Intermediate substrate and preparation method of display panel

Abstract

An interposer substrate (1) includes: a first substrate (19); the black photoresist material layer (41) is arranged on one side of the first substrate (19); the light-emitting devices (3) are arranged on one side, far away from the first substrate (19), of the black photoresist material layer (41); the light emitting device (3) is provided with a light emitting side (391) for emitting light emitted by the light emitting device (3), and the light emitting side (391) is in contact with the black photoresist material layer (41); the light emitting device (3) comprises a drive electrode (31) for introducing a drive signal.

Description

[0001] This application is a divisional application of patent application No. 202080000856.2, filed on May 28, 2020, entitled "Method for preparing an intermediate substrate and a display panel". Technical Field

[0002] This disclosure relates to the field of display technology, and in particular to methods for preparing intermediate substrates and display panels. Background Technology

[0003] Light-emitting diode (LED) display technology has attracted increasing attention due to its advantages such as high dynamic contrast and high brightness.

[0004] A light-emitting diode (LED) display panel includes a driving substrate with driving circuitry. Multiple LEDs can be first fabricated on another substrate (such as a sapphire substrate) and then "transferred" (e.g., mass transfer) onto the driving substrate. This process separates the LEDs from their original substrate and electrically connects them to the driving circuitry on the driving substrate. Simultaneously, it achieves a physical connection between the LEDs and the driving substrate, for example, by electrically connecting the cathode and anode of the LEDs to their respective driving connectors. To prevent crosstalk (or color mixing) from light emitted by different light-emitting devices (and different pixels or subpixels), a black matrix (BM) needs to be formed between the gaps between the different light-emitting devices.

[0005] It is evident that the fabrication of LED display panels involves multiple steps, such as the transfer of LEDs and the fabrication of the black matrix, resulting in a complex, costly, and inefficient manufacturing process. Summary of the Invention

[0006] This disclosure provides a method for preparing an intermediate substrate and a display panel.

[0007] In a first aspect, embodiments of this disclosure provide an intermediate substrate, comprising:

[0008] First substrate;

[0009] A black photoresist layer disposed on one side of the first substrate;

[0010] A plurality of light-emitting devices are disposed on the side of the black photoresist material layer away from the first substrate; the light-emitting devices have a light-emitting side for emitting light emitted by the light-emitting devices, the light-emitting side being in contact with the black photoresist material layer; the light-emitting devices include a driving electrode for introducing a driving signal.

[0011] In some embodiments, the light-emitting device has a connection side opposite to the light-emitting side, and the driving electrode is disposed on the connection side.

[0012] In some embodiments, the light emitting device is a light emitting diode, and the driving electrode is a cathode and an anode arranged in a spaced manner.

[0013] In some embodiments, the thickness of the black photoresist material layer is substantially the same as the thickness of the light emitting device.

[0014] In some embodiments, the black photoresist material layer comprises:

[0015] Silica gel;

[0016] Carbon black distributed in the silica gel.

[0017] In some embodiments, the first substrate is further provided with a first alignment mark.

[0018] In some embodiments, the first substrate is made of a transparent material.

[0019] In a second aspect, the embodiments of the present disclosure provide a preparation method of a display panel, comprising:

[0020] providing a driving substrate and an intermediate substrate; the driving substrate comprises a second substrate, and a driving circuit is arranged on one side of the second substrate, wherein the driving circuit comprises a plurality of driving contacts; the intermediate substrate comprises a first substrate, a black photoresist material layer arranged on one side of the first substrate, and a plurality of light emitting devices arranged on the side of the black photoresist material layer away from the first substrate; the light emitting device has a light emitting side for emitting light emitted by the light emitting device, and the light emitting side is in contact with the black photoresist material layer; the light emitting device comprises a driving electrode for introducing a driving signal;

[0021] arranging the side of the intermediate substrate provided with the light emitting device opposite to the side of the driving substrate provided with the driving circuit, so that at least part of the driving electrode is electrically connected to the driving contact;

[0022] pressing the first substrate and the second substrate together, so that the light emitting device is embedded in the black photoresist material layer to expose the light emitting side of the light emitting device, and the black photoresist material layer forms a black matrix.

[0023] In some embodiments, the light emitting device has a connecting side opposite to the light emitting side, and the driving electrode is arranged on the connecting side.

[0024] In some embodiments, the first substrate is further provided with a first alignment mark, and the second substrate is further provided with a second alignment mark.

[0025] The arrangement of the side of the intermediate substrate provided with the light emitting device opposite to the side of the driving substrate provided with the driving circuit comprises:

[0026] The side of the interposer substrate provided with the light emitting device is opposite to the side of the driving substrate provided with the driving circuit, and the first alignment mark is aligned with the second alignment mark.

[0027] In some embodiments, the pressing the first substrate and the second substrate together includes:

[0028] The first substrate and the second substrate are pressed together in a heated vacuum environment.

[0029] The black photoresist material layer is cured in a heated inert gas environment.

[0030] In some embodiments, the first substrate is made of transparent material.

[0031] The first substrate is a cover plate of a display panel.

[0032] In some embodiments, after the pressing the first substrate and the second substrate together, the method further includes:

[0033] Separating the first substrate from the black matrix and the light emitting device. BRIEF DESCRIPTION OF DRAWINGS

[0034] The accompanying drawings are included to provide a further understanding of embodiments of the present disclosure and are incorporated in and constitute a part of the specification, illustrate embodiments of the present disclosure and serve to explain the principles of the present disclosure, and do not constitute a limitation of the present disclosure. The above and other features and advantages will become more apparent from the detailed description of the specific embodiments described below, taken in conjunction with the accompanying drawings, in which:

[0035] Figure 1 A top view structural schematic diagram of an interposer substrate provided by an embodiment of the present disclosure;

[0036] Figure 2 A top view structural schematic diagram of a driving substrate used in a display panel preparation method provided by an embodiment of the present disclosure; Figure 1

[0037] A cross-sectional structural schematic diagram along AA’; Figure 3

[0038] A cross-sectional structural schematic diagram along BB’; Figure 4 Figure 3 A cross-sectional structural schematic diagram of an interposer substrate and a driving substrate when they are opposite to each other in a display panel preparation method provided by an embodiment of the present disclosure;

[0039] Figure 5 A cross-sectional structural schematic diagram of an interposer substrate and a driving substrate before they are pressed together in a display panel preparation method provided by an embodiment of the present disclosure;

[0040] Figure 6 ​​

[0041] Figure 7 This is a schematic cross-sectional view of a display panel prepared by a method for preparing a display panel according to an embodiment of the present disclosure.

[0042] Figure 8 A photograph of a display panel prepared by a method for preparing a display panel according to an embodiment of this disclosure;

[0043] Figure 9 This is a schematic cross-sectional view of the structure before the third substrate is joined to the first substrate in a method for preparing an intermediate substrate according to an embodiment of this disclosure.

[0044] 1. Intermediate substrate; 11. First alignment mark; 19. First substrate; 2. Driving substrate; 21. Driving connector; 22. Second alignment mark; 29. ​​Second substrate; 3. Light-emitting device; 31. Driving electrode; 391. Light-emitting side; 392. Connecting side; 41. Black photoresist layer; 42. Black matrix; 6. Display panel; 79. Third substrate; 9. Conductive adhesive. Detailed Implementation

[0045] To enable those skilled in the art to better understand the technical solutions of the embodiments of this disclosure, the preparation methods of the intermediate substrate and display panel provided in the embodiments of this disclosure will be described in detail below with reference to the accompanying drawings.

[0046] Embodiments of this disclosure will be described more fully below with reference to the accompanying drawings; however, the embodiments shown may be embodied in different forms and should not be construed as limited to the embodiments set forth in this disclosure. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will enable those skilled in the art to fully understand the scope of this disclosure.

[0047] Embodiments of this disclosure can be described with reference to plan views and / or cross-sectional views, taking into account the ideal schematic diagrams of this disclosure. Therefore, the example illustrations may be modified according to manufacturing techniques and / or tolerances.

[0048] Where there is no conflict, the various embodiments of this disclosure and the features thereof in the embodiments may be combined with each other.

[0049] The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to limit the disclosure. The term "and / or" as used in this disclosure includes any and all combinations of one or more of the associated enumerated entries. The singular forms "a" and "the" as used in this disclosure are also intended to include the plural forms, unless the context clearly indicates otherwise. The terms "comprising," "made of," etc., as used in this disclosure specify the presence of the stated feature, integral, step, operation, element, and / or component, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof.

[0050] Unless otherwise specified, all terms used in this disclosure (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and this disclosure, and will not be interpreted as having an idealized or overly formal meaning, unless expressly so defined in this disclosure.

[0051] This disclosure is not limited to the embodiments shown in the accompanying drawings, but includes modifications to the configuration based on the manufacturing process. Therefore, the areas illustrated in the drawings are schematic, and the shapes of the areas shown illustrate specific shapes of the areas of an element, but are not intended to be limiting.

[0052] Firstly, referring to Figures 1 to 8 This disclosure provides an intermediate substrate 1.

[0053] The intermediate substrate 1 of this disclosure is used to prepare a display panel 6, and more particularly to prepare a light-emitting diode (LED) display panel.

[0054] The intermediate substrate 1 in this embodiment includes:

[0055] First substrate 19;

[0056] A black photoresist layer 41 is disposed on one side of the first substrate 19;

[0057] Multiple light-emitting devices 3 are disposed on the side of the black photoresist layer 41 away from the first substrate 19; the light-emitting device 3 has a light-emitting side 391 for emitting light emitted by the light-emitting device 3, the light-emitting side 391 being in contact with the black photoresist layer 41; the light-emitting device 3 includes a driving electrode 31 for introducing a driving signal.

[0058] Reference Figure 1 , Figure 2 The intermediate substrate 1 in this embodiment includes a first substrate 19.

[0059] A black photoresist layer 41 is provided on the first substrate 19, which is a layer made of an opaque black material that can block all visible light. In other words, the material of the black photoresist layer 41 is the same material that constitutes the Black Matrix (BM). However, the black photoresist layer 41 is a complete layer, rather than a "matrix" shape.

[0060] On the complete black photoresist layer 41, multiple light-emitting devices 3 are also provided, which are devices that emit light when powered on and serve as a pixel (or sub-pixel) of the display panel 6. One side of the light-emitting device 3 is the light-emitting side 391, which is the side of the display panel 6 that faces outward (towards the user). The light-emitting device 3 is also provided with a driving electrode 31. By connecting the driving electrode 31 to the driving connector 21 (Pad) of the driving circuit, a driving signal can be introduced into the light-emitting device 3 to drive the light-emitting device 3 to emit light of the required brightness for display.

[0061] Reference Figure 2 The above light-emitting device 3 is disposed on the black photoresist layer 41 in such a way that the light-emitting side 391 is in contact with the black photoresist layer 41.

[0062] Among them, multiple light-emitting devices 3 are usually arranged in an "array", or in other words, the positional distribution of the light-emitting devices 3 is the same as the distribution of each pixel (or sub-pixel) in the display panel 6.

[0063] In this embodiment, a black photoresist layer 41 and a light-emitting device 3 are simultaneously disposed on the intermediate substrate 1. Therefore, during the process of "transferring" the light-emitting device 3 to the driving substrate 2, which has a driving circuit, and electrically connecting it to the driving connector 21, the black photoresist layer 41 can also be simultaneously transferred to the driving substrate 2, and a black matrix 42 (BM) is formed using the black photoresist layer 41. Thus, this embodiment can complete the transfer of the light-emitting device 3 and the fabrication of the black matrix 42 in one step, simplifying the fabrication process of the display panel 6, reducing fabrication costs, and improving fabrication efficiency.

[0064] In some embodiments, the light-emitting device 3 has a connection side 392 opposite to the light-emitting side 391, and the driving electrode 31 is disposed on the connection side 392.

[0065] Reference Figure 2 The side of the light-emitting device 3 opposite to the light-emitting side 391 is the connection side 392, which is the side that is "facing" the driving substrate 2. The driving electrode 31 of the light-emitting device 3 is located on the connection side 392, so the driving electrode 31 is "exposed" and can be directly contacted and connected to the driving connector 21 (Pad) of the driving circuit.

[0066] Of course, it is also feasible to place the driving electrode 31 in other positions of the light-emitting device 3.

[0067] For example, a portion of the driving electrode 31 may be located on the light-emitting side 391 (i.e., the light-emitting device 3 is a vertical structure) and used for electrical connection with the driving structure on the cover of the display panel 6; or, the light-emitting device 3 may also include an outer surface connected between the light-emitting side 391 and the connecting side 392, and the driving electrode 31 may be disposed on the outer surface.

[0068] In some embodiments, the light-emitting device 3 is a light-emitting diode, and the driving electrode 31 consists of a cathode and an anode spaced apart.

[0069] As one embodiment of this disclosure, the light-emitting device 3 can be a light-emitting diode (LED), that is, the intermediate substrate 1 can be used to fabricate a light-emitting diode display panel. Accordingly, the driving electrode 31 of the light-emitting device 3 is the cathode and anode (or positive and negative electrode) of the light-emitting diode.

[0070] Light-emitting diode (LED) display panels have a wide range of applications, including conventional displays (such as computer screens and mobile phone screens), virtual reality (VR) displays, augmented reality (AR) displays, and large-scale displays such as billboards and movie screens. Furthermore, LED display panels can be rigid or flexible and deformable.

[0071] In some embodiments, the light-emitting diode is a millimeter-scale light-emitting diode or a sub-millimeter-scale light-emitting diode.

[0072] Furthermore, the aforementioned light-emitting diode devices can be smaller light-emitting diodes, such as micro-LEDs or mini-LEDs, to improve the resolution of the corresponding display panel 6 and enhance the display effect.

[0073] Generally speaking, the size of a millimeter-scale light-emitting diode (Micro-LED) (based on the maximum size of its light-emitting side 391 in any direction) can be above 100µm, for example, 120µm; while the size of a sub-millimeter-scale light-emitting diode (Mini-LED) can be below 100µm, for example, 50µm.

[0074] In some embodiments, the thickness of the black photoresist layer 41 is substantially the same as the thickness of the light-emitting device 3.

[0075] Reference Figure 2 The thickness of the black photoresist layer 41 (the dimension in the direction perpendicular to the first substrate 19) can be set as needed. However, since the black photoresist layer 41 needs to be "squeezed" into the gap between the light-emitting devices 3 to form a black matrix 42, the thickness of the black photoresist layer 41 should be basically the same as the thickness of the light-emitting devices 3 to ensure that the black matrix 42 formed later is basically "flat" with the light-emitting devices 3, that is, to achieve sufficient light blocking effect without "burying" the light-emitting devices 3.

[0076] The phrase "basically the same" means that if the thickness of the light-emitting device 3 is 100%, the thickness of the black photoresist layer 41 can be in the range of 85% to 115%, further in the range of 90% to 110%, and further in the range of 95% to 105%.

[0077] For example, if the light-emitting device 3 (such as Micro-LED) does not include an epitaxial substrate, its thickness is usually around 10µm; while when the light-emitting device 3 (such as Mini-LED) has an epitaxial substrate, its thickness is usually 200~300µm. Therefore, the thickness of the black photoresist layer 41 can be 10~300µm.

[0078] The thickness difference between the different structures in the driving circuit is small, so it can be basically ignored when determining the thickness of the black photoresist layer 41.

[0079] In some embodiments, the black photoresist layer 41 includes:

[0080] Silicone;

[0081] Carbon black distributed in silica gel.

[0082] In some embodiments, the mass percentage of carbon black in the black photoresist layer 41 is 10% to 80%.

[0083] The black photoresist layer 41 can be made of silicone and carbon black (a black pigment) mixed therein. The amount of carbon black can be set as needed (the more carbon black used, the "blacker" the black photoresist layer 41 will be, and the better the photoresist effect will be), but its mass percentage is usually between 10% and 80%.

[0084] Specifically, the black photoresist layer 41 can be prepared by means of an adhesive film. The adhesive film is an independent film layer composed of silicone and carbon black with a predetermined thickness. Both sides of the film are adhesive and are respectively attached with release films (such as PET films). Specifically, the release film on one side of the adhesive film can be peeled off first to bond the adhesive film to the first substrate 19 to form the black photoresist layer 41. Then, the release film on the other side can be peeled off so that the light-emitting device 3 (such as a light-emitting diode) can be subsequently disposed on the black photoresist layer 41 (such as bonded to the black photoresist layer 41).

[0085] In some embodiments, the first substrate 19 is further provided with a first alignment mark 11.

[0086] Reference Figure 1 A first alignment mark 11 may also be formed on the first substrate 19. The first alignment mark 11 is used to align the second alignment mark 22 of the drive substrate 2 to ensure that each light-emitting device 3 of the intermediate substrate 1 can be accurately connected to the corresponding drive connector 21 of the drive substrate 2.

[0087] The first alignment mark 11 and the second alignment mark 22 should be able to cooperate with each other, and their specific forms are diverse.

[0088] For example, the first alignment mark 11 and the second alignment mark 22 may include patterns that can match each other, such as one of which includes multiple "cross" shapes located at different positions (such as the four corners of the substrate), while the other includes multiple patterns located at corresponding positions, each pattern having a "cross" shaped opening, which will not be described in detail here.

[0089] For example, the first alignment mark 11 can also be a larger graphic, such as an alignment box, to be opposite to the corresponding second alignment mark 22.

[0090] In some embodiments, the first substrate 19 is made of a transparent material.

[0091] As one embodiment of this disclosure, the first substrate 19 may be made of a transparent material, thereby allowing light emitted by the light-emitting device 3 to pass through it. Therefore, during the fabrication of the display panel 6, the first substrate 19 need not be separated, but can remain in the display panel 6 as a cover plate (or substrate) to protect the light-emitting device 3 and other display structures.

[0092] Thus, this embodiment of the present disclosure completes the three processes of transferring the light-emitting device 3, preparing the black matrix 42, and aligning the cover plate with the cell in a single process step, which can further simplify the manufacturing process of the display panel 6, reduce manufacturing costs, and improve manufacturing efficiency.

[0093] Meanwhile, according to the above method, the black matrix 42 can also serve to bond the first substrate 19 (cover plate) to fix it; thus, there is no need to separately prepare a protective layer (OC) to bond the cover plate in the display panel 6, which also simplifies the structure of the display panel 6.

[0094] In some embodiments, the transparent material is glass.

[0095] Specifically, the first substrate 19 (that is, the cover plate of the display panel 6) can be made of glass, for example, glass with a thickness of 0.2~0.5mm.

[0096] Of course, it is also feasible if the first substrate 19 is made of other transparent materials such as transparent polyimide (CPI), transparent polyethylene terephthalate (PET).

[0097] Secondly, referring to Figures 1 to 8 This disclosure provides a method for manufacturing a display panel 6.

[0098] The preparation method of this disclosure is used to prepare a display panel 6 using any of the above-mentioned intermediate substrates 1.

[0099] The method for manufacturing the display panel 6 according to the embodiments of this disclosure includes:

[0100] S201, Provide a driving substrate 2 and an intermediate substrate 1.

[0101] The driving substrate 2 includes a second substrate 29, and a driving circuit is provided on one side of the second substrate 29. The driving circuit includes a plurality of driving connectors 21.

[0102] The intermediate substrate 1 includes: a first substrate 19; a black photoresist layer 41 disposed on one side of the first substrate 19; a plurality of light-emitting devices 3 disposed on the side of the black photoresist layer 41 away from the first substrate 19; the light-emitting device 3 has a light-emitting side 391 for emitting light emitted by the light-emitting device 3, the light-emitting side 392 being in contact with the black photoresist layer 41; the light-emitting device 3 includes a driving electrode 31 for introducing a driving signal.

[0103] Reference Figures 1 to 4 Prepare a driving substrate 2 and an intermediate substrate 1 respectively.

[0104] Wherein, the intermediate substrate 1 can be any of the above-mentioned intermediate substrates 1, and will not be described in detail here.

[0105] Reference Figure 3 , Figure 4 The driving substrate 2 includes a second substrate 29 and a driving circuit disposed on the second substrate 29.

[0106] Among them, the driving circuit refers to the circuit that can drive the light-emitting device 3 (such as a light-emitting diode) to emit light of the required brightness for display.

[0107] Specifically, the driving circuit includes a driving connector 21 (Pad) for connecting to the driving electrodes 31 of the light-emitting device 3 (such as the cathode and anode of a light-emitting diode), and other parts that provide driving signals to the driving connector 21, such as gate lines, data lines, storage capacitors (Cst), transistors (TFTs), etc. The specific form of the driving circuit is diverse, so it will not be described in detail here.

[0108] The drive circuit is not a complete layer, so it is not shown in the figures, but only the drive connector 21 is schematically shown.

[0109] The driving substrate 2 and the intermediate substrate 1 provided above can be purchased products or directly prepared, and will not be described in detail here.

[0110] S202, the side of the intermediate substrate 1 with the light-emitting device 3 is placed opposite the side of the driving substrate 2 with the driving circuit, so that at least a portion of the driving electrodes 31 of the light-emitting device 3 are electrically connected to the driving connector 21 of the driving circuit.

[0111] Reference Figure 5 , Figure 6 The side of the intermediate substrate 1 with the light-emitting device 3 is placed towards the side of the driving substrate 2 with the driving circuit, and the two are gradually brought closer together, so that the driving electrode 31 of the light-emitting device 3 is electrically connected to the corresponding driving connector 21 of the driving circuit.

[0112] For example, the driving substrate 2 can be placed on the base of the pressure-bearing film laminating machine with the side having the driving circuit facing upward; while the intermediate substrate 1 is positioned with the side having the light-emitting device 3 facing downward (such as by adsorption), and then the driving electrode 31 is gradually brought closer to the driving connector 21.

[0113] Of course, it should be understood that when some of the driving electrodes 31 are not located on the side facing the driving substrate 2, these driving electrodes 31 may also be electrically connected to other driving structures (such as driving structures located on the cover plate).

[0114] S203. Press the first substrate 19 and the second substrate 29 together so that the light-emitting device 3 is embedded in the black photoresist material layer 41 until the light-emitting side 391 of the light-emitting device 3 is exposed, and the black photoresist material layer 41 forms a black matrix 42.

[0115] Reference Figure 5 , Figure 6 After the driving electrode 31 is electrically connected to the driving connector 21, the first substrate 19 is pressed against the second substrate 29 (i.e., "pressed together").

[0116] Since the black photoresist layer 41 is a relatively soft and deformable material, while the driving electrode 31 and the driving connector 21 are relatively fixed structures, the black photoresist layer 41 will be squeezed and deformed, "squeezed" into the gaps between different light-emitting devices 3 (including the gaps between different driving electrodes 31 of the light-emitting device 3); at the same time, the black photoresist layer 41 originally located between the light-emitting side 391 of the light-emitting device 3 and the first substrate 19 is gradually "squeezed out", thereby exposing the light-emitting side 391 of the light-emitting device 3.

[0117] Finally, refer to Figure 7 The light-emitting side 391 of the light-emitting device 3 is in contact with the first substrate 19, so that the light emitted by it can be directly emitted for display; while the space between adjacent light-emitting devices 3 is filled with a black photoresist material layer 41 to prevent crosstalk and color mixing between different pixels (subpixels). Thus, the black photoresist material layer 41 distributed between adjacent light-emitting devices 3 constitutes a "black matrix 42"; thereby obtaining the display panel 6.

[0118] Of course, it should be understood that due to process limitations, a small amount of black matrix may remain on the light-emitting side 391 of the light-emitting device 3. However, because it is very thin, it cannot be formed into a specific structure in the process. At the same time, the transmittance of this very thin black matrix is ​​very high, and it will not affect the light from the light-emitting side 391 to the outside of the display panel 6 for display. Therefore, the remaining black matrix should be regarded as non-existent, that is, the light-emitting side 391 of the light-emitting device 3 can still be considered as "exposed".

[0119] Reference Figure 8 The partial photograph of the display panel 6 shows that the large black area is the black matrix 42, while the lighter rectangles are the light-emitting sides 391 of each light-emitting device 3. It can be seen that the light-emitting sides 391 of each light-emitting device 3 are very clear, which indicates that there is basically no residual black matrix on the light-emitting device 3. That is, it proves that the light-emitting side 391 of the light-emitting device 3 can be "exposed" by the method of the embodiments of this disclosure.

[0120] For example, the structure of the display panel 6 prepared by the method of this disclosure embodiment can be referred to Figure 7 Specifically, it can be any product or component with display function, such as electronic paper, mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, navigator, virtual reality (VR) display device, augmented reality (VR) display device, etc.; and it can be a rigid or a flexible display panel (determined by whether the first substrate 19 and the second substrate 29 are rigid or flexible).

[0121] In this embodiment, by pressing the black matrix 42, which has a black photoresist layer 41 and a light-emitting device 3, onto the driving substrate 2 in one process step, the transfer (electrical connection) of the light-emitting device 3 and the fabrication of the black matrix 42 can be completed simultaneously. This simplifies the fabrication process of the display panel 6 (such as a light-emitting diode display panel), reduces the fabrication cost, and improves the fabrication efficiency.

[0122] In some embodiments, the light-emitting device 3 has a connection side 392 opposite to the light-emitting side 391, and the driving electrode 31 is disposed on the connection side 392.

[0123] As before, when the driving electrodes 31 of the light-emitting device 3 are all located on the connection side 392, the driving electrodes 31 are all directly "facing" the driving substrate 2, so it is convenient to directly contact the driving connector 21 for electrical connection.

[0124] In some embodiments, the first substrate 19 is further provided with a first alignment mark 11; the second substrate 29 is further provided with a second alignment mark 22.

[0125] The above arrangement of the side of the intermediate substrate 1 where the light-emitting device 3 is located facing the side of the driving substrate 2 where the driving circuit is located (S202) includes:

[0126] S2021. Align the first alignment mark 11 with the second alignment mark 22 by placing the side of the intermediate substrate 1 with the light-emitting device 3 opposite to the side of the driving substrate 2 with the driving circuit.

[0127] Reference Figure 1 , Figure 3 When the first substrate 19 is provided with the first alignment mark 11, the second substrate 29 is also provided with the corresponding second alignment mark 22. Thus, the first alignment mark 11 and the second alignment mark 22 can be aligned first, so that the relative position of the intermediate substrate 1 and the driving substrate 2 is accurate. The driving electrode 31 of each light-emitting device 3 corresponds to the corresponding driving connector 21. Then, the driving electrode 31 of the light-emitting device 3 is electrically connected to the driving connector 21 of the driving circuit to ensure the accuracy of the connection.

[0128] In some embodiments, the above-described method of aligning the side of the intermediate substrate 1 where the light-emitting device 3 is located with the side of the driving substrate 2 where the driving circuit is located, and electrically connecting the driving electrode 31 of the light-emitting device 3 with the driving connector 21 of the driving circuit (S202) includes:

[0129] S2022. Conductive adhesive 9 is provided on the side of the drive connector 21 away from the second substrate 29, and the side of the intermediate substrate 1 with the light-emitting device 3 is opposite to the side of the drive substrate 2 with the drive circuit, so that the drive electrode 31 of the light-emitting device 3 is electrically connected to the drive connector 21 of the drive circuit through the conductive adhesive 9.

[0130] Reference Figures 5 to 7 In order to achieve electrical connection between the drive connector 21 and the drive electrode 31, one method is to apply conductive adhesive 9 to each drive connector 21 in advance, and then place the intermediate substrate 1 and the drive substrate 2 together and close to each other, so that the drive electrode 31 of the light-emitting device 3 also comes into contact with the conductive adhesive 9, so that the drive electrode 31 of the light-emitting device 3 and the drive connector 21 of the drive circuit are electrically connected through the conductive adhesive 9 (and also physically bonded through the conductive adhesive 9).

[0131] For example, the conductive adhesive 9 mentioned above can be anisotropic conductive adhesive (ACA), which is mainly used for conductivity in the direction from the driving electrode 31 to the driving connector 21.

[0132] For example, conductive adhesive 9 can be applied to the drive connector 21 in various ways, such as by IJP printing (inkjet printing) or by dispensing.

[0133] Of course, there are various ways to achieve electrical connection (including physical connection) between the drive electrode 31 and the drive connector 21.

[0134] For example, a "microtube" with an open top, made of a harder conductive material (such as titanium), can be provided on the drive connector 21, and the part of the drive electrode 31 that contacts the drive connector 21 is made of a softer conductive material (such as aluminum). Thus, the "microtube" can be "inserted" into the softer conductive material of the drive electrode 31 to simultaneously complete the physical and electrical connection between the drive electrode 31 and the drive connector 21.

[0135] Of course, it is also feasible to achieve the electrical connection between the drive electrode 31 and the drive connector 21 in other ways.

[0136] In some embodiments, pressing the first substrate 19 and the second substrate 29 together (S203) includes:

[0137] S2031. In a heated vacuum environment, the first substrate 19 and the second substrate 29 are pressed together.

[0138] S2032. The black photoresist layer 41 is cured in a heated inert gas environment.

[0139] When pressing the first substrate 19 and the second substrate 29 together, heating and vacuuming can be performed to allow the black photoresist layer 41 to better enter the gaps between different light-emitting devices 3 and to prevent gas from being trapped inside and generating bubbles. In addition, the above heating is also beneficial to the curing of the conductive adhesive 9 (such as ACA).

[0140] After pressing, the material can be heated for a period of time in an inert gas environment to solidify and shape the black photoresist layer 41, forming the black matrix 42 in the display panel 6.

[0141] In some embodiments, the temperature of the heated vacuum environment is between 100°C and 140°C, and the pressing pressure is between 0.1 MPa and 1 MPa.

[0142] The temperature during the pressing process can be between 100 and 140°C, for example, 110°C; and a vacuum environment can be achieved by evacuating for about 100 seconds.

[0143] The pressure of the press (i.e. the ratio of pressure to area of ​​the intermediate substrate 1) can be adjusted according to the effect of the black photoresist layer 41 entering the gap between different light-emitting devices 3, and it can usually be 0.1~1MPa, for example, 0.6MPa.

[0144] The pressure applied during the pressing process can be achieved in various ways.

[0145] For example, the space between the intermediate substrate 1 and the driving substrate 2 can be evacuated, while the side of the intermediate substrate 1 facing away from the driving substrate 2 is at atmospheric pressure, thereby generating the required pressing pressure through the pressure difference between the two sides of the intermediate substrate 1.

[0146] Alternatively, both the intermediate substrate 1 and the driving substrate 2 can be placed in a vacuum chamber, and the required pressing pressure can be generated by applying pressure to the intermediate substrate 1 through a mechanical structure.

[0147] In some embodiments, the temperature of the heated inert gas environment is between 150°C and 200°C, and the inert gas is nitrogen; the curing time for the black photoresist layer 41 is between 1 hour and 3 hours.

[0148] After pressing is completed, nitrogen (N2) can be used as an inert gas and heated at 150~200℃ for 2~3 hours to achieve curing, for example, heating at 170℃ for 2 hours to achieve curing.

[0149] In some embodiments, the first substrate 19 is made of a transparent material;

[0150] The first substrate 19 is the cover plate of the display panel 6.

[0151] As one embodiment of this disclosure, when the first substrate 19 is made of a transparent material (such as glass), after the pressing is completed, the first substrate 19 can be left in the display panel 6 as a cover plate (or a substrate) of the display panel 6.

[0152] As can be seen, by using the above method, the three processes of transferring the light-emitting device 3, preparing the black matrix 42, and aligning the cover plate to the cell are completed in one process step, which can further simplify the manufacturing process of the display panel 6, reduce the manufacturing cost, and improve the manufacturing efficiency.

[0153] Meanwhile, according to the above method, the black matrix 42 can also serve to bond the first substrate 19 (cover plate) to fix it; thus, there is no need to separately prepare a protective layer (OC) to bond the cover plate in the display panel 6, which also simplifies the structure of the display panel 6.

[0154] In some embodiments, after pressing the first substrate 19 and the second substrate 29 together (S203), the method further includes:

[0155] S204. Separate the first substrate 19 from the black matrix 42 and the light-emitting device 3.

[0156] As another embodiment of this disclosure, the second substrate 29 may not be used as a cover plate. Instead, after the pressing is completed, the first substrate 19 may be separated from the black matrix 42 and the light-emitting device 3 and "removed" so that subsequent steps, such as aligning with the cover plate, can be carried out.

[0157] When the light-emitting side 391 of the light-emitting device 3 has a driving electrode 31, the cover plate of the box may have a corresponding driving structure to be electrically connected to the driving electrode 31.

[0158] Thirdly, referring to Figures 1 to 9 This disclosure provides a method for preparing an intermediate substrate 1.

[0159] The method of this disclosure is used to prepare any of the above-mentioned intermediate substrates 1, and the intermediate substrate 1 can be used in the subsequent preparation process of the display panel 6.

[0160] The method for preparing the intermediate substrate 1 according to the embodiments of this disclosure includes:

[0161] S301. A black photoresist layer 41 is formed on one side of the first substrate 19.

[0162] S302, Multiple light-emitting devices 3 are disposed on the black photoresist material layer 41.

[0163] The light-emitting device 3 has a light-emitting side 391 for emitting light emitted by the light-emitting device 3, and the light-emitting side 392 is in contact with the black photoresist layer 41; the light-emitting device 3 includes a driving electrode 31 for introducing a driving signal.

[0164] In some embodiments, the light-emitting device 3 has a connection side 392 opposite to the light-emitting side 391, and the driving electrode 31 is disposed on the connection side 392.

[0165] Reference Figure 9 To prepare the above intermediate substrate 1, a black photoresist material layer 41 needs to be formed on the first substrate 19 first, and then the above light-emitting device 3 is disposed on the black photoresist material layer 41.

[0166] There are various ways to form the black photoresist layer 41.

[0167] For example, the aforementioned adhesive film can be attached to one side of the first substrate 19 to form a black photoresist layer 41.

[0168] Alternatively, a black photoresist layer 41 can be formed through other methods such as deposition.

[0169] In some embodiments, the arrangement of a plurality of light-emitting devices 3 on the black photoresist layer 41 (S302) includes:

[0170] S3021. Multiple light-emitting devices 3 are formed on the third substrate 79.

[0171] S3022, Transfer the light-emitting device 3 on the third substrate 79 to the black photoresist layer 41.

[0172] As one embodiment of this disclosure, the light-emitting device 3 can be disposed on the black photoresist material layer 41 by means of a "transfer" technique, especially a mass transfer technique. That is, multiple light-emitting devices 3 arranged in an array are first formed on another third substrate 79 (such as a sapphire substrate) by semiconductor process, and then the array of light-emitting devices 3 is "moved" as a whole to the black photoresist material layer 41.

[0173] For example, one feasible approach is to refer to Figure 9 The side of the third substrate 79 with the light-emitting device 3 (at this time, the driving electrode 31 of the light-emitting device 3 should be in contact with the third substrate 79) is directly brought into contact with the black photoresist material layer 41. Then, the light-emitting device 3 is separated from the third substrate 79 (such as by destroying the connection layer between the light-emitting device 3 and the third substrate 79 through light irradiation, dissolution, etc.), thereby transferring the light-emitting device 3 onto the black photoresist material layer 41.

[0174] Alternatively, the light-emitting device 3 on the third substrate 79 (at which time the light-emitting side 392 of the light-emitting device is in contact with the third substrate 79) can be transferred to the transition substrate (e.g., a "transfer stamp"). Then, the transition substrate is brought into contact with the black photoresist material layer 41, and the light-emitting device 3 is separated from the transition substrate (e.g., by destroying the connection layer between the light-emitting device 3 and the transition substrate through light irradiation, dissolution, etc.). Thus, the light-emitting device 3 is transferred to the black photoresist material layer 41.

[0175] Of course, it is also feasible to set multiple light-emitting devices 3 on the black photoresist layer 41 in other ways, such as directly preparing the light-emitting devices 3 on the black photoresist layer 41.

[0176] Of course, if the first substrate 19 is also provided with other structures such as the first alignment mark 11, the preparation method of this embodiment should also include the step of forming the first alignment mark 11 and other structures. These steps can be implemented by attachment and patterning processes, which will not be described in detail here.

[0177] This disclosure has disclosed exemplary embodiments, and although specific terminology has been used, it is for general illustrative purposes only and should not be construed as limiting. In some instances, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in conjunction with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in conjunction with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of this disclosure as set forth by the appended claims.

Claims

1. A display panel, characterized in that, include: Cover plate; A driving substrate, the driving substrate including a second substrate and a driving circuit disposed on the second substrate, the driving circuit including a plurality of driving connectors; Multiple light-emitting devices are located between the cover plate and the second substrate, and each light-emitting device includes a driving electrode, which is electrically connected to the driving connector. A black matrix is ​​located between a first substrate and a second substrate. The black matrix includes a portion located between adjacent light-emitting devices and a thin layer portion located on the light-emitting side of the light-emitting devices. The orthographic projection of the thin layer portion on the second substrate is located within the orthographic projection range of the light-emitting devices on the second substrate. The black matrix is ​​in contact with the cover plate, the driving substrate, and the light-emitting device.

2. The display panel according to claim 1, characterized in that, The cover plate is made of a transparent material; The cover plate is made of one of the following materials: glass, polyimide, or polyethylene terephthalate.

3. The display panel according to claim 1, characterized in that, The cover plate is made of glass; the thickness of the glass is in the range of 0.2 to 0.5 mm.

4. The display panel according to claim 1, characterized in that, The light-emitting device has a light-emitting side and a connection side, and the driving electrode is located on the connection side and is disposed towards the driving substrate.

5. The display panel according to claim 4, characterized in that, The driving electrode of the light-emitting device is electrically connected to the driving connector of the driving circuit through conductive adhesive.

6. The display panel according to claim 5, characterized in that, The conductive adhesive is anisotropic conductive adhesive.

7. The display panel according to any one of claims 1 to 6, characterized in that, The transmittance of the thin layer is greater than that of the portion of the black matrix located between adjacent light-emitting devices.

8. The display panel according to any one of claims 1 to 6, characterized in that, The thin layer portion has an unspecified structure.

9. The display panel according to any one of claims 1 to 6, characterized in that, The black matrix is ​​a solidified structure.

10. The display panel according to any one of claims 1 to 6, characterized in that, The light-emitting device is a light-emitting diode, and the driving electrodes are a cathode and an anode arranged at intervals.

11. The display panel according to claim 10, characterized in that, The light-emitting device is a millimeter-level light-emitting diode or a sub-millimeter-level light-emitting diode.

12. The display panel according to any one of claims 1 to 6, characterized in that, The black matrix includes: Silicone; Carbon black distributed in the silica gel.

13. The display panel according to any one of claims 1 to 6, characterized in that, The cover plate is also provided with a first alignment mark, and the driving substrate is provided with a second alignment mark. The first alignment mark and the second alignment mark are arranged in conjunction.

14. The display panel according to any one of claims 1 to 6, characterized in that, The light-emitting device is surrounded by the black matrix, and the space between adjacent light-emitting devices is filled with the black matrix.

15. The display panel according to any one of claims 1 to 6, characterized in that, The black matrix is ​​also located between two drive connectors that are electrically connected to the adjacent light-emitting devices.

16. A display panel, characterized in that, include: Cover plate; A driving substrate, the driving substrate including a second substrate and a driving circuit disposed on the second substrate, the driving circuit including a plurality of driving connectors; Multiple light-emitting devices are located between the cover plate and the second substrate, and each light-emitting device includes a driving electrode, which is electrically connected to the driving connector. A black matrix is ​​located between a first substrate and a second substrate. The black matrix includes a portion located between adjacent light-emitting devices and a thin layer portion located on the light-emitting side of the light-emitting devices. The orthographic projection of the thin layer portion on the second substrate is located within the orthographic projection range of the light-emitting devices on the second substrate. Each of the light-emitting devices is surrounded by the black matrix, and the space between any two adjacent light-emitting devices is filled with the black matrix.

17. The display panel according to claim 16, characterized in that, The cover plate is made of a transparent material; The cover plate is made of one of the following materials: glass, polyimide, or polyethylene terephthalate.

18. The display panel according to claim 16, characterized in that, The transmittance of the thin layer is greater than that of the portion of the black matrix located between adjacent light-emitting devices, and the thin layer has an unspecified structure.

19. The display panel according to claim 16, characterized in that, The black matrix includes: Silicone; Carbon black distributed in the silica gel.

20. The display panel according to any one of claims 16-19, characterized in that, At any height position of the light-emitting device, there exists a black matrix located between adjacent light-emitting devices; The black matrix is ​​also located between two drive connectors that are electrically connected to the adjacent light-emitting devices.

21. A display panel, characterized in that, include: Cover plate; A driving substrate, the driving substrate including a second substrate and a driving circuit disposed on the second substrate, the driving circuit including a plurality of driving connectors; Multiple light-emitting devices are located between the cover plate and the second substrate, and each light-emitting device includes a driving electrode, which is electrically connected to the driving connector. A black photoresist layer is located between a first substrate and a second substrate. A portion of the black photoresist layer is projected onto the second substrate between the projected images of adjacent light-emitting devices on the second substrate. A portion of the black photoresist layer is located on the light-emitting side of the light-emitting device and its projected image on the second substrate is within the projected image of the light-emitting device on the second substrate. The cover plate is made of a transparent material; the cover plate is made of one of the following materials: glass, polyimide, and polyethylene terephthalate.

22. The display panel according to claim 21, characterized in that, The portion of the black photoresist layer located on the light-emitting side of the light-emitting device has an unspecified structure.

23. The display panel according to claim 21, characterized in that, The portion of the black photoresist layer, whose orthographic projection is located between the orthographic projections of adjacent light-emitting devices on the second substrate, exists at any height position of the light-emitting devices.

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