Micro-LED light source and preparation method thereof

Abstract

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

Description

Technical Field

[0001] The present invention relates to the field of semiconductor display technology, and in particular to a Micro-LED light source and a preparation method thereof. Background Art

[0002] At present, the vast majority of full-color Micro-LED-based display products on the market use color conversion technology. In this regard, semiconductor quantum dots (Quantum Dots, QD) stand out with their excellent optical and physical properties, including quantum yields of more than 90%, adjustable emission wavelengths, large relative surface areas, narrow emission spectra, high light stability and good solution processability, making them the mainstream materials for color conversion. These characteristics not only provide a reliable path to achieve 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-LED to activate quantum dots has raised concerns about blue light leakage, optical crosstalk and reduced brightness. The color conversion scheme in full-color Micro-LED display technology usually requires the use of filters to eliminate the inevitable blue light leakage during the color conversion process. This method leads to a certain loss of light energy and increases the complexity and cost of the production process. Some recent studies have achieved significant improvements by using high-concentration quantum dot films, but the thickness of the quantum dot film brings new challenges, such as low color conversion efficiency, crosstalk problems and difficulty in manufacturing thick films.

[0004] Therefore, technicians in this field are committed to developing a full-color display Micro-LED light source and a preparation method thereof that can effectively reduce blue light leakage while achieving high efficiency and high brightness. Summary of the invention

[0005] In view of the above-mentioned defects 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 and a preparation method thereof that effectively reduces blue light leakage and achieves high efficiency and high brightness.

[0006] To achieve the above objectives, the present invention provides a Micro-LED light source and a method for preparing the same, which enhances the color conversion effect by filling the gaps of the LED with a quantum dot solution; deposits the quantum dots into the hollow part of the device to avoid the transfer step of the quantum dot layer and minimizes the crosstalk problem caused by bottom emission.

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

[0008] substrate layer;

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

[0010] A first n-type GaN layer is located on a surface of the buffer layer facing away from the substrate layer;

[0011] A plurality of hollow cylindrical structures are located on a surface of the first n-type GaN layer facing away from the buffer layer, wherein the hollow cylindrical structure includes a table structure, a passivation layer partially wrapping the table 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; the gap is used to fill the quantum dot solution.

[0012] Preferably, the table structure comprises:

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

[0014] a third n-type GaN layer, located on a surface of the second n-type GaN layer facing away from the first n-type GaN layer;

[0015] A second multi-quantum well structure layer is located on a surface of the third n-type GaN layer facing away from the second n-type GaN layer;

[0016] A second p-type GaN layer is located on a surface of the second multi-quantum well structure layer facing away from the third n-type GaN layer;

[0017] The current diffusion layer is located on a surface of the second p-type GaN layer that is away from the second multi-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 successively; the widths of the third n-type GaN layer, the second multi-quantum well structure layer, the second p-type GaN layer and the current diffusion layer are consistent.

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

[0020] Preferably, scattering particles filling the gaps are also included.

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

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

[0023] providing a substrate layer;

[0024] forming a buffer layer on a surface of one side of the substrate layer;

[0025] forming a first n-type GaN layer on a surface of the buffer layer facing away from the substrate layer;

[0026] A plurality of hollow cylindrical structures are formed on a surface of the first n-type GaN layer facing away from the buffer layer; the hollow cylindrical structure includes a table structure, a passivation layer partially wrapping the table 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; the gap is used to fill a quantum dot solution.

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

[0028] Forming a first multi-quantum well structure layer by alternately growing InGaN or AlGaN quantum well layers and GaN quantum barrier layers of different compositions and thicknesses on a surface of the first n-type GaN layer away from the buffer layer;

[0029] Growing a first p-type GaN layer on a surface of the first multi-quantum well structure layer facing away from the first n-type GaN layer;

[0030] Performing laser lithography from the first p-type GaN layer to the first n-type GaN layer using a maskless aligner, and etching two steps using inductively coupled plasma to form a second n-type GaN layer, a third n-type GaN layer, and a second multi-quantum well structure layer and a second p-type GaN layer having the same width as the third n-type GaN layer;

[0031] Growing a current diffusion layer on a surface of the second p-type GaN layer on a side away from the second multi-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 a gap is formed between the passivation layer and a surface of one side of the first n-type GaN layer.

[0033] Preferably, the growth method of the passivation layer includes:

[0034] A passivation layer is deposited on the surface of the mesa structure by plasma enhanced chemical vapor deposition; the deposition temperature is 290-310°C, 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.

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

[0036] The beneficial effects of the present invention are as follows: the present invention enhances the color conversion effect by filling the hollow part of the LED with quantum dot solution. The quantum dots are directly deposited into the hollow part of the device by inkjet printing technology, avoiding the transfer step of the quantum dot layer and minimizing the crosstalk problem caused by bottom emission. The current diffusion layer is covered on the surface of the mesa structure, and the emission angle is controlled by adjusting the thickness of the passivation layer. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

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

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

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

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

[0043] Figure 7 is a flow chart of a method for preparing a Micro-LED light source in some embodiments of the present invention;

[0044] Figure 8 is a comparison chart of color conversion spectra of some embodiments of the present invention and traditional quantum dot films;

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

[0046] Fig.10 2 is a light emitting angle distribution diagram of some embodiments of the present invention. DETAILED DESCRIPTION

[0047] The present invention is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that in the description of the present invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific manner, and therefore cannot be understood as limiting the present invention. The terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0048] In addition, 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] The embodiments of the present application provide a Micro-LED light source and a method for preparing a Micro-LED light source. The following are detailed descriptions of each. It should be noted that the description order of the following embodiments is not intended to limit the preferred order of the embodiments.

[0050] like Figure 1 As shown, Figure 1 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, located on one side surface of the substrate layer 11;

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

[0054] A plurality of hollow cylindrical structures are located on a surface of the first n-type GaN layer 31 facing away from the buffer layer 21, wherein the hollow cylindrical structure includes a table structure, a passivation layer 71 partially wrapping the table structure, a reflective electrode layer 91 partially wrapping the passivation layer 71, and a gap 81 formed by the passivation layer not wrapped by the reflective electrode layer 91 and the first n-type GaN layer 31; the gap 81 is used to fill the quantum dot solution.

[0055] In the embodiment of the present application, a reflective electrode layer 91 is covered on the surface of the mesa structure, and combined with the thickness adjustment of the passivation layer 71, the emission angle can be controlled; by filling the gaps 81 formed in the mesa structure with a quantum dot solution, the color conversion effect can be enhanced; this method does not require the quantum dot layer to be transferred to the Micro-LED surface, and effectively reduces blue light leakage, while achieving an efficient, high-brightness full-color display effect.

[0056] The following will be combined Figure 1-Figure 6The structure of the present application will be described in detail.

[0057] In the embodiment of the present application, the table structure includes:

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

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

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

[0061] A second p-type GaN layer 52 is located on a surface of the second multi-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 a surface of the second p-type GaN layer 52 that is away from the second multi-quantum well structure layer 42 .

[0063] In the embodiment of the present 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 successively to form a step-like structure; the widths of the third n-type GaN layer 33, the second multi-quantum well structure layer 42, the second p-type GaN layer 52 and the current diffusion layer 61 are consistent.

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

[0065] In some preferred embodiments of the present invention, scattering particles filling the gaps are also included. The role of scattering particles in LEDs is mainly to enhance the scattering and absorption of light. When blue light is irradiated onto the scattering particles, the particles will scatter the light in all 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, so that more blue light can be absorbed by 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 the scattering and absorption of light, but also makes the distribution of quantum dots in the LED more uniform. This helps to improve the uniformity and color purity of the light emission of the LED. At the same time, scattering particles can also reduce the direct leakage of blue light in the LED, thereby improving the color conversion efficiency.

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

[0067] 101. Provide a substrate layer;

[0068] 102. Forming a buffer layer on a surface of one side of the substrate layer;

[0069] 103. Forming a first n-type GaN layer on a surface of the buffer layer facing away from the substrate layer;

[0070] 104. A plurality of hollow cylindrical structures are formed on a surface of the first n-type GaN layer facing away from the buffer layer; the hollow cylindrical structure includes a table structure, a passivation layer partially wrapping the table 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; the gap is used to fill the quantum dot solution.

[0071] In some embodiments of the present application, after providing the substrate layer in step 101, a standard cleaning method may be used to clean the exposed epitaxial wafer. In some embodiments of the present application, forming a plurality of hollow cylindrical structures on a surface of the first n-type GaN layer facing away from the buffer layer comprises:

[0072] Forming a first multi-quantum well structure layer by alternately growing InGaN or AlGaN quantum well layers and GaN quantum barrier layers of different compositions and thicknesses on a surface of the first n-type GaN layer away from the buffer layer;

[0073] Growing a first p-type GaN layer on a surface of the first multi-quantum well structure layer facing away from the first n-type GaN layer;

[0074] In some embodiments of the present application, the following may be formed: Figure 2 The hierarchical 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 away from 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 away from 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 away from the first n-type GaN layer 31.

[0075] Laser lithography is performed from the first p-type GaN layer to the first n-type GaN layer using a maskless aligner, and two steps are etched using inductively coupled plasma to form a second n-type GaN layer, a third n-type GaN layer, and a second multi-quantum well structure layer and a second p-type GaN layer having the same width as the third n-type GaN layer; in some embodiments of the present 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 away from the substrate layer 11; a second n-type GaN layer 32, located on the side surface of the first n-type GaN layer 31 away from the buffer layer 21; a third n-type GaN layer 33, located on the side surface of the second n-type GaN layer 32 away from the first n-type GaN layer 31; a second multi-quantum well structure layer 42, located on the side surface of the third n-type GaN layer 33 away from the second n-type GaN layer 32; and a second p-type GaN layer 52, located on the side surface of the second multi-quantum well structure layer 42 away from the third n-type GaN layer 33.

[0076] Growing a current diffusion layer on a surface of the second p-type GaN layer on a side away from the second multi-quantum well structure layer;

[0077] In some embodiments of the present application, the following may 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 away from the substrate layer 11; a second n-type GaN layer 32, located on the side surface of the first n-type GaN layer 31 away from the buffer layer 21; a third n-type GaN layer 33, located on the side surface of the second n-type GaN layer 32 away from the first n-type GaN layer 31; a second multi-quantum well structure layer 42, located on the side surface of the third n-type GaN layer 33 away from the second n-type GaN layer 32; a second p-type GaN layer 52, located on the side surface of the second multi-quantum well structure layer 42 away from 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 away from the second multi-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 a gap is formed between the passivation layer and a surface of one side of the first n-type GaN layer.

[0079] In some embodiments of the present application, the following may 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 one side surface of the buffer layer 21 away from the substrate layer 11; a second n-type GaN layer 32, located on one side surface of the first n-type GaN layer 31 away from the buffer layer 21; a third n-type GaN layer 33, located on one side surface of the second n-type GaN layer 32 away from the first n-type GaN layer 31; a second multi-quantum well structure layer 42, located on one side surface of the third n-type GaN layer 33 away from the second n-type GaN layer 32; a second p-type GaN layer 52, located on one side surface of the second multi-quantum well structure layer 42 away from the third n-type GaN layer 33; a current diffusion layer 61, located on one side surface of the second p-type GaN layer 52 away from the second multi-quantum well structure layer 42; and a passivation layer 71 partially wrapping the mesa structure, and a gap 81 formed by the passivation layer 71 and the first n-type GaN layer 31.

[0080] It should be noted that the present invention does not impose any specific limitation on the depth and diameter of the void 81, ie, the hollow cylinder. In some embodiments of the present application, Ni / Au (5 / 5 nm) is deposited by electron beam evaporation and then photolithography is performed to form a current diffusion layer.

[0081] In some embodiments of the present application, rapid thermal treatment is performed at 570°C 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 contact, the contact resistance is very small and almost negligible, so the current can smoothly pass through the contact interface; the contact resistance can be reduced by the p-type ohmic contact.

[0082] The growth methods of the passivation layer 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°C, 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, it can be 1.5μm.

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

[0085] The CdSe cadmium selenide / ZnS zinc sulfide red quantum dots and green quantum dots are printed into the gap region by using an electric inkjet printing method.

[0086] In the embodiment of the present application, Ti / Al / Ti / Au (20 / 150 / 50 / 100nm) is deposited as a reflective electrode layer by electron beam evaporation. Since the reflective metal layer is covered on the outside of the mesa structure and the thickness of the passivation layer is adjusted, the emission angle can be controlled. This method can transform the traditional vertical surface emission into horizontal emission, significantly reduce blue light leakage, and optimize the interaction between light and quantum dots.

[0087] The Micro-LED light source structure provided in this embodiment, first, the hollow cylindrical structure realizes 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 a peripheral reflective electrode. This design converts the traditional vertical surface emission into a horizontal emission, significantly reduces blue light leakage, and optimizes the interaction between light and quantum dots. By filling the hollow part of the LED with a quantum dot solution and combining it with the addition of scattering particles, the absorption and color conversion efficiency of blue light are enhanced. Experiments show that the present invention has obvious advantages in reducing blue light leakage, improving conversion efficiency, and achieving high-brightness output. In addition, by directly depositing quantum dots in the hollow area through inkjet printing technology, the manufacturing process is simplified, the deposition accuracy and uniformity of quantum dots are improved, and high-performance full-color display is achieved.

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

[0089] Fig. 9 By showing the relationship between brightness and current density, the present invention reveals that after integrating quantum dots with hollow cylinder diameters of 50 and 100 μm, the brightness performance of green light (corresponding to HC-50-GQD and HC-100-GQD) and red light (corresponding to HC-50-RQD and HC-100-RQD) arrays has been significantly improved. In particular, in the HC-100 array, taking a 10×10 quantum dot array as an example, the introduction of quantum dots not only achieves a significant increase in green light brightness, reaching 37A / cm 2The high brightness level of over 10Knits under current density, and the red light brightness also reached 9600nits, which significantly surpassed the record of red and green light brightness of traditional quantum dot color conversion technology. Similarly, the HC-50 array also showed excellent performance, that is, the brightness exceeded 8000nits under the same current density.

[0090] The luminous intensity distribution of the traditional square Micro-LED (Rec-100) follows the typical Lambertian emission model, which means that its luminous intensity is mainly concentrated in the center and gradually weakens toward the edge. The overall luminous angle is about 120°. In comparison, the Micro-LED light source of the present invention exhibits a wider light divergence angle due to its unique hollow cylindrical structure design. This ultra-large divergence angle mainly comes from the design of the structure. First, the reflective electrodes on the upper surface and the periphery effectively reflect the outwardly emitted light into the hollow center. After the light passes through the hollow structure, it will also experience multiple internal scattering or reflections, and finally escape from the hollow and be recorded by the detector. This multiple internal scattering or reflection of light means that part of the light energy is consumed in the form of heat energy in the hollow, but it is worth noting that this is the case without quantum dots. However, when quantum dots containing scattering particles are introduced, the situation will be different. The participation of quantum dots will further enhance the scattering effect of light, and can also realize the conversion of light of specific wavelengths, making it possible to achieve high-efficiency and high-uniformity full-color display.

[0091] like Fig.10 As shown in the figure, the luminous angle distribution diagrams of HC-50 and HC-100 devices reveal the highly concentrated characteristics of light. Among them, HC-50 is mainly concentrated in the range of -75° to -55° and +55° to +75°, while the luminous intensity distribution of HC-100 is more concentrated, with the distribution area mainly located between -75° and -65° and +65° and +75°. This highly concentrated luminous characteristic in the lateral direction is particularly beneficial to the color conversion of quantum dots, because the lateral concentrated divergence angle effectively limits the light in the hollow area and effectively prolongs the path length of the light interacting with the quantum dot material in the hollow area, thereby enhancing the effect of color conversion. In particular, the structural design of HC-Micro-LEDs forces the light to escape the hollow structure after multiple internal scattering or reflection, which not only increases the probability of light interacting with quantum dots, but also helps to achieve more uniform light output. In contrast, the Lambertian model luminous distribution of traditional planar Micro-LEDs is mainly emitted from the top surface, which leads to blue light leakage and light crosstalk problems.

[0092] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A Micro-LED light source, characterized in that: include: substrate layer; A buffer layer, located on one side surface of the substrate layer; A first n-type GaN layer is located on a surface of the buffer layer facing away from the substrate layer; A plurality of hollow cylindrical structures are located on a surface of the first n-type GaN layer facing away from the buffer layer, wherein the hollow cylindrical structure includes a table structure, a passivation layer partially wrapping the table 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; the gap is used to fill the quantum dot solution.

2. The Micro-LED light source according to claim 1, wherein: The table structure comprises: A second n-type GaN layer is located on a surface of the first n-type GaN layer facing away from the buffer layer; a third n-type GaN layer, located on a surface of the second n-type GaN layer facing away from the first n-type GaN layer; A second multi-quantum well structure layer is located on a surface of the third n-type GaN layer facing away from the second n-type GaN layer; A second p-type GaN layer is located on a surface of the second multi-quantum well structure layer facing away from the third n-type GaN layer; The current diffusion layer is located on a surface of the second p-type GaN layer that is away from the second multi-quantum well structure layer.

3. The Micro-LED light source according to claim 2, wherein: The widths of the first n-type GaN layer, the second n-type GaN layer and the third n-type GaN layer decrease in sequence; the widths of the third n-type GaN layer, the second multi-quantum well structure layer, the second p-type GaN layer and the current diffusion layer are consistent.

4. The Micro-LED light source according to claim 1, wherein: The quantum dot solution comprises CdSe cadmium selenide / ZnS zinc sulfide red quantum dots and green quantum dots.

5. The Micro-LED light source according to claim 1 or 4, characterized in that: Also included are scattering particles filling the gaps.

6. The Micro-LED light source according to claim 1, wherein: The thickness of the passivation layer is in the range of 1.0-2.0 μm.

7. A method for preparing a Micro-LED light source, characterized in that: include: providing a substrate layer; forming a buffer layer on a surface of one side of the substrate layer; forming a first n-type GaN layer on a surface of the buffer layer facing away from the substrate layer; A plurality of hollow cylindrical structures are formed on a surface of the first n-type GaN layer facing away from the buffer layer; the hollow cylindrical structure includes a table structure, a passivation layer partially wrapping the table 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; the gap is used to fill a quantum dot solution.

8. The method for preparing a Micro-LED light source according to claim 7, wherein The plurality of hollow cylindrical structures formed on the surface of the first n-type GaN layer facing away from the buffer layer include: Forming a first multi-quantum well structure layer by alternately growing InGaN or AlGaN quantum well layers and GaN quantum barrier layers of different compositions and thicknesses on a surface of the first n-type GaN layer away from the buffer layer; Growing a first p-type GaN layer on a surface of the first multi-quantum well structure layer facing away from the first n-type GaN layer; Performing laser lithography from the first p-type GaN layer to the first n-type GaN layer using a maskless aligner, and etching two steps using inductively coupled plasma to form a second n-type GaN layer, a third n-type GaN layer, and a second multi-quantum well structure layer and a second p-type GaN layer having the same width as the third n-type GaN layer; Growing a current diffusion layer on a surface of the second p-type GaN layer on a side away from the second multi-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 a gap is formed between the passivation layer and a surface of one side of the first n-type GaN layer.

9. The method for preparing a Micro-LED light source according to claim 8, wherein: The growth methods of the passivation layer include: A passivation layer is deposited on the surface of the mesa structure by plasma enhanced chemical vapor deposition; the deposition temperature is 290-310°C, 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.

10. The method for preparing a Micro-LED light source according to claim 7, wherein: The quantum dot solution filling the gaps comprises: The CdSe cadmium selenide / ZnS zinc sulfide red quantum dots and green quantum dots are printed into the gap region by using an electric inkjet printing method.

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