Display panel manufacturing method and display panel

Abstract

The application discloses a display panel preparation method and a display panel. The display panel preparation method comprises the following steps: providing a first substrate, and forming a first electrode on the first substrate; coating photoresist on the side surface of the first electrode away from the first substrate and the first substrate between the first electrodes; performing hardening treatment on the photoresist between the adjacent first electrodes; providing a light-emitting element, and performing local pressing on the light-emitting element to electrically connect the light-emitting element and the first electrode. The photoresist between the adjacent first electrodes is subjected to the hardening treatment, so that the hardness of the photoresist between the adjacent first electrodes is improved. The photoresist of the hardened part is not easy to deform, and can limit the position of the light-emitting element connected with the first electrode, so as to avoid the problems of position deflection, mispositioning, deflection and the like of the light-emitting element in the local pressing process, and ensure the electrical connection effect between the light-emitting element and the first electrode of the first substrate.

Description

Technical Field

[0001] This invention belongs to the field of electronic product technology, and in particular relates to a method for preparing a display panel and the display panel itself. Background Technology

[0002] Light-emitting diodes (LEDs) are widely used in lighting and display technologies due to their advantages such as small size, low power consumption, long lifespan, and high brightness. Micro-LED displays, with their individual pixel arrays, offer better contrast, faster response times, and lower energy consumption compared to currently widely used display devices.

[0003] Because micro-LEDs are manufactured individually as chips, with dimensions on the micrometer scale, the fabrication of display devices requires transferring a massive number of these chips to appropriate locations on the substrate. However, due to limitations in existing processes and structures, the LED chips are prone to deflection or misalignment after transfer, resulting in a low transfer success rate.

[0004] Therefore, there is an urgent need for a new method for manufacturing display panels and a new display panel. Summary of the Invention

[0005] This invention provides a method for manufacturing a display panel and a display panel in which a portion of the photoresist between adjacent first electrodes is hardened to increase the hardness of the photoresist between adjacent first electrodes. The hardened photoresist can restrict the position of the light-emitting element connected to the first electrode to avoid problems such as positional deviation, misalignment, or displacement of the light-emitting element during the pressure process.

[0006] One embodiment of the present invention provides a method for manufacturing a display panel, comprising: providing a first substrate, wherein a first electrode is formed on the first substrate; coating photoresist on a side surface of the first electrode away from the first substrate and on the first substrate between the first electrodes; hardening a portion of the photoresist located between adjacent first electrodes; providing a light-emitting element, and applying pressure to the light-emitting element to electrically connect the light-emitting element and the first electrode.

[0007] According to one aspect of the present invention, the step of coating photoresist on the side surface of the first electrode away from the first substrate and on the first substrate between the first electrodes includes: coating a semi-solid photoresist on the side surface of the first electrode away from the first substrate and on the first substrate between the first electrodes.

[0008] According to one aspect of the invention, the thickness of the photoresist is greater than or equal to 8 μm.

[0009] According to one aspect of the invention, the step of hardening the portion of the photoresist located between adjacent first electrodes includes: exposing the portion of the photoresist located between adjacent first electrodes through a mask to harden the photoresist.

[0010] According to one aspect of the invention, the photoresist is a positive photoresist.

[0011] According to one aspect of the invention, after the steps of providing a light-emitting element and pressing the light-emitting element to electrically connect the light-emitting element and the first electrode, the method further includes: etching the photoresist of the hardened portion to form a groove between the first electrodes.

[0012] According to one aspect of the invention, after etching the photoresist on the hardened portion to form a groove between the first electrodes, the method further includes: forming a light-blocking portion in the groove, wherein the height of the light-blocking portion is greater than or equal to the height of the light-emitting element in a direction perpendicular to the plane of the first substrate.

[0013] According to one aspect of the present invention, the step of providing a light-emitting element and applying pressure to the light-emitting element to electrically connect the light-emitting element and the first electrode includes: providing a second substrate on which the light-emitting element is disposed; separating the light-emitting element from the second substrate so that the light-emitting element falls onto the first substrate; and applying pressure to the light-emitting element to electrically connect the light-emitting element and the first electrode.

[0014] According to one aspect of the invention, after the steps of providing a light-emitting element and applying pressure to the light-emitting element to electrically connect the light-emitting element and the first electrode, the method further includes: heating the unetched photoresist to cure the photoresist.

[0015] Another aspect of the present invention provides a display panel, which is formed by the display panel preparation method in any of the above embodiments.

[0016] Compared with the prior art, the display panel fabrication method provided in this embodiment of the invention coats photoresist on the surface of the first electrode facing away from the first substrate and on the first substrate between the first electrodes, and hardens the portion of photoresist located between adjacent first electrodes to increase the hardness of the portion of photoresist between adjacent first electrodes. This makes the hardened portion of photoresist less prone to deformation during the pressing step, thus restricting the position of the light-emitting element connected to the first electrode. This avoids problems such as positional deviation, misalignment, or displacement of the light-emitting element during the pressing process, ensuring the electrical connection effect between the light-emitting element and the first electrode of the first substrate, and improving the success rate of light-emitting element transfer. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart of a display panel manufacturing method provided in one embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of the structure during the fabrication process of a display panel fabrication method provided in one embodiment of the present invention;

[0020] Figure 3 This is a schematic diagram of the structure during the fabrication process of a display panel fabrication method provided in another embodiment of the present invention;

[0021] Figure 4 This is a schematic diagram of the structure during the fabrication process of a display panel fabrication method provided in another embodiment of the present invention;

[0022] Figure 5 This is a schematic diagram of the structure during the fabrication process of a display panel fabrication method provided in another embodiment of the present invention;

[0023] Figure 6 This is a schematic diagram of the structure during the fabrication process of a display panel fabrication method provided in another embodiment of the present invention;

[0024] Figure 7 This is a schematic diagram of the structure during the fabrication process of a display panel fabrication method provided in another embodiment of the present invention;

[0025] Figure 8 This is a schematic diagram of the structure during the fabrication process of a display panel fabrication method provided in another embodiment of the present invention.

[0026] In the attached image:

[0027] 1-First substrate; 11-First electrode; 2-Photoresist; 21-Photoresist in the hardened portion; 3-Light-emitting element; 4-Second substrate; 41-Adhesive layer; C-Groove; T-Driving transistor; S-Source; D-Drain; G-Gate. Detailed Implementation

[0028] The features and exemplary embodiments of various aspects of the present invention will now be described in detail. To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and are not configured to limit the present invention. For those skilled in the art, the present invention can be practiced without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the invention.

[0029] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0030] It should be understood that when describing the structure of a component, when referring to a layer or region as being "above" or "on top of" another layer or region, it can mean that it is directly above the other layer or region, or that it contains other layers or regions between it and the other layer or region. Furthermore, if the component is flipped over, that layer or region will be located "below" or "under" the other layer or region.

[0031] Various modifications and variations can be made to this invention without departing from its spirit or scope, as will be apparent to those skilled in the art. Therefore, this invention is intended to cover modifications and variations falling within the scope of the corresponding claims (the claimed technical solutions) and their equivalents. It should be noted that the embodiments provided in this invention can be combined with each other without contradiction.

[0032] This invention provides a method for manufacturing a display panel and a display panel, which will be described below with reference to the accompanying drawings. Figures 1 to 8 The method for manufacturing the display panel and various embodiments of the display panel are described.

[0033] Please see Figures 1 to 5 , Figure 1 This is a flowchart of a display panel manufacturing method provided in one embodiment of the present invention; Figure 2 This is a schematic diagram of the structure during the fabrication process of a display panel fabrication method provided in one embodiment of the present invention; Figure 3 This is a schematic diagram of the structure during the fabrication process of a display panel fabrication method provided in another embodiment of the present invention; Figure 4 This is a schematic diagram of the structure during the fabrication process of a display panel fabrication method provided in another embodiment of the present invention; Figure 5 This is a schematic diagram of the structure during the fabrication process of a display panel fabrication method provided in another embodiment of the present invention.

[0034] An embodiment of the present invention provides a method for manufacturing a display panel, comprising:

[0035] S110: A first substrate 1 is provided, on which a first electrode 11 is formed, such as... Figure 2 As shown;

[0036] S120: Photoresist 2 is coated on the surface of the first electrode 11 facing away from the first substrate 1 and on the first substrate 1 between the first electrodes 11, such as... Figure 3 As shown;

[0037] S130: The portion of photoresist 2 located between adjacent first electrodes 11 is hardened, such as... Figure 4 As shown;

[0038] S140: Provide a light-emitting element 3 and apply voltage to the light-emitting element 3 to electrically connect the light-emitting element 3 and the first electrode 11, such as... Figure 5 As shown.

[0039] The display panel fabrication method provided in this embodiment of the invention coats photoresist 2 on the side of the first electrode 11 facing away from the first substrate 1 and on the first substrate 1 between the first electrodes 11, and hardens the portion of photoresist 2 located between adjacent first electrodes 11 to increase the hardness of the portion of photoresist 2 between adjacent first electrodes 11. This makes the hardened portion of photoresist 21 less prone to deformation during the pressing step, thus restricting the position of the light-emitting element 3 connected to the first electrode 11. This avoids problems such as position deflection, misalignment, or displacement of the light-emitting element 3 during the pressing process, ensuring the electrical connection effect between the light-emitting element 3 and the first electrode 11 of the first substrate 1, and improving the success rate of transferring the light-emitting element 3.

[0040] In step S110, the first substrate 1 can specifically be a driving substrate. Optionally, the first substrate 1 includes multiple pixel circuits electrically connected to the first electrode 11. Each pixel circuit includes a driving transistor T, and the second electrode is electrically connected to one of the source S and drain D of the driving transistor T. It should be noted that the driving transistor T can specifically be a thin-film transistor (TFT). The TFT includes a gate G, a source S, and a drain D. The materials of the drain D, source S, and gate G can include one or more combinations of molybdenum, titanium, aluminum, copper, etc. The gate G of the TFT is typically used to receive a control signal, causing the TFT to turn on or off under the control of the control signal. One of the source S and drain D of the TFT is connected to the first electrode 11, and then connected to the light-emitting element 3 through the first electrode 11 to control the normal light emission of the light-emitting element 3.

[0041] In step S120, photoresist 2, also known as photoresist or photoresist agent, refers to an etch-resistant thin film material whose solubility changes upon exposure to light or radiation such as ultraviolet light, deep ultraviolet light, electron beams, ion beams, and X-rays. It is a key material in photolithography and is mainly used for the fine patterning of integrated circuits and discrete semiconductor devices. In the embodiments of the present invention, photoresist 2 is used to limit and fix the first electrode 11 and the light-emitting element 3.

[0042] In step S130, the photoresist 2 located between adjacent first electrodes 11 can be hardened by exposure methods such as ultraviolet light irradiation or other hardening methods. The hardened photoresist 21 is not easily deformed and can limit and fix the first electrode 11 and the light-emitting element 3 it surrounds.

[0043] In step S140, the light-emitting element 32 can specifically be a Micro LED (Micro Light Emitting Diode) or a Mini LED (Mini LED). Micro LEDs and Mini LEDs have advantages such as small size, high luminous efficiency, and low power consumption. The size of a Micro LED is less than 50 μm, while the size of a Mini LED is less than 100 μm, enabling clear display of numbers and patterns on smaller display panels. LED chip structures are divided into upright structures, vertical structures, and flip-chip structures. This embodiment of the invention is applicable to LEDs with upright, vertical, and flip-chip structures.

[0044] Optionally, the light-emitting element 3 includes a sapphire substrate, an N-type GaN layer, an active layer, a P-type GaN layer, a metal layer, a P electrode, and an N electrode, wherein at least one of the P electrode and the N electrode is connected to the first electrode 11.

[0045] It should be noted that the pressure in this context refers to a method of applying pressure to the light-emitting element 3 through pneumatic or hydraulic driving means, so that the light-emitting element 3 and the first electrode 11 of the first substrate 1, specifically the driving substrate, are electrically connected.

[0046] Since photoresist 2 is also provided on the side of the first electrode 11 facing away from the first substrate 1, it is used to protect the first electrode 11 when the light-emitting element 3 falls onto the first substrate 1, and to prevent the first electrode 11 and the light-emitting element 3 from colliding directly. However, since the photoresist 2 is not conductive, when it is necessary to make the light-emitting element 3 and the first electrode 11 electrically connected, the photoresist 2 on the side of the first electrode 11 facing away from the first substrate 1 can be squeezed into the area adjacent to the first electrode 11 by heating and pressurizing. Excess photoresist 2 can be removed by cutting or scraping, so that the first electrode 11 and the light-emitting element 3 can make direct contact and achieve electrical connection.

[0047] In some optional embodiments, the step of coating photoresist 2 on the side surface of the first electrode 11 away from the first substrate 1 and on the first substrate 1 between the first electrodes 11 includes coating a semi-solid photoresist 2 on the side surface of the first electrode 11 away from the first substrate 1 and on the first substrate 1 between the first electrodes 11.

[0048] It should be noted that the physical term for a semi-solid state is quasi-solid (which can also be considered a viscous liquid). Although it resembles a solid in some aspects (e.g., it can support its own weight and maintain its shape), semi-solids are also called amorphous solids because, unlike traditional crystalline solids, they are disordered at the microscopic scale. The semi-solid photoresist 2 lacks elasticity; therefore, when the light-emitting element 3 falls onto the photoresist 2, it will not experience rotation or displacement due to the elasticity of the photoresist 2, further improving the transfer accuracy of the light-emitting element 3. Specifically, the semi-solid photoresist 2 can be fabricated through processes such as baking.

[0049] To ensure the protective effect of photoresist 2 on the first electrode 11, the thickness of photoresist 2 is greater than or equal to 8 μm.

[0050] In order to achieve the hardening of the photoresist 2, in some optional embodiments, the step of hardening the portion of the photoresist 2 located between adjacent first electrodes 11 includes: exposing the portion of the photoresist 2 located between adjacent first electrodes 11 through a mask to harden the photoresist 2.

[0051] In this embodiment, exposure specifically refers to irradiating or radiating the photoresist 2 with light sources such as ultraviolet light, excimer laser, electron beam, ion beam, and X-rays, so as to change the chemical and physical properties of the photoresist 2, thereby hardening the photoresist 2, that is, making the photoresist 2 harder and less prone to deformation.

[0052] Optionally, the photoresist 2 is a positive photoresist. The exposed portion of the positive photoresist undergoes a photochemical reaction and dissolves in the developer, while the unexposed portion remains insoluble. That is, in subsequent steps, the exposed portion of the photoresist 2 located between adjacent first electrodes 11 will be removed.

[0053] Please see Figure 8 In some optional embodiments, after providing the light-emitting element 3 and pressing the light-emitting element 3 to connect the light-emitting element 3 and the first electrode 11, the method further includes etching the photoresist 21 of the hardened portion to form a groove C between the first electrode 11.

[0054] It is understandable that the photoresist 21 in the hardened part is etched and developed using a specific developer to form a groove C between the first electrodes 11. Optionally, a light-blocking part can be formed in the groove C. Since the groove C is formed between each first electrode 11 and the light-emitting element 3, the light-blocking part can block the diffused light between adjacent light-emitting elements 3, thus avoiding the problem of light crosstalk.

[0055] Specifically, after etching the photoresist 21 of the hardened portion to form a groove C between the first electrodes 11, the method further includes: forming a light-blocking portion in the groove C, wherein the height of the light-blocking portion is greater than or equal to the height of the light-emitting element 3 in a direction perpendicular to the plane of the first substrate 1.

[0056] By ensuring that the height of the light-blocking part is greater than or equal to the height of the light-emitting element 3, the light-blocking effect of the light-blocking part is greater than that of the light-emitting element 3. Optionally, the light-blocking part can be made of a material with light-blocking effect such as a black matrix.

[0057] Please see Figure 6 and Figure 7 , Figure 6 This is a schematic diagram of the structure during the fabrication process of a display panel fabrication method provided in another embodiment of the present invention; Figure 7 This is a schematic diagram of the fabrication process of a display panel fabrication method according to another embodiment of the present invention. In order to transfer the light-emitting element 3 onto the first substrate 1, in some optional embodiments, the steps of providing the light-emitting element 3 and applying pressure to the light-emitting element 3 to electrically connect the light-emitting element 3 and the first electrode 11 include: providing a second substrate 4, on which the light-emitting element 3 is disposed, such as... Figure 6 As shown; the light-emitting element 3 and the second substrate 4 are separated so that the light-emitting element 3 falls onto the first substrate 1, as shown. Figure 7 As shown; apply pressure to the light-emitting element 3 to electrically connect the light-emitting element 3 and the first electrode 11.

[0058] It should be noted that the light-emitting element 3 can be fixed on the first substrate 1 by means of adhesive layer 41, etc., to separate the light-emitting element 3 from the second substrate 4, so that the light-emitting element 3 falls on the first substrate 1. The adhesive layer 41 can be photosensitive adhesive, which has the characteristic of being decomposed by light. The light-emitting element 3 and the adhesive layer 41 are separated by laser or ultraviolet irradiation and fall onto the first substrate 1. Since the first substrate 1 is provided with photoresist 2 in a semi-solid state and has no resilience, the light-emitting element 3 will not rotate or deviate in position when it falls from the second substrate 4 onto the photoresist 2, which can ensure the accuracy of the landing position.

[0059] To improve the first electrode 11 and the light-emitting element 3, after the steps of providing the light-emitting element 3 and applying pressure to the light-emitting element 3 to make the light-emitting element 3 and the first electrode 11 electrically connected, the method further includes: heating the unetched photoresist 2 to cure the photoresist 2.

[0060] By heating the unetched photoresist 2, the semi-solid photoresist 2 can be transformed into a solid state, making its structural properties more stable and enabling stable support and fixation for the light-emitting element 3 and the first electrode 11.

[0061] This invention also provides a display panel, which is formed by the display panel preparation method described in any of the above embodiments.

[0062] In the manufacturing process of the display panel provided in this embodiment of the invention, photoresist 2 is coated on the side of the first electrode 11 facing away from the first substrate 1 and on the first substrate 1 between the first electrodes 11. The portion of photoresist 2 between adjacent first electrodes 11 is hardened to increase the hardness of the portion of photoresist 2 between adjacent first electrodes 11. In this pressing step, the hardened portion of photoresist 21 is not easily deformed, which can restrict the position of the light-emitting element 3 connected to the first electrode 11. This avoids problems such as position deflection, misalignment, or displacement of the light-emitting element 3 during the pressing process, ensuring the electrical connection effect between the light-emitting element 3 and the first electrode 11 of the first substrate 1, and improving the success rate of transferring the light-emitting element 3.

[0063] The display panel provided in this embodiment of the invention can be applied to mobile phones or any electronic product with display function, including but not limited to the following categories: televisions, laptops, desktop monitors, tablets, digital cameras, smart bracelets, smart glasses, in-vehicle displays, medical devices, industrial control equipment, touch interactive terminals, etc. This embodiment of the invention does not impose any special limitations on these.

[0064] The above are merely specific embodiments of the present invention. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, modules, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the protection scope of the present invention.

[0065] It should also be noted that the exemplary embodiments mentioned in this invention describe methods or systems based on a series of steps or apparatus. However, this invention is not limited to the order of the steps described above; that is, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

Claims

1. A method for manufacturing a display panel, characterized in that, include: A first substrate is provided, on which a first electrode is formed; Photoresist is coated on the side of the first electrode facing away from the first substrate and on the first substrate between the first electrodes; The portion of the photoresist located between adjacent first electrodes is hardened. A light-emitting element is provided, and the light-emitting element is subjected to voltage to electrically connect the light-emitting element and the first electrode.

2. The method for manufacturing a display panel according to claim 1, characterized in that, The step of coating photoresist on the surface of the first electrode facing away from the first substrate and on the first substrate between the first electrodes includes: A semi-solid photoresist is coated on the surface of the first electrode facing away from the first substrate and on the first substrate between the first electrodes.

3. The method for manufacturing a display panel according to claim 1, characterized in that, The thickness of the photoresist is greater than or equal to 8 μm.

4. The method for manufacturing a display panel according to claim 1, characterized in that, The step of hardening the photoresist located between adjacent first electrodes includes: The photoresist located between adjacent first electrodes is exposed using a mask to harden it.

5. The method for manufacturing a display panel according to claim 1, characterized in that, The photoresist is a positive photoresist.

6. The method for manufacturing a display panel according to claim 1, characterized in that, After the steps of providing the light-emitting element and applying pressure to the light-emitting element to electrically connect the light-emitting element and the first electrode, the method further includes: The photoresist in the hardened portion is etched to form a groove between the first electrodes.

7. The method for manufacturing a display panel according to claim 6, characterized in that, After etching the photoresist in the hardened portion to form a groove between the first electrodes, the method further includes: A light-blocking portion is formed within the groove, and the height of the light-blocking portion is greater than or equal to the height of the light-emitting element in a direction perpendicular to the plane of the first substrate.

8. The method for manufacturing a display panel according to claim 1, characterized in that, The step of providing a light-emitting element and applying pressure to the light-emitting element to electrically connect the light-emitting element and the first electrode includes: A second substrate is provided, on which the light-emitting element is disposed; Separate the light-emitting element from the second substrate so that the light-emitting element falls onto the first substrate; The light-emitting element is subjected to pressure to electrically connect the light-emitting element and the first electrode.

9. The method for manufacturing a display panel according to claim 6, characterized in that, After the steps of providing the light-emitting element and applying pressure to the light-emitting element to electrically connect the light-emitting element and the first electrode, the method further includes: The unetched photoresist is heated to cure it.

10. A display panel, characterized in that, The display panel is formed by the display panel manufacturing method according to any one of claims 1 to 9.

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