RGB micro-led chip and manufacturing method thereof

Abstract

The application provides an RGB Micro-LED chip and a manufacturing method thereof, wherein the RGB Micro-LED chip comprises: a plurality of pixel units, each of which comprises: a conductive substrate; and an RGB stack structure stacked on the surface of the conductive substrate, wherein the RGB stack structure comprises red light emitting structures, green light emitting structures and blue light emitting structures which are sequentially stacked in a first direction and are distributed in a stepped manner, and red light mesas, green light mesas and blue light mesas are exposed; the vertical stacking manner can reduce the size of each group of RGB Micro-LED chips and improve the display resolution; and the wavelength of each light emitting structure gradually decreases along the light emitting direction, and in combination with the setting of the metal reflector, the emitted light of each light emitting structure is emitted along the light emitting direction, so that the emitted light of the short-wavelength light emitting structure is not absorbed by the long-wavelength light emitting structure, thereby improving the light emitting efficiency of the RGB Micro-LED chip.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of light emitting diode, more particularly to an RGB Micro-LED chip and a manufacturing method thereof. BACKGROUND

[0002] With the innovation and development of LED technology, RGB Micro-LED display technology has become a new generation of display technology. The traditional LED structure is miniaturized and matrixed, so that the size of each LED chip is reduced to tens of microns or even microns, and each LED pixel point is addressed and individually driven to emit light. Since the micro-display of the RGB Micro-LED chip has the advantages of high resolution, high brightness, long service life, wide operating temperature range, strong anti-interference ability, fast response speed and low power consumption, the RGB Micro-LED has important application value in high-resolution display, helmet display, augmented reality, high-speed visible light communication, micro-projector, optical genetics and wearable electronics.

[0003] A full-color LED display screen is assembled by RGB Micro-LED chips of red, green and blue (RGB) in a certain arrangement on a substrate. Since the size of the RGB Micro-LED chip is small, a large number of RGB Micro-LEDs need to be transferred to manufacture a full-color RGB Micro-LED display screen, and the process is too complex, which leads to great difficulty in transferring, low yield in mass production, high production cost, poor consistency and other problems. Moreover, the final size and resolution of the full-color LED display screen are restricted by the size and pitch of each group of RGB Micro-LED chips. In general, the traditional RGB uses three chips of red, green and blue arranged uniformly and spaced apart in the horizontal plane to form an RGB effect. Not only is the size of each group large, but the spacing between the single chips of adjacent RGB Micro-LED chips in each group is small, which easily causes color mixing and low resolution. Therefore, there are great difficulties in realizing high resolution and large-scale transfer process of the display screen. SUMMARY

[0004] Therefore, the present application provides an RGB Micro-LED chip and a manufacturing method thereof to solve the problem of small spacing between single chips and small distance between groups of RGB Micro-LED chips in the prior art, which causes color mixing and low resolution. Moreover, the manufacturing process is too complex, which leads to great difficulty in large-scale transfer, low yield in mass production, high production cost, poor consistency and other problems.

[0005] To achieve the above object, the technical scheme adopted by the present application is as follows:

[0006] An RGB Micro-LED chip, characterized in comprising:

[0007] a plurality of pixel units, each of which comprises:

[0008] a conductive substrate;

[0009] an RGB stack structure laminated on the surface of the conductive substrate, the RGB stack structure comprising red light emitting structures, green light emitting structures and blue light emitting structures which are sequentially stacked and distributed in a stepped manner along a first direction, and exposing red light terraces, green light terraces and blue light terraces, the red light emitting structures comprising a first metal mirror, a red light P-type semiconductor layer, a red light active region and a red light N-type semiconductor layer which are laminated sequentially along the first direction; the green light emitting structures comprising a second metal mirror, a green light P-type semiconductor layer, a green light active region and a green light N-type semiconductor layer which are laminated sequentially along the first direction; the blue light emitting structures comprising a third metal mirror, a blue light P-type semiconductor layer, a blue light active region and a blue light N-type semiconductor layer which are laminated sequentially along the first direction, the first direction being perpendicular to the conductive substrate and pointing from the conductive substrate to the blue light emitting structures;

[0010] the red light emitting structures, the green light emitting structures and the blue light emitting structures are connected in series by the respective metal mirrors;

[0011] a first electrode arranged on the side surface of the conductive substrate away from the RGB stack structure;

[0012] a second electrode laminated on the blue light terrace;

[0013] a third electrode connected with the green light emitting structures and the blue light emitting structures and arranged at a distance from the side walls of the green light emitting structures and the blue light emitting structures;

[0014] a fourth electrode connected with the red light emitting structures and the green light emitting structures and arranged at a distance from the side walls of the red light emitting structures and the green light emitting structures;

[0015] an insulating protective layer covering the RGB stack structure and the exposed surface of the conductive substrate, and exposing the second electrode, the third electrode and the fourth electrode.

[0016] Optionally, the third electrode is laminated on the green light terrace, and the fourth electrode is laminated on the red light terrace.

[0017] Optionally, the blue light mesa is provided with a groove extending to the third metal mirror, exposing part of the third metal mirror to form a third metal mirror mesa; the third metal mirror mesa is provided with a groove extending to the second metal mirror, exposing part of the second metal mirror to form a second metal mirror mesa; the third electrode covers the third metal mirror mesa, and the fourth electrode covers the second metal mirror mesa.

[0018] Optionally, the first electrode is a P-type electrode, the second electrode is an N-type electrode, and the third electrode and the fourth electrode can be P-type electrodes or N-type electrodes.

[0019] Optionally, the projection area of the red light emitting structure in the vertical direction is S1, the projection area of the green light emitting structure in the vertical direction is S2, and the projection area of the blue light emitting structure in the vertical direction is S3, then S1>S2>S3.

[0020] Optionally, the insulating protective layer includes a transparent insulating layer and a DBR insulating layer, the transparent insulating layer covers the exposed surfaces of the red light mesa, the green light mesa and the blue light mesa, and the DBR insulating layer covers the sidewalls of the RGB stacked structure and the conductive substrate.

[0021] The application also provides a manufacturing method of an RGB Micro-LED chip, characterized by comprising the following steps:

[0022] Step S1, epitaxially forming a red light stacked structure on a first temporary substrate, a green light stacked structure on a second temporary substrate, and a blue light stacked structure on a third temporary substrate;

[0023] Step S2, providing a conductive substrate;

[0024] Step S3, manufacturing a first electrode on one side surface of the conductive substrate;

[0025] Step S4: An RGB stacked structure is formed on the surface of the conductive substrate away from the first electrode. The RGB stacked structure includes a red light-emitting structure, a green light-emitting structure, and a blue light-emitting structure stacked sequentially along a first direction and arranged in a stepped manner, exposing the red light mesa, the green light mesa, and the blue light mesa. The red light-emitting structure includes, along the first direction, a first metal reflector, a red P-type semiconductor layer, a red active region, and a red N-type semiconductor layer stacked sequentially. The green light-emitting structure includes, along the first direction, a second metal reflector, a green P-type semiconductor layer, a green active region, and a green N-type semiconductor layer stacked sequentially. The blue light-emitting structure includes, along the first direction, a third metal reflector, a blue P-type semiconductor layer, a blue active region, and a blue N-type semiconductor layer stacked sequentially. The first direction is perpendicular to the conductive substrate and extends from the conductive substrate to the blue light-emitting structure.

[0026] The red light emitting structure, the green light emitting structure, and the blue light emitting structure are connected in series in pairs via metal mirrors;

[0027] Step S4 specifically includes the following procedures:

[0028] Step S4.1: Bond the red light stacked structure onto the conductive substrate using the first metal reflector;

[0029] Step S4.2: Remove the first temporary substrate;

[0030] Step S4.3: Adhere the first electrode to the first temporary carrier plate using adhesive.

[0031] Step S4.4: Etch along the surface of the red N-type semiconductor layer to expose the first temporary carrier, forming a first dicing path, and separating the red stacked structure into multiple independent red light emitting structures;

[0032] Step S4.5: By etching and film expansion, the green light stacking structure is separated into multiple independent green light emitting structures, and the distance between each green light emitting structure reaches a first preset length.

[0033] Step S4.6: By etching and film expansion, the blue light stacking structure is separated into multiple independent blue light emitting structures, and the distance between each blue light emitting structure reaches a second preset length;

[0034] Step S4.7: Using the second metal mirror and the red N-type semiconductor layer, each of the green light emitting structures is aligned and bonded to each of the red light emitting structures to expose the red light mesa, and the second temporary substrate is peeled off.

[0035] Step S4.8, respectively aligning each of the blue light emitting structures on each of the green light emitting structures through the third metal mirror and the green light N-type semiconductor layer, exposing a green light mesa, and peeling off the third temporary substrate, exposing a blue light mesa;

[0036] Step S5, making a second electrode, a third electrode and a fourth electrode;

[0037] A second electrode is laminated on the blue light mesa;

[0038] A third electrode is connected with the green light emitting structure and the blue light emitting structure, and is arranged at a distance from the side wall of the green light emitting structure and the blue light emitting structure;

[0039] A fourth electrode is connected with the red light emitting structure and the green light emitting structure, and is arranged at a distance from the side wall of the green light emitting structure and the blue light emitting structure;

[0040] Step S6, depositing an insulating protective layer covering the RGB stacked structure and the exposed surface of the conductive substrate, and exposing the second electrode, the third electrode and the fourth electrode by photolithography and etching;

[0041] Step S7, removing the first temporary carrier board to form a plurality of pixel units.

[0042] Optionally, the step S4.5 specifically includes the following working procedures:

[0043] Step S4.5a, sticking the second temporary substrate on a first adhesive film;

[0044] Step S4.5b, etching along the surface of the second metal mirror to expose the first adhesive film, forming a second cutting path, and separating into a plurality of independent green light emitting structures;

[0045] Step S4.5c, expanding the first adhesive film by an expansion machine to increase the length of the second cutting path, so that the distance between each green light emitting structure reaches a first preset length;

[0046] Step S4.5d, fixing each green light emitting structure to form a rigid connection, so as to avoid that the first adhesive film is too soft to complete the alignment and bonding in the subsequent working procedure:

[0047] The first adhesive is filled in the second cutting path to connect and fix each green light stacked unit;

[0048] Or

[0049] The first adhesive film is stuck on the second temporary carrier board to fix each green light stacked unit.

[0050] Optionally, the step S4.6 specifically comprises the following procedures:

[0051] Step S4.6a, sticking the third temporary substrate on the second adhesive film;

[0052] Step S4.6b, etching along the surface of the third metal mirror to expose the second adhesive film, forming a third cutting path, and separating into a plurality of independent blue light emitting structures;

[0053] Step S4.6c, expanding the second adhesive film by an expander to increase the length of the third cutting path, so that the distance between each blue light emitting structure reaches a second preset length;

[0054] Step S4.6d, fixing each blue light emitting structure to form a rigid connection, so as to avoid the second adhesive film being too soft to complete the alignment and bonding in subsequent processes:

[0055] Filling the second adhesive in the third cutting path to connect and fix each blue light stack unit; or

[0056] Sticking the second adhesive film on the third temporary carrier to fix each blue light stack unit.

[0057] Optionally, the third electrode is stacked on the green light mesa, and the fourth electrode is stacked on the red light mesa.

[0058] Optionally, one side of the sidewall of the red light emitting structure, the green light emitting structure and the blue light emitting structure is bonded on the same vertical line;

[0059] After the step S4 and before the step S5, the method further comprises a step Q1:

[0060] Etching along the blue light mesa on the side of the vertical line to expose part of the third metal mirror, forming a third metal mirror mesa; etching along the third metal mirror mesa to expose part of the second metal mirror, forming a second metal mirror mesa;

[0061] The step S5 specifically comprises a step Q2:

[0062] A second electrode is stacked on the blue light mesa;

[0063] A third electrode covers the third metal mirror mesa and is arranged at a distance from the sidewall of the green light emitting structure and the blue light emitting structure;

[0064] A fourth electrode covers the second metal mirror mesa and is arranged at a distance from the sidewall of the red light emitting structure and the green light emitting structure.

[0065] Optionally, the first electrode is a P-type electrode, the second electrode is an N-type electrode, and the third electrode and the fourth electrode can be P-type electrodes or N-type electrodes.

[0066] Optionally, the projection area of the red light emitting structure in the vertical direction is S1, the projection area of the green light emitting structure in the vertical direction is S2, and the projection area of the blue light emitting structure in the vertical direction is S3, and S1>S2>S3.

[0067] Optionally, the insulating protective layer comprises a transparent insulating layer and a DBR insulating layer, the transparent insulating layer covers the exposed surfaces of the red mesa, the green mesa and the blue mesa, and the DBR insulating layer covers the sidewalls of the RGB stacked structure and the conductive substrate.

[0068] Via the above technical solution, the following effects are achieved:

[0069] 1. The RGB Micro-LED chip provided by the application has the RGB stacked structure, the RGB stacked structure comprises the red light emitting structure, the green light emitting structure and the blue light emitting structure which are stacked in the first direction in sequence and are distributed in a stepped manner, and the red mesa, the green mesa and the blue mesa are exposed, the vertical stacking manner is adopted, the size of each group of RGB Micro-LED chips can be reduced, and the display resolution is improved; the wavelength of each light emitting structure gradually decreases along the light emitting direction, and the metal reflector is arranged, so that each emitted light is emitted along the light emitting direction, the emitted light of the short-wavelength light emitting structure is prevented from being absorbed by the long-wavelength light emitting structure, and the light emitting efficiency of the RGB Micro-LED chip is improved.

[0070] 2. Further, the third electrode covers the third metal reflector mesa, and the fourth electrode covers the second metal reflector mesa, so that the conductive efficiency of the third electrode and the fourth electrode can be further improved, and the light emitting efficiency of the RGB Micro-LED chip is improved.

[0071] 3. Further, the first electrode is a P-type electrode, the second electrode is an N-type electrode, and the third electrode and the fourth electrode can be P-type electrodes or N-type electrodes, so that the red, green and blue single color control and the color mixing control can be realized by controlling the first electrode, the second electrode, the third electrode and the fourth electrode according to actual needs.

[0072] 4、Further, by setting the insulating protective layer including the transparent insulating layer and the DBR insulating layer, the transparent insulating layer covers the exposed surfaces of the red light mesa, the green light mesa and the blue light mesa, and the DBR insulating layer covers the sidewalls of the RGB stacked structure and the conductive substrate, so that the reliability can be realized, and the light emitted by the sidewalls of each light emitting structure can be reflected, so that the red light emission is concentrated on the red light mesa, the green light emission is concentrated on the green light mesa, and the blue light emission is concentrated on the blue light mesa, thereby further improving the display resolution.

[0073] 5、The manufacturing method of the RGB Micro-LED chip provided by the embodiment is used for preparing the RGB Micro-LED chip, the red light stacked structure, the green light stacked structure and the blue light stacked structure are formed on different temporary substrates, then separated into a plurality of independent red light emitting structures, green light emitting structures and blue light emitting structures, then the RGB stacked structure is formed by alignment bonding, and then a plurality of pixel units are formed by combining the conductive substrate, the electrodes and the insulating protective layer, and then the RGB Micro-LED chip is combined, so that the problems of great difficulty in mass transfer, low yield in mass production, high production cost, poor consistency and the like caused by the too complex manufacturing process can be effectively solved. BRIEF DESCRIPTION OF DRAWINGS

[0074] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the provided drawings.

[0075] Figure 1 A cross-sectional schematic view of an RGB Micro-LED chip provided by an embodiment of the present application;

[0076] Figure 2 A cross-sectional schematic view of another RGB Micro-LED chip provided by an embodiment of the present application;

[0077] Figure 3 A cross-sectional schematic view of another RGB Micro-LED chip provided by an embodiment of the present application;

[0078] Figure 4 A cross-sectional schematic view of another RGB Micro-LED chip provided by an embodiment of the present application;

[0079] Figures 5.1 to 19 A process cross-sectional view corresponding to each step of a manufacturing method of an RGB Micro-LED chip provided by an embodiment of the present application;

[0080] Figures 20 to 24Another RGB Micro-LED chip manufacturing method provided by the embodiment of the present application corresponds to the process cross-sectional view of each step.

[0081] Explanation of symbols in the figure:

[0082] 1, pixel unit; 10a, first temporary substrate; 10b, second temporary substrate; 10c, third temporary substrate; 20, red light stack structure; 30, green light stack structure; 40, blue light stack structure; 50a, first temporary carrier plate; 50b, second temporary carrier plate; 50c, third temporary carrier plate; 60a, first cutting path; 60b, second cutting path; 60c, third cutting path; 70a, first adhesive film; 70b, second adhesive film; 80a, first adhesive; 80b, second adhesive; 100, conductive substrate; 200, red light emitting structure; 210, red light N-type semiconductor layer; 220, red light active region; 230, red light P-type semiconductor layer; 240, first metal mirror; 300, green light emitting structure; 310, green light N-type semiconductor layer; 320, green light active region; 330, green light P-type semiconductor layer; 340, second metal mirror; 400, blue light emitting structure; 410, blue light N-type semiconductor layer; 420, blue light active region; 430, blue light P-type semiconductor layer; 440, third metal mirror; 510, first electrode; 520, second electrode; 530, third electrode; 540, fourth electrode; 600, insulating protective layer; 610, transparent insulating layer; 620, DBR insulating layer; T1, red light mesa; T2, green light mesa; T3, blue light mesa; S1, projection area of the red light emitting structure in the vertical direction; S2, projection area of the green light emitting structure in the vertical direction; S3, projection area of the blue light emitting structure in the vertical direction. DETAILED DESCRIPTION

[0083] In order to make the content of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0084] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be practiced in a variety of ways beyond the specific embodiments described herein, and the skilled in the art can make similar modifications without departing from the spirit of the present application, so the present application is not limited to the specific embodiments disclosed below.

[0085] Secondly, the application is described in detail in combination with the schematic diagram. In the detailed description of the embodiments of the application, the cross-sectional view of the device structure is locally enlarged without the general proportion for the convenience of description, and the schematic diagram is only an example, which should not limit the scope of protection of the application here. In addition, the three-dimensional spatial dimensions including length, width and depth should be included in actual manufacturing.

[0086] The RGB Micro-LED chip provided by the embodiment of the application comprises: Figure 1

[0087] The pixel units 1 each comprise:

[0088] The conductive substrate 100;

[0089] The RGB stack structure stacked on the surface of the conductive substrate 100, the RGB stack structure comprising red light emitting structures 200, green light emitting structures 300 and blue light emitting structures 400 stacked in the first direction in turn and distributed in a stepped manner, and exposing red light terraces T1, green light terraces T2 and blue light terraces T3, the red light emitting structures 200 comprising a first metal mirror 240, a red light P-type semiconductor layer 230, a red light active region 220 and a red light N-type semiconductor layer 210 stacked in the first direction in turn; the green light emitting structures 300 comprising a second metal mirror 340, a green light P-type semiconductor layer 330, a green light active region 320 and a green light N-type semiconductor layer 310 stacked in the first direction in turn; the blue light emitting structures 400 comprising a third metal mirror 440, a blue light P-type semiconductor layer 430, a blue light active region 420 and a blue light N-type semiconductor layer 410 stacked in the first direction in turn, the first direction being perpendicular to the conductive substrate 100 and pointing to the blue light emitting structures 400 from the conductive substrate 100;

[0090] The red light emitting structures 200, the green light emitting structures 300 and the blue light emitting structures 400 are connected in series by the metal mirrors in pairs;

[0091] The specific material of the first metal mirror 240, the second metal mirror 340 and the third metal mirror 440 is not limited in the embodiment, and optionally, the material of the first metal mirror 240, the second metal mirror 340 and the third metal mirror 440 comprises one or more of Ag, Al, Au, Cu and other metal materials in the embodiment.

[0092] The material of the first metal mirror 240, the second metal mirror 340 and the third metal mirror 440 can be the same or different in the embodiment.

[0093] The first electrode 510 is arranged on the side surface of the conductive substrate 100 away from the RGB stack structure;

[0094] ​a second electrode 520 stacked on the blue mesa T3;

[0095] a third electrode 530 connected with the green light emitting structure 300 and the blue light emitting structure 400 and arranged at a distance from the sidewalls of the green light emitting structure 300 and the blue light emitting structure 400;

[0096] a fourth electrode 540 connected with the red light emitting structure 200 and the green light emitting structure 300 and arranged at a distance from the sidewalls of the red light emitting structure 200 and the green light emitting structure 300;

[0097] Optionally, in the embodiment, the third electrode 530 is stacked on the green mesa T2, and the fourth electrode 540 is stacked on the red mesa T1.

[0098] an insulating protective layer 600 covering the RGB stacked structure and the exposed surface of the conductive substrate 100 and exposing the second electrode 520, the third electrode 530 and the fourth electrode 540.

[0099] Optionally, in the embodiment, the projection area of the red light emitting structure in the vertical direction is S1, the projection area of the green light emitting structure in the vertical direction is S2, and the projection area of the blue light emitting structure in the vertical direction is S3, then S1>S2>S3.

[0100] Optionally, in the embodiment, the red mesa T1 and the green mesa T2 are both annular mesas.

[0101] Optionally, in the embodiment, the first electrode 510 is a P-type electrode, the second electrode 520 is an N-type electrode, and the third electrode 530 and the fourth electrode 540 can be P-type electrodes or N-type electrodes. According to actual needs, red, green and blue single color control and color mixing control can be realized by controlling the first electrode, the second electrode, the third electrode and the fourth electrode.

[0102] It should be noted that, Figures 1 to 4 Both show two pixel units 1, and those skilled in the art should understand that the figure is only schematic, and the pixel unit 1 of the present application is not limited to two.

[0103] The RGB Micro-LED chip provided in the embodiment is provided with an RGB stacking structure, the RGB stacking structure comprises red light emitting structures, green light emitting structures and blue light emitting structures which are sequentially stacked in a stepped manner along a first direction and expose red light platforms, green light platforms and blue light platforms, and the vertical stacking manner can reduce the size of each group of RGB Micro-LED chips and improve the display resolution; and the wavelengths of the light emitting structures gradually decrease along the light emitting direction, and the setting of the metal reflectors makes the emitted light emit along the light emitting direction, avoiding the emitted light of the short-wavelength light emitting structure being absorbed by the long-wavelength light emitting structure, thereby improving the light emitting efficiency of the RGB Micro-LED chip.

[0104] To improve the conductivity of the third electrode and the fourth electrode, optionally, in an embodiment of the present application, as shown in Figure 2 , the blue light platform T3 is provided with a groove extending towards the third metal reflector 440, exposing part of the third metal reflector 440 to form a third metal reflector platform; the third metal reflector platform is provided with a groove extending towards the second metal reflector 340, exposing part of the second metal reflector 340 to form a second metal reflector platform; the third electrode 530 covers the third metal reflector platform, and the fourth electrode 540 covers the second metal reflector platform.

[0105] To further improve the display resolution, optionally, in an embodiment of the present application, as shown in Figure 3 or Figure 4 , the insulating protective layer 600 comprises a transparent insulating layer 610 and a DBR insulating layer 620, the transparent insulating layer 610 covers the exposed surfaces of the red light platform T1, the green light platform T2 and the blue light platform T3, and the DBR insulating layer 620 covers the side walls of the RGB stacking structure and the conductive substrate 100. That is, reliability can be achieved, and the light emitted by the side walls of the light emitting structures can be reflected, so that the red light emission is concentrated on the red light platform, the green light emission is concentrated on the green light platform, and the blue light emission is concentrated on the blue light platform.

[0106] The present application also provides a manufacturing method of the RGB Micro-LED chip, and the manufacturing method comprises the following steps:

[0107] Step S1, as shown in Figures 5.1 to 5.3 , the red light stacking structure 20 is formed on the first temporary substrate 10a by epitaxy, the green light stacking structure 30 is formed on the second temporary substrate 10b by epitaxy, and the blue light stacking structure 40 is formed on the third temporary substrate 10c by epitaxy;

[0108] The red light stacking structure 20 comprises a red light N-type semiconductor layer 210, a red light active region 220, a red light P-type semiconductor layer 230 and a first metal reflector 240 which are stacked in sequence along the growth direction;

[0109] The green light stack structure 30 comprises, in sequence along a growth direction, a green light N-type semiconductor layer 310, a green light active region 320, a green light P-type semiconductor layer 330 and a second metal mirror 340 which are stacked;

[0110] The blue light stack structure 40 comprises, in sequence along a growth direction, a blue light N-type semiconductor layer 410, a blue light active region 420, a blue light P-type semiconductor layer 430 and a third metal mirror 440 which are stacked;

[0111] In the embodiment, the specific material of the first temporary substrate 10a, the second temporary substrate 10b and the third temporary substrate 10c is not limited, and in the embodiment, the first temporary substrate 10a can be a semiconductor substrate such as a GaAs substrate, and the second temporary substrate 10b and the third temporary substrate 10c can be a semiconductor substrate such as a sapphire substrate, a silicon substrate, a silicon carbide substrate or a gallium nitride substrate, and the specific material of the temporary substrate can be selected and used according to requirements.

[0112] Optionally, in the embodiment, the first temporary substrate is larger than the second temporary substrate, and the second temporary substrate is larger than the third temporary substrate.

[0113] Step S2, providing a conductive substrate 100;

[0114] Step S3, as shown in the drawing, a first electrode 510 is made on one side surface of the conductive substrate 100; Figure 6

[0115] Step S4, forming an RGB stack structure on the side surface of the conductive substrate 100 away from the first electrode 510, the RGB stack structure comprises red light emitting structures 200, green light emitting structures 300 and blue light emitting structures 400 which are stacked in sequence along a first direction and are distributed in a stepped manner, and red light terraces T1, green light terraces T2 and blue light terraces T3 are exposed; the red light emitting structures 200 comprise, in sequence along the first direction, a first metal mirror 240, a red light P-type semiconductor layer 230, a red light active region 220 and a red light N-type semiconductor layer 210 which are stacked; the green light emitting structures 300 comprise, in sequence along the first direction, a second metal mirror 340, a green light P-type semiconductor layer 330, a green light active region 320 and a green light N-type semiconductor layer 310 which are stacked; the blue light emitting structures 400 comprise, in sequence along the first direction, a third metal mirror 440, a blue light P-type semiconductor layer 430, a blue light active region 420 and a blue light N-type semiconductor layer 410 which are stacked, the first direction is perpendicular to the conductive substrate 100, and the conductive substrate 100 points to the blue light emitting structures 400;

[0116] The red light emitting structures 200, the green light emitting structures 300 and the blue light emitting structures 400 are connected in series through the metal mirrors;

[0117] ​In this embodiment, the specific materials of the first metal reflector 240, the second metal reflector 340, and the third metal reflector 440 are not limited. Optionally, in this embodiment, the materials of the first metal reflector 240, the second metal reflector 340, and the third metal reflector 440 include one or more metal materials such as Ag, Al, Au, and Cu.

[0118] In this embodiment, the materials of the first metal reflector 240, the second metal reflector 340, and the third metal reflector 440 can be the same or different.

[0119] Step S4 specifically includes the following procedures:

[0120] Step S4.1, as follows Figure 7 As shown, the red light stacked structure 20 is bonded to the conductive substrate 100 through the first metal reflector 240;

[0121] Step S4.2, as follows Figure 8 As shown, the first temporary substrate 10a is stripped off;

[0122] Step S4.3, as follows Figure 9 As shown, the first electrode 510 is attached to the first temporary carrier plate 50a using adhesive.

[0123] Step S4.4, as follows Figure 10 As shown, etching is performed along the surface of the red light N-type semiconductor layer 210 to expose the first temporary carrier 50a, forming the first dicing channel 60a, which separates the red light stacked structure 20 into multiple independent red light emitting structures 200.

[0124] Step S4.5: By etching and film expansion, the green light stacking structure 30 is separated into multiple independent green light emitting structures 300, and the distance between each green light emitting structure 300 reaches a first preset length.

[0125] Step S4.5 specifically includes the following procedures:

[0126] Step S4.5a, as follows Figure 11.1 As shown, the second temporary substrate 10b is adhered to the first adhesive film 70a;

[0127] Step S4.5b, as follows Figure 11.2 As shown, etching is performed along the surface of the second metal mirror 340 to expose the first adhesive film 70a, forming the second cutting channel 60b, which separates into multiple independent green light-emitting structures 300.

[0128] Step S4.5c, as follows Figure 11.3As shown, the first adhesive film 70a is expanded by a film expander to increase the length of the second cutting channel 60b, so that the distance between each green light emitting structure 300 reaches the first preset length.

[0129] Step S4.5d: Fix each green light-emitting structure 300 to form a rigid connection, to prevent the first adhesive film 70a from being too soft and causing subsequent processes to fail to complete the alignment and bonding:

[0130] like Figure 11.4a As shown, the first adhesive 80a is filled into the second cutting channel 60b to connect and fix each green light-emitting structure 300.

[0131] or

[0132] like Figure 11.4b As shown, the first adhesive film 70a is adhered to the second temporary carrier plate 50b to fix each green light emitting structure 300.

[0133] Step S4.6: By etching and film expansion, the blue light stacking structure 40 is separated into multiple independent blue light emitting structures 400, and the distance between each blue light emitting structure 400 reaches the second preset length.

[0134] Step S4.6 specifically includes the following processes:

[0135] Step S4.6a, as Figure 12.1 As shown, the third temporary substrate 10c is adhered to the second adhesive film 70b;

[0136] Step S4.6b, as follows Figure 12.2 As shown, etching is performed along the surface of the third metal mirror 440 to expose the second adhesive film 70b, forming the third cutting channel 60c, which separates into multiple independent blue light emitting structures 400.

[0137] Step S4.6c, as follows Figure 12.3 As shown, the second adhesive film 70b is expanded by a film expander to increase the length of the third cutting channel 60c, so that the distance between each blue light-emitting structure reaches the second preset length.

[0138] Step S4.6d: Fix each blue light-emitting structure 400 to form a rigid connection, to prevent the second adhesive film 70b from being too soft and causing subsequent processes to fail to complete the alignment and bonding:

[0139] like Figure 12.4a As shown, a second adhesive 80b is filled in the third cutting channel 60c to connect and fix each blue light emitting structure 400.

[0140] or

[0141] like Figure 12.4bAs shown, the second adhesive film 70b is adhered to the third temporary carrier plate 50c to fix each blue light emitting structure 400.

[0142] In this embodiment, the specific materials of the first adhesive film 70a and the second adhesive film 70b are not limited. Optionally, in this embodiment, the first adhesive film 70a and the second adhesive film 70b are thin film materials with adhesive properties, including one or more of materials such as polyimide and heat-sensitive DAF film.

[0143] In this embodiment, the specific materials of the first adhesive 80a and the second adhesive 80b are not limited. Optionally, in this embodiment, the materials of the first adhesive 80a and the second adhesive 80b include one or more of the following: acrylate, epoxy resin, polyurethane, polystyrene, polyacrylate, ethylene-vinyl acetate copolymer, etc.

[0144] In this embodiment, the specific materials of the first temporary carrier 50a, the second temporary carrier 50b, and the third temporary carrier 50c are not limited. Optionally, in this embodiment, the materials of the first temporary carrier 50a, the second temporary carrier 50b, and the third temporary carrier 50c include one of the following materials: Si substrate, sapphire substrate, etc.

[0145] Step S4.7: Using the second metal reflector 340 and the red N-type semiconductor layer 210, each green light emitting structure 300 is aligned and bonded to each red light emitting structure 200, exposing the red light mesa T1, and the second temporary substrate 10b is peeled off.

[0146] against Figure 11.4a The resulting structure, step S4.7 specifically includes the following processes:

[0147] like Figure 13.1 As shown, each green light emitting structure 300 is aligned and bonded to each red light emitting structure 200 through the second metal reflector 340 and the red light N-type semiconductor layer 210, exposing the red light mesa T1.

[0148] like Figure 13.2 As shown, the first adhesive film 70a and part of the first adhesive 80a are removed so that the first adhesive 80a is flush with the green N-type semiconductor layer 310; the second temporary substrate 10b is removed by laser; the first adhesive film 70a and part of the first adhesive 80a can be removed simultaneously by an etching solution; or the first adhesive film 70a can be peeled off first, and then part of the first adhesive 80a can be removed by an etching solution.

[0149] or

[0150] against Figure 11.4b The resulting structure, step S4.7 specifically includes the following processes:

[0151] likeFigure 14.1 As shown, each green light emitting structure 300 is aligned and bonded on each red light emitting structure 200 through the second metal mirror 340 and the red light N-type semiconductor layer 210 respectively, and the red light mesa T1 is exposed;

[0152] As shown, Figure 14.2 The etching solution removes the first adhesive film 70a, and the second temporary carrier 50b is automatically separated; the second temporary substrate 10b is laser stripped;

[0153] Step S4.8, each blue light emitting structure 400 is aligned and bonded on each green light emitting structure 300 through the third metal mirror 440 and the green light N-type semiconductor layer 310 respectively, the green light mesa T2 is exposed, and the third temporary substrate 10c is stripped, and the blue light mesa T3 is exposed;

[0154] For the structure formed as shown in Figure 12.4a and Figure 13.2 Step S4.8 specifically includes the following procedures:

[0155] As shown, Figure 15.1 Each blue light emitting structure 400 is aligned and bonded on each green light emitting structure 300 through the third metal mirror 440 and the green light N-type semiconductor layer 310 respectively, the green light mesa T2 is exposed,

[0156] As shown, Figure 15.2 The second adhesive film 70b, the first adhesive 80a and the second adhesive 80b are removed; the third temporary substrate 10c is laser stripped, and the blue light mesa T3 is exposed; the second adhesive film 70b, the first adhesive 80a and the second adhesive 80b can also be removed at the same time by using an etching solution; or the second adhesive film 70b can be torn off first, and then the first adhesive 80a and the second adhesive 80b are removed by using an etching solution.

[0157] Or

[0158] For the structure formed as shown in Figure 12.4b and Figure 14.2 Step S4.8 specifically includes the following procedures:

[0159] As shown, Figure 16.1 Each blue light emitting structure 400 is aligned and bonded on each green light emitting structure 300 through the third metal mirror 440 and the green light N-type semiconductor layer 310 respectively, the green light mesa T2 is exposed,

[0160] As shown, Figure 16.2 The second adhesive film 70b is etched and removed, and the third temporary carrier 50c is automatically separated; the third temporary substrate 10c is laser stripped, and the blue light mesa T3 is exposed;

[0161] It should be noted that this embodiment does not limit the specific location of the alignment bonding. As long as the red light-emitting structure 200, green light-emitting structure 300, and blue light-emitting structure 400 are stacked sequentially along the first direction and distributed in a stepped manner, exposing the red light mesa T1, green light mesa T2, and blue light mesa T3, the specific bonding location can be selected according to actual needs. Optionally, in this embodiment, the center lines of the red light-emitting structure 200, green light-emitting structure 300, and blue light-emitting structure 400 are bonded on the same vertical line.

[0162] Step S5, as follows Figure 17 As shown, the second electrode 520, the third electrode 530, and the fourth electrode 540 are fabricated.

[0163] The second electrode 520 is stacked on the blue light platform T3;

[0164] The third electrode 530 is connected to the green light emitting structure 300 and the blue light emitting structure 400, and is positioned at a distance from the sidewalls of the green light emitting structure 300 and the blue light emitting structure 400.

[0165] The fourth electrode 540 is connected to the red light emitting structure 200 and the green light emitting structure 300, and is set at a distance from the sidewalls of the red light emitting structure 200 and the green light emitting structure 300.

[0166] Optionally, in this embodiment, the third electrode 530 is stacked on the green light platform T2, and the fourth electrode 540 is stacked on the red light platform T1.

[0167] Step S6, as follows Figure 18 As shown, an insulating protective layer 600 is deposited, which covers the exposed surfaces of the RGB stacked structure and the conductive substrate 100, and exposes the second electrode 520, the third electrode 530 and the fourth electrode 540 through photolithography and etching.

[0168] Step S7, as follows Figure 19 As shown, the first temporary carrier plate 50a is removed to form several pixel units 1.

[0169] Optionally, in this embodiment, the projected area of ​​the red light emitting structure in the vertical direction is S1, the projected area of ​​the green light emitting structure in the vertical direction is S2, and the projected area of ​​the blue light emitting structure in the vertical direction is S3, then S1 > S2 > S3.

[0170] Optionally, in this embodiment, both the red light platform T1 and the green light platform T2 are annular platforms.

[0171] Optionally, in the embodiment, the first electrode 510 is a P-type electrode, the second electrode 520 is an N-type electrode, and the third electrode 530 and the fourth electrode 540 can be P-type electrodes or N-type electrodes. According to actual needs, by controlling the first electrode, the second electrode, the third electrode, and the fourth electrode, red, green, and blue three primary color single color control and color mixing control can be realized.

[0172] The embodiment provides a manufacturing method of an RGB Micro-LED chip. Through the manufacturing method, the RGB stacked structure is formed, the RGB stacked structure comprises red light emitting structures, green light emitting structures, and blue light emitting structures which are sequentially stacked in a first direction and are distributed in a stepped manner, and red light platforms, green light platforms, and blue light platforms are exposed. The RGB Micro-LED chip is manufactured in a vertical stacking manner, so that the size of each group of RGB Micro-LED chips can be reduced, and the display resolution is improved. The wavelengths of the light emitting structures gradually decrease along the light emitting direction, and the metal reflector is arranged, so that the emitted light of each light emitting structure is emitted along the light emitting direction, the emitted light of the short-wavelength light emitting structure is prevented from being absorbed by the long-wavelength light emitting structure, and the light emitting efficiency of the RGB Micro-LED chip is improved.

[0173] Furthermore, the red light stacked structure, the green light stacked structure, and the blue light stacked structure are formed on different temporary substrates, and then are separated into a plurality of independent red light emitting structures, green light emitting structures, and blue light emitting structures. Then, the RGB stacked structure is formed by alignment bonding, and a plurality of pixel units are formed by combining the conductive substrate, the electrodes, and the insulating protective layer, and then the RGB Micro-LED chip is combined, so that the problems of great difficulty in mass transfer, low yield in mass production, high production cost, poor consistency, and the like caused by the too complex manufacturing process can be effectively solved.

[0174] To further improve the display resolution, in an embodiment of the present application, as shown in Figure 3 , the insulating protective layer 600 comprises a transparent insulating layer 610 and a DBR insulating layer 620. The transparent insulating layer 610 covers the exposed surfaces of the red light platform T1, the green light platform T2, and the blue light platform T3. The DBR insulating layer 620 covers the side walls of the RGB stacked structure and the conductive substrate 100. The reliability can be realized, and the light emitted by the side walls of the light emitting structures can be reflected, so that the red light is emitted and concentrated on the red light platform, the green light is emitted and concentrated on the green light platform, and the blue light is emitted and concentrated on the blue light platform.

[0175] The present application also provides another manufacturing method of an RGB Micro-LED chip, which is different from the above manufacturing method, as shown in Figure 20 , one side wall of the red light emitting structure 200, the green light emitting structure 300, and the blue light emitting structure 400 is bonded on the same vertical line;

[0176] After step S4 and before step S5, step Q1 is further included.

[0177] As shown in FIG. 6, the blue light mesa T3 on the vertical line is etched to expose part of the third metal mirror 440 to form a third metal mirror mesa; and the third metal mirror mesa is etched to expose part of the second metal mirror 340 to form a second metal mirror mesa. Figure 21

[0178] As shown in FIG. 7, step S5 specifically includes step Q2. Figure 22

[0179] The second electrode 520 is laminated on the blue light mesa T3.

[0180] The third electrode 530 covers the third metal mirror mesa and is arranged at a distance from the sidewalls of the green light emitting structure 300 and the blue light emitting structure 400.

[0181] The fourth electrode 540 covers the second metal mirror mesa and is arranged at a distance from the sidewalls of the red light emitting structure 200 and the green light emitting structure 300.

[0182] As shown in FIG. 8, step S6 specifically includes step Q3. Figure 23

[0183] As shown in FIG. 9, step S7 specifically includes step Q4. Figure 24

[0184] The manufacturing method of the RGB Micro-LED chip provided in the embodiment can further improve the conductive efficiency of the third electrode and the fourth electrode, and further improve the light emitting efficiency of the RGB Micro-LED chip.

[0185] To further improve the display resolution, in an embodiment of the present application, the insulating protective layer 600 includes a transparent insulating layer 610 and a DBR insulating layer 620, the transparent insulating layer 610 covers the exposed surfaces of the red light mesa T1, the green light mesa T2 and the blue light mesa T3, and the DBR insulating layer 620 covers the sidewalls of the RGB stacked structure and the conductive substrate 100. Figure 4 ​​​​​

[0186] Those skilled in the art will understand that the terms "lateral", "longitudinal", "upper", "lower" and the like designate orientation or positional relationships in the disclosure of the present application, which are based on the orientation or positional relationships shown in the drawings, and are merely for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore the above terms cannot be understood as a limitation on the present application.

[0187] It should be noted that each of the embodiments in the present specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same or similar parts between the embodiments can be mutually referred to.

[0188] The above description of the disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to the embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An RGB Micro-LED chip, characterized in that, include: A plurality of pixel units, each of the pixel units comprising: Conductive substrate; An RGB stacked structure is layered on the surface of a conductive substrate. The RGB stacked structure includes red light-emitting structures, green light-emitting structures, and blue light-emitting structures stacked sequentially along a first direction and arranged in a stepped manner, such that the wavelength of each light-emitting structure gradually decreases along the light emission direction, exposing red light mesa, green light mesa, and blue light mesa. The red light-emitting structure includes, along the first direction, a first metal reflector, a red P-type semiconductor layer, a red active region, and a red N-type semiconductor layer stacked sequentially. The green light-emitting structure includes, along the first direction, a second metal reflector, a green P-type semiconductor layer, a green active region, and a green N-type semiconductor layer stacked sequentially. The blue light-emitting structure includes, along the first direction, a third metal reflector, a blue P-type semiconductor layer, a blue active region, and a blue N-type semiconductor layer stacked sequentially. The first direction is perpendicular to the conductive substrate and extends from the conductive substrate towards the blue light-emitting structure. The red light emitting structure, the green light emitting structure, and the blue light emitting structure are connected in series in pairs via metal mirrors; The blue light platform has a groove extending toward the third metal mirror, exposing part of the third metal mirror to form a third metal mirror platform; the third metal mirror platform has a groove extending toward the second metal mirror, exposing part of the second metal mirror to form a second metal mirror platform. The first electrode is disposed on the surface of the conductive substrate opposite to the RGB stacked structure. The second electrode is stacked on the blue light platform; The third electrode covers the third metal reflector platform, is connected to the green light emitting structure and the blue light emitting structure, and is positioned at a distance from the sidewalls of the green light emitting structure and the blue light emitting structure; The fourth electrode covers the stage of the second metal reflector, is connected to the red light emitting structure and the green light emitting structure, and is positioned at a distance from the sidewalls of the red light emitting structure and the green light emitting structure. An insulating protective layer covers the exposed surfaces of the RGB stacked structure and the conductive substrate, and exposes the second electrode, the third electrode, and the fourth electrode.

2. The RGB Micro-LED chip according to claim 1, characterized in that: The first electrode is a P-type electrode, the second electrode is an N-type electrode, and the third and fourth electrodes are either P-type or N-type electrodes.

3. The RGB Micro-LED chip according to claim 1, characterized in that: If the projected area of ​​the red light-emitting structure in the vertical direction is S1, the projected area of ​​the green light-emitting structure in the vertical direction is S2, and the projected area of ​​the blue light-emitting structure in the vertical direction is S3, then S1 > S2 > S3.

4. The RGB Micro-LED chip according to claim 1, characterized in that: The insulating protective layer includes a transparent insulating layer and a DBR insulating layer. The transparent insulating layer covers the exposed surfaces of the red light platform, the green light platform, and the blue light platform, and the DBR insulating layer covers the sidewalls of the RGB stacked structure and the conductive substrate.

5. A method for fabricating an RGB Micro-LED chip, characterized in that, Includes the following steps: Step S1: A red light stacked structure is epitaxially formed on a first temporary substrate, a green light stacked structure is epitaxially formed on a second temporary substrate, and a blue light stacked structure is epitaxially formed on a third temporary substrate. Step S2: Provide a conductive substrate; Step S3: Form a first electrode on one side surface of the conductive substrate; Step S4: An RGB stacked structure is formed on the surface of the conductive substrate away from the first electrode. The RGB stacked structure includes red light-emitting structures, green light-emitting structures, and blue light-emitting structures stacked sequentially along a first direction and arranged in a stepped manner, so that the wavelength of each light-emitting structure gradually decreases along the light emission direction, and exposes the red light mesa, green light mesa, and blue light mesa. The red light-emitting structure includes, along the first direction, a first metal reflector, a red P-type semiconductor layer, a red active region, and a red N-type semiconductor layer stacked sequentially. The green light-emitting structure includes, along the first direction, a second metal reflector, a green P-type semiconductor layer, a green active region, and a green N-type semiconductor layer stacked sequentially. The blue light-emitting structure includes, along the first direction, a third metal reflector, a blue P-type semiconductor layer, a blue active region, and a blue N-type semiconductor layer stacked sequentially. The first direction is perpendicular to the conductive substrate and points from the conductive substrate to the blue light-emitting structure. The red light emitting structure, the green light emitting structure, and the blue light emitting structure are connected in series in pairs via metal mirrors; Step S4 specifically includes the following procedures: Step S4.1: Bond the red light stacked structure onto the conductive substrate using the first metal reflector; Step S4.2: Remove the first temporary substrate; Step S4.3: Adhere the first electrode to the first temporary carrier plate using adhesive. Step S4.4: Etch along the surface of the red N-type semiconductor layer to expose the first temporary carrier, forming a first dicing path, and separating the red stacked structure into multiple independent red light emitting structures; Step S4.5: By etching and film expansion, the green light stacking structure is separated into multiple independent green light emitting structures, and the distance between each green light emitting structure reaches a first preset length. Step S4.6: By etching and film expansion, the blue light stacking structure is separated into multiple independent blue light emitting structures, and the distance between each blue light emitting structure reaches a second preset length; Step S4.7: Using the second metal mirror and the red N-type semiconductor layer, each of the green light emitting structures is aligned and bonded to each of the red light emitting structures to expose the red light mesa, and the second temporary substrate is peeled off. Step S4.8: Using the third metal mirror and the green N-type semiconductor layer, each blue light emitting structure is aligned and bonded to each green light emitting structure to expose the green light mesa, and the third temporary substrate is peeled off to expose the blue light mesa. In this configuration, one sidewall of each of the red light-emitting structure, the green light-emitting structure, and the blue light-emitting structure is bonded to the same vertical line. Step Q1: Etch along the blue light platform on the side of the vertical line to expose part of the third metal mirror, forming the third metal mirror platform; etch along the third metal mirror platform to expose part of the second metal mirror, forming the second metal mirror platform; Step S5: Fabricate the second, third, and fourth electrodes; Step S5 specifically includes step Q2: The second electrode is stacked on the blue light platform; The third electrode covers the third metal reflector platform, is connected to the green light emitting structure and the blue light emitting structure, and is positioned at a distance from the sidewalls of the green light emitting structure and the blue light emitting structure; The fourth electrode covers the stage of the second metal reflector, is connected to the red light emitting structure and the green light emitting structure, and is positioned at a distance from the sidewalls of the green light emitting structure and the blue light emitting structure. Step S6: Deposit an insulating protective layer, which covers the exposed surfaces of the RGB stacked structure and the conductive substrate, and exposes the second electrode, the third electrode and the fourth electrode through photolithography and etching; Step S7: Remove the first temporary carrier plate to form several pixel units.

6. The method for manufacturing an RGB Micro-LED chip according to claim 5, characterized in that: Step S4.5 specifically includes the following procedures: Step S4.5a: Adhere the second temporary substrate to the first adhesive film; Step S4.5b: Etch along the surface of the second metal mirror to expose the first adhesive film, forming a second cutting channel, separating it into multiple independent green light-emitting structures; Step S4.5c: Expand the first adhesive film using a film expansion machine to increase the length of the second cutting channel, so that the distance between each of the green light emitting structures reaches the first preset length; Step S4.5d: Fix each of the green light-emitting structures to form a rigid connection to prevent the first adhesive film from being too soft and causing subsequent processes to fail to complete the alignment and bonding. The first adhesive is filled into the second cutting channel to connect and fix each of the green light stacking units; or The first adhesive film is adhered to the second temporary carrier plate to fix each of the green light stacking units.

7. The method for manufacturing an RGB Micro-LED chip according to claim 5, characterized in that: Step S4.6 specifically includes the following procedures: Step S4.6a: Adhere the third temporary substrate to the second adhesive film; Step S4.6b: Etch along the surface of the third metal mirror to expose the second adhesive film, forming a third cutting channel, separating it into multiple independent blue light emitting structures; Step S4.6c: Expand the second adhesive film using a film expansion machine to increase the length of the third cutting channel, so that the distance between each blue light emitting structure reaches the second preset length; Step S4.6d: Fix each of the blue light-emitting structures to form a rigid connection to prevent the second adhesive film from being too soft and causing subsequent processes to fail to complete the alignment and bonding. A second adhesive is filled into the third cutting channel to connect and fix each of the blue light stacking units; or The second adhesive film is adhered to the third temporary carrier plate to fix each of the blue light stacking units.

8. The method for manufacturing an RGB Micro-LED chip according to claim 5, characterized in that: The first electrode is a P-type electrode, the second electrode is an N-type electrode, and the third and fourth electrodes are either P-type or N-type electrodes.

9. The method for manufacturing an RGB Micro-LED chip according to claim 5, characterized in that: If the projected area of ​​the red light-emitting structure in the vertical direction is S1, the projected area of ​​the green light-emitting structure in the vertical direction is S2, and the projected area of ​​the blue light-emitting structure in the vertical direction is S3, then S1 > S2 > S3.

10. The method for manufacturing an RGB Micro-LED chip according to claim 5, characterized in that: The insulating protective layer includes a transparent insulating layer and a DBR insulating layer. The transparent insulating layer covers the exposed surfaces of the red light platform, the green light platform, and the blue light platform, and the DBR insulating layer covers the sidewalls of the RGB stacked structure and the conductive substrate.

Images