Red light micro-led and manufacturing method thereof

Abstract

This invention discloses a red-light Micro-LED and its fabrication method. The red-light Micro-LED includes: a substrate (10); an AlGaInP barrier layer disposed on the substrate (10); and an InP quantum dot hydrazine layer (14) stacked on the AlGaInP barrier layer. Compared with the traditional device structure based on AlGaInP quantum wells, the InP quantum dot well layer proposed in this invention can confine charge carriers within the InP quantum dots to emit light, thereby suppressing the lateral diffusion of charge carriers and effectively suppressing sidewall recombination in the Micro-LED, thus improving the luminous efficiency of the Micro-LED.

Description

Technical Field

[0001] This invention belongs to the field of optoelectronics and semiconductor technology, specifically relating to a red Micro-LED and its manufacturing method. Background Technology

[0002] Micro-LED displays utilize micron-sized inorganic LED devices as light-emitting pixels to achieve active-matrix display, and are considered a disruptive next-generation display technology. For full-color Micro-LEDs, blue and green Micro-LEDs based on the InGaN material system have already achieved high quantum efficiencies, supporting product-level applications. However, for red Micro-LEDs, traditional large-size (above 50μm) red LEDs based on AlGaInP quantum hydrazine can achieve an external quantum efficiency of around 50%, but as the chip size decreases (below 50μm), the luminous efficiency of small-size chips drops rapidly.

[0003] Currently, the external quantum efficiency of existing small-sized AlInGaP quantum hydrazine-based red micro-LEDs is only around 1-3%, mainly due to the high surface recombination rate of AlInGaP materials and the excessively long electron-hole pair diffusion length. Figure 1 As shown, when a Micro-LED operates, electrons and holes are injected into the active region (GaInP) of the AlInGaP quantum hydrazine. Due to the long radiative recombination lifetime, the lateral diffusion length of electron-hole pairs can be greater than the lateral dimension of the Micro-LED. In this case, the electron-hole pairs injected into the active region will almost all diffuse to the device sidewalls. However, the high surface recombination rate of AlInGaP material leads to the majority of electrons and holes undergoing non-radiative recombination at the sidewalls. Even with sidewall passivation technology, the effect is far from ideal. Therefore, there is an urgent need for a new red Micro-LED structure that can fundamentally suppress sidewall recombination and improve the luminous efficiency of red Micro-LEDs. Summary of the Invention

[0004] To address the aforementioned technical problems in the existing technology, an embodiment of the present invention provides a red Micro-LED based on an InP quantum dot hydrazine layer and a method for fabricating the same.

[0005] A red Micro-LED according to one aspect of an embodiment of the present invention includes: a substrate; an AlGaInP barrier layer disposed on the substrate; and an InP quantum dot hydrazine layer stacked on the AlGaInP barrier layer.

[0006] In one example of the red Micro-LED provided above, the red Micro-LED further includes an N-type contact layer, an N-type barrier layer, a lower AlGaInP barrier layer, an upper AlGaInP barrier layer, a P-type barrier layer, a P-type conductive layer, a P-type window layer, a first electrode, and a second electrode; wherein the N-type contact layer, the N-type barrier layer, the lower AlGaInP barrier layer, the InP quantum dot hydrazine layer, the upper AlGaInP barrier layer, the P-type barrier layer, the P-type conductive layer, and the P-type window layer are sequentially stacked on the substrate in a direction away from the substrate, the first electrode is disposed on the P-type window layer, and the second electrode is in contact with the N-type contact layer.

[0007] In one example of the red Micro-LED provided above, the number of both the lower AlGaInP barrier layer and the InP quantum dot hydrazine layer is N, and the N-layer lower AlGaInP barrier layer and the N-layer InP quantum dot hydrazine layer are alternately stacked, wherein N is 5 to 10.

[0008] In one example of the red Micro-LED provided above, the N-type barrier layer, the lower AlGaInP barrier layer, the InP quantum dot hydrazine layer, the upper AlGaInP barrier layer, the P-type barrier layer, the P-type conductive layer, and the P-type window layer are partially etched away to form a mesa structure exposing the N-type contact layer, and the second electrode is disposed on the exposed N-type contact layer.

[0009] In one example of the red Micro-LED provided above, the substrate is an N-type GaAs substrate; and / or the N-type contact layer is an N-type GaInP material; and / or the N-type barrier layer is an N-type AlInP material; and / or the P-type barrier layer is a P-type AlInP material; and / or the P-type conductive layer is a P-type AlGaInP material; and / or the P-type window layer is a P-type GaP material.

[0010] A method for fabricating a red Micro-LED according to another aspect of the present invention includes: forming an AlGaInP barrier layer on a substrate using AlGaInP material, and forming an InP quantum dot hydrazine layer stacked with the AlGaInP barrier layer using InP quantum dots.

[0011] In one example of the method for fabricating a red Micro-LED provided in the other aspect above, before forming the AlGaInP barrier layer, the method further includes: sequentially forming an N-type contact layer and an N-type barrier layer on a substrate; forming the AlGaInP barrier layer using AlGaInP material includes: forming a lower AlGaInP barrier layer on the N-type barrier layer using AlGaInP material; forming an InP quantum dot hydrazine layer using InP quantum dots includes: forming an InP quantum dot hydrazine layer on the lower AlGaInP barrier layer using InP quantum dots; forming the AlGaInP barrier layer using AlGaInP material further includes: forming an upper AlGaInP barrier layer on the InP quantum dot hydrazine layer using AlGaInP material; after forming the upper AlGaInP barrier layer, the method further includes: sequentially forming a P-type barrier layer, a P-type conductive layer, and a P-type window layer on the upper AlGaInP barrier layer; depositing a first electrode on the P-type window layer and forming a second electrode in contact with the N-type contact layer.

[0012] In one example of the method for fabricating a red Micro-LED provided in the other aspect above, the number of both the lower AlGaInP barrier layer and the InP quantum dot hydrazine layer is N layers, and the N-layer lower AlGaInP barrier layer and the N-layer InP quantum dot hydrazine layer are alternately stacked, wherein N is 5 to 10.

[0013] In one example of the method for fabricating a red Micro-LED provided in the other aspect above, the method for depositing a first electrode on the P-type window layer and forming a second electrode in contact with the N-type contact layer includes: partially etching away the N-type barrier layer, the lower AlGaInP barrier layer, the InP quantum dot hydrazine layer, the upper AlGaInP barrier layer, the P-type barrier layer, the P-type conductive layer, and the P-type window layer to form a mesa structure exposing the N-type contact layer; fabricating a second electrode on the exposed N-type contact layer; and depositing a first electrode on the P-type window layer.

[0014] In one example of the method for fabricating a red Micro-LED provided in the other aspect above, the substrate is an N-type GaAs substrate; and / or the N-type contact layer is an N-type GaInP material; and / or the N-type barrier layer is an N-type AlInP material; and / or the P-type barrier layer is a P-type AlInP material; and / or the P-type conductive layer is a P-type AlGaInP material; and / or the P-type window layer is a P-type GaP material.

[0015] Beneficial effects: The red Micro-LED and its manufacturing method according to embodiments of the present invention have the following advantages:

[0016] (1) After electrons and holes are injected, they are confined in the local InP quantum dots, reducing the probability of diffusion to the sidewalls and surface recombination, thus effectively solving the surface recombination problem of small-sized devices;

[0017] (2) InP quantum dots do not have the problem of direct and indirect band competition in existing AlGaInP quantum hydrazine materials, resulting in high quantum efficiency and better temperature stability;

[0018] (3) The emission wavelength of InP quantum dots can be adjusted by the size of the InP quantum dots, and the controllable range is large. Attached Figure Description

[0019] The above and other aspects, features, and advantages of embodiments of the present invention will become clearer from the following description taken in conjunction with the accompanying drawings, in which:

[0020] Figure 1 This is a schematic diagram illustrating the physical explanation for the low quantum efficiency of existing red Micro-LED technologies.

[0021] Figure 2 This is a schematic diagram illustrating the physical explanation of the high quantum efficiency of red Micro-LED according to an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the structure of a red Micro-LED according to an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram comparing the luminous efficiency of a Micro-LED using InP quantum dots according to an embodiment of the present invention and a Micro-LED using AlGaInP quantum hydrazine in the prior art as a function of current density.

[0024] Figure 5 This is a schematic diagram of a substrate provided in a method for fabricating a red Micro-LED according to an embodiment of the present invention;

[0025] Figure 6 This is a schematic diagram of the sequential growth of layers on a substrate in a method for fabricating a red Micro-LED according to an embodiment of the present invention;

[0026] Figure 7 This is a schematic diagram of forming a mesa structure in a method for manufacturing a red Micro-LED according to an embodiment of the present invention;

[0027] Figure 8 This is a schematic diagram of the formation of a first electrode and a second electrode in a method for fabricating a red Micro-LED according to an embodiment of the present invention. Detailed Implementation

[0028] Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention can be implemented in many different forms, and should not be construed as limited to the specific embodiments set forth herein. Rather, these embodiments are provided to explain the principles of the invention and its practical application, thereby enabling others skilled in the art to understand the various embodiments of the invention and various modifications suitable for particular intended applications.

[0029] As used herein, the term "comprising" and its variations are open terms meaning "including but not limited to". The terms "based on", "according to", etc., mean "at least partially based on" or "at least partially based on". The terms "embodiment", "an example", "one embodiment", and "an embodiment" mean "at least one embodiment". The terms "another embodiment", "another embodiment", "another example", "yet another example" mean "at least one other embodiment". The terms "first", "second", etc., may refer to different or the same objects. Other definitions, whether explicit or implicit, may be included below. Unless explicitly indicated by the context, the definition of a term remains consistent throughout the specification.

[0030] It should also be noted that, in order to avoid obscuring the invention with unnecessary details, only the structures and / or processing steps closely related to the solution according to the invention are shown in the accompanying drawings, while other details that are not closely related are omitted.

[0031] As described in the background section, the external quantum efficiency of traditional small-sized red Micro-LEDs based on AlInGaP quantum hydrazine is only around 1-3%. The main reason is that the electron-hole pairs injected into the active region will diffuse to the device sidewalls for non-radiative recombination, resulting in a decrease in the radiative recombination efficiency of the Micro-LED.

[0032] Therefore, to solve the above problems, an embodiment of the present invention provides a red-light Micro-LED. When InP material is epitaxially grown on a GaAs substrate, because the lattice parameter of InP (5.8687 Å) is larger than that of GaAs (5.65325 Å), the InP material will grow in the SK mode (three-dimensional mode) under stress, spontaneously forming InP quantum dots. By controlling the size and density of the quantum dots, red light emission can be achieved. (Refer to...) Figure 2According to embodiments of the present invention, InP quantum dots are employed. The significant difference in conduction bands between AlInGaP and InP provides a high potential barrier, preventing injected electrons and holes from escaping and confining them to the InP quantum dots for radiative recombination. This reduces the probability of diffusion to the sidewalls for surface recombination, effectively solving the surface recombination problem in small-sized devices. Furthermore, InP quantum dots do not suffer from the direct and indirect band competition problem found in existing AlGaInP quantum dot materials, resulting in high quantum efficiency and better temperature stability. Moreover, the emission wavelength of InP quantum dots can be tuned by their size, offering a wide controllable range. For example, by controlling the size of the InP quantum dots, Micro-LED emission can be regulated between 600 and 680 nm, thereby achieving a 625 nm red Micro-LED.

[0033] Figure 3 This is a schematic diagram of the structure of an infrared detector according to an embodiment of the present invention.

[0034] Reference Figure 3 According to an embodiment of the present invention, a red Micro-LED includes: a substrate 10; an N-type contact layer 11, an N-type barrier layer 12, a lower AlGaInP barrier layer 13, an InP quantum dot well layer 14, an upper AlGaInP barrier layer 15, a P-type barrier layer 16, a P-type conductive layer 17, and a P-type window layer 18 stacked on the substrate 10 from bottom to top, i.e., stacked sequentially in a direction away from the substrate 10; a first electrode 19 disposed on the P-type window layer 18; and a second electrode 20 in contact with the N-type contact layer 11.

[0035] In one example, the substrate 10 can be an N-type GaAs substrate.

[0036] In one example, the N-type contact layer 11 can be an N-type GaInP material, the thickness of the N-type contact layer 11 can be 0.2µm~0.5µm, the doping source can be Si, and the doping concentration can be 1×10⁻⁶. 18 cm -3 ~1×10 19 cm -3 .

[0037] In one example, the N-type barrier layer 12 can be an N-type AlInP material, the thickness of the N-type barrier layer 12 can be 50nm~100nm, the doping source can be Si, and the doping concentration can be 1×10⁻⁶. 18 cm -3 ~5×10 18 cm -3 .

[0038] In one example, the lower AlGaInP barrier layer 13 can be an undoped AlGaInP material (i.e., the lower AlGaInP barrier layer), and the thickness of the lower AlGaInP barrier layer 13 can be 10 nm to 20 nm.

[0039] In one example, the InP quantum dot well layer 14 can be composed of InP quantum dots. The quantum dot size is 10nm~50nm, but the present invention is not limited to this, and the quantum dot size can be adjusted according to the actual application.

[0040] In one example, the lower AlGaInP barrier layer 13 and the InP quantum dot well layer 14 constitute a repeating unit with a repetition period of 5 to 10. That is, both the lower AlGaInP barrier layer 13 and the InP quantum dot well layer 14 are N layers (N is 5 to 10), and the N-layer lower AlGaInP barrier layer 13 and the N-layer InP quantum dot well layer are stacked alternately. In this repeating unit, the lowermost layer is the lower AlGaInP barrier layer 13, and the uppermost layer is the InP quantum dot well layer 14.

[0041] In one example, the upper AlGaInP barrier layer 15 can be an undoped AlGaInP material, and the thickness of the upper AlGaInP barrier layer 15 can be 10 nm to 20 nm. Therefore, the lower AlGaInP barrier layer 13 (or N-layer lower AlGaInP barrier layer 13) and the upper AlGaInP barrier layer constitute an AlGaInP barrier layer.

[0042] In one example, the P-type barrier layer 16 can be a P-type AlInP material, the thickness of the P-type barrier layer 16 can be 50nm~100nm, the doping source can be Mg, and the doping concentration can be 1×10⁻⁶. 17 cm -3 ~1×10 18 cm -3 .

[0043] In one example, the P-type conductive layer 17 can be a P-type AlGaInP material, the thickness of the P-type conductive layer 17 can be 0.2µm~0.5µm, the doping source can be Mg, and the doping concentration can be 1×10⁻⁶. 18 cm -3 ~1×10 19 cm -3 .

[0044] In one example, the P-type window layer 18 can be a P-type GaP material, the thickness of the P-type window layer 18 can be 2µm~5µm, the doping source can be Mg or C, and the doping concentration can be 5×10⁻⁶. 18 cm -3 ~1×1019 cm -3 .

[0045] In one example, the first electrode 19 is Ti / Au, but the present invention is not limited thereto.

[0046] In one example, the second electrode 20 is Au / Ge / Ni / Au, but the present invention is not limited thereto.

[0047] Figure 4 This diagram illustrates a comparison of the luminous efficiency of a Micro-LED using InP quantum dots according to an embodiment of the present invention and a Micro-LED using AlGaInP quantum hydrazine in the prior art, as a function of current density. The two are identical in structure except for the well layer; both emit light at 625 nm and have dimensions of 10 μm × 10 μm.

[0048] Reference Figure 4 It can be seen at 10A / cm 2 At a current density of [specific value], the quantum efficiency of the Micro-LED according to the embodiments of the present invention is improved by 67%. Therefore, the red Micro-LED based on InP quantum dots according to the embodiments of the present invention has significant advantages over the prior art.

[0049] The manufacturing process of red Micro-LED according to an embodiment of the present invention will be described in detail below. Figures 5 to 8 The fabrication process of a red Micro-LED according to an embodiment of the present invention is illustrated; wherein, Figure 5 This is a schematic diagram of a substrate provided in a method for fabricating a red Micro-LED according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the sequential growth of layers on a substrate in a method for fabricating a red Micro-LED according to an embodiment of the present invention; Figure 7 This is a schematic diagram of forming a mesa structure in a method for manufacturing a red Micro-LED according to an embodiment of the present invention; Figure 8 This is a schematic diagram of the formation of a first electrode and a second electrode in a method for fabricating a red Micro-LED according to an embodiment of the present invention.

[0050] First, refer to Figure 5 A substrate 10 is provided. In one example, the substrate 10 may be an N-type GaAs substrate.

[0051] Secondly, refer to Figure 6 An N-type contact layer 11, an N-type barrier layer 12, a lower AlGaInP barrier layer 13, an InP quantum dot well layer 14, an upper AlGaInP barrier layer 15, a P-type barrier layer 16, a P-type conductive layer 17, and a P-type window layer 18 are sequentially grown on the substrate 10 from bottom to top.

[0052] In one example, an N-type contact layer 11, an N-type barrier layer 12, a lower AlGaInP barrier layer 13, an InP quantum dot well layer 14, an upper AlGaInP barrier layer 15, a P-type barrier layer 16, a P-type conductive layer 17, and a P-type window layer 18 are sequentially grown from bottom to top on the substrate 10 using a metal-organic chemical vapor deposition (MOCVD) process.

[0053] Specifically, metal-organic chemical vapor deposition (MOCVD) was used as the growth process, with TMIn, TMGa, TMAl, AsH3, and PH3 as growth sources, SiH4 as the n-type dopant source, and Cp2Mg and CBr4 as the p-type dopant sources. The growth temperature was set to approximately 800℃, and the reaction chamber pressure was set to 100 Torr. After removing impurities from the surface of substrate 10 through high-temperature treatment, the following materials were grown sequentially on substrate 10 from bottom to top:

[0054] (a) N-type contact layer 11 is made of N-type GaInP material, with a thickness of 0.25µm, doped with Si, and the doping concentration is 3×10⁻⁶. 18 cm -3 .

[0055] (ii) N-type barrier layer 12, made of N-type AlInP material, 100 nm thick, doped with Si, with a doping concentration of 1 × 10⁻⁶. 18 cm -3 .

[0056] (iii) The lower AlGaInP barrier layer is an undoped AlGaInP material with a thickness of 15nm.

[0057] (iv) InP quantum dot well layer 14, which is an InP quantum dot with a quantum dot size of 20nm.

[0058] (v) Repeat the process of the lower AlGaInP barrier layer 13 and the InP quantum dot well layer 14 8 times. The 8 layers of lower AlGaInP barrier layer 13 and the 8 layers of InP quantum dot well layer 14 are stacked alternately, with the lower AlGaInP barrier layer 13 being the bottom layer and the InP quantum dot well layer 14 being the top layer.

[0059] (vi) The AlGaInP barrier layer 15 is an undoped AlGaInP material with a thickness of 15nm.

[0060] (vii) P-type barrier layer 16, made of P-type AlInP material, with a thickness of 50 nm, doped with Mg, with a doping concentration of 5 × 10⁻⁶. 17 cm -3 .

[0061] (viii) P-type conductive layer 17, made of P-type AlGaInP material, with a thickness of 0.25µm, doped with Mg, with a doping concentration of 5×10⁻⁶. 18 cm -3 .

[0062] (ix) P-type window layer 18, made of P-type GaP material, with a thickness of 3µm, C-doped, with a doping concentration of 8×10⁻⁶. 18 cm -3 .

[0063] Next, refer to Figure 7 The P-type window layer 18, the P-type conductive layer 17, the P-type barrier layer 16, the upper AlGaInP barrier layer 15, the InP quantum dot well layer 14, the lower AlGaInP barrier layer 13, and the N-type barrier layer 12 are locally etched to form a mesa structure A that exposes the N-type contact layer 11.

[0064] In one example, inductively coupled plasma etching (ICP) is used to locally etch the P-type window layer 18, the P-type conductive layer 17, the P-type barrier layer 16, the upper AlGaInP barrier layer 15, the InP quantum dot well layer 14, the lower AlGaInP barrier layer 13, and the N-type barrier layer 12, exposing the N-type contact layer 11 to form a mesa structure A.

[0065] In one example, the dimensions of the platform structure A are 20μm × 20μm.

[0066] Finally, refer to Figure 8 A first electrode 19 is deposited on the P-type window layer 18, and a second electrode 20 is deposited on the exposed N-type contact layer 11.

[0067] In one example, an electron beam evaporation process is used to deposit a first electrode 19 on the exposed P-type window layer 18 and a second electrode 20 on the exposed N-type contact layer 11.

[0068] The first electrode 19 is Ti(500Å) / Au(3000Å), and the second electrode 20 is Au(50Å) / Ge(200Å) / Ni(200Å) / Au(3000Å).

[0069] In summary, the red Micro-LED according to the embodiments of the present invention uses an InP quantum dot well layer instead of the well layer in the AlGaInP quantum dot in the prior art to confine electrons and holes in the quantum dots to emit light, thereby suppressing the lateral diffusion of charge carriers, effectively suppressing sidewall recombination in small-sized devices, and improving the luminous efficiency of Micro-LED.

[0070] The optional embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above embodiments. Within the scope of the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all fall within the protection scope of the embodiments of the present invention.

Claims

1. A red Micro-LED, characterized in that, The red Micro-LED comprises: a substrate (10); an AlGaInP barrier layer disposed on the substrate (10); an InP quantum dot layer (14) stacked on the AlGaInP barrier layer; The red Micro-LED further comprises an N-type contact layer (11), an N-type barrier layer (12), a lower AlGaInP barrier layer (13), an upper AlGaInP barrier layer (15), a P-type barrier layer (16), a P-type conductive layer (17), a P-type window layer (18), a first electrode (19), and a second electrode (20). The N-type contact layer (11), the N-type barrier layer (12), the lower AlGaInP barrier layer (13), the InP quantum dot layer (14), the upper AlGaInP barrier layer (15), the P-type barrier layer (16), the P-type conductive layer (17), and the P-type window layer (18) are sequentially stacked on the substrate (10) in a direction away from the substrate (10), the first electrode (19) is disposed on the P-type window layer (18), and the second electrode (20) is in contact with the N-type contact layer (11).

2. The red Micro-LED of claim 1, wherein, The lower AlGaInP barrier layer (13) and the InP quantum dot layer (14) are both N layers, and the N layers of the lower AlGaInP barrier layer (13) and the N layers of the InP quantum dot layer (14) are alternately stacked, wherein N is 5-10.

3. The red Micro-LED structure according to claim 1 or 2, characterized in that, The N-type barrier layer (12), the lower AlGaInP barrier layer (13), the InP quantum dot layer (14), the upper AlGaInP barrier layer (15), the P-type barrier layer (16), the P-type conductive layer (17), and the P-type window layer (18) are partially etched to form a mesa structure (A) exposing the N-type contact layer (11), and the second electrode (20) is disposed on the exposed N-type contact layer (11).

4. The red Micro-LED structure of claim 1, wherein, The substrate (10) is an N-type GaAs substrate; and / or the N-type contact layer (11) is an N-type GaInP material; and / or the N-type barrier layer (12) is an N-type AlInP material; and / or the P-type barrier layer (16) is a P-type AlInP material; and / or the P-type conductive layer (17) is a P-type AlGaInP material; and / or the P-type window layer (18) is a P-type GaP material.

5. A method for fabricating a red Micro-LED, characterized in that The manufacturing method comprises: forming an AlGaInP barrier layer on a substrate (10) using an AlGaInP material, and forming an InP quantum dot layer (14) stacked with the AlGaInP barrier layer using an InP quantum dot; Before forming the AlGaInP barrier layer, the manufacturing method further comprises sequentially forming a stacked N-type contact layer (11) and an N-type barrier layer (12) on the substrate (10); The AlGaInP material is used to form an AlGaInP barrier layer, which includes: using AlGaInP material to form a lower AlGaInP barrier layer (13) on the N-type barrier layer (12); The InP quantum dot is used to form an InP quantum dot hydride layer (14), which includes: using InP quantum dots to form an InP quantum dot hydride layer (14) on the lower AlGaInP barrier layer (13); The AlGaInP material is used to form an AlGaInP barrier layer, which further includes: using AlGaInP material to form an upper AlGaInP barrier layer (15) on the InP quantum dot hydride layer (14); After the upper AlGaInP barrier layer (15) is formed, the manufacturing method further includes: sequentially forming a stacked P-type barrier layer (16), a P-type conductive layer (17), and a P-type window layer (18) on the upper AlGaInP barrier layer (15); depositing a first electrode (19) on the P-type window layer (18), and forming a second electrode (20) in contact with the N-type contact layer (11).

6. The method of claim 5, wherein the red Micro-LED is formed by the following steps: depositing a red light emitting layer on the substrate; and depositing a red light emitting layer on the substrate. The number of the lower AlGaInP barrier layer (13) and the InP quantum dot hydride layer (14) is N layers, and N layers of the lower AlGaInP barrier layer (13) and N layers of the InP quantum dot hydride layer (14) are alternately stacked, wherein N is 5-10.

7. The method of claim 5 or 6, wherein the method further comprises: The method of depositing a first electrode (19) on the P-type window layer (18), and forming a second electrode (20) in contact with the N-type contact layer (11) includes: The N-type barrier layer (12), the lower AlGaInP barrier layer (13), the InP quantum dot hydride layer (14), the upper AlGaInP barrier layer (15), the P-type barrier layer (16), the P-type conductive layer (17), and the P-type window layer (18) are partially etched and removed to form a mesa structure (A) exposing the N-type contact layer (11); A second electrode (20) is formed on the exposed N-type contact layer (11), and a first electrode (19) is deposited on the P-type window layer (18).

8. The method of claim 5 or 6, wherein the method further comprises: The substrate (10) is an N-type GaAs substrate; and / or the N-type contact layer (11) is an N-type GaInP material; and / or the N-type barrier layer (12) is an N-type AlInP material; and / or the P-type barrier layer (16) is a P-type AlInP material; and / or the P-type conductive layer (17) is a P-type AlGaInP material; and / or the P-type window layer (18) is a P-type GaP material.

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