Silicon-based OLED display module, assembly method thereof, and display device

Abstract

The disclosed embodiment provides a silicon-based OLED display module and an assembly method thereof, as well as a display device including the silicon-based OLED display module. The assembly method includes providing a backplane with a frame and an opening structure on one side; attaching the silicon-based OLED display panel to the attachment area on the inner bottom surface of the backplane; wire bonding the silicon-based OLED display panel to the circuit board assembly in the binding area on the inner bottom surface of the backplane other than the attachment area; assembling a sealing strip at the opening structure of the backplane on the circuit board assembly; and attaching a light-shielding material above the backplane assembled with the sealing strip. The technical solution of the disclosed embodiment adopts a split rubber frame to realize the wire bonding process of the circuit board assembly, which can effectively protect the silicon-based substrate, enhance the heat dissipation performance of the device, improve the dimensional accuracy of the product, and prevent light leakage.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a silicon-based OLED display module and an assembly method thereof, and a display device. Background Art

[0002] Silicon-based organic light-emitting diode (OLED) is a new type of display device with silicon wafer as substrate. It has the advantages of self-luminescence, low power consumption, miniaturization and high PPI, and is widely used in AR / VR devices and medical equipment.

[0003] During the assembly process of silicon-based OLED display modules, conventional die bonding (DB) and wire bonding (WB) methods can easily cause scratches or edge collapse of the silicon wafer, which can bring the risk of a black screen, and the periphery of the AA area is prone to light leakage. In addition, the flexible printed circuit (FPC) is easily damaged by pulling during the bending process, and poor wire bonding can cause short circuits between pins, which can cause a black screen or display abnormalities. Summary of the invention

[0004] The embodiments of the present disclosure provide a method for assembling a silicon-based OLED display module to solve or alleviate one or more technical problems in the prior art.

[0005] As one aspect of an embodiment of the present disclosure, an embodiment of the present disclosure provides an assembly method of a silicon-based OLED display module, wherein the silicon-based OLED display module includes a silicon-based OLED display panel, a circuit board assembly, and a backplane, and the assembly method includes:

[0006] Providing a back panel having a frame and an opening structure on one side;

[0007] Attaching the silicon-based OLED display panel to the attachment area of ​​the inner bottom surface of the backplane;

[0008] Wire bonding the silicon-based OLED display panel to the circuit board assembly in a binding area other than the attachment area on the inner bottom surface of the backplane;

[0009] Assembling a sealing strip at the opening structure of the back plate on the circuit board assembly; and

[0010] A light shielding material is attached to the upper surface of the back plate assembled with the sealing strip.

[0011] In some possible implementations, the silicon-based OLED display panel is attached to the backplane via a first thermally conductive tape.

[0012] In some possible implementations, the sealing strip is bonded to the circuit board assembly by a second adhesive tape.

[0013] In some possible implementations, grooves are formed on the frames at both sides of the bottom plate opening structure, and the sealing strip is limited by the grooves.

[0014] In some possible implementations, the silicon-based OLED display panel is formed by forming a device layer on a silicon-based substrate, and disposing a cover glass on the device layer, and forming a step portion between the cover glass and the device layer.

[0015] The assembling method further comprises assembling a glue frame on the step portion to fill the space between the cover glass and the device layer.

[0016] In some possible implementations, the wire bonding includes attaching the silicon-based OLED display panel to an attachment area on the inner bottom surface of the backplane from one side of the opening structure.

[0017] In some possible implementations, the wire bonding includes connecting bonding pads on the silicon-based OLED display panel to bonding pads on the circuit board assembly.

[0018] In some possible implementations, the assembly method further includes attaching a third adhesive tape on the bottom edge of the opening structure of the back plate to prevent damage to the circuit board assembly.

[0019] As another aspect of the embodiments of the present disclosure, the embodiments of the present disclosure provide a silicon-based OLED display module, which is assembled by the above-mentioned assembly method.

[0020] As another aspect of the embodiments of the present disclosure, the embodiments of the present disclosure provide a silicon-based OLED display module, including a silicon-based OLED display panel, a circuit board assembly, and a backplane;

[0021] Wherein, the back plate has a frame and an opening structure on one side, and the inner bottom surface includes an attachment area and a binding area;

[0022] The silicon-based OLED display panel is thermally connected to the attachment area;

[0023] The silicon-based OLED display panel is wire-bonded to the circuit board assembly in the binding area;

[0024] The opening structure of the back plate is sealed by a sealing strip; and

[0025] The back plate is covered by a light shielding material.

[0026] As one aspect of an embodiment of the present disclosure, an embodiment of the present disclosure provides a display device, including the above-mentioned silicon-based OLED display module.

[0027] According to the silicon-based OLED display module in the embodiment of the present disclosure, a split rubber frame is used to implement the wire bonding process of the circuit board assembly, which can effectively protect the silicon-based substrate, enhance the heat dissipation performance of the device, improve the dimensional accuracy of the product, and prevent light leakage.

[0028] The above summary is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments and features described above, further aspects, embodiments and features of the present disclosure will be readily apparent by reference to the accompanying drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in accordance with the present disclosure and should not be regarded as limiting the scope of the present disclosure.

[0030] Figure 1 This is a schematic diagram of the exploded structure of a silicon-based OLED display module in one embodiment of the present disclosure;

[0031] Figure 2 This is a schematic diagram of a finished product of a silicon-based OLED display module in one embodiment of the present disclosure;

[0032] Figure 3 This is a schematic diagram of the structure of a backplane in an embodiment of the present disclosure;

[0033] Figure 4 The figure is a flow chart of a method for assembling a silicon-based OLED display module in one embodiment of the present disclosure.

[0034] Description of reference numerals:

[0035] 10. Backplane; 20. Silicon-based OLED display panel (chip); 21. Silicon wafer with device layer; 22. Cover glass; 30. FPC; 40. Glue frame; 50. Shading material; 60. Protective tape; 61. Thermal conductive tape; 62. Sealing tape; 63. Sealing strip; S1. Chip bonding; S2. FPC bonding; S3. Sealing strip assembly; S4. Glue frame assembly; S5. Shading material attachment. DETAILED DESCRIPTION

[0036] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present disclosure. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0037] Figure 1 Schematic diagram of the exploded structure of a silicon-based OLED display module in one embodiment of the present disclosure. Figure 2 This is a schematic diagram of the finished product of the silicon-based OLED display module. Figure 1 and Figure 2 As shown, the silicon-based OLED display module in the embodiment of the present disclosure includes a backplane 10, a flexible printed circuit board FPC 30, a silicon-based OLED display panel 20, a glue frame 40, a sealing strip 63 and a light shielding material 50 in sequence.

[0038] Specifically, Figure 3 As shown, the back plate 10 has frames on three sides and an opening structure on the other side to facilitate the FPC attachment process. According to one embodiment, the frames on both sides of the opening structure have grooves adjacent to the ends of the opening structure to limit the sealing strip 63.

[0039] According to an embodiment of the present disclosure, the back plate 10 has a metal-plastic integrated structure, that is, the back plate 10 has a bottom plate of metal material to facilitate the effective conduction of heat generated in the device, and a frame of plastic material (i.e., a plastic frame). The metal material that can be used here can be a metal with good thermal conductivity and light weight, such as aluminum or aluminum alloy, which is conducive to heat dissipation while increasing structural strength. The frame with an opening is made by injection molding, and the dimensional accuracy of the product is greatly improved.

[0040] The FPC 30 is attached to the binding area of ​​the inner surface of the bottom plate (i.e., the inner bottom surface) of the back plate 10 through the first thermally conductive tape 61. According to an embodiment of the present disclosure, the first thermally conductive tape 61 may be a thermally conductive double-sided tape. The chip (die) (i.e., silicon-based OLED display panel) 20 formed after wafer cutting is connected to the inner bottom surface (i.e., the attachment area) of the back plate 10 through the first thermally conductive tape 61. While the silicon-based OLED display panel 20 is fixed, the heat generated in the silicon-based OLED display panel 20 can be introduced into the back plate, and further introduced into the air or other heat dissipation structures of the whole machine, thereby improving the heat dissipation performance of the device.

[0041] Since the backplane 10 has an opening structure, the edge of the metal bottom plate on the side of the opening structure is exposed, resulting in the risk of cutting the FPC. Therefore, in one embodiment of the present disclosure, a protective tape 60 is attached to the exposed edge of the metal bottom plate to protect the FPC from being cut when it is bent.

[0042] According to an embodiment of the present disclosure, an adhesive tape 62 is attached to the FPC attached to the back plate 10 to bond the sealing strip 63 to the FPC, and the groove on the frame of the back plate 10 is used to limit the position.

[0043] The silicon-based OLED display panel 20 in the embodiment of the present disclosure includes a silicon wafer 21 with a device layer and a cover glass (CG) 22, which form a step structure. According to an embodiment of the present disclosure, the upper glue frame 40 is arranged at the periphery of the above-mentioned step structure, and has an integral structure formed by injection molding, which is used to fill the gap between the silicon wafer 21 with a device layer and the cover glass 22. If the solution of maximizing the cover glass 22 is adopted, the upper glue frame 40 can be omitted.

[0044] According to an embodiment of the present disclosure, a shading material 50 is attached to the upper surface of the back panel 10 provided with the above-mentioned structure to prevent light leakage. The prior art generally uses black thermosetting glue to wrap around the cover glass 22 to reduce light leakage, but the actual glue surface cannot be 100% flush with the cover glass surface, and there must be a certain gap, resulting in light leakage. The shading material 50 of the embodiment of the present disclosure can completely cover the part where light leakage may occur, thereby 100% eliminating the phenomenon of light leakage. Optionally, the shading material 50 can be a shading tape.

[0045] The silicon-based OLED display module in the disclosed embodiment can effectively protect the silicon wafer through thermal conductive tape, protective tape and shading material, prevent or eliminate the black screen caused by scratches or edge collapse of the silicon wafer, and can enhance the heat dissipation performance and anti-static release (ESD) capability of the module, eliminate peripheral light leakage in the AA area, and enhance the FPC's anti-pull ability, thereby avoiding short circuit problems caused by poor chip bonding.

[0046] See also Figure 4 , an embodiment of the present disclosure provides an assembly method of a silicon-based OLED display module, comprising the following steps.

[0047] S1: Provide a back plate with a frame and an opening structure on one side. The material and structure of the back plate are as defined above, that is, it has a metal bottom plate-plastic frame integrated structure and has an opening structure on one side.

[0048] S2: Attach the silicon-based OLED display panel to the attachment area on the inner bottom surface of the backplane. That is, after the wafer is cut, the chip (die, including the silicon-based substrate with the device layer and the cover glass) is attached to the attachment area on the inner surface of the bottom plate of the backplane, which is the die bonding process.

[0049] S3: Wire bonding (WB) is performed on the silicon-based OLED display panel and the circuit board assembly in the binding area other than the attachment area on the inner bottom surface of the backplane. The circuit board here can be a flexible printed circuit board FPC. In this step, the bonding pad on the chip is connected to the bonding pad on the FPC through a metal wire. The metal wire can be made of a metal material with good conductivity, preferably a gold wire.

[0050] After the S3 step, the WB area may be filled with glue with poor fluidity and filling glue in order to protect the bonded metal wires. However, if the metal wires are gold wires, this step may be omitted.

[0051] S4: Assemble the sealing strip at the opening structure of the backplane binding area on the circuit board assembly. The sealing strip is assembled by attaching a sealing strip tape to the opening structure, thereby bonding the sealing strip to the FPC. At the same time, since the backplane frame has groove structures at both ends of the opening structure, the sealing strip can be limited.

[0052] S5: Assemble the glue frame around the silicon-based OLED display panel. According to one embodiment, the silicon-based OLED display panel is formed by forming a device layer on a silicon-based substrate, and disposing a cover glass on the device layer, and a step portion is formed between the cover glass and the device layer. According to the embodiment of the present disclosure, the glue frame is assembled on the step portion to fill the space between the cover glass and the device layer to further prevent or eliminate light leakage. However, if the cover glass maximization solution is adopted, this step can be omitted.

[0053] S6: attaching a light shielding material on the back plate assembled with the above sealing strip and the optional glue frame. According to an embodiment of the present disclosure, the light shielding material can be a light shielding tape with good light shielding performance to play the role of light shielding and beautifying external light.

[0054] According to one embodiment, the assembly method of the present disclosure further includes the following steps: attaching a protective tape to the edge of the metal base plate exposed at the opening structure of the base plate to prevent the exposed edge of the base plate from damaging the silicon-based substrate.

[0055] According to another aspect of the present disclosure, a silicon-based OLED display module assembled according to the above-mentioned assembly method is provided.

[0056] According to another aspect of the present disclosure, a display device including the silicon-based OLED display module is provided.

[0057] The conventional assembly method is to wrap the periphery of the cover glass with black thermosetting glue to reduce light leakage, but in reality the surface of the glue after curing cannot be 100% flush with the surface of the cover glass, so there must be a certain gap, resulting in light leakage. The assembly method disclosed in the present invention connects the silicon-based OLED display panel to the bottom surface of the metal alloy backplane through thermal conductive tape, and adopts a split glue frame to perform the FPC bonding process, which can avoid short circuits between pins caused by poor bonding, thereby avoiding defects such as black screens or abnormal displays, and at the same time improve the FPC's anti-pulling ability and the module's anti-static release performance; using shading materials to completely cover the backplane can enhance the heat dissipation performance of the silicon-based OLED display module, 100% eliminate light leakage, and at the same time make the product have better flatness and appearance; secondly, the use of an injection-molded metal-plastic integrated backplane greatly improves the dimensional accuracy of the product; thirdly, using tape as the main fixing method has better elasticity than thermosetting glue, which can reduce the stress transfer between components of the product during hot and cold shocks, thereby reducing the risk of component tearing during hot and cold shocks.

[0058] In the description of this specification, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present disclosure.

[0059] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present disclosure, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0060] In the present disclosure, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0061] In the present disclosure, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being “above”, “above”, and “above” a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0062] The disclosure above provides many different embodiments or examples to realize different structures of the present disclosure. In order to simplify the disclosure of the present disclosure, the components and settings of specific examples are described above. Of course, they are only examples, and the purpose is not to limit the present disclosure. In addition, the present disclosure can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed.

[0063] The above are only specific embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any technician familiar with the technical field can easily think of various changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A method for assembling a silicon-based OLED display module, wherein the silicon-based OLED display module comprises a silicon-based OLED display panel, a circuit board assembly and a backplane, characterized in that: The assembly method comprises: A back plate having a frame and an opening structure on one side is provided; the back plate is a metal-plastic integrated structure; the bottom surface of the back plate is a metal material; the frame of the back plate is a plastic material; Attaching the silicon-based OLED display panel to the attachment area of ​​the inner bottom surface of the backplane by means of a first thermally conductive tape; A third adhesive tape is attached to the edge of the bottom plate of the opening structure of the back plate to prevent damage to the circuit board assembly; Wire bonding the silicon-based OLED display panel to the circuit board assembly in a binding area other than the attachment area on the inner bottom surface of the backplane; Adhere a sealing strip to the circuit board assembly at the opening structure of the back plate on the circuit board assembly by a second adhesive tape, and the opening structure of the back plate is closed by the sealing strip; and A light shielding material is attached above the back plate assembled with the sealing strip.

2. The assembly method according to claim 1, characterized in that: Grooves are formed on the frames at both sides of the bottom plate opening structure, and the sealing strip is limited by the grooves.

3. The assembly method according to claim 1, characterized in that: The silicon-based OLED display panel is formed by forming a device layer on a silicon-based substrate, and arranging a cover glass on the device layer, and forming a step portion between the cover glass and the device layer; The assembling method further comprises assembling a glue frame on the step portion to fill the space between the cover glass and the device layer.

4. The assembly method according to claim 1, characterized in that: The wire bonding includes attaching the silicon-based OLED display panel to an attachment area on the inner bottom surface of the backplane from one side of the opening structure.

5. The assembly method according to claim 1, characterized in that: The wire bonding includes connecting bonding pads on the silicon-based OLED display panel to bonding pads on the circuit board assembly.

6. A silicon-based OLED display module, characterized in that: Assembled by the assembly method according to any one of claims 1 to 5.

7. A silicon-based OLED display module, comprising a silicon-based OLED display panel, a circuit board assembly and a backplane, characterized in that: in, The back plate has a frame and an opening structure on one side, and the inner bottom surface includes an attachment area and a binding area; the back plate is a metal-plastic integrated structure; the bottom surface of the back plate is a metal material; the frame of the back plate is a plastic material; The silicon-based OLED display panel is thermally connected to the attachment area via a first thermally conductive tape; A third adhesive tape is attached to the bottom plate edge of the opening structure of the back plate to prevent damage to the circuit board assembly; The silicon-based OLED display panel is wire-bonded to the circuit board assembly in the binding area; The circuit board assembly is bonded with a sealing strip via a second adhesive tape, and the sealing strip is located at the opening structure of the back plate, and the opening structure of the back plate is closed by the sealing strip; and The upper surface of the back plate is covered with a light-shielding material.

8. The silicon-based OLED display module according to claim 7, characterized in that: The back plate has a metal-plastic integrated structure.

9. The silicon-based OLED display module according to claim 7, characterized in that: The frame ends on both sides of the opening structure of the back plate are respectively provided with grooves for limiting the sealing strip.

10. A display device, characterized in that: It comprises a silicon-based OLED display module according to any one of claims 6 to 9.

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