Full-color miniature light-emitting structure and manufacturing method

Abstract

The invention discloses a full-color miniature light-emitting structure and a manufacturing method. The full-color miniature light-emitting structure comprises a first light-emitting lamination layer, a second light-emitting lamination layer and a third light-emitting lamination layer, wherein the first light-emitting lamination layer comprises a first N-type electrode layer, a first N-type semiconductor layer, a first light-emitting layer, a first P-type semiconductor layer and a first P-type electrode layer which are laminated; the second light-emitting lamination layer is arranged on one side of the first P-type electrode layer and comprises a second P-type electrode layer, a second P-type semiconductor layer, a second light-emitting layer, a second N-type semiconductor layer and a second N-type electrode layer which are laminated; the third light-emitting laminated layer is arranged on one side of the second light-emitting laminated layer and comprises a third P-type electrode layer, a third P-type semiconductor layer, a third light-emitting layer, a third N-type semiconductor layer and a third N-type electrode layer which are laminated; side walls are arranged on the peripheries of the first light-emitting lamination layer, the second light-emitting lamination layer and the third light-emitting lamination layer. The pixel density can be improved, the physical area is reduced, the yield is remarkably improved, the cost is reduced, and the light emitting efficiency is effectively improved.

Description

Technical Field

[0001] This application relates to the field of LED chip technology, and in particular to a full-color micro light-emitting structure and its fabrication method. Background Technology

[0002] Micro-LED display technology miniaturizes and arrays traditional LED structures, using CMOS or TFT to create driving circuits, enabling addressing and individual driving of each pixel. The technical approach for Micro-LED display modules differs depending on the application. For large-screen consumer products such as mobile phones, tablets, computers, and televisions, mass transfer is typically used to transfer and combine red, green, and blue LEDs to form a full-color display. This process is extremely complex and costly. It requires at least three independent mass transfer and bonding processes, demanding extremely high precision (down to the micrometer level), making yield improvement difficult. Furthermore, the failure of a single chip results in a dead pixel on the screen, leading to high repair costs. For AR / VR display products, quantum dot color conversion and three-color prism synthesis technologies are currently used to create full-color display modules. The color conversion scheme uses only one color MicroLED chip (usually blue or ultraviolet), then converts some of the blue / ultraviolet light into red and green light by covering it with quantum dots (QD) or phosphors. Its bottleneck lies in the loss of conversion efficiency, which may lead to uneven brightness or insufficient color purity (especially red light). Furthermore, the stability (light decay) and weather resistance (sensitive to water and oxygen) of quantum dot materials under long-term high brightness are also significant challenges. Another widely used application is optical prism combining, a technology similar to DLP projection, using three monochromatic MicroLED chips, which are combined through a prism before projection. Its bottleneck is the large system size, making it unsuitable for size-sensitive consumer electronics such as mobile phones and AR devices.

[0003] Given the significant challenges of the aforementioned traditional technologies, there is a need to develop a chip structure that can be vertically stacked and independently emit full-color light. Summary of the Invention

[0004] This application provides a full-color micro light-emitting structure and its fabrication method to solve the problems of insufficient pixel density, large size, low yield, and poor luminous efficiency in existing full-color light chip structures.

[0005] The present invention solves the above-mentioned technical problems mainly through the following technical solutions: A full-color micro-light-emitting structure is provided, comprising: The first light-emitting stack includes a first N-type electrode layer, a first N-type semiconductor layer, a first light-emitting layer, a first P-type semiconductor layer, a first ohmic contact layer, and a first P-type electrode layer stacked sequentially. The second light-emitting stack is disposed on the side of the first P-type electrode layer away from the first ohmic contact layer. The second light-emitting stack includes a second P-type electrode layer, a second ohmic contact layer, a second P-type semiconductor layer, a second light-emitting layer, a second N-type semiconductor layer, and a second N-type electrode layer stacked sequentially in a direction away from the first light-emitting stack. The third light-emitting stack is disposed on the side of the second light-emitting stack away from the first light-emitting stack. The third light-emitting stack includes a third P-type electrode layer, a third ohmic contact layer, a third P-type semiconductor layer, a third light-emitting layer, a third N-type semiconductor layer and a third N-type electrode layer stacked sequentially in the direction away from the second light-emitting stack. A first sidewall is provided on one side of the periphery of the first light-emitting stack, the second light-emitting stack, and the third light-emitting stack, respectively electrically connected to the second N-type electrode layer and the third N-type electrode layer. A second sidewall is provided on the other side of the periphery of the first light-emitting stack and the second light-emitting stack, respectively electrically connected to the first P-type electrode layer, the second P-type electrode layer, and the third P-type electrode layer.

[0006] Furthermore, it also includes a driver chip, wherein the first light-emitting stack is formed at the output end of the driver chip, the first N-type electrode layer is connected to the N electrode of the driver chip, the first sidewall is connected to the N electrode of the driver chip, and the second sidewall is connected to the P electrode of the driver chip.

[0007] Furthermore, it also includes a microlens formed on the side of the third light-emitting stack opposite to the second light-emitting stack.

[0008] Furthermore, a shielding sidewall is provided in the insulating layer on the other side of the periphery of the third light-emitting stack, and the first sidewall, the second sidewall and the shielding sidewall together surround the periphery of the first light-emitting stack, the second light-emitting stack and the third light-emitting stack.

[0009] Furthermore, the first sidewall includes an inner sidewall and an outer sidewall, the outer sidewall being disposed around the inner sidewall, the outer sidewall being connected to the third N-type electrode layer, and the inner sidewall being connected to the second N-type electrode layer.

[0010] Furthermore, the inner sidewall is provided with a first metal extension layer, which is disposed on the side of the second N-type electrode layer away from the second N-type semiconductor layer, and the outer sidewall is provided with a second metal extension layer, which is stacked on the side of the third N-type electrode layer away from the third N-type semiconductor layer.

[0011] Furthermore, the second sidewall is provided with a third metal extension layer and a fourth metal extension layer, respectively. The third metal extension layer is disposed on the side of the third P-type electrode layer away from the third ohmic contact layer, and the fourth metal extension layer is disposed between the first P-type electrode layer and the second P-type electrode layer.

[0012] Furthermore, the first light-emitting stack, the second light-emitting stack, and the third light-emitting stack are each provided in multiples, and are stacked in a corresponding manner.

[0013] Furthermore, the first, second, and third light-emitting layers emit different colors.

[0014] The beneficial technical effects of the full-color micro-light-emitting structure of the present invention are as follows: It can effectively increase pixel density, reduce physical area, significantly improve yield and reduce cost, and effectively improve luminous efficiency.

[0015] A method for fabricating a full-color micro-luminescent structure is also provided, including the following steps: The fabrication of a green Micro-LED device structure is as follows: Discrete pixel structures are etched onto the epitaxial surface of the first optical chip; A first N-type electrode layer is formed and a conductive metal is electroplated to obtain a green light chip; The green light chip and the driver chip are hybrid bonded; The first P-type electrode layer was prepared and a conductive metal was electroplated to obtain the green Micro-LED device structure; The fabrication of the blue Micro-LED device structure is as follows: Discrete pixel structures are etched onto the epitaxial surface of the second optical chip; A second P-type electrode layer was prepared and electroplated with conductive metal to obtain a blue light processing chip structure; The green Micro-LED device structure is hybridized and bonded with the blue light processing chip structure; Fabrication of a second N-type electrode layer; The fabrication structure of the red-light Micro-LED device is as follows: Discrete pixel structures are etched onto the epitaxial surface of the third optical chip; A third P-type electrode layer was fabricated to obtain a red light-processed chip structure. The red light processing chip structure is hybridized and bonded with the green light Micro-LED device structure; Fabrication of the third N-type electrode layer; Microlenses are fabricated on the surface of pixels.

[0016] Furthermore, the fabrication of the green Micro-LED device structure specifically includes: The first optical chip epitaxy is selected from sapphire or silicon substrates, and the first optical chip epitaxy includes a first substrate, a first semiconductor transition layer, a first N-type semiconductor layer, a first light-emitting layer, a first P-type semiconductor layer and a first ohmic contact layer stacked in sequence; Discrete pixel structures are etched onto the epitaxial surface of the first optical chip; Temporarily bond the epitaxial layer of the first optical chip to a temporary substrate; The first substrate is stripped and the first semiconductor transition layer is removed; A first N-type electrode layer is formed on the first N-type semiconductor layer, and conductive metal is electroplated to obtain a green light chip; The green light chip and the driver chip are hybrid bonded; Remove the temporary substrate; A first P-type electrode layer is fabricated on the first ohmic contact layer, and a conductive metal is electroplated to obtain a green Micro-LED device structure.

[0017] Furthermore, the fabrication of a first P-type electrode layer on the first ohmic contact layer, followed by electroplating of a conductive metal to obtain a green Micro-LED device structure, includes: Metal is deposited on the first ohmic contact layer to form the first P-type electrode layer; SiO2 is deposited, holes are made above the first P-type electrode layer and the electrodes of the driving chip, and copper is electroplated. The holes are then polished to retain the copper metal, thus obtaining the green Micro-LED device structure.

[0018] Furthermore, the fabrication of the blue Micro-LED device structure specifically includes: The second optical chip epitaxy is selected from sapphire or silicon substrates. The second optical chip epitaxy includes a second substrate, a second semiconductor transition layer, a second N-type semiconductor layer, a second light-emitting layer, a second P-type semiconductor layer and a second ohmic contact layer stacked sequentially. Discrete pixel structures are etched on the epitaxial surface of the second optical chip, with each pixel etched into the second semiconductor transition layer. A second P-type electrode layer is fabricated on the second ohmic contact layer, and a conductive metal is electroplated to obtain a blue light processing chip structure. The green Micro-LED device structure is hybridized and bonded with the blue light processing chip structure; The second substrate is stripped and the second semiconductor transition layer is removed; A second N-type electrode layer is fabricated on the second N-type semiconductor layer.

[0019] Furthermore, the fabrication of a second P-type electrode layer on the second ohmic contact layer, followed by electroplating of a conductive metal to obtain the blue light processing chip structure includes: Metal deposition is performed on the second P-type ohmic contact layer, and current conduction is achieved by evaporating multiple layers of metal to form the second P-type electrode layer. SiO2 is deposited, and holes are made in the second P-type electrode layer. Then, copper electroplating is performed and polishing is carried out to retain the copper plating inside the holes, thus obtaining a blue light processing chip.

[0020] Further, the fabrication of the second N-type electrode layer on the second N-type semiconductor layer includes: The second N-type semiconductor layer and the second light-emitting layer are etched locally, then SiO2 is deposited, and then the surface of the second N-type semiconductor layer is exposed by polishing. Metal deposition is performed on the second N-type semiconductor layer, and current conduction is achieved by evaporating multiple layers of metal to form the second N-type electrode layer; SiO2 is deposited and holes are made in the second N-type electrode layer. Then copper electroplating is performed and polishing is carried out to retain the copper plating inside the holes. SiO2 is deposited again, and holes are made on the second N-type electrode layer and the electrodes of the driver chip. Then, copper electroplating is performed and polishing is carried out to retain the plating inside the holes. SiO2 is deposited again to create holes on the electrodes of the driver chip. After copper electroplating, the holes are polished to retain the copper plating.

[0021] Furthermore, the structure for fabricating the red Micro-LED device is specifically as follows: A third optical chip epitaxy is selected on a sapphire or silicon substrate, the third optical chip epitaxy comprising a third substrate, a third semiconductor transition layer, a third N-type semiconductor layer, a third light-emitting layer, a third P-type semiconductor layer and a third ohmic contact layer stacked sequentially; Discrete pixel structures are etched on the epitaxial surface of the third optical chip, with each pixel etched to the third semiconductor transition layer. A third P-type electrode layer is fabricated on the third ohmic contact layer to obtain a red light processing chip structure; The red light processing chip structure is hybridized and bonded with the green light Micro-LED device structure; The third substrate is stripped and the third semiconductor transition layer is removed; A third N-type electrode layer is fabricated on the third N-type semiconductor layer; Microlenses are fabricated on the surface of pixels.

[0022] Furthermore, the fabrication of a third P-type electrode layer on the third ohmic contact layer to obtain a red light processing chip structure includes: Metal deposition is performed on the third P-type semiconductor layer, and current conduction is achieved by evaporating multiple layers of metal to form the third P-type electrode layer. SiO2 is deposited, and holes are made in the third P-type electrode layer. Then, copper electroplating is performed and polishing is carried out to retain the copper plating inside the holes, thus obtaining the red light processing chip structure.

[0023] Further, the fabrication of the third N-type electrode layer on the third N-type semiconductor layer includes: The third N-type semiconductor layer and the third light-emitting layer are etched locally, SiO2 is deposited again, and polishing is performed to expose the third N-type semiconductor layer; A metal is deposited on the third N-type semiconductor layer to form a third N-type electrode layer; SiO2 is deposited, and holes are made on the third N-type electrode layer and the electrodes of the driving chip. Copper electroplating is performed, polishing is carried out, and the copper plating inside the holes is retained.

[0024] The beneficial technical effects of the method for fabricating the full-color micro-luminescent structure of the present invention are as follows: It can avoid the problems of transfer frequency and complexity caused by mass transfer during the manufacturing process, simplify the manufacturing process, thereby significantly improving the yield of full-color LED devices and reducing the cost of devices. At the same time, the use of sidewall metal can effectively reduce light crosstalk between pixels and significantly improve luminous efficiency. In addition, the vertical stacking manufacturing method can increase pixel density and further reduce physical area on the basis of traditional three-color LED horizontal structure. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the following description of the embodiments will be briefly introduced. Obviously, the accompanying drawings described below are only one embodiment of the present invention.

[0026] Figure 1 This is a cross-sectional view of the full-color micro-light-emitting structure provided in the embodiment of the present invention; Figure 2 This is a cross-sectional view of another embodiment of the full-color micro-light-emitting structure provided in this invention; Figure 3 This is a structural cross-sectional view of another embodiment of the full-color micro-light-emitting structure provided in this invention; Figure 4 This is a cross-sectional view of the structure after the pixels are etched on the outer side of the first optical chip in the method for fabricating a full-color micro light-emitting structure provided in this embodiment of the invention. Figure 5 This is a cross-sectional view of the structure after the green light chip is bonded to the temporary substrate in the method for fabricating a full-color micro light-emitting structure provided in this embodiment of the invention; Figure 6 This is a cross-sectional view of the structure after the first substrate is removed in the fabrication method of the full-color micro light-emitting structure provided in the embodiment of the present invention; Figure 7This is a cross-sectional view of the structure after removing the first semiconductor transition layer in the fabrication method of the full-color micro light-emitting structure provided in the embodiment of the present invention; Figure 8 This is a cross-sectional view of the structure after partial etching of the first N-type semiconductor layer and the first light-emitting layer in the fabrication method of the full-color micro light-emitting structure provided in the embodiment of the present invention; Figure 9 This is a cross-sectional view of the structure after the first N-type electrode layer is formed in the method for fabricating a full-color micro-light-emitting structure provided in this embodiment of the invention; Figure 10 This is a cross-sectional view of the structure after copper electroplating on the first N-type electrode layer in the fabrication method of the full-color micro light-emitting structure provided in the embodiment of the present invention. Figure 11 This is a cross-sectional view of the structure after the green light chip and the driving chip are mixed and bonded in the method for fabricating a full-color micro light-emitting structure provided in the embodiments of the present invention; Figure 12 This is a cross-sectional view of the structure after removing the temporary substrate in the method for fabricating a full-color micro light-emitting structure provided in this embodiment of the invention; Figure 13 This is a cross-sectional view of the structure after forming the first P-type electrode layer and depositing SiO2 in the fabrication method of the full-color micro light-emitting structure provided in the embodiment of the present invention; Figure 14 This is a cross-sectional view of the structure after copper plating on the first P-type electrode layer and the driving chip electrode in the fabrication method of the full-color micro light-emitting structure provided in the embodiment of the present invention. Figure 15 This is a cross-sectional view of the blue light processing chip structure prepared in the fabrication method of the full-color micro light-emitting structure provided in this embodiment of the invention. Figure 16 This is a cross-sectional view of the structure after the green Micro-LED device structure and the blue processing chip structure are mixed and bonded in the method for fabricating a full-color micro-light-emitting structure provided in the embodiments of the present invention; Figure 17 This is a cross-sectional view of the structure after removing the second substrate and the second semiconductor transition layer and performing local etching in the fabrication method of the full-color micro light-emitting structure provided in the embodiment of the present invention; Figure 18 This is a cross-sectional view of the structure after the second N-type electrode layer is formed in the method for fabricating a full-color micro-light-emitting structure provided in this embodiment of the invention; Figure 19 This is a cross-sectional view of the structure after copper plating on the second N-type electrode layer in the fabrication method of the full-color micro light-emitting structure provided in the embodiment of the present invention. Figure 20 This is a cross-sectional view of the structure after holes are opened and copper is electroplated on the second N-type electrode layer and the electrodes of the driving chip in the fabrication method of the full-color micro light-emitting structure provided in the embodiment of the present invention. Figure 21 This is a cross-sectional view of the structure after further drilling holes and electroplating copper on the electrodes of the driver chip in the fabrication method of the full-color micro light-emitting structure provided in the embodiment of the present invention. Figure 22 This is a cross-sectional view of the structure after forming the third P-type electrode layer and electroplating copper in the method for fabricating the full-color micro light-emitting structure provided in the embodiment of the present invention; Figure 23 This is a cross-sectional view of the structure after the red light processing chip structure and the green light Micro-LED device structure are mixed and bonded in the fabrication method of the full-color micro light-emitting structure provided in the embodiment of the present invention; Figure 24 This is a cross-sectional view of the structure after removing the third substrate and the third semiconductor transition layer and performing local etching in the fabrication method of the full-color micro light-emitting structure provided in the embodiment of the present invention; Figure 25 This is a cross-sectional view of the structure after the formation of the third N-type electrode layer in the fabrication method of the full-color micro light-emitting structure provided in the embodiment of the present invention. Detailed Implementation

[0027] 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 of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0028] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0029] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0030] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on" the second feature include the first feature being directly above or diagonally above the second feature, or simply indicating that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature include the first feature being directly below or diagonally below the second feature, or simply indicating that the first feature is at a lower horizontal level than the second feature.

[0031] The following disclosure provides many different embodiments or examples for implementing different structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided in this application, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0032] For details, please refer to Figures 1 to 3This application provides a full-color micro-light-emitting structure. This full-color LED vertical stacking device structure adopts a common-pole three-color LED stacking structure design, eliminating the need for mass transfer and quantum dot color conversion processes. Through vertical stacking, it achieves higher pixel density in a smaller space, effectively increasing pixel density. It further reduces the physical area compared to traditional three-color LED horizontal structures and avoids the problems of transfer frequency, complexity, and yield efficiency associated with mass transfer, potentially significantly improving yield and reducing costs. The design can achieve extremely high pixel density. Simultaneously, using through-hole metal for sidewall reflection eliminates the need for additional reflection processes, saves manufacturing space, and significantly improves luminous efficiency. This full-color LED vertical stacking device structure is mainly applied to Micro LED products requiring high brightness, low crosstalk, and full color, meeting the extreme requirements of near-eye display devices such as AR / VR.

[0033] Specifically, please refer to Figure 1 The full-color micro-light-emitting structure in this embodiment mainly includes: A first light-emitting layer 2, a second light-emitting layer 3, and a third light-emitting layer 4 are vertically stacked, wherein the first light-emitting layer 2, the second light-emitting layer 3, and the third light-emitting layer 4 emit red, blue, and green light, respectively. The first light-emitting layer 2 emits green light, the second light-emitting layer 3 is located between the first light-emitting layer 2 and the third light-emitting layer 4 and emits blue light, and the third light-emitting layer 4 emits red light.

[0034] The first light-emitting stack 2 includes a first N-type electrode layer 21, a first N-type semiconductor layer 22, a first light-emitting layer 23, a first P-type semiconductor layer 24, a first ohmic contact layer 25, and a first P-type electrode layer 26 stacked sequentially. Pixels are formed by etching, and the planar shape of the pixels can be square, circular, or other different shapes.

[0035] The second light-emitting stack 3 includes a second P-type electrode layer 31, a second ohmic contact layer 32, a second P-type semiconductor layer 33, a second light-emitting layer 34, a second N-type semiconductor layer 35, and a second N-type electrode layer 36 stacked sequentially. A pixel is formed by etching, and the planar shape of the pixel can be different, such as square or circular. The second light-emitting stack 3 is formed on the side of the first P-type electrode layer 26 in the first light-emitting stack 2 that faces away from the first ohmic contact layer 25.

[0036] An insulating layer may be filled between the first light-emitting stack 2 and the second light-emitting stack 3. The insulating layer may be one of SiO2, Al2O3, etc.

[0037] The third light-emitting stack 4 includes a third P-type electrode layer 41, a third ohmic contact layer 42, a third P-type semiconductor layer 43, a third light-emitting layer 44, a third N-type semiconductor layer 45, and a third N-type electrode layer 46 stacked sequentially. A pixel is formed by etching, and the planar shape of the pixel can be square, circular, or other shapes. The third light-emitting stack 4 is formed on the side of the second light-emitting stack 3 opposite to the first light-emitting stack 1. An insulating layer is filled between the second light-emitting stack 3 and the third light-emitting stack 4. Specifically, the third light-emitting stack 4 is formed on the side of the second N-type electrode layer 36 in the second light-emitting stack 3 opposite to the second N-type semiconductor layer 35.

[0038] The first light-emitting stack 2 and the second light-emitting stack 3 are bonded using a hybrid bonding method, and the second light-emitting stack 3 and the third light-emitting stack 4 are also bonded using a hybrid bonding method, forming a vertically stacked tri-color LED stacked device. Specifically, the first P-type electrode layer 26 in the first light-emitting stack 2 and the second P-type electrode layer 31 in the second light-emitting stack 3 are hybrid-bonded, and the insulating layers of the second light-emitting stack 2 are hybrid-bonded with each other.

[0039] A first sidewall is provided on one side of the periphery of the first light-emitting stack 2, the second light-emitting stack 3, and the third light-emitting stack 4. This first sidewall is electrically connected to the second N-type electrode layer 36 and the third N-type electrode layer 46. Simultaneously, this first sidewall forms a light-reflecting structure around the pixel, preventing light emitted from the pixel from exiting through this side and interfering with neighboring pixels, thus effectively improving luminous efficiency. Meanwhile, a second sidewall a is provided on the other side of the periphery of the first light-emitting stack 2 and the second light-emitting stack 3. This second sidewall is electrically connected to the three P-type electrodes of the first P-type electrode layer 26, the second P-type electrode layer 31, and the third P-type electrode layer 41, forming a common P-structure of the three light-emitting stacks. This second sidewall also forms a light-reflecting structure around the pixel, preventing light emitted from the pixel from exiting through this side and interfering with neighboring pixels, thus effectively improving luminous efficiency. The first and second sidewalls together completely surround the periphery of a single stacked pixel of the first light-emitting stack 2, the second light-emitting stack 3, and the third light-emitting stack 4, thus realizing reflective sidewalls of the stacked pixels and improving optical crosstalk.

[0040] More specifically, the first sidewall includes an inner sidewall b and an outer sidewall c, wherein the outer sidewall is disposed around the inner sidewall and is mainly connected to the third N-type electrode layer 46 to achieve electrical conduction, and the inner sidewall is mainly connected to the second N-type electrode layer 36 to achieve electrical conduction.

[0041] Furthermore, a first metal extension layer extending toward the pixel is provided on the inner sidewall. The first metal extension layer extends to the surface of the second N-type electrode layer 36 opposite to the second N-type semiconductor layer 35. A second metal extension layer extending toward the pixel is provided on the outer sidewall. The second metal extension layer extends to the surface of the third N-type electrode layer 46 opposite to the third N-type semiconductor layer 45. This forms an independent connection between the N-type electrodes of each light-emitting stack and the light reflection isolation formed around the light-emitting stack and between pixels, thus improving the light crosstalk phenomenon between pixels.

[0042] Furthermore, a third metal extension layer and a fourth metal extension layer are respectively provided on the second sidewall. The third metal extension layer extends towards the pixel and extends to the side of the third P-type electrode layer 41 opposite to the third ohmic contact layer 42. The fourth metal extension layer extends towards the pixel and extends to the side between the first P-type electrode layer 26 and the second P-type electrode layer 31, serving as a bonding layer for the two P-type electrodes. The second sidewall and the corresponding metal extension layer are used to achieve the connection and conduction between the P-type electrodes of the three light-emitting stacks. The three sidewalls together surround the periphery of the pixel, and the ends of the sidewalls overlap each other, forming a 360° light reflection effect without dead angles in the circumferential direction.

[0043] The first and second sidewalls include, but are not limited to, Ti, Al, Au, Pt, Ni, Al, etc.

[0044] In addition, a shielding sidewall d is provided in the insulating layer on the other side of the third light-emitting stack 4. This shielding layer shields the area not covered by the first and second sidewalls, and together with the first and second sidewalls, forms a 360° surround around the stacked pixels to avoid local light crosstalk.

[0045] The material of the shielding layer can include, but is not limited to, highly matting materials such as black adhesive. These materials, due to their excellent light-shielding properties and good process adaptability, can effectively block light penetration, ensuring that the light-shielding effect meets design requirements. Furthermore, depending on different product needs and usage environments, other composite materials or coating technologies with similar optical properties can be considered to meet even more stringent light-shielding performance indicators. Of course, the material of the shielding layer can include, but is not limited to, highly reflective metals such as silver or aluminum; for example, the shielding layer can specifically be a silver foil layer or an aluminum foil layer. Understandably, compared to light-shielding layers formed by photoresist, there are issues with high light absorption and significant light energy loss.

[0046] In this embodiment, the semiconductor transition layer involved in the three light-emitting layers can be an undoped gallium nitride layer, the N-type semiconductor layer can be an N-type gallium nitride layer or an N-type gallium arsenide layer, and the light-emitting layer can be a quantum well layer, such as an indium gallium nitride quantum well layer, or an indium gallium nitride / gallium nitride multi-quantum well layer. The P-type semiconductor layer can be a P-type gallium nitride layer or a P-type gallium arsenide layer.

[0047] In some embodiments, see Figure 2 The full-color micro-light-emitting structure also includes a driver chip 1. The driver chip 3 has a P-electrode and multiple N-electrodes at its output terminal. A first light-emitting stack 2 is formed at the output terminal of the driver chip 1. A first N-type electrode layer 21 in the first light-emitting stack 2 is bonded to the N-electrode of the driver chip 1. A first sidewall is connected to the N-electrode of the driver chip 1, and a second sidewall is connected to the P-electrode of the driver chip 1. Specifically, the inner and outer sidewalls are connected to different N-electrodes of the driver chip 1, respectively. An insulating layer can be filled between the first light-emitting stack 2 and the driver chip 1. It should be further explained that the aforementioned outer sidewall is mainly connected to one corresponding N electrode of the driver chip 1 and the third N-type electrode layer 46 to achieve conductivity, and the inner sidewall is mainly connected to another corresponding N electrode of the driver chip 1 and the second N-type electrode layer 36 to achieve conductivity. That is, the electrical connection between the third N-type electrode layer 46 and the second N-type electrode layer 36 and the corresponding N electrode of the driver chip 1 is achieved through the two sidewalls.

[0048] In some embodiments, see Figure 3 The full-color micro-light-emitting structure also includes a microlens 6, which is formed on the side of the third light-emitting stack 4 opposite to the second light-emitting stack 3. This microlens 6 effectively reduces light loss and enhances brightness.

[0049] In this embodiment, the method for fabricating the full-color micro-light-emitting structure mainly includes the following: Temporary bonding of green epitaxial wafers; The green epitaxial wafer is stripped from its substrate and then structurally processed. Green light film pixel structure sheet and driving hybrid bonding; Backside processing of green epitaxial pixel structure sheet; Blue light epitaxial pixel structure sheet fabrication; The blue light pixel structure sheet is mixed and bonded with green light, and then the blue light substrate is removed; Backside processing of blue light epitaxial pixel structure sheet; Red light epitaxial pixel structure sheet processing; After the red light pixel structure sheet is mixed and bonded with blue light, the red light substrate is removed. Microlenses are fabricated on stacked pixels.

[0050] Specifically as follows: S1. Fabricate the green Micro-LED device structure as follows: S111. Select a first optical chip epitaxy on a sapphire or silicon substrate, wherein the first optical chip epitaxy includes a first substrate (e in the figure), a first semiconductor transition layer (f in the figure), a first N-type semiconductor layer, a first light-emitting layer, a first P-type semiconductor layer and a first ohmic contact layer stacked sequentially. S112. An etching mask layer is deposited on the surface of the first ohmic contact layer, wherein the etching mask layer includes, but is not limited to, photoresist, metal, insulating layer and other etching-resistant materials or combinations thereof. S113. Discrete pixel structures are etched on the epitaxial surface of the first optical chip. Specifically, the ISO structure is etched for each pixel, the first N-shaped semiconductor layer between each pixel is cleaned, and electrical and physical isolation is formed (see...). Figure 4 ); S114. Temporarily bond the epitaxial layer of the first optical chip to the temporary substrate (see...) Figure 5 (In the figure, g refers to the temporary substrate). S115. Remove the first substrate and etch the first semiconductor layer cleanly to expose the first N-type semiconductor layer (see...). Figure 6 and Figure 7 ); S116. Etch the first N-type semiconductor layer and the first light-emitting layer in a local area of ​​a single pixel, while retaining the first P-type semiconductor layer (see...). Figure 8 ); S117. SiO2 is deposited. Then, a window is opened on the first N-type semiconductor layer and metal deposition is performed. Current conduction is achieved by evaporating multiple metal layers. The metal layers include, but are not limited to, Ti, Al, Au, Pt, Ni, Al, etc. A seed metal layer is deposited on the metal, and the seed layer includes, but is not limited to, TaN, TiN, forming the first N-type electrode layer (see...). Figure 9 ); S118. SiO2 is deposited on the first N-type electrode layer, and holes are made locally in the first N-type electrode layer. Copper electroplating is performed, followed by polishing, while retaining the copper in the hole area to obtain the green light chip (see...). Figure 10 ); S119. The green light chip and driver chip are pretreated by means of formic acid and DI water to remove the oxide layer on the surface of the copper electrode and improve the surface hydrophilicity and bonding strength. S120. The green light chip and the driver chip are hybrid bonded. The bonding conditions involve applying a certain pressure at 300℃-800℃ and maintaining it for a certain time. After annealing in a nitrogen annealing furnace for a certain time, the hybrid bonding between copper-copper and SiO2-SiO2 is completed (see...). Figure 11 ); S121. Contact bonding and removal of the temporary substrate, and removal of the temporary bonding adhesive by dry or wet method (see...). Figure 12 ); S122. Deposit metal on the first ohmic contact layer, and form current conduction by evaporating multiple layers of metal. The metal layer includes, but is not limited to, Ti, Al, Au, Pt, Ni, Al, etc., and deposit a seed layer metal on the metal. The seed layer includes, but is not limited to, TaN, TiN, etc., to form the first P-type electrode layer. S123, deposited SiO2 (see reference) Figure 13 A hole is made above the first P-type electrode layer and the electrodes of the driver chip, and copper is electroplated on it. Then, the hole is polished to retain the copper metal inside, thus obtaining the green Micro-LED device structure (see [reference]). Figure 14 ).

[0051] S2. Fabricate the structure of the blue Micro-LED device, as follows: S211. Select a second optical chip epitaxy on a sapphire or silicon substrate, wherein the second optical chip epitaxy includes a second substrate (h in the figure), a second semiconductor transition layer (i in the figure), a second N-type semiconductor layer, a second light-emitting layer, a second P-type semiconductor layer, and a second ohmic contact layer stacked sequentially. S212. An etching mask layer is deposited on the surface of the first ohmic contact layer, wherein the etching mask layer includes, but is not limited to, photoresist, metal, insulating layer and other etching-resistant materials or combinations thereof; S213. A discrete pixel structure is etched on the epitaxial surface of the first optical chip. Specifically, the ISO structure is etched for each pixel, the second N-shaped semiconductor layer between each pixel is etched clean, and electrical and physical isolation is formed. S214. Metal deposition is performed on the P-type ohmic contact layer, and current conduction is formed by evaporating multiple layers of metal. The metal layers include, but are not limited to, Ti, Al, Au, Pt, Ni, Al, etc., and a seed layer metal is deposited on the metal. The seed layer includes, but is not limited to, TaN, TiN, to form a second P-type electrode layer. S215, SiO2 is deposited, and holes are made in the second P-type electrode layer. Then, copper electroplating is performed, followed by polishing to retain the copper plating inside the holes, resulting in a blue light processing chip (see...). Figure 15 ); S216, Hybrid bonding of green Micro-LED device structure with blue light processing chip structure (see...) Figure 16 ); S217. Peel off the second substrate and remove the second semiconductor transition layer. The removal method includes, but is not limited to, dry removal. S218. The second N-type semiconductor layer and the second light-emitting layer are etched locally, then SiO2 is deposited, and then the surface of the second N-type semiconductor layer is exposed by polishing (see...). Figure 17 ); S219. Metal deposition is performed on the second N-type semiconductor layer, and current conduction is formed by evaporating multiple metal layers. The metal layers include, but are not limited to, Ti, Al, Au, Pt, Ni, Al, etc., and a seed metal layer is deposited on the metal, the seed layer including but not limited to TaN, TiN, etc., to form the second N-type electrode layer (see...). Figure 18 ); S220, SiO2 deposition, and opening holes in the second N-type electrode layer, followed by copper electroplating and polishing to retain the copper plating inside the holes (see...). Figure 19 ); S221. SiO2 is deposited again, and holes are made on the second N-type electrode layer and the electrodes (including P and N electrodes) of the driver chip. Then, copper electroplating is performed, followed by polishing to retain the plating inside the holes (see...). Figure 20 ); S222, redeposit SiO2 to create holes on the electrodes (including P and N electrodes) of the driver chip, then perform copper electroplating and polishing to retain the copper plating inside the holes (see...). Figure 21 ); S3. Fabrication of the red Micro-LED device structure, as follows: S311. Select a third optical chip epitaxy on a sapphire or silicon substrate, wherein the third optical chip epitaxy includes a third substrate (j in the figure), a third semiconductor transition layer (k in the figure), a third N-type semiconductor layer, a third light-emitting layer, a third P-type semiconductor layer and a third ohmic contact layer stacked sequentially. S312. Deposit an etching mask layer on the epitaxial surface of the third optical chip. The etching mask layer includes, but is not limited to, photoresist, metal, insulating layer and other etching-resistant materials or combinations thereof. S313. A discrete pixel structure is etched on the epitaxial surface of the first optical chip. Specifically, the ISO structure is etched for each pixel, the third N-shaped semiconductor layer between each pixel is etched clean, and electrical and physical isolation is formed, and the etching extends to the third semiconductor transition layer. S314. Metal deposition is performed on the third P-type semiconductor layer, and current conduction is formed by evaporating multiple layers of metal. The metal layers include, but are not limited to, Ti, Al, Au, Pt, Ni, Al, etc., and a seed layer metal is deposited on the metal. The seed layer includes, but is not limited to, TaN, TiN, to form the third P-type electrode layer. S315, SiO2 is deposited, and holes are made on the third P-type electrode layer. Then, copper electroplating is performed, followed by polishing to retain the copper plating inside the holes, resulting in a red light processing chip structure (see...). Figure 22 ); S316, Hybrid bonding of red light processing chip structure and green light Micro-LED device structure (see...) Figure 23 ); S317. Strip the third substrate and remove the third semiconductor transition layer. The removal method includes, but is not limited to, dry removal. S318. Etch the local third N-type semiconductor layer and the third light-emitting layer, then deposit SiO2, and finally polish to expose the surface of the third N-type semiconductor layer (see...). Figure 24 ); S319. Metal deposition is performed on the third N-type semiconductor layer, and current conduction is formed by evaporating multiple metal layers. The metal layers include, but are not limited to, Ti, Al, Au, Pt, Ni, Al, etc., and a seed metal layer is deposited on the metal, the seed layer including but not limited to TaN, TiN, etc., to form the third N-type electrode layer (see...). Figure 25 ); S320, deposit SiO2, and make holes on the third N-type electrode layer and the electrode (N electrode) of the driver chip, perform copper electroplating, polish, and retain the copper plating inside the holes (see Figure 2 ).

[0052] In some embodiments, a microlens is also fabricated on the surface of the stacked pixels (i.e., the side of the third light-emitting stack facing away from the second light-emitting stack).

[0053] It is particularly important to emphasize that when the first light-emitting stack is bonded to the electrode layer of the driver chip and / or the second light-emitting stack is bonded to the electrode layer of the first light-emitting stack, electroplated copper is used as the bonding underlayer. Metals (In, Sn, etc.) can be deposited on the surface of the bonding underlayer, or ACF conductive adhesive can be applied to form a bonding layer.

[0054] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0055] The foregoing has provided a detailed description of a full-color micro-light-emitting structure and its fabrication method provided in the embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. 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 full-color micro-luminescent structure, characterized in that, include: The first light-emitting stack includes a first N-type electrode layer, a first N-type semiconductor layer, a first light-emitting layer, a first P-type semiconductor layer, a first ohmic contact layer, and a first P-type electrode layer stacked sequentially. The second light-emitting stack is disposed on the side of the first P-type electrode layer away from the first ohmic contact layer. The second light-emitting stack includes a second P-type electrode layer, a second ohmic contact layer, a second P-type semiconductor layer, a second light-emitting layer, a second N-type semiconductor layer, and a second N-type electrode layer stacked sequentially in a direction away from the first light-emitting stack. The third light-emitting stack is disposed on the side of the second light-emitting stack away from the first light-emitting stack. The third light-emitting stack includes a third P-type electrode layer, a third ohmic contact layer, a third P-type semiconductor layer, a third light-emitting layer, a third N-type semiconductor layer and a third N-type electrode layer stacked sequentially in the direction away from the second light-emitting stack. A first sidewall is provided on one side of the periphery of the first light-emitting stack, the second light-emitting stack, and the third light-emitting stack, respectively electrically connected to the second N-type electrode layer and the third N-type electrode layer. A second sidewall is provided on the other side of the periphery of the first light-emitting stack and the second light-emitting stack, respectively electrically connected to the first P-type electrode layer, the second P-type electrode layer, and the third P-type electrode layer.

2. The full-color micro-light-emitting structure according to claim 1, characterized in that: It also includes a driver chip, wherein the first light-emitting stack is formed at the output end of the driver chip, the first N-type electrode layer is connected to the N electrode of the driver chip, the first sidewall is connected to the N electrode of the driver chip, and the second sidewall is connected to the P electrode of the driver chip.

3. The full-color micro-light-emitting structure according to claim 1 or 2, characterized in that: It also includes microlenses formed on the side of the third light-emitting stack opposite to the second light-emitting stack.

4. The full-color micro-light-emitting structure according to claim 1, characterized in that: The insulating layer on the other side of the third light-emitting stack is provided with a shielding sidewall, and the first sidewall, the second sidewall and the shielding sidewall together surround the periphery of the first light-emitting stack, the second light-emitting stack and the third light-emitting stack.

5. The full-color micro-light-emitting structure according to claim 1, characterized in that: The first sidewall includes an inner sidewall and an outer sidewall. The outer sidewall is disposed around the inner sidewall and is connected to the third N-type electrode layer. The inner sidewall is connected to the second N-type electrode layer.

6. The full-color micro-light-emitting structure according to claim 5, characterized in that: The inner sidewall is provided with a first metal extension layer, which is disposed on the side of the second N-type electrode layer away from the second N-type semiconductor layer. The outer sidewall is provided with a second metal extension layer, which is stacked on the side of the third N-type electrode layer away from the third N-type semiconductor layer.

7. The full-color micro-light-emitting structure according to claim 1 or 6, characterized in that: The second sidewall is provided with a third metal extension layer and a fourth metal extension layer respectively. The third metal extension layer is disposed on the side of the third P-type electrode layer away from the third ohmic contact layer, and the fourth metal extension layer is disposed between the first P-type electrode layer and the second P-type electrode layer.

8. The full-color micro-light-emitting structure according to claim 1 or 2, characterized in that: The first light-emitting stack, the second light-emitting stack, and the third light-emitting stack are each provided in multiples, and are stacked in a corresponding manner.

9. The full-color micro-light-emitting structure according to claim 1 or 2, characterized in that: The first, second, and third light-emitting layers emit different colors.

10. A method for fabricating a full-color micro-luminescent structure, characterized in that, Includes the following steps: The fabrication of a green Micro-LED device structure is as follows: Discrete pixel structures are etched onto the epitaxial surface of the first optical chip; A first N-type electrode layer is formed and a conductive metal is electroplated to obtain a green light chip; The green light chip and the driver chip are hybrid bonded; The first P-type electrode layer was prepared and a conductive metal was electroplated to obtain the green Micro-LED device structure; The fabrication of the blue Micro-LED device structure is as follows: Discrete pixel structures are etched onto the epitaxial surface of the second optical chip; A second P-type electrode layer was prepared and electroplated with conductive metal to obtain a blue light processing chip structure; The green Micro-LED device structure is hybridized and bonded with the blue light processing chip structure; Fabrication of a second N-type electrode layer; The fabrication structure of the red-light Micro-LED device is as follows: Discrete pixel structures are etched onto the epitaxial surface of the third optical chip; A third P-type electrode layer was fabricated to obtain a red light-processed chip structure. The red light processing chip structure is hybridized and bonded with the green light Micro-LED device structure; Fabrication of the third N-type electrode layer; Microlenses are fabricated on the surface of pixels.

11. The method for fabricating a full-color micro-luminescent structure according to claim 10, characterized in that, The fabrication of the green Micro-LED device structure is specifically as follows: The first optical chip epitaxy is selected from sapphire or silicon substrates, and the first optical chip epitaxy includes a first substrate, a first semiconductor transition layer, a first N-type semiconductor layer, a first light-emitting layer, a first P-type semiconductor layer and a first ohmic contact layer stacked in sequence; Discrete pixel structures are etched onto the epitaxial surface of the first optical chip; Temporarily bond the epitaxial layer of the first optical chip to a temporary substrate; The first substrate is stripped and the first semiconductor transition layer is removed; A first N-type electrode layer is formed on the first N-type semiconductor layer, and conductive metal is electroplated to obtain a green light chip; The green light chip and the driver chip are hybrid bonded; Remove the temporary substrate; A first P-type electrode layer is fabricated on the first ohmic contact layer, and a conductive metal is electroplated to obtain a green Micro-LED device structure.

12. The method for fabricating a full-color micro-luminescent structure according to claim 11, characterized in that, The process of removing the first substrate and the first semiconductor transition layer, forming a first N-type electrode layer on the first N-type semiconductor layer, and electroplating conductive metal to obtain a green light chip includes: Remove the first substrate, etch the first semiconductor transition layer clean to expose the first N-type semiconductor layer; The first N-type semiconductor layer and the first light-emitting layer in a local area are etched, while the first P-type semiconductor layer is retained; SiO2 is deposited, windows are opened on the first N-type semiconductor layer and metal deposition is performed, and current conduction is formed by evaporating multiple layers of metal to form the first N-type electrode layer. SiO2 is deposited on the first N-type electrode layer, and holes are made locally in the first N-type electrode layer for copper electroplating, followed by polishing, while retaining the copper in the hole area to obtain a green light chip.

13. The method for fabricating a full-color micro-luminescent structure according to claim 11, characterized in that, The process of fabricating a first P-type electrode layer on the first ohmic contact layer and electroplating a conductive metal to obtain a green Micro-LED device structure includes: Metal is deposited on the first ohmic contact layer to form the first P-type electrode layer; SiO2 is deposited, holes are made above the first P-type electrode layer and the electrodes of the driving chip, and copper is electroplated. The holes are then polished to retain the copper metal, thus obtaining the green Micro-LED device structure.

14. The method for fabricating a full-color micro-luminescent structure according to claim 10, characterized in that, The fabrication of the blue Micro-LED device structure is specifically as follows: The second optical chip epitaxy is selected from sapphire or silicon substrates. The second optical chip epitaxy includes a second substrate, a second semiconductor transition layer, a second N-type semiconductor layer, a second light-emitting layer, a second P-type semiconductor layer and a second ohmic contact layer stacked sequentially. Discrete pixel structures are etched on the epitaxial surface of the second optical chip, with each pixel etched into the second semiconductor transition layer. A second P-type electrode layer is fabricated on the second ohmic contact layer, and a conductive metal is electroplated to obtain a blue light processing chip structure. The green Micro-LED device structure is hybridized and bonded with the blue light processing chip structure; The second substrate is stripped and the second semiconductor transition layer is removed; A second N-type electrode layer is fabricated on the second N-type semiconductor layer.

15. The method for fabricating a full-color micro-luminescent structure according to claim 14, characterized in that, The process of fabricating a second P-type electrode layer on the second ohmic contact layer and electroplating a conductive metal to obtain a blue light processing chip structure includes: Metal deposition is performed on the second P-type ohmic contact layer, and current conduction is achieved by evaporating multiple layers of metal to form the second P-type electrode layer. SiO2 is deposited, and holes are made in the second P-type electrode layer. Then, copper electroplating is performed and polishing is carried out to retain the copper plating inside the holes, thus obtaining a blue light processing chip.

16. The method for fabricating a full-color micro-luminescent structure according to claim 14, characterized in that, The fabrication of the second N-type electrode layer on the second N-type semiconductor layer includes: The second N-type semiconductor layer and the second light-emitting layer are etched locally, then SiO2 is deposited, and then the surface of the second N-type semiconductor layer is exposed by polishing. Metal deposition is performed on the second N-type semiconductor layer, and current conduction is achieved by evaporating multiple layers of metal to form the second N-type electrode layer; SiO2 is deposited and holes are made in the second N-type electrode layer. Then copper electroplating is performed and polishing is carried out to retain the copper plating inside the holes. SiO2 is deposited again, and holes are made on the second N-type electrode layer and the electrodes of the driver chip. Then, copper electroplating is performed and polishing is carried out to retain the plating inside the holes. SiO2 is deposited again to create holes on the electrodes of the driver chip. After copper electroplating, the holes are polished to retain the copper plating.

17. The method for fabricating a full-color micro-luminescent structure according to claim 10, characterized in that, The fabrication structure of the red-light Micro-LED device is specifically as follows: A third optical chip epitaxy is selected on a sapphire or silicon substrate, the third optical chip epitaxy comprising a third substrate, a third semiconductor transition layer, a third N-type semiconductor layer, a third light-emitting layer, a third P-type semiconductor layer and a third ohmic contact layer stacked sequentially; Discrete pixel structures are etched on the epitaxial surface of the third optical chip, with each pixel etched to the third semiconductor transition layer. A third P-type electrode layer is fabricated on the third ohmic contact layer to obtain a red light processing chip structure; The red light processing chip structure is hybridized and bonded with the green light Micro-LED device structure; The third substrate is stripped and the third semiconductor transition layer is removed; A third N-type electrode layer is fabricated on the third N-type semiconductor layer; Microlenses are fabricated on the surface of pixels.

18. The method for fabricating a full-color micro-luminescent structure according to claim 17, characterized in that, The process of fabricating a third P-type electrode layer on the third ohmic contact layer to obtain a red light processing chip structure includes: Metal deposition is performed on the third P-type semiconductor layer, and current conduction is achieved by evaporating multiple layers of metal to form the third P-type electrode layer. SiO2 is deposited, and holes are made in the third P-type electrode layer. Then, copper electroplating is performed and polishing is carried out to retain the copper plating inside the holes, thus obtaining the red light processing chip structure.

19. The method for fabricating a full-color micro-light-emitting structure according to claim 18, characterized in that, The fabrication of the third N-type electrode layer on the third N-type semiconductor layer includes: The third N-type semiconductor layer and the third light-emitting layer are etched locally, SiO2 is deposited again, and polishing is performed to expose the third N-type semiconductor layer; A metal is deposited on the third N-type semiconductor layer to form a third N-type electrode layer; SiO2 is deposited, and holes are made on the third N-type electrode layer and the electrodes of the driving chip. Copper electroplating is performed, polishing is carried out, and the copper plating inside the holes is retained.

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