004] This application provides a display module that helps to improve the problems of complex and inefficient assembly processes of fingerprint recognition modules and display substrates in the prior art.

[0005] According to one aspect of this application, a display module is provided, the display module comprising:

[0006] The display substrate includes a display area and a bending area and a bonding area located on one side of the display area. The bending area is located between the display area and the bonding area. The bending area bends so that the bonding area is located on the backlight side of the display substrate. The bonding area includes a first bonding pin and a second bonding pin. The first bonding pin is located on the backlight side of the display substrate, and the second bonding pin is located on the side of the first bonding pin away from the bending area. The second bonding pin is electrically connected to the first bonding pin. The second bonding pin is configured to bond a circuit board on which a fingerprint module driver chip is provided.

[0007] A back film is disposed on the backlight side of the display substrate; the surface of the back film away from the display substrate includes a fingerprint module area and a fingerprint module bonding area, the fingerprint module bonding area is disposed on the side of the fingerprint module area close to the bonding area; the fingerprint module area is provided with a fingerprint recognition module; the fingerprint module bonding area is provided with a fingerprint pin, the fingerprint pin is electrically connected to the fingerprint recognition module, and the fingerprint pin is bonded to a first bonding pin.

[0008] In one possible implementation, the display substrate includes a substrate layer having an opening in the bonding region, wherein the orthographic projection of the first bonding pin on the plane of the substrate layer is at least partially located within the opening, so that the first bonding pin is exposed from the opening on the backlight side of the display substrate.

[0009] In one possible implementation, there are multiple first binding pins, which are arranged in an array in a first direction and a second direction. The first direction intersects with the second direction, and the display area, the bending area, and the binding area are arranged sequentially in the second direction.

[0010] There are multiple openings, which are spaced apart along a first direction. The orthogonal projection of a column of first bonding pins on the plane where the substrate layer is located is located within one opening.

[0011] In another possible implementation, the display module further includes a circuit board on which a fingerprint module driver chip and a fingerprint pad are disposed. The fingerprint module driver chip is electrically connected to the fingerprint pad, and the fingerprint pad is bonded to a second bonding pin.

[0012] In another possible implementation, the fingerprint recognition module described above includes:

[0013] The circuit structure layer, disposed on one side of the back film, includes a transistor layer and a receiver electrode layer, with the transistor layer located between the back film and the receiver electrode layer; the transistor layer includes multiple transistors, the receiver electrode layer is electrically connected to the drain of the transistors, and the fingerprint pin is electrically connected to the receiver electrode layer.

[0014] A piezoelectric layer is disposed on the side of the circuit structure layer away from the back film;

[0015] The emitting electrode layer is disposed on the side of the piezoelectric layer away from the back film.

[0016] In another possible implementation, the transistor layer may include a gate metal layer and a source / drain metal layer stacked together; the fingerprint pin is disposed on the same layer as the gate metal layer or the source / drain metal layer in the transistor layer.

[0017] In another possible implementation, the fingerprint recognition module also includes a blocking layer disposed between the back film and the transistor layer.

[0018] In another possible implementation, the display substrate includes: a substrate layer and a pixel driving layer disposed on the side of the substrate layer away from the back film; the pixel driving layer is located in the display area and includes at least one gate metal layer and at least one source / drain metal layer;

[0019] The second binding pin is set on the same layer as the source and drain metal layers of the pixel driver layer;

[0020] The display substrate includes a bonding metal layer disposed on the side of at least one source / drain metal layer of the pixel driving layer near the substrate layer. The bonding metal layer includes a first bonding pin and a first trace electrically connected to the first bonding pin. The first trace is electrically connected to a second bonding pin through a via.

[0021] In another possible implementation, the display module further includes a heat dissipation layer disposed on the side of the back film away from the display substrate. A groove is provided on the side of the heat dissipation layer near the back film, in a direction perpendicular to the back film. The depth of the groove is less than the thickness of the heat dissipation layer, and the fingerprint recognition module is disposed in the groove.

[0022] In another possible implementation, the depth of the aforementioned groove is equal to the thickness of the fingerprint recognition module.

[0023] According to another aspect of this application, a display device is provided, including the display module shown in the first aspect of this application. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of a fingerprint recognition module provided in an embodiment of this application;

[0026] Figure 2 This application provides a schematic diagram of an OLED module structure with a fingerprint recognition module.

[0027] Figure 3 This is a schematic diagram of the structure of a display module provided in an embodiment of this application;

[0028] Figure 4 This is a schematic diagram of the light-emitting side of a display substrate in a display module provided in an embodiment of this application;

[0029] Figure 5 This is a schematic diagram of a backsheet structure in a display module provided in an embodiment of this application;

[0030] Figure 6 This is a schematic diagram of the backlight side structure in a display module provided in an embodiment of this application;

[0031] Figure 7 This is a schematic diagram of the structure of another display module provided in an embodiment of this application;

[0032] Figure 8 This is a schematic diagram of the backlight side of the substrate layer of a display substrate provided in an embodiment of this application;

[0033] Figure 9 A schematic diagram illustrating the bonding between a display module and a circuit board, provided in an embodiment of this application;

[0034] Figure 10 This is a schematic diagram of the structure of a display module after bending, provided in an embodiment of this application;

[0035] Figure 11 A cross-sectional view of a display module before bending, provided in an embodiment of this application;

[0036] Figure 12 A cross-sectional view of a display module after bending, provided in an embodiment of this application;

[0037] Figure 13 A cross-sectional structural diagram of a display substrate provided in an embodiment of this application;

[0038] Figure 14 A schematic flowchart illustrating a method for manufacturing a display module according to an embodiment of this application;

[0039] Figures 15-1 to 15-4 This is a schematic diagram of the structure in the manufacturing process of a display module provided in an embodiment of this application;

[0040] Figures 16-1 to 16-5 This is a schematic diagram of the structure in the preparation process of an ultrasonic sensing membrane provided in an embodiment of this application. Detailed Implementation

[0041] Embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0042] The accompanying drawings illustrate various structural schematics according to embodiments of the present disclosure. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0043] In the context of this disclosure, when a layer / element is referred to as being "above" another layer / element, the layer / element may be directly above the other layer / element, or there may be an intermediate layer / element between them. Additionally, if a layer / element is "above" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "below" the other layer / element.

[0044] The "co-layer configuration of A and B" described in this article refers to the simultaneous formation of A and B through the same patterning process. For example, the formation process may include: first forming at least one film layer using the same film deposition process, and then performing the same patterning process on these at least one film layer to form a layer structure containing a specific pattern. Depending on the specific pattern, the patterning process may include multiple coating, exposure, development, or etching processes, and the specific pattern in the formed layer structure may be continuous or discontinuous, and these specific patterns may also be at different heights (or thicknesses).

[0045] In recent years, with the widespread adoption of full-screen smartphones, under-display fingerprint technology has replaced traditional front-facing capacitive fingerprint recognition, providing a higher screen-to-body ratio for mobile phones and other terminal devices, and offering users a better display experience. Under-display fingerprint recognition technology has become the mainstream fingerprint recognition solution. The main categories of under-display fingerprint recognition technology are optical fingerprint recognition and ultrasonic fingerprint recognition. Optical fingerprint recognition requires a screen transmittance greater than 1.5%. However, due to the development and widespread adoption of LTPO (Low Temperature Polysilicon Oxide) screens and COE (Clor filter On Encapsulation) technology, screen transmittance is decreasing, making it unsuitable for optical fingerprint recognition. Therefore, ultrasonic fingerprint recognition has become a new direction for development.

[0046] In related technologies, an externally purchased ultrasonic fingerprint recognition module is bonded to the backlight surface of an OLED (Organic Light-Emitting Diode) module after opening a window in the heat dissipation layer. For example... Figure 1 The commercially available ultrasonic fingerprint recognition module includes a fingerprint recognition substrate layer 111, a piezoelectric layer 112, a cathode layer 113, and an insulating layer 114 stacked together. The fingerprint recognition substrate layer 111 typically has a thickness of 90 μm to 110 μm and includes a substrate and a thin-film transistor layer formed on the substrate through processes such as exposure, development, and etching. The substrate is typically glass-based or silicon-based. The piezoelectric layer 112 typically uses PVDF (polyvinylidene fluoride) or other piezoelectric materials, formed by spin coating or coating processes, and has a thickness of 10 μm. The cathode layer 113 can be made of silver alloy material, formed by screen printing, and has a thickness of 20 μm to 30 μm. The insulating layer 114 can be made of materials such as OC (Organic Compound) or ink, formed by coating processes, and has a thickness of 10 μm to 20 μm.

[0047] The fingerprint recognition module and the OLED module are bonded together as follows: Figure 2As shown, the OLED module includes an OLED substrate 201, a heat dissipation layer 202, and a back film 204. The thickness of the ultrasonic fingerprint recognition module plus the thickness of the PSA (Pressure Sensitive Adhesive) layer 203 (typically 15μm) is generally greater than 150μm. The height of the assembled fingerprint recognition module is higher than the height of the heat dissipation layer 202. Furthermore, an ultrasonic fingerprint circuit board 105 needs to be fabricated. The ultrasonic fingerprint chip is printed onto the ultrasonic fingerprint circuit board 105. The ultrasonic fingerprint circuit board 105 is first bonded to the ultrasonic fingerprint module and then inserted into the OLED circuit board.

[0048] To ensure reliability, a dispensing process is required on the edges of the fingerprint recognition module. Because its thickness exceeds that of the heat dissipation layer on the OLED module's backlight, it forms a protrusion, which must be avoided during OLED module assembly with the overall device. Furthermore, the excessive thickness of the fingerprint recognition module makes it susceptible to external pressure, potentially causing or exacerbating defects in the module's printing process. Therefore, the assembly processes for purchased ultrasonic fingerprint recognition modules and OLED modules are cumbersome and complex. The application of ultrasonic fingerprint recognition modules reduces product yield and increases production costs.

[0049] Based on the aforementioned technical problems, some embodiments of this application provide a first bonding pin and a second bonding pin in the bonding area of ​​the display substrate. The first bonding pin and the second bonding pin are located on different surfaces of the display substrate. Then, a fingerprint module area and a fingerprint module bonding area are provided on the surface of the back film away from the display substrate, wherein the fingerprint module bonding area is located on the side of the fingerprint module area closer to the bonding area. The fingerprint recognition module in the fingerprint module area is electrically connected to the fingerprint pin in the fingerprint module bonding area. By configuring the fingerprint recognition module on the back film, the fingerprint pin can be bonded to the first bonding pin. At the same time, the first bonding pin and the second bonding pin are electrically connected. The second bonding pin can bond to a circuit board on which a fingerprint module driver chip is provided. This circuit board can be the circuit board of the display substrate. That is, the fingerprint module driver chip can be integrated into the circuit board of the display substrate, and the fingerprint recognition module and the fingerprint module driver chip can be electrically connected through the first bonding pin. The embodiments of this application realize the integration of the display substrate and the fingerprint recognition module, which can simplify the display module manufacturing process, reduce production costs, and improve the manufacturing efficiency and yield of the display module.

[0050] The technical solutions of this application and how they solve the aforementioned technical problems will be described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0051] This application provides a display module, such as... Figure 3 As shown, it includes a display substrate 301 and a back film 302, with the back film 302 disposed on the backlight side of the display substrate 301.

[0052] Among them, such as Figure 4 As shown, the display substrate includes a display area 401 and a bending area 402 and a bonding area 403 located on one side of the display area. The bending area 402 is located between the display area 401 and the bonding area 403, and the bonding area 403 includes a first bonding pin 404. Figure 4 The diagram shows a schematic of the light-emitting side of the display substrate 301. The first bonding pin 404 is located on the backlight side of the display substrate 301 and is not visible from the light-emitting side, so it is indicated by a dashed line. The display substrate 301 is a flexible display substrate, such as OLED, QLED, OLCD (Organic Liquid Crystal Display), MICRO-LED (Micro Light Emitting Diode Display), etc., and is not specifically limited in this embodiment.

[0053] Figure 5 This is a schematic diagram of the back membrane 302, as shown below. Figure 5 As shown, the surface of the back film 302 away from the display substrate 301 includes a fingerprint module area 501 and a fingerprint module bonding area 502; the fingerprint module area 501 is provided with a fingerprint recognition module 504; the fingerprint module bonding area 502 is provided with a fingerprint pin 503, and the fingerprint pin 503 is electrically connected to the fingerprint recognition module 504 through a second trace 505.

[0054] Figure 6 To illustrate the structure of the backlight side of the display module, see the diagram below. Figure 6 As shown, the fingerprint module binding area 502 is located on the side of the fingerprint module area 501 near the binding area 403, and the fingerprint pin 503 can be configured to bind the first binding pin 404.

[0055] like Figure 3 As shown, in some embodiments, the above-mentioned display module further includes a heat dissipation layer 303 disposed on the side of the back film 302 away from the display substrate 301. A groove 308 is provided on the side of the heat dissipation layer 303 near the back film 302. The depth h of the groove 308 is less than the thickness t of the heat dissipation layer 303 in a direction perpendicular to the back film 302. The fingerprint recognition module 504 is disposed in the groove 308.

[0056] In some embodiments, the heat dissipation layer 303 may be a super clean foam (SCF) composite film or SUS (stainless steel) material. The heat dissipation layer can buffer the stress acting on the display module and dissipate the heat generated by the display module during operation, thus providing a certain degree of protection for the display module.

[0057] This application provides a possible implementation method in which the depth of the groove 308 is approximately equal to the thickness of the fingerprint recognition module 504. It is understood that the above-mentioned approximately equal can be completely equal or approximately equal within the range of process error.

[0058] In this embodiment, the groove depth of the heat dissipation layer 303 is equal to the thickness of the fingerprint recognition module 504. This protects the fingerprint recognition module 504 within the heat dissipation layer 303, eliminating reliability risks and avoiding the need for adhesive application to the edges of the fingerprint recognition module 504 in existing technologies. This simplifies the display module manufacturing process and improves product yield and production efficiency. Furthermore, the reduced thickness of the fingerprint recognition module 504 decreases the distance between the module and the finger during recognition, effectively improving the accuracy of ultrasonic fingerprint recognition.

[0059] This application provides one possible implementation method, such as... Figure 3 As shown, the fingerprint recognition module 504 may include a circuit structure layer 304, a piezoelectric layer 305, an emitting electrode layer 306, and an insulating layer 307.

[0060] The circuit structure layer 304 can be disposed on one side of the back film 302.

[0061] According to embodiments of this application, such as Figure 7 As shown, the circuit structure layer 304 may include a transistor layer 3041 and a receiving electrode layer 3042, with the transistor layer 3041 located between the back film 302 and the receiving electrode layer 3042; optionally, the material forming the receiving electrode layer 3042 may include indium tin oxide (ITO).

[0062] In some embodiments, transistor layer 3041 may include a plurality of transistors arranged in an array. For example, transistor layer 3041 may include an active layer, a gate insulating layer, a gate metal layer, an interlayer insulating layer, and a source / drain metal layer sequentially stacked on back film 302, wherein the gate metal layer is configured to form at least the gate of a transistor, and the source / drain metal layer is configured to form at least the source and drain of a transistor. For example, fingerprint pin 503 may be disposed on the same layer as the gate metal layer or the source / drain metal layer in transistor layer 3041.

[0063] For example, in some embodiments, a fingerprint pin 503 can be formed on the side of the gate metal layer near the back film 302 by metal coating or patterning processes, and the fingerprint pin 503 can be electrically connected to the gate metal layer or the source / drain metal layer through vias.

[0064] The fingerprint pin 503 can be electrically connected to the receiving electrode layer 3042, which can be electrically connected to at least one of the gate, source, and drain of the transistor. For example, the circuit structure layer 304 may also include a planarization layer disposed between the source / drain metal layers and the receiving electrode layer 3042, and the drain of the transistor and the receiving electrode layer 3042 can be electrically connected through a via penetrating the planarization layer.

[0065] The piezoelectric layer 305 is disposed on the side of the circuit structure layer 304 away from the back film 302. The material forming the piezoelectric layer 305 can be PVDF (polyvinylidene difluoride) or other piezoelectric materials.

[0066] The emitter electrode layer 306 is disposed on the side of the piezoelectric layer 305 away from the back film 302, and the material forming the emitter electrode layer 306 may include silver (Ag).

[0067] An insulating layer 307 is disposed on the side of the emitting electrode layer 306 away from the back film 302. The material forming the insulating layer 307 may include insulating protective materials such as OC, so as to protect the emitting electrode layer 306.

[0068] This application provides one possible implementation method, such as... Figure 7 As shown, the fingerprint recognition module 504 may further include a blocking layer 309 disposed between the back film 302 and the transistor layer 3041; the blocking layer 309 can prevent electron leakage between different metal layers.

[0069] In this embodiment, transistor layer 3041 receives electrical signals emitted from the circuit board, processes and amplifies the signals, and transmits them to piezoelectric layer 305. Upon receiving the processed and amplified electrical signals from transistor layer 3041, piezoelectric layer 305, based on the inverse piezoelectric effect, converts the electrical signals into ultrasonic signals and emits them towards the light-emitting side of display substrate 301. These ultrasonic waves penetrate display substrate 301 and reach the finger surface. When the ultrasonic waves reach the finger surface, due to the uneven structure of the fingerprint ridges, the distances between the peaks and troughs and the display substrate differ: at the peaks, the ultrasonic waves travel a relatively short distance; at the troughs, the ultrasonic waves travel a relatively long distance. Therefore, the ultrasonic waves reflected from the fingerprint peaks and troughs have a time difference and a phase difference, and the reflected ultrasonic waves carry information about the fingerprint ridges. Upon receiving the reflected ultrasonic waves, piezoelectric layer 305, based on the direct piezoelectric effect, converts these ultrasonic signals into electrical signals. Transistor layer 3041 again plays a role, amplifying and preprocessing the weak electrical signal converted by piezoelectric layer 305 to improve signal quality and strength for subsequent processing. Finally, after receiving the amplified and preprocessed electrical signal from transistor layer 3041, the fingerprint chip performs digital processing and analysis. Fingerprint chips typically integrate complex algorithms and models that convert the received electrical signal into a fingerprint image and compare it with pre-stored fingerprint templates to determine if it matches, ultimately completing the fingerprint recognition process.

[0070] This application provides a possible implementation method in which the display substrate 301 may include a substrate layer, such as... Figure 8 The diagram shows a schematic of the backlight side of the substrate layer of the display substrate 301. The substrate layer may be provided with an opening 801 located in the bonding area 403. The orthographic projection of the first bonding pin 404 on the plane where the substrate layer is located is at least partially located in the opening 801, so that the first bonding pin 404 is exposed from the opening 801 on the backlight side of the display substrate.

[0071] This application provides one possible implementation method, such as... Figure 8 As shown, there can be multiple first binding pins 404. The multiple first binding pins 404 are arranged in an array in the first direction and the second direction. The first direction intersects the second direction. The display area 401, the bending area 402 and the binding area 403 are arranged in sequence in the second direction.

[0072] Specifically, there can be multiple openings 801, and the multiple openings 801 are arranged at intervals along the first direction. The orthogonal projection of a column of first bonding pins 404 parallel to the second direction onto the plane where the substrate layer is located is located within one opening 801.

[0073] In some implementations, with Figure 8For example, at each opening 801 on the backlight side of the display substrate, three first bonding pins 404 can be exposed.

[0074] In other embodiments, a plurality of openings 801 may be arranged at intervals along the second direction, and the orthogonal projection of a row of first bonding pins 404 parallel to the first direction onto the plane of the substrate may be located at one opening 801.

[0075] In some other embodiments, the opening 801 may have an array of first bonding pins 404 whose orthogonal projections on the plane of the substrate layer are located within the opening 801.

[0076] This application provides one possible implementation method, such as... Figure 9 As shown, this is a schematic diagram of the bonding between the display module and the circuit board. The bonding area 403 also includes a second bonding pin 901. The second bonding pin 901 is located on the side of the first bonding pin 404 away from the bending area 402. The second bonding pin 901 is electrically connected to the first bonding pin 404. The second bonding pin 901 is configured to bond the circuit board 902.

[0077] This application provides a possible implementation method. The display module further includes a circuit board 902. The circuit board 902 is provided with a fingerprint module driver chip 903 and a fingerprint pad. The fingerprint module driver chip 903 is electrically connected to the fingerprint pad, and the fingerprint pad is bonded to the second bonding pin 901.

[0078] This application provides a possible implementation in which the bending area 402 can be bent so that the bonding area 403 is located on the backlight side of the display substrate, and the fingerprint pin 503 is bonded to the first bonding pin 404.

[0079] like Figure 10 As shown, this is a schematic diagram of the structure of the display module after bending. The bonding area is bent to the backlight side of the display substrate, so that the fingerprint pin 503 and the first bonding pin 404 contact and bond on the backlight side of the display substrate. At the same time, the circuit board 902 is also bent to the backlight side of the display substrate.

[0080] like Figure 11 As shown, this is a cross-sectional view of the display module before bending. The fingerprint recognition module 504 is electrically connected to the fingerprint pin 503 through the second trace 505, and the first bonding pin 404 is electrically connected through the first trace 1102 and the second bonding pin 901.

[0081] like Figure 12As shown, this is a cross-sectional view of the display module after bending. The bonding area is bent to the backlight side of the display substrate, so that the fingerprint pin 503 and the first bonding pin 404 contact and bond on the backlight side of the display substrate. At the same time, the circuit board 902 is also bent to the backlight side of the display substrate.

[0082] This application provides a possible implementation in which the display substrate includes: a substrate layer and a pixel driving layer disposed on the side of the substrate layer away from the back film; the pixel driving layer is located in the display area and includes at least one gate metal layer and at least one source / drain metal layer.

[0083] In this embodiment, the second bonding pin may be disposed on the same layer as at least one of the gate metal layer and at least one of the source / drain metal layers in the pixel driving layer.

[0084] Figure 13 A schematic diagram of the structure of a display substrate according to some embodiments of this application is shown. For example... Figure 13 As shown, the pixel driving layer may include: a first active layer 241, a first gate dielectric layer 242, a first gate metal layer 243, a second gate dielectric layer 244, a second gate metal layer 245, a first interlayer insulating layer 246, a second buffer layer 247, a second active layer 248, a third gate dielectric layer 249, a third gate metal layer 251, a second interlayer insulating layer 252, a first source / drain metal layer 253, a passivation layer 254, a first planarization layer 255, a second source / drain metal layer 256, a second planarization layer 257, a third source / drain metal layer 258, and a third planarization layer 259. For example, the material of the first active layer 241 includes low-temperature polysilicon to form a low-temperature polysilicon transistor. The material of the second active layer 248 includes a metal oxide such as IGZO (Indium Gallium Zinc Oxide) to form an oxide transistor. The first gate metal layer 243 (Gate1), the second gate metal layer 245 (Gate2), and the third gate metal layer 251 (Gate3) can be configured to form the gate of each transistor of the pixel driving circuit, form a capacitor, and form a scan signal line; the first source-drain metal layer 253 (SD1) can be configured to form a data signal line and the source and drain of each transistor; the second source-drain metal layer 256 (SD2) can be configured to form a power signal line; and the third source-drain metal layer 258 (SD3) can be configured to form an anode connection portion of the light-emitting device, through which the pixel driving circuit can be electrically connected to the anode of the light-emitting device.

[0085] like Figure 13As shown, the display layer 10 may further include a second barrier layer 210, a bottom shield metal (BSM) 220, and a first buffer layer 230 disposed between the substrate layer 100 and the driving circuit layer. For example, the second barrier layer 210 may include a first sub-barrier layer 211 and a second sub-barrier layer 212, the bottom shield metal (BSM) 220 may be disposed between the first sub-barrier layer 211 and the second sub-barrier layer 212, and the first buffer layer 230 may be disposed between the second sub-barrier layer 212 and the first active layer 241. In some embodiments, the orthographic projection of the bottom shield metal (BSM) 220 onto the substrate layer 100 may cover the orthographic projection of the driving transistor in the pixel driving circuit onto the substrate layer 100, which is beneficial for shielding the influence of static electricity on the driving transistor and reducing the influence of external light incident from the substrate layer 100 side on the active layer of the driving transistor.

[0086] For example, in Figure 13 In a corresponding embodiment, the second bonding pin may be disposed on the same layer as at least one of the first gate metal layer 243, the second gate metal layer 245, the third gate metal layer 251, the first source / drain metal layer 253, the second source / drain metal layer 256, the third source / drain metal layer 258, and the metal shielding layer 220.

[0087] Alternatively, in other embodiments, the second bonding pin 901 may be disposed on the side of the passivation layer 254 away from the substrate layer 100, and may be fabricated by metal coating or patterning processes. The second bonding pin 901 may be electrically connected to at least one of the first gate metal layer 243, the second gate metal layer 245, the third gate metal layer 251, the first source / drain metal layer 253, the second source / drain metal layer 256, and the third source / drain metal layer 258 through a via.

[0088] like Figure 13 As shown, the substrate layer 100 may include a first flexible substrate layer 101, a second flexible substrate layer 103, and a first barrier layer 102 stacked between the first flexible substrate layer 101 and the second flexible substrate layer. The material of the flexible substrate layer may include, for example, a PI (Polyimide) substrate, a PET (Polyethylene Terephthalate) substrate, or a PEN (Polyethylene Naphthalate Dicarbonate) substrate.

[0089] The display substrate may further include a pixel defining layer 260 and a plurality of light-emitting devices 270. The pixel defining layer 260 is disposed on the side of the second insulating layer 130 away from the substrate layer 100. The pixel defining layer 260 has a plurality of pixel openings 261 spaced apart in the display area. The light-emitting devices 270 are disposed at the pixel openings 261, and the pixel openings 261 are configured to define the light-emitting area of ​​the light-emitting device 270. For example, one light-emitting device 270 may be disposed at one pixel opening 261. Figure 13 The pixel defining layer 260 is disposed on the side of the third planarization layer 259 away from the substrate layer 100.

[0090] For example, taking an OLED device as an example, along the direction away from the substrate layer 100, the light-emitting device 270 may include an anode layer 271, a light-emitting layer 272, and a cathode layer 273 stacked sequentially. The anode layer 271 is disposed between the pixel defining layer 260 and the driving circuit layer, and the anode layers 271 of two adjacent light-emitting devices 270 are spaced apart and insulated from each other. The anode layer 271 is electrically connected to the pixel driving circuit, and at least a portion of the anode layer 271 is exposed at the pixel opening 261. For example, the orthographic projection of the lower port of the pixel opening 261 (i.e., the opening 131 on the surface near the substrate layer 100) onto the substrate layer 100 is within the orthographic projection range of the anode layer 271 onto the substrate layer 100.

[0091] The light-emitting layer 272 is disposed on the side of the anode away from the substrate layer 100. For example, at least a portion of the light-emitting layer 272 is located within the pixel opening 261 of the corresponding sub-pixel, forming an electrical connection with the anode layer 271 of the corresponding light-emitting device 270. In some embodiments, the light-emitting layer 272 may include a light-emitting material layer (EML) and a functional material layer stacked on top of the light-emitting material layer. For example, the functional material layer may include one or more of a hole injection layer (HIL), a hole transport layer (HTL), an electron transport layer (ETL), and an electron injection layer (EIL), specifically configured according to actual needs, and this disclosure does not limit this.

[0092] A cathode layer 273 is stacked on the side of the light-emitting layer 272 away from the substrate layer 100. In some embodiments, the cathode layers 273 of adjacent light-emitting devices 270 can be interconnected, such as... Figure 13 The cathode layers 273 of each light-emitting device 270 are arranged as shown to facilitate access to the cathode voltage signal of each light-emitting device 270. In other embodiments, the cathode layers 273 of each light-emitting device 270 may also be spaced apart from each other and electrically connected to each other through additional conductive structures such as metal isolation pillars.

[0093] In some embodiments, the anode layer 271 can be a composite structure formed by sequentially stacking a transparent conductive oxide film, a metal film, and another transparent conductive oxide film. The transparent conductive oxide film is made of, for example, any one of ITO (Indium Tin Oxide) and IZO (Indium Zinc Oxide), and the metal film is made of, for example, any one or more of aluminum (Al), silver (Ag), titanium (Ti), and molybdenum (Mo). In other embodiments, the anode layer 271 can also be a single-layer structure, such as a single-layer structure made of any one of aluminum (Al), silver (Ag), titanium (Ti), and molybdenum (Mo).

[0094] In some embodiments, the cathode layer 273 can be any one of the following metals: lithium (Li), aluminum (Al), magnesium (Mg), and silver (Ag), or an alloy of any combination of these materials, such as a magnesium-silver alloy or an aluminum-lithium alloy. In some embodiments, the anode layer 271 can serve as a reflective electrode, and the cathode layer 273 is configured to partially transmit and partially reflect the light emitted by the light-emitting layer 272. By utilizing the microcavity effect, the light-emitting device 270 achieves a better color gamut and luminous efficiency.

[0095] like Figure 13 As shown, the display substrate also includes an encapsulation layer 280. The encapsulation layer 280 covers the plurality of light-emitting devices 270 to protect them from water and oxygen corrosion. For example, the encapsulation layer 280 may include a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer stacked together. For example, the first and second inorganic encapsulation layers may be made of inorganic insulating materials such as nitrides, oxides, nitrogen oxides, nitrates, carbides, or any combination thereof. The organic encapsulation layer may be made of organic insulating materials such as acrylic fibers, hexamethyldisiloxane, polyacrylates, polycarbonates, or polystyrene.

[0096] In some embodiments, the display substrate 10 may further include a touch structure layer 290 disposed on the side of the encapsulation layer away from the substrate layer 100 to facilitate touch functionality. For example, the touch structure layer 290 may be fabricated using FMLOC (Flexible Multilayer On Cell) technology, as detailed in related technologies. For example, the touch structure layer 290 may include a first touch metal layer, a second touch metal layer, and a touch insulating layer disposed between the first touch metal layer and the second touch metal layer. The orthographic projections of the first touch metal layer and the second touch metal layer onto the substrate layer 100 do not overlap with the orthographic projections of the pixel opening 261 onto the substrate layer 100. One of the first touch metal layer and the second touch metal layer is configured to provide a first touch electrode and a second touch electrode, while the other is configured to provide a bridging portion bridging the first touch electrode or the second touch electrode. The extending directions of the first touch electrode and the second touch electrode intersect each other, for example, they may be perpendicular to each other. Taking a first touch metal layer with bridging electrodes and a second touch metal layer with first and second touch electrodes as an example, the second touch electrode includes multiple electrode units. Two adjacent electrode units are disconnected at the position that crosses the first touch electrode, and a via is provided in the touch insulating layer, which is then bridged by the bridging electrodes provided in the first touch metal layer.

[0097] In some embodiments, the display substrate 10 may further include a protective layer 300 (also referred to as TOC) disposed on the side of the pixel defining layer 260 away from the substrate layer 100. For example, when the display substrate 10 includes a touch structure layer 290, the protective layer 300 may be disposed on the side of the touch structure layer 290 away from the substrate layer 100 to protect the display substrate 10 from water and oxygen corrosion in the air. For example, the protective layer 300 may cover the display area, the fan-out area, and the bending area (BEND), depending on the needs of the actual product.

[0098] The display substrate includes a bonding metal layer disposed on the side of at least one source / drain metal layer of the pixel driving layer near the substrate layer. The bonding metal layer includes a first bonding pin and a first trace electrically connected to the first bonding pin. The first trace is electrically connected to a second bonding pin through a via.

[0099] This embodiment of the application sets a first bonding pin in the bonding area of ​​the display substrate, and then sets a fingerprint module area and a fingerprint module bonding area on the surface of the back film away from the display substrate, wherein the fingerprint module bonding area is set on the side of the fingerprint module area close to the bonding area; the fingerprint module area is provided with a fingerprint recognition module; the fingerprint module bonding area is provided with fingerprint pins, and the fingerprint pins are electrically connected to the fingerprint recognition module; this embodiment of the application configures the fingerprint recognition module on the back film, and since the fingerprint pins are configured to bond to the first bonding pin, the fingerprint recognition module and the fingerprint module driving circuit can be electrically connected through the first bonding pin; this embodiment of the application realizes the integration of the display substrate and the fingerprint recognition module, which can simplify the display module manufacturing process, reduce production costs, and improve the manufacturing efficiency and yield of the display module.

[0100] This application provides a method for manufacturing a display module, applicable to the manufacturing of the display module shown in the first aspect of this application, such as... Figure 14 As shown, the method includes:

[0101] S101 provides a display substrate, the display substrate including: a display area and a bending area and a bonding area located on one side of the display area, the bending area being located between the display area and the bonding area, and the bonding area including a first bonding pin.

[0102] S102 provides a backing film.

[0103] S103, a fingerprint recognition module and a fingerprint pin are formed on the first side of the back film, and the second side of the back film is attached to the backlight side of the display substrate. The fingerprint pin is located on the side of the fingerprint recognition module near the bonding area. The fingerprint pin is electrically connected to the fingerprint recognition module and is configured to bond the first bonding pin.

[0104] This application provides a possible implementation method in which a fingerprint recognition module and fingerprint pins are formed on the first side of the back film, and the second side of the back film is bonded to the backlight side of the display substrate, which may include:

[0105] S201, attach the second side of the back film to the support substrate.

[0106] The aforementioned supporting substrate can be a glass substrate.

[0107] Specifically, such as Figure 15-1 As shown, the second side of the back film 601 is bonded to the glass substrate 603 using photosensitive adhesive 602.

[0108] S202, a circuit structure layer and fingerprint pins are formed on the first side of the back film.

[0109] The circuit structure layer includes a transistor layer and a receiver electrode layer.

[0110] Specifically, such as Figure 15-2 As shown, the circuit structure layer 604 is fabricated on the first side of the back film 601.

[0111] S203, the back film is separated from the support substrate, and the second side of the back film, on which the circuit structure layer and fingerprint pins are formed, is bonded to the backlight side of the display substrate.

[0112] Specifically, such as Figure 15-3 As shown, the back film 601 and the glass substrate 603 can be separated by a laser peeling process, and a protective film 605 can be bonded to both the top and bottom surfaces. Then, as... Figure 15-4 As shown, the second side of the back film 601, on which the circuit structure layer 604 is formed, is bonded to the backlight side of the display substrate 606.

[0113] S204 provides an ultrasonic sensing membrane, which includes a pressure-sensitive adhesive layer and a piezoelectric layer and an emission electrode layer sequentially stacked on the pressure-sensitive adhesive layer.

[0114] Specifically, such as Figure 16-1 As shown, using the first protective film 607 as a substrate, a PSA (pressure-sensitive adhesive) layer 608 is coated on the protective film; as Figure 16-2 As shown, the piezoelectric layer 609 is fabricated using spin coating or coating processes, and the thickness of the piezoelectric layer 609 can be 10 μm; then, as... Figure 16-3 As shown, an Ag electrode is fabricated using a screen printing process, serving as the emitter electrode layer 610. The thickness of the emitter electrode layer 610 can be between 20 μm and 30 μm, for example, 20 μm, 25 μm, or 30 μm; furthermore, as... Figure 16-4 As shown, an insulating layer 611 is fabricated using a coating process to protect the cathode. The thickness of the insulating layer 611 can be between 10 μm and 20 μm, for example, 10 μm, 12 μm, or 15 μm. Figure 16-5 As shown, a second protective film 612 is attached to the upper surface of the insulating layer.

[0115] S205, attach the ultrasonic sensing membrane to the side of the circuit structure layer away from the back membrane 302.

[0116] In this embodiment, the transistor layer of the fingerprint recognition module is integrated into the display substrate. The photomask used in the process can be reused in the production of other fingerprint recognition display modules, effectively reducing R&D and production costs. Simultaneously, integrating the transistor layer of the fingerprint recognition module into the display substrate reduces the need for bonding the fingerprint recognition module circuit board and the insertion process between the fingerprint recognition module circuit board and the display substrate circuit board in existing technologies, simplifying the module process flow and improving yield and production efficiency. Furthermore, the thickness of the fingerprint recognition module in this application is effectively reduced, requiring only a semi-open window for the heat dissipation layer of the display substrate, resulting in a flat back surface of the display substrate. This improves molding and avoids interference issues that could exacerbate defects in the film printing.

[0117] The method of this application embodiment can be applied to the preparation of the display module provided in this application embodiment. The implementation principle is similar. The steps in the method of each embodiment of this application correspond to the film layer structure in the display module of each embodiment of this application. For detailed functional description of each film layer structure of the method, please refer to the description of the corresponding display module shown above, which will not be repeated here.

[0118] This embodiment of the application sets a first bonding pin in the bonding area of ​​the display substrate, and then sets a fingerprint module area and a fingerprint module bonding area on the surface of the back film away from the display substrate, wherein the fingerprint module bonding area is set on the side of the fingerprint module area close to the bonding area; the fingerprint module area is provided with a fingerprint recognition module; the fingerprint module bonding area is provided with fingerprint pins, and the fingerprint pins are electrically connected to the fingerprint recognition module; this embodiment of the application configures the fingerprint recognition module on the back film, and since the fingerprint pins are configured to bond to the first bonding pin, the fingerprint recognition module and the fingerprint module driving circuit can be electrically connected through the first bonding pin; this embodiment of the application realizes the integration of the display substrate and the fingerprint recognition module, which can simplify the display module manufacturing process, reduce production costs, and improve the manufacturing efficiency and yield of the display module.

[0119] This application provides a display device, including the display module shown in the first aspect of this application. The display device may include electronic display devices with various application forms such as flat, foldable, and rollable displays, such as mobile phones and tablets, and may be applicable to various fields such as mobile communication, automotive, and medical. It is not specifically limited in this application.

[0120] The above description does not provide detailed technical specifications regarding the structure of each layer. However, those skilled in the art should understand that layers and regions of desired shapes can be formed using various technical means. Furthermore, to form the same structure, those skilled in the art can also design methods that are not entirely identical to those described above. Additionally, although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be advantageously combined.

[0121] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0122] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A display module, characterized in that, include: A display substrate includes a display area and a bending area and a bonding area located on one side of the display area. The bending area is located between the display area and the bonding area. The bending area is bent such that the bonding area is located on the backlight side of the display substrate. The bonding area includes a first bonding pin and a second bonding pin. The first bonding pin is located on the backlight side of the display substrate, and the second bonding pin is located on the side of the first bonding pin away from the bending area. The second bonding pin is electrically connected to the first bonding pin, and the second bonding pin is configured to bond a circuit board on which a fingerprint module driver chip is provided. A back film is disposed on the backlight side of the display substrate; the surface of the back film away from the display substrate includes a fingerprint module area and a fingerprint module bonding area, the fingerprint module bonding area being disposed on the side of the fingerprint module area closer to the bonding area; the fingerprint module area is provided with a fingerprint recognition module; the fingerprint module bonding area is provided with a fingerprint pin, the fingerprint pin being electrically connected to the fingerprint recognition module, and the fingerprint pin being bonded to the first bonding pin; The display substrate further includes a substrate layer, the substrate layer having an opening located in the bonding area, and the orthographic projection of the first bonding pin on the plane of the substrate layer being at least partially located within the opening, so that the first bonding pin is exposed from the opening on the backlight side of the display substrate; The fingerprint recognition module includes: A circuit structure layer, disposed on one side of the back film, includes a transistor layer and a receiving electrode layer, wherein the transistor layer is located between the back film and the receiving electrode layer; the transistor layer includes a plurality of transistors, the receiving electrode layer is electrically connected to the drain of the transistors, and the fingerprint pin is electrically connected to the receiving electrode layer; A piezoelectric layer is disposed on the side of the circuit structure layer away from the back film; An emission electrode layer is disposed on the side of the piezoelectric layer away from the back film.

2. The display module according to claim 1, characterized in that, There are multiple first binding pins, and the multiple first binding pins are arranged in an array in a first direction and a second direction. The first direction intersects the second direction, and the display area, the bending area and the binding area are arranged sequentially in the second direction. The opening is multiple, and the multiple openings are arranged at intervals along the first direction. The orthogonal projection of a column of the first bonding pins on the plane where the substrate layer is located is located within one of the openings.

3. The display module according to claim 1, characterized in that, The display module also includes a circuit board on which a fingerprint module driver chip and a fingerprint pad are disposed. The fingerprint module driver chip is electrically connected to the fingerprint pad, and the fingerprint pad is bonded to the second bonding pin.

4. The display module according to claim 1, characterized in that, The transistor layer includes a gate metal layer and a source / drain metal layer stacked together; the fingerprint pin is disposed on the same layer as the gate metal layer or the source / drain metal layer in the transistor layer.

5. The display module according to claim 4, characterized in that, The fingerprint recognition module also includes a blocking layer disposed between the back film and the transistor layer.

6. The display module according to claim 1, characterized in that, The display substrate includes: a substrate layer and a pixel driving layer disposed on the side of the substrate layer away from the back film; the pixel driving layer is located in the display area, and the pixel driving layer includes at least one gate metal layer and at least one source / drain metal layer; The second bonding pin is disposed on the same layer as the source and drain metal layers of the pixel driving layer; The display substrate includes a bonding metal layer disposed on the side of at least one source / drain metal layer of the pixel driving layer near the substrate layer. The bonding metal layer includes a first bonding pin and a first trace electrically connected to the first bonding pin. The first trace is electrically connected to the second bonding pin through a via.

7. The display module according to claim 1, characterized in that, Also includes: A heat dissipation layer is disposed on the side of the back film away from the display substrate. A groove is provided on the side of the heat dissipation layer near the back film along a direction perpendicular to the back film. The depth of the groove is less than the thickness of the heat dissipation layer. The fingerprint recognition module is disposed in the groove.

8. The display module according to claim 7, characterized in that, The depth of the groove is equal to the thickness of the fingerprint recognition module.

9. A display device, characterized in that, Includes the display module as described in any one of claims 1-8.

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