Micro-LED light source and preparation method thereof

Abstract

The application relates to the technical field of semiconductor display, in particular to a Micro-LED light source and a preparation method thereof. The Micro-LED light source comprises a substrate layer, a buffer layer located on one side surface of the substrate layer, a first n-type GaN layer located on one side surface of the buffer layer away from the substrate layer, a plurality of hollow cylindrical structures located on one side surface of the first n-type GaN layer away from the buffer layer, wherein the hollow cylindrical structure comprises a mesa structure, a passivation layer partially wrapping the mesa structure, a reflective electrode layer partially wrapping the passivation layer, and a gap formed by the passivation layer not wrapped by the reflective electrode layer and the first n-type GaN layer; and the gap is used for filling quantum dot solution. The application fills quantum dot solution into the gap part of the LED, thereby enhancing the absorption of blue light and the color conversion efficiency.

Description

Technical Field

[0001] This invention relates to the field of semiconductor display technology, and in particular to a Micro-LED light source and its fabrication method. Background Technology

[0002] Currently, the vast majority of full-color Micro-LED display products on the market employ color conversion technology. In this regard, semiconductor quantum dots (QDs) stand out due to their superior optical and physical properties, including a quantum yield exceeding 90%, tunable emission wavelength, large relative surface area, narrow emission spectrum, high photostability, and good solution processability, making them the mainstream material for color conversion. These characteristics not only provide a reliable path to achieving high-efficiency, high-performance color conversion layers but also pave the way for the development of quantum dot printing technology.

[0003] However, the color conversion scheme using blue-light Micro-LEDs to activate quantum dots has raised concerns about blue light leakage, optical crosstalk, and reduced brightness. Color conversion schemes in full-color Micro-LED displays typically require filters to eliminate unavoidable blue light leakage during the color conversion process. This method leads to some light energy loss and increases the complexity and cost of the manufacturing process. Recent studies have achieved significant improvements by using high-concentration quantum dot films, but the thickness of these films presents new challenges, such as low color conversion efficiency, crosstalk issues, and difficulties in manufacturing thick films.

[0004] Therefore, those skilled in the art are dedicated to developing a Micro-LED light source for full-color display that effectively reduces blue light leakage while achieving high efficiency and high brightness, as well as its fabrication method. Summary of the Invention

[0005] In view of the above-mentioned deficiencies of the prior art, the technical problem to be solved by the present invention is to provide a full-color display Micro-LED light source that effectively reduces blue light leakage while achieving high efficiency and high brightness, and a method for its preparation.

[0006] To achieve the above objectives, the present invention provides a Micro-LED light source and its preparation method, which enhances the color conversion effect by filling the gaps in the LED with quantum dot solution; and avoids the quantum dot layer transfer step by depositing quantum dots into the hollow part of the device, thereby minimizing crosstalk problems caused by bottom emission.

[0007] In a first aspect, the present invention provides a Micro-LED light source, comprising:

[0008] Substrate layer;

[0009] A buffer layer is located on one side surface of the substrate layer;

[0010] The first n-type GaN layer is located on the side surface of the buffer layer opposite to the substrate layer;

[0011] Several hollow cylindrical structures are located on the side surface of the first n-type GaN layer away from the buffer layer. Each hollow cylindrical structure includes a mesa structure, a passivation layer that partially encloses the mesa structure, a reflective electrode layer that partially encloses the passivation layer, and a void formed between the passivation layer not enclosed by the reflective electrode layer and the first n-type GaN layer. The void is used to fill a quantum dot solution.

[0012] Preferably, the countertop structure includes:

[0013] The second n-type GaN layer is located on the surface of the first n-type GaN layer that is away from the buffer layer;

[0014] The third n-type GaN layer is located on the surface of the second n-type GaN layer that is away from the first n-type GaN layer.

[0015] The second multiple quantum well structure layer is located on the side surface of the third n-type GaN layer that is away from the second n-type GaN layer;

[0016] The second p-type GaN layer is located on the side surface of the second multiple quantum well structure layer that is away from the third n-type GaN layer;

[0017] A current diffusion layer is located on the surface of the second p-type GaN layer away from the second multiple quantum well structure layer.

[0018] Preferably, the widths of the first n-type GaN layer, the second n-type GaN layer, and the third n-type GaN layer decrease sequentially; the widths of the third n-type GaN layer, the second multiple quantum well structure layer, the second p-type GaN layer, and the current diffusion layer are the same.

[0019] Preferably, the quantum dot solution comprises CdSe (cadmium selenide) / ZnS (zinc sulfide) red quantum dots and green quantum dots.

[0020] Preferably, it also includes scattering particles that fill the gaps.

[0021] Preferably, the thickness of the passivation layer is in the range of 1.0-2.0 μm.

[0022] In a second aspect, the present invention also provides a method for fabricating a Micro-LED light source, comprising:

[0023] Provide a substrate layer;

[0024] A buffer layer is formed on one side surface of the substrate layer;

[0025] A first n-type GaN layer is formed on the surface of the buffer layer opposite to the substrate layer;

[0026] A plurality of hollow cylindrical structures are formed on the side surface of the first n-type GaN layer away from the buffer layer; the hollow cylindrical structure includes a mesa structure, a passivation layer that partially encloses the mesa structure, a reflective electrode layer that partially encloses the passivation layer, and a gap formed between the passivation layer not enclosed by the reflective electrode layer and the first n-type GaN layer; the gap is used to fill quantum dot solution.

[0027] Preferably, forming a plurality of hollow cylindrical structures on the surface of the first n-type GaN layer away from the buffer layer includes:

[0028] On the side of the first n-type GaN layer away from the buffer layer, InGaN or AlGaN quantum well layers and GaN quantum barrier layers of different compositions and thicknesses are alternately grown to form a first multi-quantum well structure layer.

[0029] A first p-type GaN layer is grown on the surface of the first multi-quantum-well structure layer that is away from the first n-type GaN layer;

[0030] Laser lithography is performed from the first p-type GaN layer to the first n-type GaN layer using a maskless alignment instrument, and two steps are etched using inductively coupled plasma to form the second n-type GaN layer, the third n-type GaN layer, and the second multiple quantum well structure layer and the second p-type GaN layer with the same width as the third n-type GaN layer.

[0031] A current diffusion layer is grown on the surface of the second p-type GaN layer on the side opposite to the second multiple quantum well structure layer;

[0032] A passivation layer is grown from the current diffusion layer to the surface of the first n-type GaN layer, and the passivation layer forms a void with one side surface of the first n-type GaN layer.

[0033] Preferably, the passivation layer is grown using the following methods:

[0034] A passivation layer was deposited on the surface of the mesa structure by plasma-enhanced chemical vapor deposition. The deposition temperature was 290-310℃, the gas flow rate was SiH4:N2O=1:3, the deposition rate was 90-110nm / min, and the deposition thickness was 1.0-2.0μm.

[0035] Preferably, CdSe (cadmium selenide) / ZnS (zinc sulfide) red and green quantum dots are printed into the void region using an electric inkjet printing method.

[0036] The beneficial effects of this invention are as follows: This invention enhances color conversion by filling the hollow portion of the LED with quantum dot solution. It utilizes inkjet printing technology to directly deposit quantum dots into the hollow space of the device, avoiding the quantum dot layer transfer step and minimizing crosstalk issues caused by bottom emission. A current diffusion layer is applied to the surface of the mesa structure, and combined with adjustments to the passivation layer thickness, the emission angle can be controlled. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the Micro-LED light source structure in some embodiments of the present invention.

[0038] Figure 2 This is a schematic diagram of the Micro-LED light source hierarchical structure in some embodiments of the present invention;

[0039] Figure 3 This is a schematic diagram of the etching structure of the Micro-LED light source in some embodiments of the present invention;

[0040] Figure 4 This is a schematic diagram of the Micro-LED light source diffusion structure in some embodiments of the present invention;

[0041] Figure 5 This is a schematic diagram of the passivation structure of the Micro-LED light source in some embodiments of the present invention;

[0042] Figure 6 This is a schematic diagram of the three-dimensional structure of the Micro-LED light source in some embodiments of the present invention;

[0043] Figure 7 This is a flowchart of the Micro-LED light source fabrication method in some embodiments of the present invention;

[0044] Figure 8 These are color conversion spectra comparison diagrams of some embodiments of the present invention and traditional quantum dot films;

[0045] Figure 9 This is a graph showing the relationship between brightness and current density in some embodiments of the present invention;

[0046] Figure 10 This is a light emission angle distribution diagram of some embodiments of the present invention. Detailed Implementation

[0047] The present invention will be further described below with reference to the accompanying drawings and embodiments. It should be noted that in the description of the present invention, terms such as "upper," "lower," "left," "right," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only for the convenience of describing the present invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific manner. Therefore, they should not be construed as limitations on the present invention. Terms such as "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0048] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0049] This application provides a Micro-LED light source and a method for fabricating a Micro-LED light source. These will be described in detail below. It should be noted that the order of description of the following embodiments is not intended to limit the preferred order of the embodiments.

[0050] like Figure 1 As shown, Figure 1 This is a schematic diagram of a Micro-LED light source structure according to a specific embodiment of the present invention, including:

[0051] Substrate layer 11;

[0052] A buffer layer 21 is located on one side surface of the substrate layer 11;

[0053] The first n-type GaN layer 31 is located on the side surface of the buffer layer 21 that is away from the substrate layer 11;

[0054] Several hollow cylindrical structures are located on the side surface of the first n-type GaN layer 31 facing away from the buffer layer 21. The hollow cylindrical structure includes a mesa structure, a passivation layer 71 that partially encloses the mesa structure, a reflective electrode layer 91 that partially encloses the passivation layer 71, and a gap 81 formed between the passivation layer not enclosed by the reflective electrode layer 91 and the first n-type GaN layer 31; the gap 81 is used to fill quantum dot solution.

[0055] In this embodiment, by covering the surface of the table structure with a reflective electrode layer 91 and adjusting the thickness of the passivation layer 71, the emission angle can be controlled. By filling the gaps 81 formed in the table structure with quantum dot solution, the color conversion effect can be enhanced. This method does not require transferring the quantum dot layer to the Micro-LED surface and effectively reduces blue light leakage, while achieving a high-efficiency, high-brightness full-color display effect.

[0056] The following will combine Figures 1-6The structure of this application will be described in detail.

[0057] In this embodiment of the application, the tabletop structure includes:

[0058] The second n-type GaN layer 32 is located on the side surface of the first n-type GaN layer 31 that is away from the buffer layer 21;

[0059] The third n-type GaN layer 33 is located on the side surface of the second n-type GaN layer 32 that is away from the first n-type GaN layer 31;

[0060] The second multiple quantum well structure layer 42 is located on the side surface of the third n-type GaN layer 33 that is away from the second n-type GaN layer 32;

[0061] The second p-type GaN layer 52 is located on the side surface of the second multiple quantum well structure layer 42 that is away from the third n-type GaN layer 33;

[0062] The current diffusion layer 61 is located on the side surface of the second p-type GaN layer 52 that is away from the second multiple quantum well structure layer 42.

[0063] In this embodiment of the invention, the widths of the first n-type GaN layer 31, the second n-type GaN layer 32, and the third n-type GaN layer 33 decrease sequentially to form a stepped structure; the widths of the third n-type GaN layer 33, the second multiple quantum well structure layer 42, the second p-type GaN layer 52, and the current diffusion layer 61 are the same.

[0064] In some embodiments of the present invention, the quantum dot solution comprises CdSe (cadmium selenide) / ZnS (zinc sulfide) red quantum dots and green quantum dots.

[0065] In some preferred embodiments of the present invention, scattering particles are also included to fill the gaps. The role of scattering particles in LEDs is mainly to enhance light scattering and absorption. When blue light shines on the scattering particles, the particles scatter the light in various directions, thereby increasing the chance of light contacting the quantum dots. In addition, scattering particles can also improve the absorption efficiency of quantum dots for blue light, allowing more blue light to be absorbed by the quantum dots and converted into red (green) light. Combining scattering particles with quantum dots can further optimize the light color conversion efficiency of LEDs. The addition of scattering particles not only enhances light scattering and absorption but also makes the distribution of quantum dots in LEDs more uniform. This helps to improve the light emission uniformity and color purity of LEDs. At the same time, scattering particles can also reduce the direct leakage of blue light in LEDs, thereby improving color conversion efficiency.

[0066] A method for fabricating a Micro-LED light source, such as Figure 7 As shown, the method includes:

[0067] 101. Provide a substrate layer;

[0068] 102. A buffer layer is formed on one side surface of the substrate layer;

[0069] 103. A first n-type GaN layer is formed on the surface of the buffer layer opposite to the substrate layer;

[0070] 104. A plurality of hollow cylindrical structures are formed on the side surface of the first n-type GaN layer away from the buffer layer; the hollow cylindrical structure includes a mesa structure, a passivation layer that partially encloses the mesa structure, a reflective electrode layer that partially encloses the passivation layer, and a gap formed between the passivation layer not enclosed by the reflective electrode layer and the first n-type GaN layer; the gap is used to fill quantum dot solution.

[0071] In some embodiments of this application, after providing the substrate layer in step 101, the exposed epitaxial wafer can also be cleaned using standard cleaning methods. In some embodiments of this application, forming a plurality of hollow cylindrical structures on the surface of the first n-type GaN layer away from the buffer layer includes:

[0072] On the side of the first n-type GaN layer away from the buffer layer, InGaN or AlGaN quantum well layers and GaN quantum barrier layers of different compositions and thicknesses are alternately grown to form a first multi-quantum well structure layer.

[0073] A first p-type GaN layer is grown on the surface of the first multi-quantum-well structure layer that is away from the first n-type GaN layer;

[0074] In some embodiments of this application, the following can be formed: Figure 2 The layered structure shown includes a substrate layer 11; a buffer layer 21 located on one side surface of the substrate layer 11; a first n-type GaN layer 31 located on the side surface of the buffer layer 21 opposite to the substrate layer 11; a first multi-quantum-well structure layer 41 located on the side surface of the first n-type GaN layer 31 opposite to the buffer layer 21; and a first p-type GaN layer 51 located on the side surface of the first multi-quantum-well structure layer 41 opposite to the first n-type GaN layer 31.

[0075] Laser lithography is performed using a maskless alignment device from the first p-type GaN layer to the first n-type GaN layer, followed by two-step inductively coupled plasma etching to form a second n-type GaN layer, a third n-type GaN layer, and a second multiple quantum well structure layer and a second p-type GaN layer with the same width as the third n-type GaN layer; in some embodiments of this application, the following can be formed: Figure 3The etched structure shown includes a substrate layer 11; a buffer layer 21 located on one side surface of the substrate layer 11; a first n-type GaN layer 31 located on the side surface of the buffer layer 21 opposite to the substrate layer 11; a second n-type GaN layer 32 located on the side surface of the first n-type GaN layer 31 opposite to the buffer layer 21; a third n-type GaN layer 33 located on the side surface of the second n-type GaN layer 32 opposite to the first n-type GaN layer 31; a second multiple quantum well structure layer 42 located on the side surface of the third n-type GaN layer 33 opposite to the second n-type GaN layer 32; and a second p-type GaN layer 52 located on the side surface of the second multiple quantum well structure layer 42 opposite to the third n-type GaN layer 33.

[0076] A current diffusion layer is grown on the surface of the second p-type GaN layer on the side opposite to the second multiple quantum well structure layer;

[0077] In some embodiments of this application, the following can be formed: Figure 4 The diffusion structure shown includes a substrate layer 11; a buffer layer 21 located on one side surface of the substrate layer 11; a first n-type GaN layer 31 located on the side surface of the buffer layer 21 opposite to the substrate layer 11; a second n-type GaN layer 32 located on the side surface of the first n-type GaN layer 31 opposite to the buffer layer 21; a third n-type GaN layer 33 located on the side surface of the second n-type GaN layer 32 opposite to the first n-type GaN layer 31; a second multiple quantum well structure layer 42 located on the side surface of the third n-type GaN layer 33 opposite to the second n-type GaN layer 32; a second p-type GaN layer 52 located on the side surface of the second multiple quantum well structure layer 42 opposite to the third n-type GaN layer 33; and a current diffusion layer 61 located on the side surface of the second p-type GaN layer 52 opposite to the second multiple quantum well structure layer 42.

[0078] A passivation layer is grown from the current diffusion layer to the surface of the first n-type GaN layer, and the passivation layer forms a void with one side surface of the first n-type GaN layer.

[0079] In some embodiments of this application, the following can be formed: Figure 5The passivation structure shown includes a substrate layer 11; a buffer layer 21 located on one side surface of the substrate layer 11; a first n-type GaN layer 31 located on the side surface of the buffer layer 21 opposite to the substrate layer 11; a second n-type GaN layer 32 located on the side surface of the first n-type GaN layer 31 opposite to the buffer layer 21; a third n-type GaN layer 33 located on the side surface of the second n-type GaN layer 32 opposite to the first n-type GaN layer 31; a second multiple quantum well structure layer 42 located on the side surface of the third n-type GaN layer 33 opposite to the second n-type GaN layer 32; a second p-type GaN layer 52 located on the side surface of the second multiple quantum well structure layer 42 opposite to the third n-type GaN layer 33; a current diffusion layer 61 located on the side surface of the second p-type GaN layer 52 opposite to the second multiple quantum well structure layer 42; and a passivation layer 71 partially enclosing the mesa structure, wherein the passivation layer 71 and the first n-type GaN layer 31 form a gap 81.

[0080] It should be noted that the present invention does not impose specific limitations on the depth and diameter of the gap 81, i.e., the hollow cylinder. In some embodiments of this application, Ni / Au (5 / 5nm) is deposited by electron beam evaporation, followed by photolithography lift-off to form a current diffusion layer.

[0081] In some embodiments of this application, rapid heat treatment at 570°C is performed to form a p-type ohmic contact; a p-type ohmic contact refers to a contact with good electronic conductivity formed between a p-type semiconductor and a metal. In this type of contact, the contact resistance is very small, almost negligible, so current can flow smoothly through the contact interface; the p-type ohmic contact can reduce contact resistance.

[0082] The methods for growing passivation layers include:

[0083] A passivation layer is deposited on the surface of the mesa structure by plasma-enhanced chemical vapor deposition. The deposition temperature is 290-310℃, the gas flow rate is SiH4:N2O=1:3, the deposition rate is 90-110nm / min, and the deposition thickness is 1.0-2.0μm, for example, 1.5μm.

[0084] The quantum dot solution filling the voids comprises:

[0085] CdSe (cadmium selenide) and ZnS (zinc sulfide) red and green quantum dots were printed into the void region using an electric inkjet printing method.

[0086] In this embodiment, Ti / Al / Ti / Au (20 / 150 / 50 / 100nm) is deposited as the reflective electrode layer via electron beam evaporation. By covering the mesa structure with a reflective metal layer and adjusting the thickness of the passivation layer, the emission angle can be controlled. This method transforms traditional vertical surface emission into horizontal emission, significantly reducing blue light leakage and optimizing the interaction between light and quantum dots.

[0087] The Micro-LED light source structure provided in this embodiment firstly achieves precise control of the Micro-LED emission angle through a two-step step etching process, the application of a thick passivation layer, and the layout of the peripheral reflective electrodes. This design transforms traditional vertical surface emission into horizontal emission, significantly reducing blue light leakage and optimizing the interaction between light and quantum dots. By filling the hollow part of the LED with quantum dot solution, combined with the addition of scattering particles, the absorption of blue light and color conversion efficiency are enhanced. Experiments show that this invention has significant advantages in reducing blue light leakage, improving conversion efficiency, and achieving high brightness output. Furthermore, the direct deposition of quantum dots in the hollow region using inkjet printing technology simplifies the manufacturing process, improves the deposition accuracy and uniformity of quantum dots, and contributes to achieving high-performance full-color displays.

[0088] pass Figure 8 As can be seen, the blue light leakage of the Micro-LED power supply in this embodiment has a superior blue light leakage suppression effect compared with traditional color conversion schemes. In this application, with a hollow cylinder diameter of 100 μm (corresponding to a quantum dot film thickness of 2.5 μm), the blue light leakage ratios for green light (corresponding to HC-100-G) and red light (corresponding to HC-100-R) are only 5.3% and 2.1%, respectively. This is lower than the blue light leakage ratios of traditional planar quantum dot film solutions, which are 22.6% and 8.9% for green light (corresponding to BM-12μm-G) with a quantum dot film thickness of 12 μm and for red light (corresponding to BM-11μm-R) with a quantum dot film thickness of 11 μm. The brightness performance of the hollow cylindrical Micro-LED under different current densities is also demonstrated.

[0089] Figure 9 By demonstrating the relationship between brightness and current density, this application reveals the significant improvement in brightness performance of green (HC-50-GQD and HC-100-GQD) and red (HC-50-RQD and HC-100-RQD) arrays after integrating quantum dots in hollow cylinders with diameters of 50 and 100 μm. Particularly in the HC-100 array, taking a 10×10 quantum dot array as an example, the introduction of quantum dots not only achieved a significant increase in green light brightness, reaching 37 A / cm², but also... 2The HC-50 array achieved a high brightness level exceeding 10 knits at current density, with a red light brightness reaching 9600 nits. This achievement significantly surpasses the records for red and green light brightness set by traditional quantum dot color conversion technology. Similarly, the HC-50 array also demonstrated excellent performance, achieving a brightness exceeding 8000 nits at the same current density.

[0090] Traditional square Micro-LEDs (Rec-100) exhibit a typical Lambertian emission model, meaning their luminous intensity is concentrated at the center and gradually decreases towards the edges, with an overall emission angle of approximately 120°. In contrast, the Micro-LED light source of this invention exhibits a wider light divergence angle due to its unique hollow cylindrical structure design. This ultra-large divergence angle primarily stems from the structural design. Firstly, the reflective electrodes on the upper surface and periphery effectively reflect outwardly emitted light into the hollow center. After passing through the hollow structure, the light undergoes multiple internal scattering or reflections before escaping and being recorded by the detector. This multiple internal scattering or reflection means that some light energy is consumed as heat within the hollow structure, but it's worth noting that this is without quantum dots. However, the situation changes when quantum dots containing scattering particles are introduced. The participation of quantum dots further enhances the light scattering effect and enables the conversion of light at specific wavelengths, making it possible to achieve high-efficiency and high-uniformity full-color displays.

[0091] like Figure 10 As shown, the emission angle distribution diagrams of HC-50 and HC-100 devices reveal the highly efficient light concentration characteristics. HC-50's emission is mainly concentrated in the ranges of -75° to -55° and +55° to +75°, while HC-100's emission intensity distribution is even more concentrated, primarily located between -75° and -65° and +65° and +75°. This highly concentrated lateral emission characteristic is particularly advantageous for the color conversion of quantum dots, as the laterally concentrated divergence angle effectively confines the light within the hollow region, effectively lengthening the path length for light to interact with the quantum dot material in the hollow region, thereby enhancing the color conversion effect. In particular, the structural design of HC-Micro-LEDs causes light to escape the hollow structure only after multiple internal scattering or reflections, which not only increases the probability of light interacting with the quantum dots but also helps to achieve more uniform light output. In contrast, the Lambertian model emission distribution of traditional planar Micro-LEDs is mainly emitted from the top surface, a design that leads to blue light leakage and optical crosstalk problems.

[0092] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A Micro-LED light source, characterized in that, include: Substrate layer; A buffer layer is located on one side surface of the substrate layer; The first n-type GaN layer is located on the side surface of the buffer layer opposite to the substrate layer; Several hollow cylindrical structures are located on the side surface of the first n-type GaN layer away from the buffer layer. The hollow cylindrical structure includes a mesa structure, a passivation layer that partially wraps the mesa structure, a reflective electrode layer that partially wraps the passivation layer, and a gap formed between the passivation layer not wrapped by the reflective electrode layer and the first n-type GaN layer. The pores are used to fill the quantum dot solution; The platform structure includes: The second n-type GaN layer is located on the surface of the first n-type GaN layer that is away from the buffer layer; The third n-type GaN layer is located on the surface of the second n-type GaN layer that is away from the first n-type GaN layer. The second multiple quantum well structure layer is located on the side surface of the third n-type GaN layer that is away from the second n-type GaN layer; The second p-type GaN layer is located on the side surface of the second multiple quantum well structure layer that is away from the third n-type GaN layer; A current diffusion layer is located on the surface of the second p-type GaN layer away from the second multiple quantum well structure layer; The widths of the first n-type GaN layer, the second n-type GaN layer, and the third n-type GaN layer decrease sequentially; the widths of the third n-type GaN layer, the second multiple quantum well structure layer, the second p-type GaN layer, and the current diffusion layer are the same.

2. The Micro-LED light source as described in claim 1, characterized in that, The quantum dot solution includes CdSe (cadmium selenide) / ZnS (zinc sulfide) red quantum dots and green quantum dots.

3. The Micro-LED light source as described in claim 1 or 2, characterized in that, It also includes scattering particles that fill the gaps.

4. The Micro-LED light source as described in claim 1, characterized in that, The thickness of the passivation layer ranges from 1.0 to 2.0 μm.

5. A method for fabricating a Micro-LED light source, characterized in that, include: Provide a substrate layer; A buffer layer is formed on one side surface of the substrate layer; A first n-type GaN layer is formed on the surface of the buffer layer opposite to the substrate layer; A plurality of hollow cylindrical structures are formed on the side surface of the first n-type GaN layer away from the buffer layer; the hollow cylindrical structure includes a mesa structure, a passivation layer that partially encloses the mesa structure, a reflective electrode layer that partially encloses the passivation layer, and a gap formed between the passivation layer not enclosed by the reflective electrode layer and the first n-type GaN layer. The pores are used to fill the quantum dot solution; Forming a plurality of hollow cylindrical structures on the surface of the first n-type GaN layer away from the buffer layer includes: On the side of the first n-type GaN layer away from the buffer layer, InGaN or AlGaN quantum well layers and GaN quantum barrier layers of different compositions and thicknesses are alternately grown to form a first multi-quantum well structure layer. A first p-type GaN layer is grown on the surface of the first multi-quantum-well structure layer that is away from the first n-type GaN layer; Laser lithography is performed from the first p-type GaN layer to the first n-type GaN layer using a maskless alignment instrument, and two steps are etched using inductively coupled plasma to form the second n-type GaN layer, the third n-type GaN layer, and the second multiple quantum well structure layer and the second p-type GaN layer with the same width as the third n-type GaN layer. A current diffusion layer is grown on the surface of the second p-type GaN layer on the side opposite to the second multiple quantum well structure layer; A passivation layer is grown from the current diffusion layer to the surface of the first n-type GaN layer, and the passivation layer forms a void with one side surface of the first n-type GaN layer.

6. The method for fabricating a Micro-LED light source as described in claim 5, characterized in that, The methods for growing passivation layers include: A passivation layer was deposited on the surface of the mesa structure by plasma-enhanced chemical vapor deposition. The deposition temperature was 290-310℃, the gas flow rate was SiH4:N2O=1:3, the deposition rate was 90-110 nm / min, and the deposition thickness was 1.0-2.0 μm.

7. The method for fabricating a Micro-LED light source as described in claim 5, characterized in that, The quantum dot solution filling the voids comprises: CdSe (cadmium selenide) and ZnS (zinc sulfide) red and green quantum dots were printed into the void region using an electric inkjet printing method.

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