Method for manufacturing display panel and display panel

Abstract

Embodiments of the present application disclose a display panel manufacturing method and a display panel, and relate to the technical field of display. The display panel manufacturing method comprises forming a first light emitting unit, the first light emitting unit comprising a first light emitting stack, the first light emitting stack comprising a first anode layer, a first cathode layer and a first light emitting layer. A first sub-conductive member is formed on a side of the first cathode layer away from the first anode layer, and the first sub-conductive member is connected with the first cathode layer. A second light emitting unit is formed, the second light emitting unit comprising a second light emitting stack, the second light emitting stack comprising a second anode layer, a second cathode layer and a second light emitting layer. A second sub-conductive member is formed, the second sub-conductive member being connected with the second anode layer. An end surface of the first sub-conductive member on a side away from the first cathode layer and an end surface of the second sub-conductive member protruding from a side of the second light emitting unit are hybridly bonded. In the embodiments of the present application, the first light emitting unit and the second light emitting unit can be connected in series, which is conducive to reducing the heat loss of the display panel.

Description

Technical Field

[0001] The embodiments of this application relate to the field of display technology, and more particularly to a method for manufacturing a display panel and a display panel. Background Technology

[0002] The display panel includes a substrate and multiple light-emitting units, which are spaced apart on one side of the substrate and emit light. The light-emitting units are typically driven by current; within a certain current range, the greater the current flowing through the light-emitting unit, the greater its brightness. To increase the brightness of the light-emitting units, a larger current is usually required to drive them.

[0003] However, when a large current flows through the substrate, the heat loss is greater, which leads to an increase in the power consumption of the display panel. In addition, the greater heat loss will also increase the heat generated by the display panel, which will shorten the lifespan of other components (such as driver chips). Summary of the Invention

[0004] The embodiments of this application provide a method for manufacturing a display panel and a display panel that can reduce the heat loss of the display panel and also reduce the thickness of the display panel.

[0005] On one hand, embodiments of this application provide a method for fabricating a display panel. The method includes: forming a first light-emitting unit, the first light-emitting unit comprising a first light-emitting stack, the first light-emitting stack comprising a first anode layer, a first cathode layer, and a first light-emitting layer, the first anode layer and the first cathode layer being stacked on both sides of the first light-emitting layer, the first anode layer providing holes for the first light-emitting layer, the first cathode layer providing electrons for the first light-emitting layer, and electrons and holes recombinating in the first light-emitting layer to cause the first light-emitting layer to emit light. A first sub-conductive element is formed on the side of the first cathode layer away from the first anode layer, the first sub-conductive element extending along the stacking direction and connected to the first cathode layer, the first sub-conductive element avoiding the light emission path of the first light-emitting unit in the normal direction. A second light-emitting unit is formed, the second light-emitting unit comprising a second light-emitting stack, the second light-emitting stack comprising a second anode layer, a second cathode layer, and a second light-emitting layer, the second anode layer and the second cathode layer being stacked on both sides of the second light-emitting layer, the second anode layer providing holes for the second light-emitting layer, the second cathode layer providing electrons for the second light-emitting layer, and electrons and holes recombinating in the second light-emitting layer to cause the second light-emitting layer to emit light. A second sub-conductive element is formed, extending along the stacking direction and protruding from the second light-emitting unit. The second sub-conductive element is connected to the second anode layer, and avoids the light emission path of the second light-emitting unit in the normal direction. The end face of the first sub-conductive element away from the first cathode layer and the end face of the second sub-conductive element protruding from the second anode layer are mixed and bonded.

[0006] In the embodiments of this application, the end face of the first sub-conductive element away from the first cathode layer and the end face of the second sub-conductive element protruding from the second light-emitting unit are mixed and bonded, so that the first light-emitting unit and the second light-emitting unit can be stacked along the thickness direction of the substrate, and the first cathode layer and the second anode layer can be connected in series through the first sub-conductive element and the second sub-conductive element, so that the current can drive the first light-emitting unit and the second light-emitting unit to emit light together.

[0007] The stacked first and second light-emitting units can form a light-emitting pixel. Understandably, when the current value is constant, the combined illumination of the first and second light-emitting units can increase the brightness of the light-emitting pixel; when the brightness of the light-emitting pixel is constant, a smaller current can be set for the first and second light-emitting units.

[0008] By using the above setting method, a smaller current value can make the light-emitting pixels reach the set brightness. This reduces the current driving the light-emitting unit while ensuring the brightness of the light-emitting pixels, thereby reducing heat loss and power consumption of the display panel. Furthermore, reducing heat loss also reduces the heat generated by the display panel, minimizing the impact of heat on other components (such as the driver chip), and thus extending the lifespan of the display panel.

[0009] Furthermore, by setting a smaller current value to drive multiple stacked light-emitting units while keeping the parasitic resistance of the substrate constant, the voltage drop of the substrate can be reduced, thereby improving the reliability of the substrate driving the light-emitting units to emit light.

[0010] By using a hybrid bonding method to connect the first sub-conductive component and the second sub-conductive component, there is no need to set a bonding layer between the first and second sub-conductive components. The first and second sub-conductive components can be exposed on the first and second transparent dielectric layers, which helps to reduce the thickness of the display panel.

[0011] Understandably, after the first sub-conductive component and the second sub-conductive component are bonded together, the first sub-conductive component and the second sub-conductive component can be connected into a whole. In this way, the connection reliability of the first sub-conductive component and the second sub-conductive component can be improved, thereby improving the connection reliability of the first light-emitting unit and the second light-emitting unit.

[0012] In some possible implementations, after forming a first sub-conductive element on the side of the first cathode layer away from the first anode layer, the method of fabricating the display panel further includes: forming a first transparent dielectric layer on the side of the first light-emitting unit near the first sub-conductive element, with the first sub-conductive element embedded within the first transparent dielectric layer, and the end face of the first sub-conductive element on the side away from the first light-emitting unit being flush with the surface of the first transparent dielectric layer on the side away from the first light-emitting unit. After forming a second sub-conductive element, the method of fabricating the display panel further includes: forming a second transparent dielectric layer, with the second sub-conductive element embedded within the second transparent dielectric layer, and the end face of the second sub-conductive element protruding from the side of the second anode layer being flush with the surface of the second transparent dielectric layer on the side away from the second anode layer. The method of fabricating the display panel further includes: mixing and bonding the surface of the first transparent dielectric layer on the side away from the first light-emitting unit and the surface of the second transparent dielectric layer on the side away from the second anode layer.

[0013] The first transparent dielectric layer and the second transparent dielectric layer are connected by a hybrid bonding method, which eliminates the need for a bonding layer between the first transparent dielectric layer and the second transparent dielectric layer, thus reducing the thickness of the display panel.

[0014] Understandably, after the first transparent dielectric layer and the second transparent dielectric layer are mixed and bonded, the first transparent dielectric layer and the second transparent dielectric layer can be connected into a whole. In this way, the connection reliability of the first transparent dielectric layer and the second transparent dielectric layer can be improved, thereby improving the connection reliability of the first light-emitting unit and the second light-emitting unit.

[0015] In some possible implementations, forming the first light-emitting unit includes: forming a first light-emitting stack on one side of a first substrate, with a first anode layer located away from the first substrate relative to a first cathode layer; forming a first transparent insulating layer, the first transparent insulating layer including a first insulating portion, the first insulating portion being stacked on the side of the first light-emitting stack away from the first substrate, the first insulating portion having a first through-hole exposing the first light-emitting stack; forming a first metallic reflective portion, the first metallic reflective portion including a first sub-reflective portion, the first sub-reflective portion being stacked on the side of the first insulating portion away from the light-emitting stack, the first sub-reflective portion being connected to the first anode layer through the first through-hole; and after forming the first light-emitting unit, the method for manufacturing the display panel further includes: connecting the first sub-reflective portion to the anode contacts of the substrate.

[0016] The first sub-reflective part is connected to the first anode layer, and the first sub-reflective part is connected to the anode contact of the substrate, so that the first anode layer can be connected to the anode contact of the substrate.

[0017] Understandably, the first metal reflective portion not only conducts electricity but also reflects light. The first sub-reflective portion is connected to the anode contact of the substrate, allowing the first sub-reflective portion to be located between the first light-emitting layer and the substrate. This enables the first light-emitting layer to reflect light emitted from it to the side of the first light-emitting layer away from the substrate, thereby increasing the luminous intensity of the first light-emitting unit in the normal direction.

[0018] The normal direction of the first light-emitting unit is the same as or approximately the same as the thickness direction of the substrate. The light emission path of the first light-emitting unit in the normal direction is the main light emission path of the first light-emitting unit. Increasing the luminous intensity of the first light-emitting unit in the normal direction is beneficial to improving the brightness of the display panel.

[0019] In some possible implementations, the first transparent insulating layer further includes a second insulating portion located on the side of the first light-emitting stack and connected to the first insulating portion. The first metallic reflective portion further includes a second sub-reflective portion located on the side of the second insulating portion away from the light-emitting stack and connected to the first sub-reflective portion.

[0020] Understandably, the second sub-reflective portion can surround the first light-emitting stack, thereby reflecting the light emitted by the first light-emitting layer to the side of the first light-emitting layer away from the substrate, which is beneficial to increasing the light-emitting intensity of the first light-emitting unit in the normal direction, thereby improving the brightness of the display panel.

[0021] In some possible implementations, before forming the first sub-conductive element, the method for fabricating the display panel further includes: forming a first transparent conductive layer on the side of the first light-emitting stack away from the substrate; the first transparent conductive layer and the first cathode layer are connected; and the orthogonal projection of the first transparent conductive layer on the substrate covers the orthogonal projection of the first light-emitting stack on the substrate. Forming the first sub-conductive element includes: forming the first sub-conductive element on the side of the first transparent conductive layer away from the first light-emitting stack.

[0022] Understandably, the first transparent conductive layer is stacked on the side of the first cathode ohmic contact layer away from the first cathode layer and connected to the first cathode ohmic contact layer, so that the first transparent conductive layer can be connected to the first cathode layer through the first cathode ohmic contact layer, thereby reducing the resistance between the first transparent conductive layer and the first cathode layer. The first transparent conductive layer is constructed as a transparent structure, which can reduce the obstruction of light emitted by the first light-emitting unit caused by the first transparent conductive layer.

[0023] The orthographic projection of the first transparent conductive layer on the substrate overlaps the orthographic projection of the first light-emitting stack on the substrate, allowing the edge region of the first transparent conductive layer to protrude beyond the first light-emitting stack. A first sub-conductive element may be formed where the first transparent conductive layer protrudes beyond the edge region of the first light-emitting stack to avoid obstructing the light emission path of the first light-emitting unit in the emitting direction.

[0024] In some possible implementations, forming the second light-emitting unit includes: forming a second light-emitting stack on one side of the second substrate, with the second anode layer located away from the second substrate relative to the second cathode layer; forming a second transparent conductive layer including a first conductive portion, the orthographic projection of the first conductive portion onto the second substrate surrounding the orthographic projection of the second light-emitting stack onto the second substrate, and the first conductive portion being connected to the second anode layer; and forming a second sub-conductive element includes: forming the second sub-conductive element on the side of the first conductive portion away from the second substrate.

[0025] Understandably, a second sub-conductive element is formed on the side of the first conductive portion away from the second substrate, allowing the second sub-conductive element to be connected through the first conductive portion and the second anode layer. Furthermore, the orthographic projection of the first conductive portion onto the second substrate surrounds the orthographic projection of the second light-emitting stack onto the second substrate, enabling the first conductive portion to avoid the light emission path of the second light-emitting unit in the normal direction. The second sub-conductive element is located on the side of the second conductive portion away from the second substrate, allowing the second sub-conductive element to avoid the light emission path of the second light-emitting unit in the normal direction.

[0026] In some possible implementations, before forming the second transparent conductive element, the method for fabricating the display panel further includes forming a second transparent insulating layer. The second transparent insulating layer includes a fourth insulating portion, a fifth insulating portion, and a sixth insulating portion. The fourth insulating portion is stacked on the side of the second substrate near the second light-emitting stack and surrounds the second light-emitting stack. The fifth insulating portion is disposed on the side of the second light-emitting stack. The sixth insulating portion is stacked on the side of the second light-emitting stack away from the second substrate. The fifth insulating portion connects the fourth and sixth insulating portions. A second through-hole is formed on the sixth insulating portion, exposing the second light-emitting stack. A first sublayer of the second transparent dielectric layer is formed, and a first conductive portion is stacked on the side of the first sublayer away from the second substrate.

[0027] Understandably, the first sublayer of the second transparent dielectric layer is formed after the formation of the second transparent insulating layer and before the formation of the second transparent conductive layer, so that the first sublayer can be stacked between the first conductive portion and the first insulating portion, that is, the first sublayer can raise the first conductive portion.

[0028] This reduces the length of the second sub-conductive component connected to the first conductive part, thereby reducing the resistance of the second sub-conductive component and simplifying its fabrication, which in turn improves the production yield of the display panel.

[0029] In some possible implementations, before forming the first sublayer of the second transparent dielectric layer, the method for fabricating the display panel further includes: forming a second transparent insulating layer, the second transparent insulating layer including a third insulating portion, a fourth insulating portion, and a fifth insulating portion, the third insulating portion being stacked on the side of the second light-emitting stack away from the second substrate, the fourth insulating portion being disposed on the side of the second light-emitting stack, and the fifth insulating portion being stacked on the side of the second substrate close to the second light-emitting stack and surrounding the second light-emitting stack, the fourth insulating portion connecting the third insulating portion and the fifth insulating portion. A second metallic reflective portion is formed, the second metallic reflective portion being located between the fifth insulating portion and the first conductive portion along the stacking direction, and the second metallic reflective portion being located on the side of the fourth insulating portion away from the second light-emitting stack.

[0030] The second metal reflective portion is located on the side of the sixth insulating portion away from the second light-emitting stack, enabling it to reflect light emitted from the second light-emitting layer. The second metal reflective portion is embedded within the first sub-layer, reducing the mutual interference between the second metal reflective portion and the second transparent conductive layer.

[0031] Understandably, the second metal reflector and the second sub-conductive element are arranged along the thickness direction so that the second metal reflector and the second sub-conductive element can jointly reflect the light emitted by the second light-emitting layer, reduce the light crosstalk between two adjacent second light-emitting units, and help improve the luminous brightness of the second light-emitting unit in the emitting direction.

[0032] On the other hand, embodiments of this application provide a display panel. The display panel is a display panel fabricated by the method described above. The display panel includes a substrate and a plurality of light-emitting pixels. The plurality of light-emitting pixels are disposed on one side of the substrate along the thickness direction of the substrate, and the plurality of light-emitting pixels are spaced apart. Each light-emitting pixel includes a plurality of light-emitting units, a first sub-conductive element, and a second sub-conductive element. The plurality of light-emitting units are stacked along the thickness direction of the substrate, and two light-emitting units disposed adjacent to each other along the thickness direction of the substrate include a first light-emitting unit and a second light-emitting unit. The first light-emitting unit includes a first light-emitting stack, which includes a first anode layer, a first cathode layer, and a first light-emitting layer. The first anode layer and the first cathode layer are stacked on both sides of the first light-emitting layer. The second light-emitting unit includes a second light-emitting stack, which includes a second anode layer, a second cathode layer, and a second light-emitting layer. The second anode layer and the second cathode layer are stacked on both sides of the second light-emitting layer. The first sub-conductive element extends along the stacking direction and is connected to the first cathode layer. The first sub-conductive element avoids the light emission path of the first light-emitting unit in the normal direction. The second sub-conductive element extends along the stacking direction and protrudes from the second anode layer. The second sub-conductive element is connected to the second anode layer and avoids the light emission path of the second light-emitting unit in the normal direction. The end face of the first sub-conductive element away from the first cathode layer and the end face of the second sub-conductive element protruding from the second anode layer are mixed and bonded.

[0033] In the embodiments of this application, the end face of the first sub-conductive element away from the first cathode layer and the end face of the second sub-conductive element protruding from the second light-emitting unit are mixed and bonded, so that the first light-emitting unit and the second light-emitting unit can be stacked along the thickness direction of the substrate, and the first cathode layer and the second anode layer can be connected in series through the first sub-conductive element and the second sub-conductive element, so that the current can drive the first light-emitting unit and the second light-emitting unit to emit light together.

[0034] The stacked first and second light-emitting units can form a light-emitting pixel. Understandably, when the current value is constant, the combined illumination of the first and second light-emitting units can increase the brightness of the light-emitting pixel; when the brightness of the light-emitting pixel is constant, a smaller current can be set for the first and second light-emitting units.

[0035] By using the above setting method, a smaller current value can make the light-emitting pixels reach the set brightness. This reduces the current driving the light-emitting unit while ensuring the brightness of the light-emitting pixels, thereby reducing heat loss and power consumption of the display panel. Furthermore, reducing heat loss also reduces the heat generated by the display panel, minimizing the impact of heat on other components (such as the driver chip), and thus extending the lifespan of the display panel.

[0036] Furthermore, by setting a smaller current value to drive multiple stacked light-emitting units while keeping the parasitic resistance of the substrate constant, the voltage drop of the substrate can be reduced, thereby improving the reliability of the substrate driving the light-emitting units to emit light.

[0037] By using a hybrid bonding method to connect the first sub-conductive component and the second sub-conductive component, there is no need to set a bonding layer between the first and second sub-conductive components. The first and second sub-conductive components can be exposed on the first and second transparent dielectric layers, which helps to reduce the thickness of the display panel.

[0038] Understandably, after the first sub-conductive component and the second sub-conductive component are bonded together, the first sub-conductive component and the second sub-conductive component can be connected into a whole. In this way, the connection reliability of the first sub-conductive component and the second sub-conductive component can be improved, thereby improving the connection reliability of the first light-emitting unit and the second light-emitting unit.

[0039] In some possible implementations, the display panel further includes a first transparent dielectric layer and a second transparent dielectric layer. The first transparent dielectric layer is stacked on the side of the first light-emitting unit near the first sub-conductive member. The first sub-conductive member is embedded within the first transparent dielectric layer, and the end face of the first sub-conductive member away from the first light-emitting unit is flush with the surface of the first transparent dielectric layer away from the first light-emitting unit. The second transparent dielectric layer is stacked on the side of the first transparent dielectric layer away from the substrate. The second sub-conductive member is embedded within the second transparent dielectric layer, and the end face of the second sub-conductive member protruding from the second anode layer is flush with the surface of the second transparent dielectric layer away from the second anode layer. The first and second transparent dielectric layers are co-bonded.

[0040] The first transparent dielectric layer and the second transparent dielectric layer are connected by a hybrid bonding method, which eliminates the need for a bonding layer between the first transparent dielectric layer and the second transparent dielectric layer, thus reducing the thickness of the display panel.

[0041] Understandably, after the first transparent dielectric layer and the second transparent dielectric layer are mixed and bonded, the first transparent dielectric layer and the second transparent dielectric layer can be connected into a whole. In this way, the connection reliability of the first transparent dielectric layer and the second transparent dielectric layer can be improved, thereby improving the connection reliability of the first light-emitting unit and the second light-emitting unit. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of a display device provided in some embodiments of this application.

[0043] Figure 2 This is a schematic diagram of the display panel under some possible conditions.

[0044] Figure 3A flowchart illustrating the process steps of a method for fabricating a display panel according to some embodiments of this application.

[0045] Figure 4 This is a schematic diagram of the structure of a first light-emitting stack provided in some embodiments of this application.

[0046] Figure 5 A flowchart illustrating the process steps of a method for fabricating a first light-emitting unit provided in some embodiments of this application.

[0047] Figure 6 This is a schematic diagram showing the positional relationship between the first light-emitting stack and the first transparent insulating layer, provided for some embodiments of this application.

[0048] Figure 7 This is a schematic diagram showing the positional relationship between the first metal reflective part, the first transparent insulating layer, and the first light-emitting stack provided in some embodiments of this application.

[0049] Figure 8 This is a schematic diagram showing the positional relationship between the third transparent dielectric layer, the metal connector, and the first light-emitting stack provided in some embodiments of this application.

[0050] Figure 9 This is a schematic diagram showing the positional relationship between the first substrate, the first light-emitting unit, and the substrate provided in some embodiments of this application.

[0051] Figure 10 This is a schematic diagram showing the positional relationship between the first light-emitting unit and the substrate provided in some embodiments of this application.

[0052] Figure 11 This is a schematic diagram showing the positional relationship between the first sub-conductive element and the first light-emitting unit provided in some embodiments of this application.

[0053] Figure 12 This is a schematic diagram of the structure of a second light-emitting stack provided in some embodiments of this application.

[0054] Figure 13 A flowchart illustrating the process steps of a method for fabricating a second light-emitting unit provided in some embodiments of this application.

[0055] Figure 14 This is a schematic diagram showing the positional relationship between the second substrate and the second initial stack body provided in some embodiments of this application.

[0056] Figure 15 A schematic diagram showing the positional relationship between the second transparent insulating layer and the second light-emitting stack provided in some embodiments of this application.

[0057] Figure 16 This is a schematic diagram showing the positional relationship between the second transparent conductive layer, the second transparent insulating layer, and the second light-emitting stack provided in some embodiments of this application.

[0058] Figure 17 This is a schematic diagram showing the positional relationship between the second transparent conductive layer, the second transparent insulating layer, and the second light-emitting stack, provided for other embodiments of this application.

[0059] Figure 18 This is a schematic diagram showing the positional relationship between the second transparent conductive layer, the second transparent insulating layer, and the second light-emitting stack, provided in some embodiments of this application.

[0060] Figure 19 This is a schematic diagram showing the positional relationship between the second sub-conductive element, the second transparent conductive layer, and the second light-emitting stack, as provided in some embodiments of this application.

[0061] Figure 20 This is a schematic diagram showing the positional relationship between the second sub-conductive element, the second transparent conductive layer, and the second light-emitting stack, as provided in other embodiments of this application.

[0062] Figure 21 This is a schematic diagram showing the positional relationship between the second sub-conductive element, the second transparent conductive layer, and the second light-emitting stack, provided in some embodiments of this application.

[0063] Figure 22 This is a schematic diagram showing the positional relationship between a first light-emitting unit, a second light-emitting unit, a second substrate, and a substrate provided in some embodiments of this application.

[0064] Figure 23 This is a schematic diagram showing the positional relationship between the first light-emitting unit, the second light-emitting unit, the second substrate, and the substrate provided in other embodiments of this application.

[0065] Figure 24 This is a schematic diagram showing the positional relationship between the first light-emitting unit, the second light-emitting unit, the second substrate, and the substrate, provided for some embodiments of this application.

[0066] Figure 25 This is a schematic diagram showing the positional relationship between the first light-emitting unit, the second light-emitting unit, and the substrate provided in some embodiments of this application.

[0067] Figure 26 This is a schematic diagram showing the positional relationship between the first light-emitting unit, the second light-emitting unit, and the substrate provided in other embodiments of this application.

[0068] Figure 27 This is a schematic diagram showing the positional relationship between the first light-emitting unit, the second light-emitting unit, and the substrate, provided for some embodiments of this application.

[0069] Figure 28 This is a schematic diagram showing the positional relationship between the first light-emitting unit, the second light-emitting unit, and the cathode metal provided in some embodiments of this application.

[0070] Figure 29This is a schematic diagram showing the positional relationship between the first light-emitting unit, the second light-emitting unit, and the cathode metal provided in other embodiments of this application.

[0071] Figure 30 This is a schematic diagram showing the positional relationship between the first light-emitting unit, the second light-emitting unit, and the cathode metal, provided for some embodiments of this application.

[0072] Figure 31 This is a schematic diagram showing the positional relationship between the substrate, light-emitting pixels, and microlenses provided in some embodiments of this application.

[0073] Figure 32 This is a schematic diagram showing the positional relationship between the substrate, light-emitting pixels, and microlenses provided for other embodiments of this application.

[0074] Figure 33 This is a schematic diagram showing the positional relationship between the substrate, the light-emitting pixel, and the microlens provided in some embodiments of this application.

[0075] Explanation of icon numbers: 300 - Display device; 310 - Housing; 320 - Bracket; 200 - Display panel; 201 - First transparent dielectric layer; 202 - Second transparent dielectric layer; 2021 - First sublayer; 2022 - Second sublayer; 203 - Third transparent dielectric layer; 204 - Fourth transparent dielectric layer; 205 - Cathode metal; 206 - Metal connector; 207 - Microlens; 210 - Substrate; 211 - Anode contact; 220 - Light-emitting pixel; 230 - Light-emitting unit; 231 - First light-emitting unit; 2311 - First light-emitting pixel Stacked bodies, 2311a-first anode layer, 2311b-first cathode layer, 2311c-first light-emitting layer, 2311d-first anode ohmic contact layer, 2311e-first cathode ohmic contact layer, 232-second light-emitting unit, 2321-second light-emitting stacked body, 2321a-second anode layer, 2321b-second cathode layer, 2321c-second light-emitting layer, 2321d-second anode ohmic contact layer, 2321e-second cathode ohmic contact layer, 23211-second initial stacked body, 232 1aa - Second initial anode layer, 2321bb - Second initial cathode layer, 2321cc - Second initial light-emitting layer, 2321dd - Second initial anode ohmic contact layer, 2321ee - Second initial cathode ohmic contact layer, 233 - First metal reflector, 2331 - First sub-reflector, 2332 - Second sub-reflector, 2333 - Third sub-reflector, 234 - First transparent conductive layer, 235 - First transparent insulating layer, 2351 - First insulating layer, 2352 - Second insulating layer, 2353 - Third Insulating portion, 236-Second transparent conductive layer, 2361-First conductive portion, 2362-Second conductive portion, 2363-Third conductive portion, 237-Second transparent insulating layer, 2371-Fourth insulating portion, 2372-Fifth insulating portion, 2373-Sixth insulating portion, 238-Second metal reflective portion, 241-First sub-conductive component, 242-Second sub-conductive component, 251-Third transparent conductive layer, 401-First substrate, 402-Second substrate, P1-First through hole, P2-Second through hole, Z-Thickness direction. Detailed Implementation

[0076] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all possible embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0077] like Figure 1As shown, an embodiment of this application provides a display device 300, which has an image display function. The display device 300 may include a display panel 200 and a housing 310, wherein the display panel 200 is used to display image information.

[0078] The display panel 200 can be a light-emitting diode (LED) display panel, for example, it can be one of a micro light-emitting diode (Micro LED) display panel and a mini light-emitting diode (Mini LED) display panel.

[0079] The display panel 200 includes a light-emitting side and a backlight side that are arranged opposite to each other. The housing 310 can be disposed on the backlight side and connected to the display panel 200, so that the housing 310 can protect the display panel 200 and reduce the impact of the housing 310 on the light emitting side of the display panel 200.

[0080] like Figure 1 As shown, the display device 300 may also include a bracket 320, which is connected to the side of the housing 310 that is close to the ground when in use, and serves to support the housing 310 and the display panel 200.

[0081] The embodiments of this application do not further limit other components of the display device 300; the display panel 200 is described below as an example.

[0082] In some examples, such as Figure 2 As shown, the display panel 200 may include a substrate 210 and a plurality of light-emitting pixels 220. The plurality of light-emitting pixels 220 are disposed on one side of the substrate 210 along the thickness direction Z of the substrate 210, and the plurality of light-emitting pixels 220 are spaced apart.

[0083] Understandably, each light-emitting pixel 220 can emit light independently. Multiple light-emitting pixels 220 may include red, green, and blue light-emitting pixels, with the red pixels emitting red light, the green pixels emitting green light, and the blue pixels emitting blue light. By adjusting the brightness of the red, green, and blue light-emitting pixels, the display panel 200 can achieve full-color display.

[0084] The substrate 210 can be one of a printed circuit board (PCB), a flexible printed circuit (FPC), a glass substrate, or a complementary metal-oxide-semiconductor (CMOS) driving backplane. The embodiments of this application do not further limit the specific form of the substrate 210.

[0085] The substrate 210 is provided with an anode contact 211 and a cathode contact (not shown in the figure), which are respectively connected to the light-emitting pixel 220. This allows current to flow through the light-emitting pixel 220, thereby enabling the light-emitting pixel 220 to emit light. The substrate 210 may also be provided with a driver chip or other control devices for driving the light-emitting pixel 220 to emit light.

[0086] For example, the light-emitting unit 230 can be driven digitally, that is, the pulse width modulation (PWM) method can be used to adjust the pulse width of the light-emitting unit 230's turn-on time, thereby adjusting the intensity of the light emitted by the light-emitting pixel 220.

[0087] Understandably, the light-emitting unit 230 is driven by current. Within a certain current range, the greater the current flowing through the light-emitting unit 230, the greater its luminous brightness. To increase the luminous brightness of the light-emitting unit, a larger current is usually required to drive the light-emitting unit 230.

[0088] However, when a large current flows through the substrate 210, the heat loss is greater, which leads to an increase in the power consumption of the display panel 200. In addition, the greater heat loss will also increase the heat generated by the display panel 200, which will shorten the lifespan of other components (such as the driver chip disposed on the substrate 210).

[0089] Furthermore, due to the parasitic resistance of the substrate 210, an increase in current will lead to an increase in the voltage drop of the substrate 210, affecting the reliability of the substrate 210 in driving the light-emitting unit 230 to emit light.

[0090] For example, when the area of ​​the display panel 200 is 1 square centimeter and the current density is 10 amperes per square centimeter, a parasitic resistance of 0.1 ohms will produce a voltage drop of 1 volt. If the power supply voltage of the display panel 200 is 5V, the voltage drop will account for 20% of the power supply voltage, affecting the light-emitting reliability of the light-emitting unit 230.

[0091] Furthermore, as the size of the light-emitting unit 230 increases, the current density will increase further, and the voltage drop caused by parasitic resistance will also be greater, which will have a more significant impact on the light emission of the light-emitting unit 230.

[0092] Based on this, embodiments of this application provide a method for fabricating a display panel. The display panel fabricated by this method has advantages such as low power consumption, high brightness, and small thickness. The fabrication method for the display panel is illustrated below with examples.

[0093] In some examples, such as Figure 3 As shown, the method for manufacturing the display panel includes: Step S1: Form a first light-emitting unit. The first light-emitting unit includes a first light-emitting stack, which includes a first anode layer, a first cathode layer, and a first light-emitting layer. The first anode layer and the first cathode layer are stacked on both sides of the first light-emitting layer. The first anode layer is used to provide holes for the first light-emitting layer, and the first cathode layer is used to provide electrons for the first light-emitting layer. Electrons and holes recombine in the first light-emitting layer to make the first light-emitting layer emit light.

[0094] like Figure 4 As shown, the first light-emitting layer 2311c can be a multiple quantum well (MQW) structure. When the light-emitting pixel 220 is a blue or green light-emitting pixel, the material of the first light-emitting layer 2311c can include indium gallium nitride (InGaN). When the light-emitting pixel 220 is a red light-emitting pixel, the material of the first light-emitting layer 2311c can include aluminum gallium indium phosphide (AlGaInP). Alternatively, the first light-emitting layer 2311c can also include other materials; the embodiments of this application do not further limit the material of the first light-emitting layer 2311c.

[0095] The first anode layer 2311a can be a P-type semiconductor layer, enabling it to provide holes for the first light-emitting layer 2311c. When the light-emitting pixel 220 is a blue or green light-emitting pixel, the material of the first anode layer 2311a can include P-type gallium nitride. When the light-emitting pixel 220 is a red light-emitting pixel, the material of the first anode layer 2311a can include P-type aluminum gallium indium phosphide. Alternatively, the first anode layer 2311a can also include other materials; the embodiments of this application do not further limit the material of the first anode layer 2311a.

[0096] The first cathode layer 2311b can be an N-type semiconductor layer, enabling it to provide electrons to the first light-emitting layer 2311c. When the light-emitting pixel 220 is a blue or green light-emitting pixel, the material of the first cathode layer 2311b can include N-type gallium nitride. When the light-emitting pixel 220 is a red light-emitting pixel, the material of the first cathode layer 2311b can include N-type aluminum gallium indium phosphide. Alternatively, the first cathode layer 2311b can also include other materials; the embodiments of this application do not further limit the material of the first cathode layer 2311b.

[0097] Continue to refer to Figure 4 The first light-emitting stack 2311 may further include a first ohmic contact layer, which includes a first anode ohmic contact layer 2311d and a first cathode ohmic contact layer 2311e. The first anode ohmic contact layer 2311d is stacked on the side of the first anode layer 2311a away from the first cathode layer 2311b, and the first cathode ohmic contact layer 2311e is stacked on the side of the first cathode layer 2311b away from the first anode layer 2311a.

[0098] Understandably, the first ohmic contact layer (including the first anode ohmic contact layer 2311d and the first cathode ohmic contact layer 2311e) has good conductivity and can reduce the resistance between the first anode layer 2311a and the first cathode layer 2311b and other film layers.

[0099] Alternatively, the first light-emitting stack 2311 may not include the first ohmic contact layer to simplify the first light-emitting stack 2311. The embodiments of this application use the example of the first light-emitting stack 2311 including the first ohmic contact layer for further illustration.

[0100] The following example illustrates the preparation method of the first light-emitting unit 231.

[0101] In some examples, such as Figure 5 As shown, forming the first light-emitting unit (i.e., step S1) includes: In step S11, a first light-emitting stack is formed on one side of the first substrate, with the first anode layer being farther away from the first substrate relative to the first cathode layer.

[0102] For example, a first initial stack (not shown) may be formed on one side of the first substrate 401. The first initial stack includes a first initial cathode ohmic contact layer, a first initial cathode layer, a first initial light-emitting layer, a first initial anode layer, and a first initial anode ohmic contact layer stacked together. Along the direction from the first substrate 401 to the first initial stack, the first initial cathode ohmic contact layer, the first initial cathode layer, the first initial light-emitting layer, the first initial anode layer, and the first initial anode ohmic contact layer are sequentially moved away from the first substrate 401.

[0103] The first initial stack can be formed on one side of the first substrate 401 using chemical vapor deposition (CVD) or physical vapor deposition (PVD) processes, or other processes can be used to form the first initial stack on one side of the first substrate 401. The embodiments of this application do not further limit the process for forming the first initial stack.

[0104] After the first initial stack is formed, the first initial stack can be patterned to form a plurality of first light-emitting stacks 2311 spaced apart (see [reference]). Figure 4 For example, the first initial stack can be patterned using photolithography or ion beam etching, or other processes can be used to pattern the first initial stack, which is not further limited by the embodiments of this application.

[0105] Understandably, the first initial anode layer is located away from the first substrate 401 relative to the first initial cathode layer, such that the first anode layer 2311a is located away from the first substrate 401 relative to the first cathode layer 2311b.

[0106] Step S12: A first transparent insulating layer is formed. The first transparent insulating layer includes a first insulating portion. The first insulating portion is stacked on the side of the first light-emitting stack away from the first substrate. A first through hole is formed on the first insulating portion, and the first through hole exposes the first light-emitting stack.

[0107] like Figure 6 As shown, the first transparent insulating layer 235 can cover the surface of the first light-emitting stack 2311 away from the first substrate 401 and the side surface of the first light-emitting stack 2311. The first transparent insulating layer 235 can play a role in electrical isolation, reducing the risk of short circuit between the first light-emitting stack 2311 and other film layers.

[0108] The material of the first transparent insulating layer 235 may include oxides, such as silicon oxide. Alternatively, the material of the first transparent insulating layer 235 may also include nitrides, such as silicon nitride. It is understood that the first transparent insulating layer 235 may also include other materials besides oxides and nitrides, and the embodiments of this application do not further limit the material of the first transparent insulating layer 235.

[0109] For example, a first initial transparent insulating layer can be formed first to cover the first light-emitting stack 2311, and then a first through hole P1 can be opened on the first initial transparent insulating layer to form the first transparent insulating layer 235.

[0110] The first initial transparent insulating layer can be formed using CVD or PVD processes, or other processes. The embodiments of this application do not further limit the process for forming the first transparent insulating layer 235.

[0111] The first via P1 can be formed on the first initial transparent insulating layer using photolithography or ion beam etching processes to create the first transparent insulating layer 235. The embodiments of this application do not further limit the process for forming the first via P1.

[0112] Continue to refer to Figure 6 For example, the first transparent insulating layer 235 may include a first insulating portion 2351, a second insulating portion 2352 and a third insulating portion 2353.

[0113] A first insulating portion 2351 is stacked on the side of the first light-emitting stack 2311 away from the first substrate 401. A first through-hole P1 is formed on the first insulating portion 2351, allowing the first light-emitting stack 2311 to be exposed. Understandably, the first through-hole P1 can expose the first anode ohmic contact layer 2311d of the first light-emitting stack 2311, allowing other components to be connected through the first anode ohmic contact layer 2311d and the first anode layer 2311a.

[0114] The second insulating portion 2352 is disposed on the side of the first light-emitting stack 2311 and connected to the first insulating portion 2351. The third insulating portion 2353 is stacked on the side of the first substrate 401 near the first light-emitting stack 2311 and surrounds the first light-emitting stack 2311. The third insulating portion 2353 is connected to the second insulating portion 2352.

[0115] Step S13: A first metal reflective portion is formed. The first metal reflective portion includes a first sub-reflective portion. The first sub-reflective portion is stacked on the side of the first insulating portion away from the light-emitting stack. The first sub-reflective portion is connected to the first anode layer through a first through hole.

[0116] For example, the material of the first metal reflective part 233 may include gold, silver or copper, or the first metal reflective part 233 may also include other metal materials. The embodiments of this application do not further limit the material of the first metal reflective part 233.

[0117] The first metal reflective portion 233 is stacked on the side of the first transparent insulating layer 235 away from the first light-emitting stack 2311, so that the first transparent insulating layer 235 can electrically isolate the first light-emitting stack 2311 and the first metal reflective portion 233.

[0118] For example, a first initial metal reflective layer may be formed, which covers a plurality of first light-emitting stacks 2311. The first initial metal reflective layer is then patterned to form a plurality of first metal reflective portions 233 spaced apart, which can be understood to correspond to one first metal reflective portion 233 and one first light-emitting stack 2311.

[0119] The first initial metal reflective layer can be formed using CVD or PVD processes, or other processes. The embodiments of this application do not further limit the process for forming the first metal reflective part 233.

[0120] The first initial metal reflective layer can be patterned using photolithography or ion beam etching processes, or other processes can be used to pattern the first initial metal reflective layer. The embodiments of this application do not further limit this.

[0121] Continue to refer to Figure 7 For example, the first metal reflective part 233 may include a first sub-reflective part 2331, a second sub-reflective part 2332 and a third sub-reflective part 2333.

[0122] The first sub-reflective portion 2331 is stacked on the side of the first insulating portion 2351 away from the first light-emitting stack 2311, and is connected to the first anode ohmic contact layer 2311d through the first through hole P1. In this way, the first sub-reflective portion 2331 can be connected to the first anode layer 2311a through the first anode ohmic contact layer 2311d, thereby reducing the resistance between the first sub-reflective portion 2331 and the first anode layer 2311a.

[0123] The second sub-reflective portion 2332 is located on the side of the second insulating portion 2352 away from the first light-emitting stack 2311 and is connected to the first sub-reflective portion 2331. The third sub-reflective portion 2333 is stacked on the side of the third insulating portion 2353 away from the first substrate 401, and the third sub-reflective portion 2333 surrounds the first light-emitting stack 2311.

[0124] Understandably, the first transparent insulating layer 235 can isolate the first metal reflective part 233 and other film layers in the first light-emitting stack 2311 except for the first anode ohmic contact layer 2311d, thereby reducing the risk of short circuit between the first metal reflective part 233 and the first light-emitting stack 2311.

[0125] In some examples, after the formation of the first light-emitting unit (i.e., after step S1), the method for fabricating the display panel further includes: Connect the first sub-reflector to the anode contact of the substrate.

[0126] Understandably, the first sub-reflective portion 2331 is connected to the first anode layer 2311a, and the first sub-reflective portion 2331 is connected to the anode contact 211 of the substrate 210, so that the first anode layer 2311a can be connected to the anode contact 211 of the substrate 210.

[0127] The first metal reflective portion 233 not only conducts electricity but also reflects light. The first sub-reflective portion 2331 is connected to the anode contact 211 of the substrate 210, so that the first sub-reflective portion 2331 can be located between the first light-emitting layer 2311c and the substrate 210. This allows the light emitted by the first light-emitting layer 2311c to be reflected to the side of the first light-emitting layer 2311c away from the substrate 210, which helps to increase the luminous intensity of the first light-emitting unit 231 in the normal direction.

[0128] The normal direction of the first light-emitting unit 231 is the same as or approximately the same as the thickness direction Z of the substrate 210. The light emission path of the first light-emitting unit 231 in the normal direction is the main light emission path of the first light-emitting unit 231. Increasing the luminous intensity of the first light-emitting unit 231 in the normal direction is beneficial to improving the brightness of the display panel 200.

[0129] Furthermore, the second sub-reflective portion 2332 is located on the side of the second insulating portion 2352 away from the first light-emitting stack 2311, so that the second sub-reflective portion 2332 can surround the first light-emitting stack 2311 to reflect the light emitted by the first light-emitting layer 2311c to the side of the first light-emitting layer 2311c away from the substrate 210, which is beneficial to increase the light-emitting intensity of the first light-emitting unit 231 in the normal direction, thereby improving the brightness of the display panel 200.

[0130] The connection method between the first sub-reflector 2331 and the substrate 210 will be illustrated below with an example. For example, as shown... Figure 8 As shown, after the first metal reflective portion 233 is formed, a third transparent dielectric layer 203 can be formed. The third transparent dielectric layer 203 is stacked on the first substrate 401 near the first light-emitting unit 231, and the first light-emitting unit 231 is embedded in the third transparent dielectric layer 203.

[0131] The material of the third transparent dielectric layer 203 may include oxides, such as silicon oxide. Alternatively, the material of the third transparent dielectric layer 203 may also include nitrides, such as silicon nitride. The third transparent dielectric layer 203 may also include other materials besides oxides and nitrides, and the embodiments of this application do not further limit the material of the third transparent dielectric layer 203.

[0132] The third transparent dielectric layer 203 can be formed using CVD or PVD processes, or other processes. The embodiments of this application do not further limit the process for forming the third transparent dielectric layer 203.

[0133] After the third transparent dielectric layer 203, a third through-hole (not shown in the figure) can be formed in the third transparent dielectric layer 203 to expose the first sub-reflective portion 2331. A metal connector 206 can then be formed within the third through-hole, allowing the metal connector 206 to connect to the first sub-reflective portion 2331. Understandably, the surface of the metal connector 206 away from the first substrate 401 is flush with or approximately flush with the surface of the third transparent dielectric layer 203 away from the first substrate 401.

[0134] The third via can be formed on the third transparent dielectric layer 203 using photolithography or ion beam etching, or other processes can be used. The embodiments of this application do not further limit this.

[0135] The material of the metal connector 206 may include gold, silver or copper, or the metal connector 206 may also include other metal materials. The embodiments of this application do not further limit the material of the metal connector 206.

[0136] The metal connector 206 can be formed using CVD or PVD processes, or other processes. The embodiments of this application do not further limit the forming process of the metal connector 206.

[0137] For example, such as Figure 9 As shown, the metal connector 206 and the anode contact 211 of the substrate 210 can be connected, so that the first anode layer 2311a of the first light-emitting stack 2311 can be connected to the anode contact 211 through the first sub-reflective part 2331 and the metal connector 206.

[0138] The metal connector 206 and the anode contact 211 can be connected by a hybrid bonding method, or the metal connector 206 and the anode contact 211 can be connected by other methods. The embodiments of this application do not further limit the connection method of the metal connector 206 and the anode contact 211.

[0139] Understandably, after the metal connector 206 and the anode contact 211 of the substrate 210 are connected, the first anode layer 2311a is closer to the substrate 210 relative to the first cathode layer 2311b.

[0140] like Figure 10As shown, after connecting the metal connector 206 and the anode contact 211, the first substrate 401 can be peeled off so that the surface of the first light-emitting stack 2311 away from the first substrate 401 can be exposed, that is, the first cathode ohmic contact layer 2311e can be exposed.

[0141] In some examples, after forming the first light-emitting unit 231 and connecting the first light-emitting unit 231 and the substrate 210, the method for manufacturing the display panel 200 further includes: In step S2, a first sub-conductive element is formed on the side of the first cathode layer away from the first anode layer. The first sub-conductive element extends along the stacking direction and is connected to the first cathode layer. The first sub-conductive element avoids the light emission path of the first light-emitting unit in the normal direction.

[0142] Understandably, after the first substrate 401 is peeled off relative to the first light-emitting stack 2311, the first cathode ohmic contact layer 2311e can be exposed. For example, a first sub-conductor 241 can be formed on the side of the first cathode ohmic contact layer 2311e away from the first cathode layer 2311b, and the first sub-conductor 241 is connected to the first cathode ohmic contact layer 2311e and the first cathode layer 2311b.

[0143] The material of the first sub-conductive element 241 may include gold, silver or copper, or the first sub-conductive element 241 may also include other metallic materials. The embodiments of this application do not further limit the material of the first sub-conductive element 241.

[0144] For example, a first initial conductive layer can be formed, and then the first initial conductive layer can be patterned to form a plurality of first sub-conductive elements 241 spaced apart. Understandably, one first sub-conductive element 241 is connected to a first cathode layer 2311b of a first light-emitting stack 2311. This allows the first cathode layer 2311b to be connected to other components via the first sub-conductive elements 241.

[0145] The first initial conductive layer can be formed using CVD or PVD processes, or other processes can be used to form the first initial conductive layer. The embodiments of this application do not further limit this.

[0146] The first initial conductive layer can be patterned using photolithography or ion beam etching processes, or other processes can be used to pattern the first initial conductive layer. The embodiments of this application do not further limit this.

[0147] The orthographic projection of the first sub-conductive element 241 on the substrate 210 can surround the orthographic projection of the first light-emitting stack 2311 on the substrate 210, so that the first sub-conductive element 241 can avoid the light emission path of the first light-emitting unit 231 in the normal direction.

[0148] The first sub-conductive element 241 extends along the stacking direction. Understandably, the stacking direction is the stacking direction of multiple film layers in the first light-emitting stack 2311, and the stacking direction is the same as the thickness direction Z of the substrate 210.

[0149] In some examples, the method for fabricating the display panel before forming the first sub-conductive element (i.e., before step S2) further includes: A first transparent conductive layer is formed on the side of the first light-emitting stack away from the substrate. The first transparent conductive layer is connected to the first cathode layer. The orthogonal projection of the first transparent conductive layer on the substrate covers the orthogonal projection of the first light-emitting stack on the substrate.

[0150] The material of the first transparent conductive layer 234 may include indium tin oxide (ITO) or indium zinc oxide (IZO), or the first transparent conductive layer 234 may also include other transparent conductive materials. The embodiments of this application do not further limit the material of the first transparent conductive layer 234.

[0151] For example, a first initial transparent conductive layer can be formed on the side of the first light-emitting stack 2311 away from the substrate 210, and the first initial transparent conductive layer and the third transparent dielectric layer 203 can be stacked. The first initial transparent conductive layer can then be patterned, such as... Figure 11 As shown, the first transparent conductive layer 234 can be disconnected for portions corresponding to different first light-emitting units 231, thereby avoiding short circuits between two adjacent first light-emitting units 231.

[0152] The first initial transparent conductive layer can be formed using CVD or PVD processes, or other processes. The embodiments of this application do not further limit this.

[0153] The first initial transparent conductive layer can be patterned using photolithography or ion beam etching processes, or other processes can be used to pattern the first initial transparent conductive layer. The embodiments of this application do not further limit this.

[0154] like Figure 11As shown, the first transparent conductive layer 234 can be stacked on the side of the first cathode ohmic contact layer 2311e away from the first cathode layer 2311b and connected to the first cathode ohmic contact layer 2311e, so that the first transparent conductive layer 234 can be connected to the first cathode layer 2311b through the first cathode ohmic contact layer 2311e, thereby reducing the resistance between the first transparent conductive layer 234 and the first cathode layer 2311b.

[0155] The first transparent conductive layer 234 is constructed as a transparent structure, which can reduce the obstruction of light emitted by the first light-emitting unit 231 by the first transparent conductive layer 234.

[0156] like Figure 11 As shown, the orthographic projection of the first transparent conductive layer 234 on the substrate 210 covers the orthographic projection of the first light-emitting stack 2311 on the substrate 210, so that the edge region of the first transparent conductive layer 234 can protrude from the first light-emitting stack 2311.

[0157] In some examples, forming the first sub-conductor (i.e., step S2) includes: A first sub-conductive element is formed on the side of the first transparent conductive layer away from the first light-emitting stack.

[0158] For example, a first sub-conductive element 241 may be formed on the side of the first transparent conductive layer 234 that protrudes from the edge region of the first light-emitting stack 2311 away from the first light-emitting stack 2311, so that the first sub-conductive element 241 can avoid the light emission path of the first light-emitting unit 231 in the normal direction.

[0159] By adopting the above method, the first sub-conductive component 241 can be disposed in the edge region of the first transparent conductive layer 234 protruding from the first light-emitting stack 2311, so as to avoid the light emission path of the first light-emitting unit 231 in the emitting direction.

[0160] In some examples, after the first sub-conductive element is formed on the side of the first cathode layer away from the first anode layer (i.e., after step S2), the method for fabricating the display panel further includes: A first transparent dielectric layer is formed, and a first sub-conductive element is embedded in the first transparent dielectric layer. The end face of the first sub-conductive element away from the first light-emitting unit is flush with the surface of the first transparent dielectric layer away from the first light-emitting unit.

[0161] Understandably, such as Figure 11 As shown, the first transparent dielectric layer 201 is stacked on the side of the first transparent conductive layer 234 away from the first light-emitting unit 231.

[0162] The material of the first transparent dielectric layer 201 may include oxides, such as silicon oxide. Alternatively, the material of the first transparent dielectric layer 201 may also include nitrides, such as silicon nitride. The first transparent dielectric layer 201 may also include other materials besides oxides and nitrides, and the embodiments of this application do not further limit the material of the first transparent dielectric layer 201.

[0163] The first transparent dielectric layer 201 can be formed using CVD or PVD processes, or other processes can be used to form the first transparent dielectric layer 201. The embodiments of this application do not further limit this.

[0164] After the first transparent dielectric layer 201 is formed, chemical mechanical planarization (CMP) can be used to polish the side of the first sub-conductive element 241 and the first transparent dielectric layer 201 away from the first light-emitting unit 231, so that the end face of the first sub-conductive element 241 away from the first light-emitting unit 231 and the surface of the first transparent dielectric layer 201 away from the first light-emitting unit 231 can be flush or nearly flush.

[0165] For example, the end face of the first sub-conductive element 241 away from the first light-emitting unit 231 and the surface of the first transparent dielectric layer 201 away from the first light-emitting unit 231 can form a first surface, and the surface roughness of the first surface can be less than or equal to 1 nanometer (unit: nm).

[0166] In other examples, a first transparent dielectric layer 201 may be formed after the first transparent conductive layer 234 is formed, followed by the formation of a first receiving hole in the first transparent dielectric layer 201, exposing the first transparent conductive layer 234. A first sub-conductive element 241 may then be formed within the first receiving hole, enabling the first sub-conductive element 241 to connect with the first transparent conductive layer 234 and, through the first transparent conductive layer 234, to the first cathode layer 2311b.

[0167] Refer again Figure 3 The manufacturing method of the display panel also includes: Step S3: Form a second light-emitting unit. The second light-emitting unit includes a second light-emitting stack, which includes a second anode layer, a second cathode layer, and a second light-emitting layer. The second anode layer and the second cathode layer are stacked on both sides of the second light-emitting layer. The second anode layer is used to provide holes for the second light-emitting layer, and the second cathode layer is used to provide electrons for the second light-emitting layer. Electrons and holes recombine in the second light-emitting layer to make the second light-emitting layer emit light.

[0168] For example, the second light-emitting unit 232 can be formed before the first light-emitting unit 231 is formed, or the second light-emitting unit 232 can be formed after the first light-emitting unit 231 is formed, or the first light-emitting unit 231 and the second light-emitting unit 232 can be formed simultaneously.

[0169] Understandably, in the embodiments of this application, "simultaneously" refers to the same time period or the same process step, not limited to the same moment.

[0170] For example, such as Figure 12 As shown, the second light-emitting layer 2321c can be a multiple quantum well (MQW) structure. When the light-emitting pixel 220 is a blue or green light-emitting pixel, the material of the second light-emitting layer 2321c can include indium gallium nitride (InGaN). When the light-emitting pixel 220 is a red light-emitting pixel, the material of the second light-emitting layer 2321c can include aluminum gallium indium phosphide (AlGaInP). Alternatively, the second light-emitting layer 2321c can also include other materials; the embodiments of this application do not further limit the material of the second light-emitting layer 2321c.

[0171] The second anode layer 2321a can be a P-type semiconductor layer, enabling it to provide holes for the second light-emitting layer 2321c. When the light-emitting pixel 220 is a blue or green light-emitting pixel, the material of the second anode layer 2321a can include P-type gallium nitride. When the light-emitting pixel 220 is a red light-emitting pixel, the material of the second anode layer 2321a can include P-type aluminum gallium indium phosphide. Alternatively, the second anode layer 2321a can also include other materials; the embodiments of this application do not further limit the material of the second anode layer 2321a.

[0172] The second cathode layer 2321b can be an N-type semiconductor layer, enabling it to provide electrons to the second light-emitting layer 2321c. When the light-emitting pixel 220 is a blue or green light-emitting pixel, the material of the second cathode layer 2321b can include N-type gallium nitride. When the light-emitting pixel 220 is a red light-emitting pixel, the material of the second cathode layer 2321b can include N-type aluminum gallium indium phosphide. Alternatively, the second cathode layer 2321b can also include other materials; the embodiments of this application do not further limit the material of the second cathode layer 2321b.

[0173] Continue to refer to Figure 12The second light-emitting stack 2321 may further include a second ohmic contact layer, which includes a second anode ohmic contact layer 2321d and a second cathode ohmic contact layer 2321e. The second anode ohmic contact layer 2321d is stacked on the side of the second anode layer 2321a away from the second cathode layer 2321b, and the second cathode ohmic contact layer 2321e is stacked on the side of the second cathode layer 2321b away from the second anode layer 2321a.

[0174] Understandably, the second ohmic contact layer (including the second anode ohmic contact layer 2321d and the second cathode ohmic contact layer 2321e) has good conductivity and can reduce the resistance between the second anode layer 2321a and the second cathode layer 2321b and other film layers.

[0175] Alternatively, the second light-emitting stack 2321 may not include the second ohmic contact layer to simplify the second light-emitting stack 2321. The embodiments of this application use the example of the second light-emitting stack 2321 including the second ohmic contact layer for further illustration.

[0176] In some examples, such as Figure 13 As shown, forming the second light-emitting unit (i.e., step S3) includes: In step S31, a second light-emitting stack is formed on one side of the second substrate, with the second anode layer being away from the second substrate relative to the second cathode layer.

[0177] For example, such as Figure 14 As shown, a second initial stack 23211 can be formed on one side of the second substrate 402. The second initial stack 23211 includes a second initial cathode ohmic contact layer 2321ee, a second initial cathode layer 2321bb, a second initial light-emitting layer 2321cc, a second initial anode layer 2321aa, and a second initial anode ohmic contact layer 2321dd, which are stacked together. Along the direction from the second substrate 402 to the second initial stack 23211, the second initial cathode ohmic contact layer 2321ee, the second initial cathode layer 2321bb, the second initial light-emitting layer 2321cc, the second initial anode layer 2321aa, and the second initial anode ohmic contact layer 2321dd are sequentially moved away from the second substrate 402.

[0178] The second initial stack 23211 can be formed on one side of the second substrate 402 using CVD or PVD processes, or other processes can be used to form the second initial stack 23211 on one side of the second substrate 402. The embodiments of this application do not further limit the process for forming the second initial stack 23211.

[0179] After forming the second initial stack 23211, the second initial stack 23211 can be patterned to form a plurality of second light-emitting stacks 2321 spaced apart (see [reference]). Figure 12 For example, the second initial stack 23211 can be patterned using photolithography or ion beam etching processes, or other processes can be used to pattern the second initial stack 23211, which is not further limited by the embodiments of this application.

[0180] Understandably, the second initial anode layer 2321aa is farther away from the second substrate 402 relative to the second initial cathode layer 2321bb, such that the second anode layer 2321a is able to be farther away from the second substrate 402 relative to the second cathode layer 2321b.

[0181] Step S32: Form a second transparent conductive layer. The second transparent conductive layer includes a first conductive portion. The orthogonal projection of the first conductive portion on the second substrate surrounds the orthogonal projection of the second light-emitting stack on the second substrate, and the first conductive portion and the second anode layer are connected.

[0182] The material of the second transparent conductive layer 236 may include indium tin oxide (ITO) or indium zinc oxide (IZO), or the second transparent conductive layer 236 may also include other transparent conductive materials. The embodiments of this application do not further limit the material of the second transparent conductive layer 236.

[0183] For example, a second initial transparent conductive layer can be formed first, and then the second initial transparent conductive layer can be patterned so that the portions of the second transparent conductive layer 236 corresponding to different second light-emitting units 232 can be disconnected, thereby avoiding short circuits between two adjacent second light-emitting units 232.

[0184] The second initial transparent conductive layer can be formed using CVD or PVD processes, or other processes can be used to form the second initial transparent conductive layer. The embodiments of this application do not further limit this.

[0185] The second initial transparent conductive layer can be patterned using photolithography or ion beam etching processes, or other processes can be used to pattern the second initial transparent conductive layer. The embodiments of this application do not further limit this.

[0186] The second transparent conductive layer 236 is constructed as a transparent structure, which can reduce the obstruction of light emitted by the second light-emitting unit 232 by the second transparent conductive layer 236.

[0187] The first conductive part 2361 and the second anode layer 2321a are connected, so that other components (such as the second sub-conductive part 242) and the first conductive part 2361 can be connected through the first conductive part 2361 and the second anode layer 2321a.

[0188] Understandably, the orthographic projection of the first conductive part 2361 on the second substrate 402 surrounds the orthographic projection of the second light-emitting stack 2321 on the second substrate 402, so that the orthographic projection of other components (such as the second sub-conductive part 242) connected to the first conductive part 2361 on the second substrate 402 can surround the orthographic projection of the second light-emitting stack 2321 on the second substrate 402, thereby avoiding the light emission path of the second light-emitting unit 232 in the normal direction.

[0189] In some examples, the method for fabricating the display panel before forming the second transparent conductive layer (i.e., before step S22) further includes: A second transparent insulating layer is formed, which includes a fourth insulating portion, a fifth insulating portion and a sixth insulating portion. The fourth insulating portion is stacked on the side of the second substrate near the second light-emitting stack and surrounds the second light-emitting stack. The fifth insulating portion is disposed on the side of the second light-emitting stack. The sixth insulating portion is stacked on the side of the second light-emitting stack away from the second substrate. The fifth insulating portion connects the fourth insulating portion and the sixth insulating portion. A second through hole is formed on the sixth insulating portion, and the second through hole exposes the second light-emitting stack.

[0190] like Figure 15 As shown, the second transparent insulating layer 237 can cover the surface of the second light-emitting stack 2321 away from the second substrate 402 and the side surface of the second light-emitting stack 2321. The second transparent insulating layer 237 can play a role in electrical isolation, reducing the risk of short circuit between the second light-emitting stack 2321 and other film layers.

[0191] The material of the second transparent insulating layer 237 may include oxides, such as silicon oxide. Alternatively, the material of the second transparent insulating layer 237 may also include nitrides, such as silicon nitride. It is understood that the second transparent insulating layer 237 may also include other materials besides oxides and nitrides, and the embodiments of this application do not further limit the material of the second transparent insulating layer 237.

[0192] For example, a second initial transparent insulating layer can be formed first to cover the second light-emitting stack 2321, and then a second through hole P2 can be opened on the second initial transparent insulating layer to expose the second light-emitting stack 2321, so as to form a second transparent insulating layer 237.

[0193] The second initial transparent insulating layer can be formed using CVD or PVD processes, or other processes. The embodiments of this application do not further limit the process for forming the second transparent insulating layer 237.

[0194] The second via P2 can be formed on the second initial transparent insulating layer using photolithography or ion beam etching processes, and the embodiments of this application do not further limit this.

[0195] Continue to refer to Figure 15 For example, the second transparent insulating layer 237 may include a fourth insulating portion 2371, a fifth insulating portion 2372, and a sixth insulating portion 2373.

[0196] A fourth insulating portion 2371 is stacked on the side of the second substrate 402 near the second light-emitting stack 2321 and surrounds the second light-emitting stack 2321. A fifth insulating portion 2372 is located on the side of the second light-emitting stack 2321. A sixth insulating portion 2373 is stacked on the side of the second light-emitting stack 2321 away from the second substrate 402, that is, the sixth insulating portion 2373 is stacked on the side of the second cathode ohmic contact layer 2321e away from the second substrate 402.

[0197] The second through-hole P2 can be formed on the sixth insulating portion 2373 to expose the second anode ohmic contact layer 2321d of the second light-emitting stack 2321. In this way, other components (such as the second transparent conductive layer 236) can be connected through the second anode ohmic contact layer 2321d and the second anode layer 2321a.

[0198] Understandably, after the second transparent insulating layer 237 is formed, a second transparent conductive layer 236 can be formed on the side of the second transparent insulating layer 237 away from the second light-emitting stack 2321.

[0199] like Figure 16 , Figure 17 and Figure 18 As shown in the example, the second transparent conductive layer 236 may also include a second conductive portion 2362 and a third conductive portion 2363.

[0200] The third conductive part 2363 is located on the side of the sixth insulating part 2373 away from the second light-emitting stack 2321, and the second conductive part 2362 connects the first conductive part 2361 and the third conductive part 2363.

[0201] A portion of the third conductive part 2363 is located within the second through hole P2 and is connected to the second anode ohmic contact layer 2321d, so that the third conductive part 2363 can be connected through the second anode ohmic contact layer 2321d and the second anode layer 2321a, thereby reducing the resistance between the third conductive part 2363 and the second anode layer 2321a.

[0202] Understandably, the third conductive part 2363 is connected to the second anode layer 2321a, and the second conductive part 2362 is connected to the first conductive part 2361 and the third conductive part 2363, so that the first conductive part 2361 can be connected to the second anode layer 2321a. In this way, other components (such as the second sub-conductive member 242) can be connected to the first conductive part 2361 and thus connected to the second anode layer 2321a.

[0203] After the formation of the second light-emitting unit (i.e., after step S3), the method for fabricating the display panel further includes: Step S4: A second sub-conductive element is formed. The second sub-conductive element extends along the stacking direction and protrudes from the second light-emitting unit. The second sub-conductive element is connected to the second anode layer and avoids the light emission path of the second light-emitting unit in the normal direction.

[0204] Understandably, the second sub-conductor 242 is connected to the second anode layer 2321a, and the first sub-conductor 241 is connected to the first cathode layer 2311b. In this way, by connecting the second sub-conductor 242 and the first sub-conductor 241, the first cathode layer 2311b can be connected to the second anode layer 2321a, which means that the first light-emitting unit 231 can be connected in series with the second light-emitting unit 232.

[0205] The end face of the second sub-conductive element 242 away from the second substrate 402 can protrude from the side of the second light-emitting unit 232 away from the second substrate 402. That is, the side of the second sub-conductive element 242 away from the second substrate 402 can protrude from the surface of the third conductive part 2363 away from the second light-emitting stack 2321, so that the end face of the second sub-conductive element 242 away from the second substrate 402 can be connected to the first sub-conductive element 241, reducing the impact of the second light-emitting unit 232 on the connection between the second sub-conductive element 242 and the first sub-conductive element 241.

[0206] In some examples, forming the second sub-conductor (i.e., step S4) includes: A second sub-conductive element is formed on the side of the first conductive portion away from the second substrate.

[0207] For example, such as Figure 19 , Figure 20 and Figure 21As shown, a second sub-conductive element 242 is formed on the side of the first conductive portion 2361 away from the second substrate 402, such that the second sub-conductive element 242 can be connected through the first conductive portion 2361 and the second anode layer 2321a. Furthermore, the orthographic projection of the first conductive portion 2361 onto the second substrate 402 surrounds the orthographic projection of the second light-emitting stack 2321 onto the second substrate 402, allowing the first conductive portion 2361 to avoid the light emission path of the second light-emitting unit 232 in the normal direction. The second sub-conductive element 242 is located on the side of the second conductive portion 2362 away from the second substrate 402, allowing the second sub-conductive element 242 to avoid the light emission path of the second light-emitting unit 232 in the normal direction.

[0208] The material of the second sub-conductive element 242 may include gold, silver or copper, or the second sub-conductive element 242 may also include other metallic materials. The embodiments of this application do not further limit the material of the second sub-conductive element 242.

[0209] For example, a second initial conductive layer can be formed, and then the second initial conductive layer can be patterned to form a plurality of second sub-conductive elements 242 spaced apart. Understandably, one second sub-conductive element 242 is connected to a second anode layer 2321a of a second light-emitting stack 2321. This allows the second anode layer 2321a to be connected to other components via the second sub-conductive elements 242.

[0210] The second initial conductive layer can be formed using CVD or PVD processes, or other processes can be used. The embodiments of this application do not further limit this.

[0211] The second initial conductive layer can be patterned using photolithography or ion beam etching processes, or other processes can be used to pattern the second initial conductive layer. The embodiments of this application do not further limit this.

[0212] Continue to refer to Figure 19 , Figure 20 and Figure 21 After the second sub-conductive element is formed (i.e., step S4), the method for fabricating the display panel further includes: A second transparent dielectric layer is formed, and a second sub-conductive element and a second light-emitting unit are embedded in the second transparent dielectric layer. The end face of the second sub-conductive element protruding from one side of the second anode layer is flush with the surface of the second transparent dielectric layer on the side away from the second anode layer.

[0213] like Figure 19 , Figure 20 and Figure 21The second transparent dielectric layer 202 is stacked on the side of the second substrate 402 near the second light-emitting unit 232, and the second light-emitting unit 232 and the second sub-conductive element 242 are embedded in the second transparent dielectric layer 202.

[0214] The material of the second transparent dielectric layer 202 may include oxides, such as silicon oxide. Alternatively, the material of the second transparent dielectric layer 202 may also include nitrides, such as silicon nitride. The second transparent dielectric layer 202 may also include other materials besides oxides and nitrides, and the embodiments of this application do not further limit the material of the second transparent dielectric layer 202.

[0215] The second transparent dielectric layer 202 can be formed using CVD or PVD processes, or other processes can be used to form the second transparent dielectric layer 202. The embodiments of this application do not further limit this.

[0216] After the second transparent dielectric layer 202 is formed, chemical mechanical planarization (CMP) can be used to polish the side of the second sub-conductive element 242 and the second transparent dielectric layer 202 away from the second substrate 402, so that the end face of the second sub-conductive element 242 away from the second substrate 402 and the surface of the second transparent dielectric layer 202 away from the second substrate 402 can be flush or nearly flush.

[0217] For example, the end face of the second sub-conductive element 242 on the side away from the second substrate 402 and the surface of the second transparent dielectric layer 202 on the side away from the second substrate 402 can form a second surface, and the surface roughness of the second surface can be less than or equal to 1 nanometer (unit: nm).

[0218] In other examples, a second transparent dielectric layer 202 may be formed after the second transparent conductive layer 236 is formed, followed by the formation of a second receiving hole in the second transparent dielectric layer 202, which exposes the first conductive portion 2361 of the second transparent conductive layer 236. A second sub-conductive element 242 may then be formed within the second receiving hole, allowing the second sub-conductive element 242 to connect with the first conductive portion 2361 and to the second anode layer 2321a via the first conductive portion 2361.

[0219] In some examples, such as Figure 16 and Figure 19 As shown, a second transparent conductive layer 236 can be formed after the first transparent insulating layer 235 is formed, so that the first conductive portion 2361 can be stacked on one side of the fourth insulating portion 2371 and connected to the fourth insulating portion 2371.

[0220] In this way, the second sub-conductive member 242 connected to the first conductive part 2361 can surround the second light-emitting layer 2321c, thereby reflecting the light emitted by the second light-emitting layer 2321c, reducing the light crosstalk between two adjacent second light-emitting units 232, and improving the light-emitting brightness of the second light-emitting unit 232 in the emitting direction.

[0221] In other examples, the method for fabricating the display panel, after the formation of the second transparent insulating layer and before the formation of the second transparent conductive layer, further includes: A first sublayer forming a second transparent dielectric layer is provided, and a first conductive portion is stacked on the side of the first sublayer away from the second substrate.

[0222] like Figure 17 , Figure 18 , Figure 20 and Figure 21 As shown, a first sub-layer 2021 of the second transparent dielectric layer 202 is formed after the formation of the second transparent insulating layer 237 and before the formation of the second transparent conductive layer 236, so that the first sub-layer 2021 can be stacked between the first conductive portion 2361 and the fourth insulating portion 2371, that is, the first sub-layer 2021 can raise the first conductive portion 2361.

[0223] This reduces the length of the second sub-conductive member 242 connected to the first conductive part 2361, thereby reducing the resistance of the second sub-conductive member 242 and simplifying its fabrication, which in turn improves the production yield of the display panel 200.

[0224] For example, such as Figure 20 As shown in the example, after the first conductive part 2361 is raised by the first sub-layer 2021, the end face of the second sub-conductive member 242 near the second substrate 402 along the thickness direction Z of the substrate 210 can be flush with or approximately flush with the second light-emitting layer 2321c.

[0225] In this way, the second sub-conductive element 242 can reflect a portion of the light emitted by the second light-emitting unit 232, thereby suppressing light crosstalk between two adjacent light-emitting pixels 220 and ensuring the light mixing effect between two adjacent second light-emitting units 232.

[0226] Or, such as Figure 21 As shown, after the first sublayer 2021 raises the first conductive part 2361, along the thickness direction Z of the substrate 210, the end face of the second subconducting member 242 near the second substrate 402 can be flush with or approximately flush with the side surface of the second light-emitting stack 2321 away from the second substrate 402.

[0227] This reduces the impact of the second sub-conductive element 242 on the light emitted by the second light-emitting unit 232, thus improving the light mixing effect between two adjacent second light-emitting units 232. Furthermore, it allows for a smaller length of the second sub-conductive element 242, reducing its resistance and simplifying its fabrication.

[0228] Understandably, after the second sub-conductive element 242 is formed, a second sub-layer 2022 of the second transparent dielectric layer 202 can be formed, and the second sub-layer 2022 is stacked on the side of the first sub-layer 2021 away from the second substrate 402.

[0229] In some examples, the fabrication method of the display panel further includes, prior to the formation of the first sublayer of the second transparent dielectric layer: A second metal reflective portion is formed, and at least a portion of the second metal reflective portion is located on the side of the sixth insulating portion away from the second light-emitting stack. The second metal reflector is embedded within the first sublayer.

[0230] Understandably, such as Figure 20 and Figure 21 As shown, after the formation of the second transparent insulating layer 237 and before the formation of the first sub-layer 2021, a second metal reflective portion 238 can be formed. The second metal reflective portion 238 is located on the side of the fifth insulating portion 2372 away from the second light-emitting stack 2321, so that the second metal reflective portion 238 can reflect the light emitted by the second light-emitting layer 2321c.

[0231] The second metal reflective portion 238 is embedded within the first sub-layer 2021 to reduce the mutual influence between the second metal reflective portion 238 and the second transparent conductive layer 236.

[0232] Understandably, the second metal reflective portion 238 and the second sub-conductive member 242 are arranged along the thickness direction Z so that the second metal reflective portion 238 and the second sub-conductive member 242 can jointly reflect the light emitted by the second light-emitting layer 2321c, reduce the light crosstalk between two adjacent second light-emitting units 232, and help improve the light emission brightness of the second light-emitting unit 232 in the emission direction.

[0233] For example, the material of the second metal reflective portion 238 may include gold, silver or copper, or the second metal reflective portion 238 may also include other metal materials. The embodiments of this application do not further limit the material of the second metal reflective portion 238.

[0234] The second metal reflective portion 238 can be formed using CVD or PVD processes, or other processes. The embodiments of this application do not further limit the process for forming the second metal reflective portion 238.

[0235] In some examples, after forming the first and second light-emitting units, the method for fabricating the display panel further includes: Step S5: Hybrid bonding (HB) is performed on the end face of the first sub-conductive element away from the first cathode layer and the end face of the second sub-conductive element protruding from the second light-emitting unit.

[0236] For example, the first sub-conductive element 241 and the second sub-conductive element 242 can be made of the same material, such as copper.

[0237] like Figure 22 , Figure 23 and Figure 24 As shown, the end face of the first sub-conductor 241 away from the first cathode layer 2311b and the end face of the second sub-conductor 242 protruding from the second light-emitting unit 232 are mixed and bonded, so that the first light-emitting unit 231 and the second light-emitting unit 232 can be stacked along the thickness direction Z of the substrate 210, and the first cathode layer 2311b and the second anode layer 2321a can be connected in series through the first sub-conductor 241 and the second sub-conductor 242, so that the current can drive the first light-emitting unit 231 and the second light-emitting unit 232 to emit light together.

[0238] The stacked first light-emitting unit 231 and second light-emitting unit 232 can form a light-emitting pixel 220. Understandably, with a constant current value, simultaneous emission of light from the first light-emitting unit 231 and the second light-emitting unit 232 can increase the brightness of the light-emitting pixel 220; with a constant brightness of the light-emitting pixel 220, a smaller current can be set for the first light-emitting unit 231 and the second light-emitting unit 232. For example, the driving current can be reduced to half of its original value.

[0239] By using the above setting method, a smaller current value can be set so that the light-emitting pixel 220 can reach the set light-emitting brightness. While ensuring the light-emitting brightness of the light-emitting pixel 220, the current driving the light-emitting unit can be reduced, thereby reducing heat loss and reducing the power consumption of the display panel 200. In addition, reducing heat loss can also reduce the heat generated by the display panel 200, reduce the impact of heat on other devices (such as the driver chip), and help extend the service life of the display panel 200.

[0240] Furthermore, by setting a smaller current value to drive the stacked light-emitting units while keeping the parasitic resistance of the substrate 210 constant, the voltage drop of the substrate 210 can be reduced, thereby improving the reliability of the substrate 210 in driving the light-emitting units to emit light.

[0241] In other words, the embodiments of this application, through a vertically stacked and cascaded pixel structure, enable the light-emitting pixel 220 to achieve low-power, high-brightness light emission without increasing the driving difficulty of the light-emitting pixel 220 or increasing the space occupied by the light-emitting pixel 220 on the substrate 210. For example, the light-emitting pixel 220 can be referred to as a high-voltage light-emitting pixel.

[0242] Understandably, the end face of the first sub-conductor 241 away from the first cathode layer 2311b and the end face of the second sub-conductor 242 protruding from the second light-emitting unit 232 are both CMP treated, so that the end face of the first sub-conductor 241 away from the first cathode layer 2311b and the end face of the second sub-conductor 242 protruding from the second light-emitting unit 232 can be relatively flat, thereby improving the reliability of the hybrid bonding of the first sub-conductor 241 and the second sub-conductor 242.

[0243] By using a hybrid bonding method to connect the first sub-conductive component 241 and the second sub-conductive component 242, there is no need to set a bonding layer between the first sub-conductive component 241 and the second sub-conductive component 242. The first sub-conductive component 241 and the second sub-conductive component 242 can be exposed on the first transparent dielectric layer 201 and the second transparent dielectric layer 202, which helps to reduce the thickness of the display panel 200.

[0244] In other words, in the embodiments of this application, the first sub-conductive element 241 and the second sub-conductive element 242 can not only conduct electricity, but also connect the first light-emitting unit 231 and the second light-emitting unit 232.

[0245] Understandably, after the first sub-conductive element 241 and the second sub-conductive element 242 are mixed and bonded, the first sub-conductive element 241 and the second sub-conductive element 242 can be connected into a whole. In this way, the connection reliability of the first sub-conductive element 241 and the second sub-conductive element 242 can be improved, thereby improving the connection reliability of the first light-emitting unit 231 and the second light-emitting unit 232.

[0246] For example, after the first sub-conductor 241 and the second sub-conductor 242 are mixed and bonded, a bonding region will be formed between them.

[0247] For example, after the first sub-conductive element 241 and the second sub-conductive element 242 are hybrid bonded, the deviation between the first sub-conductive element 241 and the second sub-conductive element 242 on the reference plane is less than 0.5 micrometers (μm), and the reference plane is parallel to the substrate 210. In this way, a smaller pixel pitch can be set to improve the resolution of the display panel 200.

[0248] In some examples, the method for manufacturing the display panel also includes: The surfaces of the first transparent dielectric layer away from the first light-emitting unit and the second transparent dielectric layer away from the second anode layer are mixed and bonded.

[0249] For example, the materials of the first transparent dielectric layer 201 and the second transparent dielectric layer 202 can be the same, such as silicon dioxide.

[0250] During the mixing and spacing process of the first sub-conductive element 241 and the second sub-conductive element 242, the surface of the first transparent dielectric layer 201 away from the first light-emitting unit 231 and the surface of the second transparent dielectric layer 202 away from the second anode layer 2321a can be mixed and bonded.

[0251] The first transparent dielectric layer 201 and the second transparent dielectric layer 202 are connected by a hybrid bonding method, which eliminates the need for a bonding layer between the first transparent dielectric layer 201 and the second transparent dielectric layer 202, thus reducing the thickness of the display panel 200.

[0252] Understandably, after the first transparent dielectric layer 201 and the second transparent dielectric layer 202 are mixed and bonded, the first transparent dielectric layer 201 and the second transparent dielectric layer 202 can be connected into a whole. In this way, the connection reliability of the first transparent dielectric layer 201 and the second transparent dielectric layer 202 can be improved, thereby improving the connection reliability of the first light-emitting unit 231 and the second light-emitting unit 232.

[0253] For example, such as Figure 25 , Figure 26 and Figure 27 As shown, after the first transparent dielectric layer 201 and the second transparent dielectric layer 202 are mixed and bonded, and the first sub-conductive element 241 and the second sub-conductive element 242 are mixed and bonded, the second substrate 402 can be peeled off, so that the second cathode ohmic contact layer 2321e can be exposed, thereby enabling the second cathode ohmic contact layer 2321e to be connected to the cathode contact of the substrate 210.

[0254] like Figure 28 , Figure 29 and Figure 30As shown, after exposing the second cathode ohmic contact layer 2321e, a third transparent conductive layer 251 can be formed on the side of the second cathode ohmic contact layer 2321e away from the second cathode layer 2321b. The third transparent conductive layer 251 is a single-layer structure and is connected to the second cathode ohmic contact layers 2321e of the multiple second light-emitting stacks 2321, so that the third transparent conductive layer 251 can be connected to the second cathode layer 2321b of the multiple second light-emitting stacks 2321 through the multiple second cathode ohmic contact layers 2321e, thereby reducing the resistance between the second cathode layer 2321b and the third transparent conductive layer 251.

[0255] The material of the third transparent conductive layer 251 may include indium tin oxide (ITO) or indium zinc oxide (IZO), or the third transparent conductive layer 251 may also include other transparent conductive materials. The embodiments of this application do not further limit the material of the third transparent conductive layer 251.

[0256] The third transparent conductive layer 251 can be formed using CVD or PVD processes, or other processes. The embodiments of this application do not further limit this.

[0257] After the third transparent conductive layer 251 is formed, a cathode metal 205 can be formed on the side of the third transparent conductive layer 251 away from the second light-emitting stack 2321. The cathode metal 205 and the third transparent conductive layer 251 are connected, so that the cathode metal 205 can be connected to the second cathode layer 2321b through the third transparent conductive layer 251.

[0258] The cathode metal 205 is used to connect with the cathode contact of the substrate 210. For example, the orthographic projection of the cathode metal 205 on the substrate 210 can surround the orthographic projections of the first light-emitting unit 231 and the second light-emitting unit 232 on the substrate 210, so that the cathode metal 205 can avoid the light emission paths of the first light-emitting unit 231 and the second light-emitting unit 232 in the normal direction.

[0259] The cathode metal 205 may be made of gold, silver or copper, or it may be made of other metal materials. The embodiments of this application do not further limit the material of the cathode metal 205.

[0260] For example, an initial cathode layer can be formed, which is stacked on the side of the third transparent conductive layer 251 away from the second light-emitting unit 232. The initial cathode layer is then patterned to form cathode metal 205.

[0261] The initial cathode layer can be formed using CVD or PVD processes, or other processes. The embodiments of this application do not further limit the process for forming the initial cathode layer.

[0262] The initial cathode layer can be patterned using photolithography or ion beam etching processes, or other processes can be used. The embodiments of this application do not further limit this.

[0263] By adopting the above method, the cathodes of multiple second light-emitting units 232 can be connected to the cathode of substrate 210 by means of metal connection, that is, multiple second light-emitting units 232 can share a common cathode, thereby simplifying the structure of display panel 200.

[0264] After the cathode metal 205 is formed, a fourth transparent dielectric layer 204 can be formed. The fourth transparent dielectric layer 204 is stacked on the side of the third transparent conductive layer 251 away from the second light-emitting unit 232, and the cathode metal 205 is embedded in the fourth transparent dielectric layer 204.

[0265] The material of the fourth transparent dielectric layer 204 may include oxides, such as silicon oxide. Alternatively, the material of the fourth transparent dielectric layer 204 may also include nitrides, such as silicon nitride. It is understood that the fourth transparent dielectric layer 204 may also include other materials besides oxides and nitrides, and the embodiments of this application do not further limit the material of the fourth transparent dielectric layer 204.

[0266] The fourth transparent dielectric layer 204 can be formed using CVD or PVD processes, or other processes. The embodiments of this application do not further limit the process for forming the fourth transparent dielectric layer 204.

[0267] In other examples, a fourth transparent dielectric layer 204 may be formed after the third transparent conductive layer 251 is formed, followed by the formation of a third receiving hole in the fourth transparent dielectric layer 204, exposing the third transparent conductive layer 251. A cathode metal 205 may then be formed within the third receiving hole, enabling the cathode metal 205 to be connected to and through the third transparent conductive layer 251.

[0268] like Figure 31 , Figure 32 and Figure 33 As shown, after the fourth transparent dielectric layer 204 is formed, a microlens 207 can be formed on the side of the fourth transparent dielectric layer 204 away from the second light-emitting unit 232.

[0269] The microlens 207 can be a convex lens, which acts as a light-focusing lens. The microlens 207 is located on the side of the light-emitting pixel 220 away from the substrate 210, which can improve the brightness of the light-emitting pixel 220 in the normal direction.

[0270] For example, the material of the microlens 207 may include glass or other transparent materials. The embodiments of this application do not further limit the material of the microlens 207.

[0271] On the other hand, embodiments of this application provide a display panel 200. For example, the display panel 200 may be a display panel 200 manufactured using the above-described display panel manufacturing method.

[0272] like Figure 31 , Figure 32 and Figure 33 As shown, the display panel 200 includes a substrate 210, a plurality of light-emitting pixels 220, a first sub-conductive element 241, and a second sub-conductive element 242.

[0273] Multiple light-emitting pixels 220 are disposed on one side of substrate 210 along the thickness direction Z of substrate 210. The multiple light-emitting pixels 220 are spaced apart. Each light-emitting pixel 220 includes multiple light-emitting units 230. The multiple light-emitting units 230 are stacked along the thickness direction Z of substrate 210. Two light-emitting units 230 disposed adjacent to each other along the thickness direction Z of substrate 210 include a first light-emitting unit 231 and a second light-emitting unit 232.

[0274] The first light-emitting unit 231 includes a first light-emitting stack 2311, which includes a first anode layer 2311a, a first cathode layer 2311b, and a first light-emitting layer 2311c. The first anode layer 2311a and the first cathode layer 2311b are stacked on both sides of the first light-emitting layer 2311c.

[0275] The second light-emitting unit 232 includes a second light-emitting stack 2321, which includes a second anode layer 2321a, a second cathode layer 2321b, and a second light-emitting layer 2321c. The second anode layer 2321a and the second cathode layer 2321b are stacked on both sides of the second light-emitting layer 2321c.

[0276] The first sub-conductive element 241 extends along the stacking direction and is connected to the first cathode layer 2311b. The first sub-conductive element 241 avoids the light emission path of the first light-emitting unit 231 in the normal direction.

[0277] The second sub-conductive element 242 extends along the stacking direction and protrudes from the second light-emitting unit 232. The second sub-conductive element 242 is connected to the second anode layer 2321a. The second sub-conductive element 242 avoids the light emission path of the second light-emitting unit 232 in the normal direction.

[0278] The end face of the first sub-conductive element 241 away from the first cathode layer 2311b and the end face of the second sub-conductive element 242 protruding from the second light-emitting unit 232 are mixed and bonded.

[0279] For example, the first sub-conductive element 241 and the second sub-conductive element 242 can be made of the same material, such as copper.

[0280] By using the above setting method, a smaller current value can be set so that the light-emitting pixel 220 can reach the set light-emitting brightness. While ensuring the light-emitting brightness of the light-emitting pixel 220, the current driving the light-emitting unit can be reduced, thereby reducing heat loss and reducing the power consumption of the display panel 200. In addition, reducing heat loss can also reduce the heat generated by the display panel 200, reduce the impact of heat on other devices (such as the driver chip), and help extend the service life of the display panel 200.

[0281] Furthermore, by setting a smaller current value to drive the stacked light-emitting units while keeping the parasitic resistance of the substrate 210 constant, the voltage drop of the substrate 210 can be reduced, thereby improving the reliability of the substrate 210 in driving the light-emitting units to emit light.

[0282] In other words, the embodiments of this application, through a vertically stacked and cascaded pixel structure, enable the light-emitting pixel 220 to achieve low-power, high-brightness light emission without increasing the driving difficulty of the light-emitting pixel 220 or increasing the space occupied by the light-emitting pixel 220 on the substrate 210. For example, the light-emitting pixel 220 can be referred to as a high-voltage light-emitting pixel.

[0283] By using a hybrid bonding method to connect the first sub-conductive component 241 and the second sub-conductive component 242, there is no need to set a bonding layer between the first sub-conductive component 241 and the second sub-conductive component 242. The first sub-conductive component 241 and the second sub-conductive component 242 can be exposed on the first transparent dielectric layer 201 and the second transparent dielectric layer 202, which helps to reduce the thickness of the display panel 200.

[0284] For example, after the first sub-conductor 241 and the second sub-conductor 242 are mixed and bonded, a bonding region will be formed between them.

[0285] For example, after the first sub-conductive element 241 and the second sub-conductive element 242 are hybrid bonded, the deviation between the first sub-conductive element 241 and the second sub-conductive element 242 on the reference plane is less than 0.5 micrometers (μm), and the reference plane is parallel to the substrate 210. In this way, a smaller pixel pitch can be set to improve the resolution of the display panel 200.

[0286] In some examples, the display panel also includes a first transparent dielectric layer 201 and a second transparent dielectric layer 202.

[0287] The first transparent dielectric layer 201 is stacked on the side of the first light-emitting unit 231 near the first sub-conductive component 241. The first sub-conductive component 241 is embedded in the first transparent dielectric layer 201. The end face of the first sub-conductive component 241 away from the first light-emitting unit 231 is flush with the surface of the first transparent dielectric layer 201 away from the first light-emitting unit 231.

[0288] A second transparent dielectric layer 202 is stacked on the side of the first transparent dielectric layer 201 away from the substrate 210. A second sub-conductive element 242 is embedded in the second transparent dielectric layer 202. The end face of the second sub-conductive element 242 protruding from the side of the second anode layer 2321a is flush with the surface of the second transparent dielectric layer 202 away from the second anode layer 2321a. The first transparent dielectric layer 201 and the second transparent dielectric layer 202 are co-bonded.

[0289] For example, the materials of the first transparent dielectric layer 201 and the second transparent dielectric layer 202 can be the same, such as silicon dioxide.

[0290] Understandably, after the first transparent dielectric layer 201 and the second transparent dielectric layer 202 are mixed and bonded, the first transparent dielectric layer 201 and the second transparent dielectric layer 202 can be connected into a whole. In this way, the connection reliability of the first transparent dielectric layer 201 and the second transparent dielectric layer 202 can be improved, thereby improving the connection reliability of the first light-emitting unit 231 and the second light-emitting unit 232.

[0291] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of this application, and are not intended to limit them; although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some or as many of the technical features as possible; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method for manufacturing a display panel, characterized in that, include: A first light-emitting unit is formed, the first light-emitting unit includes a first light-emitting stack, the first light-emitting stack includes a first anode layer, a first cathode layer and a first light-emitting layer, the first anode layer and the first cathode layer are stacked on both sides of the first light-emitting layer, the first anode layer is used to provide holes for the first light-emitting layer, the first cathode layer is used to provide electrons for the first light-emitting layer, and electrons and holes recombine in the first light-emitting layer to make the first light-emitting layer emit light. A first sub-conductive element is formed on the side of the first cathode layer away from the first anode layer. The first sub-conductive element extends along the stacking direction and is connected to the first cathode layer. The orthographic projection of the first sub-conductive element on the substrate surrounds the orthographic projection of the first light-emitting stack on the substrate, so that the first sub-conductive element avoids the light emission path of the first light-emitting unit in the normal direction. A second light-emitting unit is formed, the second light-emitting unit includes a second light-emitting stack, the second light-emitting stack includes a second anode layer, a second cathode layer and a second light-emitting layer, the second anode layer and the second cathode layer are stacked on both sides of the second light-emitting layer, the second anode layer is used to provide holes for the second light-emitting layer, the second cathode layer is used to provide electrons for the second light-emitting layer, and electrons and holes recombine in the second light-emitting layer to make the second light-emitting layer emit light; A second sub-conductive element is formed, the second sub-conductive element extends along the stacking direction and protrudes from the second light-emitting unit, the second sub-conductive element is connected to the second anode layer, and the orthographic projection of the second sub-conductive element on the substrate surrounds the orthographic projection of the second light-emitting stack on the substrate, so that the second sub-conductive element avoids the light emission path of the second light-emitting unit in the normal direction; The end face of the first sub-conductive component away from the first cathode layer and the end face of the second sub-conductive component protruding from the second light-emitting unit are mixed and bonded together, and no bonding layer is provided between the first sub-conductive component and the second sub-conductive component.

2. The method for manufacturing a display panel according to claim 1, characterized in that, After forming the first sub-conductive element on the side of the first cathode layer away from the first anode layer, the method for manufacturing the display panel further includes: A first transparent dielectric layer is formed, and the first sub-conductive element is embedded in the first transparent dielectric layer. The end face of the first sub-conductive element away from the first light-emitting unit is flush with the surface of the first transparent dielectric layer away from the first light-emitting unit. After forming the second sub-conductive element, the method for manufacturing the display panel further includes: A second transparent dielectric layer is formed, and the second sub-conductive element and the second light-emitting unit are embedded in the second transparent dielectric layer. The end face of the second sub-conductive element protruding from the side of the second anode layer is flush with the surface of the second transparent dielectric layer away from the second anode layer. The method for manufacturing the display panel further includes: The surface of the first transparent dielectric layer away from the first light-emitting unit and the surface of the second transparent dielectric layer away from the second anode layer are mixed and bonded.

3. The method for manufacturing a display panel according to claim 1, characterized in that, The first light-emitting unit is formed by: The first light-emitting stack is formed on one side of the first substrate, and the first anode layer is located away from the first substrate relative to the first cathode layer; A first transparent insulating layer is formed, the first transparent insulating layer includes a first insulating portion, the first insulating portion is stacked on the side of the first light-emitting stack away from the first substrate, and a first through hole is formed on the first insulating portion, the first through hole exposing the first light-emitting stack; A first metal reflective portion is formed, the first metal reflective portion includes a first sub-reflective portion, the first sub-reflective portion is stacked on the side of the first insulating portion away from the light-emitting stack, and the first sub-reflective portion is connected to the first anode layer through the first through hole; After forming the first light-emitting unit, the method for manufacturing the display panel further includes: Connect the first sub-reflector to the anode contact of the substrate.

4. The method for manufacturing a display panel according to claim 3, characterized in that, The first transparent insulating layer further includes a second insulating portion, which is located on the side of the first light-emitting stack and connected to the first insulating portion; The first metal reflective portion further includes a second sub-reflective portion, which is located on the side of the second insulating portion away from the first light-emitting stack and is connected to the first sub-reflective portion.

5. The method for manufacturing a display panel according to claim 3, characterized in that, Before forming the first sub-conductive element, the method for manufacturing the display panel further includes: A first transparent conductive layer is formed on the side of the first light-emitting stack away from the substrate. The first transparent conductive layer is connected to the first cathode layer. The orthographic projection of the first transparent conductive layer on the substrate covers the orthographic projection of the first light-emitting stack on the substrate. Forming the first sub-conductive element includes: The first sub-conductive element is formed on the side of the first transparent conductive layer away from the first light-emitting stack.

6. The method for manufacturing a display panel according to claim 2, characterized in that, The second light-emitting unit is formed by: The second light-emitting stack is formed on one side of the second substrate, and the second anode layer is away from the second substrate relative to the second cathode layer; A second transparent conductive layer is formed, the second transparent conductive layer includes a first conductive portion, the orthographic projection of the first conductive portion on the second substrate surrounds the orthographic projection of the second light-emitting stack on the second substrate, and the first conductive portion and the second anode layer are connected; Forming the second sub-conductive element includes: The second sub-conductive element is formed on the side of the first conductive portion away from the second substrate.

7. The method for manufacturing a display panel according to claim 6, characterized in that, Before forming the second transparent conductive layer, the method for manufacturing the display panel further includes: A second transparent insulating layer is formed, the second transparent insulating layer including a fourth insulating portion, a fifth insulating portion and a sixth insulating portion. The fourth insulating portion is stacked on the side of the second substrate near the second light-emitting stack and surrounds the second light-emitting stack. The fifth insulating portion is disposed on the side of the second light-emitting stack. The sixth insulating portion is stacked on the side of the second light-emitting stack away from the second substrate. The fifth insulating portion connects the fourth insulating portion and the sixth insulating portion. A second through hole is formed on the sixth insulating portion, and the second through hole exposes the second light-emitting stack. A first sublayer forming the second transparent dielectric layer is provided, wherein the first conductive portion is stacked on the side of the first sublayer away from the second substrate.

8. The method for manufacturing a display panel according to claim 7, characterized in that, Before forming the first sublayer of the second transparent dielectric layer, the method for fabricating the display panel further includes: A second metal reflective portion is formed, at least a portion of which is located on the side of the sixth insulating portion away from the second light-emitting stack. The second metal reflective element is embedded within the first sub-layer.

9. A display panel, characterized in that, The display panel is a display panel manufactured by the method described in any one of claims 1 to 8, and the display panel comprises: substrate; A plurality of light-emitting pixels are disposed on one side of the substrate along the thickness direction of the substrate, and the plurality of light-emitting pixels are spaced apart. Each light-emitting pixel includes: Multiple light-emitting units are stacked along the thickness direction of the substrate, and two adjacent light-emitting units arranged along the thickness direction of the substrate include: The first light-emitting unit includes a first light-emitting stack, the first light-emitting stack includes a first anode layer, a first cathode layer and a first light-emitting layer, the first anode layer and the first cathode layer are stacked on both sides of the first light-emitting layer; The second light-emitting unit includes a second light-emitting stack, which includes a second anode layer, a second cathode layer, and a second light-emitting layer. The second anode layer and the second cathode layer are stacked on both sides of the second light-emitting layer. The first sub-conductive element extends along the stacking direction and is connected to the first cathode layer. The orthographic projection of the first sub-conductive element on the substrate surrounds the orthographic projection of the first light-emitting stack on the substrate, so that the first sub-conductive element avoids the light emission path of the first light-emitting unit in the normal direction. The second sub-conductive element extends along the stacking direction and protrudes from the second light-emitting unit. The second sub-conductive element is connected to the second anode layer. The orthographic projection of the second sub-conductive element on the substrate surrounds the orthographic projection of the second light-emitting stack on the substrate, so that the second sub-conductive element avoids the light emission path of the second light-emitting unit in the normal direction. The end face of the first sub-conductive component away from the first cathode layer and the end face of the second sub-conductive component protruding from the second light-emitting unit are mixed and bonded, and no bonding layer is provided between the first sub-conductive component and the second sub-conductive component.

10. The display panel according to claim 9, characterized in that, Also includes: A first transparent dielectric layer is stacked on the side of the first light-emitting unit near the first sub-conductive component. The first sub-conductive component is embedded in the first transparent dielectric layer. The end face of the first sub-conductive component away from the first light-emitting unit is flush with the surface of the first transparent dielectric layer away from the first light-emitting unit. A second transparent dielectric layer is stacked on the side of the first transparent dielectric layer away from the substrate. The second sub-conductive element is embedded in the second transparent dielectric layer. The end face of the second sub-conductive element protruding from the side of the second anode layer is flush with the surface of the second transparent dielectric layer away from the second anode layer. The first transparent dielectric layer and the second transparent dielectric layer are mixed and bonded.

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