Micro LED display and manufacturing method thereof

Abstract

Provided is a micro-LED display that does not use micro-LEDs of different types for each color and that has improved light emission efficiency, and a manufacturing method therefor. The micro-LED display is provided with a plurality of micro-UV-LED chips 1 and a wavelength conversion layer 32 in the form of a film that has phosphors 28R, 20G, 28B that respectively wavelength-convert ultraviolet light from the micro-UV-LED chips 1 into red, green, and blue light. The side surface of the micro-UV-LED chip 1 is formed as an inclined surface, and the micro-UV-LED chip 1 is surrounded by a reflection-blocking material 24 that reflects ultraviolet light emitted from the side surface.

Description

Technical Field

[0001] This invention relates to a micro LED display and its manufacturing method. Background Technology

[0002] In recent years, microLED displays have been anticipated as the next generation of displays for AR (Augmented Reality) or VR (Virtual Reality). However, due to the extremely small chip size of microLEDs (less than 100μm), it is difficult to achieve uniform luminous intensity within the wafer surface.

[0003] In Patent Document 1, a structure was disclosed to prevent light leakage from the image display element to adjacent pixels and to enhance the light output in the front direction of the image display element, thereby improving the luminous efficiency. The structure includes: micro-light-emitting elements arranged in an array, a drive circuit substrate including a drive circuit that supplies current to the micro-light-emitting elements to make them emit light, and a light distribution control unit (70) disposed on the light-emitting surface of the micro-light-emitting elements. An isolation wall that does not transmit light emitted by the micro-light-emitting elements is disposed around the light distribution control unit.

[0004] Existing technical documents Patent documents Patent document 1: Japanese Patent Application Publication No. 2021-144098. Summary of the Invention

[0005] The problem the invention aims to solve However, in micro LED displays with chip sizes below 100μm, the following problems exist: (1) Regarding miniaturized LED chips, when the chip size is below 50μm, the luminous efficiency of red LED chips using GaP-type materials will deteriorate sharply. (2) When GaP-type materials are used in red and InGaN-type materials are used in blue and green, the control becomes complicated due to the different driving voltage and current, and the electrical characteristics deviate, resulting in uneven color. (3) Installing red, green and blue micro LED chips by pick-and-place takes time and increases manufacturing costs.

[0006] The present invention was made in view of the above-mentioned problems, and its object is to provide a microLED display that improves luminous efficiency without using microLEDs of different types for each color, and a method thereof for manufacturing the same.

[0007] Solution for solving the problem This invention relates to a micro LED display, comprising: a first conductivity type electrode; a plurality of micro LEDs separately formed on the first conductivity type electrode, each emitting ultraviolet light with a wavelength below 405 nm; a second conductivity type electrode formed on the plurality of micro LEDs; a reflective blocking material vertically disposed between the plurality of micro LEDs to reflect light from the sides of the micro LEDs; a film-like wiring substrate having a wiring structure, which is connected to the second conductivity type electrode of the three micro LEDs such that three adjacent micro LEDs constitute one pixel; and a film-like wavelength conversion layer disposed on the wiring substrate, comprising phosphors that convert the wavelength of light from the three micro LEDs into red, green, and blue, respectively, wherein the sides of the micro LEDs are formed with inclined surfaces such that the width of the micro LEDs gradually narrows from the first conductivity type electrode to the second conductivity type electrode, and the reflective blocking material is parallel to the stacking direction of the plurality of micro LEDs and vertically disposed to the same height as the micro LEDs.

[0008] In one embodiment of the present invention, it further comprises: a resin in which phosphors are dispersed and filled between the microLED and the reflective blocking layer. In other embodiments of the present invention, the electrode of the first conductivity type is a copper-tungsten conductive substrate.

[0009] Furthermore, this invention provides a method for manufacturing a micro LED display, comprising: a step of crystallizing and growing a GaN buffer layer, an n-type layer, a light-emitting layer, and a p-type layer on a sapphire substrate in the order of crystallization; a step of depositing a transparent electrode on the p-type layer; a step of bonding a conductive substrate to the transparent electrode; a step of peeling the sapphire substrate and the GaN buffer layer; a step of forming a plurality of micro LEDs by etching from the n-type layer side and forming an inclined surface on the side of the micro LEDs; a step of depositing n electrodes on each of the plurality of micro LEDs; a step of forming a passivation layer on the portion of the plurality of micro LEDs other than the n electrodes; and a step of forming the plurality of micro LEDs... The process of forming a reflective blocking material vertically between D; the process of forming a film-like wiring substrate on the n-electrode such that three adjacent micro-LEDs among the plurality of micro-LEDs become one pixel; and the process of forming a film-like wavelength conversion layer with a phosphor on the wiring substrate, wherein the phosphor converts the wavelength of light from the three micro-LEDs into red, green, and blue, respectively, wherein the side of the micro-LED is formed with an inclined surface such that the width of the micro-LED gradually narrows from the conductive substrate to the n-type layer, and the reflective blocking material is parallel to the stacking direction of the plurality of micro-LEDs and is vertically arranged to the same height as the micro-LEDs.

[0010] In one embodiment of the present invention, a process of erecting a reflective blocking material between the plurality of micro-LEDs and a process of forming a film-like wiring substrate on the n-electrode in such a way that three adjacent micro-LEDs among the plurality of micro-LEDs become one pixel are simultaneously performed.

[0011] In other embodiments of the present invention, after the step of erecting and forming a reflective blocking material between the plurality of micro-LEDs, there is a step of filling a resin in which phosphors are dispersed between the micro-LEDs and the reflective blocking layer.

[0012] In yet another embodiment of the present invention, the conductive substrate is copper-tungsten.

[0013] Invention Effects According to the present invention, a microLED display and a method thereof are provided that improve luminous efficiency without using microLEDs of different types for each color. Attached Figure Description

[0014] Figure 1 This is a schematic cross-sectional view showing the basic structure of a micro-LED according to an embodiment. Figure 2A This is a schematic cross-sectional view of the micro LED display according to the implementation method. Figure 2B This is a schematic plan view of the micro LED display according to the implementation method. Figure 3 This is a schematic cross-sectional view (1) illustrating a method for manufacturing a micro LED display according to an embodiment. Figure 4 This is a schematic cross-sectional view (2) illustrating a method for manufacturing a micro LED display according to an embodiment. Figure 5 This is a schematic cross-sectional view (3) illustrating a method for manufacturing a micro LED display according to an embodiment. Figure 6 This is a schematic cross-sectional view (4) illustrating a method for manufacturing a micro LED display according to an embodiment. Figure 7 This is a schematic cross-sectional view (5) illustrating a method for manufacturing a micro LED display according to an embodiment. Figure 8 This is a schematic cross-sectional view (6) illustrating a method for manufacturing a micro LED display according to an embodiment. Figure 9 This is a schematic cross-sectional view (7) illustrating a method for manufacturing a micro LED display according to an embodiment. Figure 10This is a plan view of the film wiring substrate according to the embodiment. Figure 11 This is a schematic cross-sectional view (8) illustrating a method for manufacturing a micro LED display according to an embodiment. Figure 12 This is a schematic cross-sectional view showing a method for manufacturing a micro LED display according to a first modified example. Figure 13 This is a schematic cross-sectional view (1) showing a method for manufacturing a micro LED display of a second modified example. Figure 14 This is a schematic cross-sectional view (2) showing a method for manufacturing a micro LED display of a second variation. Detailed Implementation

[0015] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0016] Figure 1 A basic schematic cross-sectional view of the microLED used in the microLED display of this embodiment is shown.

[0017] The micro LED 1 is an LED whose chip size is a rectangular planar shape, with at least one side being 100 μm or less, more preferably 50 μm or less, and which emits ultraviolet light (UV) with a wavelength of 405 nm or less. The micro LED 1 in this embodiment is not a flip-chip structure with parallel electrode configuration, but a vertical V-chip structure with vertically positioned electrode configuration.

[0018] The micro LED 1 is constructed by sequentially stacking an ITO transparent electrode 12, a p-type layer 14, a light-emitting layer 16, an n-type layer 18, and an n-electrode 20 on a conductive substrate 10 of approximately 100 μm thickness, such as copper-tungsten (CuW). The substrate 10 corresponds to the electrode of the first conductivity type, and the n-electrode 20 corresponds to the electrode of the second conductivity type.

[0019] The p-type layer 14 is composed of a p-GaN (GaN; Mg) contact layer and a (AlGaN; Mg / GaN; Mg) p-SLS (superlattice structure) layer. That is, the p-GaN contact layer is formed on the heat-dissipating substrate 10 via a transparent electrode 12 of ITO.

[0020] The light-emitting layer 16 is composed of an (InGaN / AlGaN) MQW (multiple quantum well) layer.

[0021] The n-type layer 18 consists of a (AlInGaN) / (InGaN;Si)n-SLS (superlattice structure) layer and a (GaN;Si) contact layer.

[0022] Here, for example (GaN; Si) shows GaN doped with Si. The emission wavelength in this structure is specifically 385 nm, but it can also be, for example, 400 nm. Although the basic epitaxial structures of 385 nm and 400 nm are the same, due to the bandgap energy, the (InGaN / AlInGaN) MQW emitting layer 16 has a higher Al content and a lower In content compared to 400 nm.

[0023] Furthermore, the side surface of the micro-LED1 is formed with an inclined surface (conical shape) such that the width of the micro-LED1 gradually narrows relative to the stacking direction from the substrate 10 to the n-electrode 20, and a passivation layer 22 of SiO2 is formed on the side surface with the inclined surface. The angle of the inclined surface is arbitrary, but for example, from the viewpoint of maximizing the derived efficiency, 45 degrees is preferred.

[0024] In the micro-LED1, the side area ratio generally increases with miniaturization. However, in this embodiment, by using a V-chip structure instead of a flip-chip structure, the light extraction efficiency from the side is improved. Furthermore, by setting the shape of this side to an inclined surface, the area of ​​the side of the light-emitting layer 16 can be larger than that of a vertical side, further improving the light extraction efficiency from the side.

[0025] In addition, by using a substrate 10 with excellent heat dissipation properties, such as copper-tungsten, on the p-electrode side, heat dissipation can be improved, allowing for the application of a larger current, thus suppressing the decrease in luminous efficiency caused by heat generation.

[0026] Figure 2A It shows the use of Figure 1 A schematic cross-sectional view of a microLED display of a microLED 1 (hereinafter referred to as microUV-LED chip 1). Multiple (only 3 are shown in the figure) micro UV-LED chips 1 are formed separately on a common copper-tungsten (CuW) substrate 10. In addition, the multiple micro UV-LED chips 1 are arranged in a two-dimensional array on a plane.

[0027] A reflective barrier material 24 is erected between adjacent micro-UV-LED chips 1, parallel to the stacking direction of the micro-UV-LED chips 1, in other words, parallel to the normal direction of the surface of the substrate 10. The reflective barrier material 24 has the function of preventing light from adjacent micro-UV-LED chips 1 from leaking to other micro-UV-LED chips 1, and reflecting lateral light from the micro-UV-LED chips 1 to increase the light extraction efficiency in the light extraction direction (upper part in the figure). Therefore, it is made of a material such as aluminum that reflects light (ultraviolet light with wavelengths below 405 nm) from the sides of the micro-UV-LED chips 1. Furthermore, the height of the reflective barrier material 24 is the same as the height of the micro-UV-LED chips 1. Multiple micro-UV-LED chips 1 are surrounded and separated by reflective barrier materials 24.

[0028] Figure 2B A schematic plan view showing the positional relationship between the micro UV-LED chip 1 and the reflective blocking material 24 is shown. The reflective blocking material 24 is formed around the micro UV-LED chip 1, which has a rectangular planar shape. Furthermore, from... Figure 2A It can be seen that the reflective blocking material 24 is formed on the passivation layer 22 of SiO2. Since the micro UV-LED chip 1 is surrounded by the reflective blocking material 24, all the light emitted from the side of the light-emitting layer 16 is reflected by the reflective blocking material 24.

[0029] Back to Figure 2A A film-shaped wiring substrate 26 is formed on multiple micro UV-LED chips 1. Three n-type electrodes are formed on the film-shaped wiring substrate 26, each facing an n-electrode 20 of one of the three adjacent micro UV-LED chips 1, so that the film-shaped wiring substrate 26 is bonded to the n-electrodes 20 and the three n-type electrodes of the three adjacent micro UV-LED chips 1. Since the height of the reflective blocking material 24 is the same as the height of the micro UV-LED chips 1, the bonding of the film-shaped wiring substrate 26 is facilitated and homogenized. The wiring substrate 26 includes a driving circuit for driving the multiple micro UV-LED chips 1. The driving circuit includes a row selection circuit for selecting each row of the micro UV-LED chips 1 configured in a two-dimensional array, a column selection circuit for selecting each column, and an image processing circuit for generating a light emission signal based on an input signal.

[0030] On the film-like wiring substrate 26, R phosphor 28R, G phosphor 28G, and B phosphor 28B are further applied to form a film-like wavelength conversion layer 32 with high ultraviolet transmittance, comprising a blocking material 30 that separates these phosphors 28R, 28G, and 28B from each other. R phosphor 28R is configured, for example, as phosphor powder dispersed in a transparent resin curing material. This phosphor powder receives ultraviolet light from the micro UV-LED chip 1 and emits red light with a wavelength longer than that ultraviolet light. For example, LOS:Eu is used as the red phosphor powder. Additionally, for example, BAM:Eu,Mn is used as the green phosphor powder, and for example, BAM:Eu is used as the blue phosphor powder, but these are not limited to these. Here, LOS is La2O2S, and BAM is (Ba,Mg)Al. 10 O 17 .

[0031] exist Figure 2A In this pixel, an R phosphor 28R is disposed on the left-hand microUV-LED chip 1 among three adjacent microUV-LED chips 1, a G phosphor 28G is disposed on the central microUV-LED chip 1, and a B phosphor 28B is disposed on the right-hand microUV-LED chip 1. These three adjacent microUV-LED chips 1, along with phosphors 28R, 28G, and 28B, constitute one pixel. Ultraviolet light from the left-hand microUV-LED chip 1 is converted to a red wavelength by the R phosphor 28R and emitted outwards. Ultraviolet light from the central microUV-LED chip 1 is converted to a green wavelength by the G phosphor 28G and emitted outwards. Ultraviolet light from the right-hand microUV-LED chip 1 is converted to a blue wavelength by the B phosphor 28B and emitted outwards.

[0032] Furthermore, ultraviolet light emitted from the tilted side of the left-hand microUV-LED chip 1 out of the three adjacent microUV-LED chips 1 is reflected by a reflective blocking material 24 formed in a manner that surrounds the microUV-LED chip 1, and a portion of it is converted into a red wavelength by the R phosphor 28R and emitted outward. The same applies to the other microUV-LED chips 1.

[0033] Thus, in this embodiment, full color is obtained by exciting red, green, and blue phosphors with the same type of micro UV-LED chip 1, so mass transfer can be achieved through transfer printing instead of pick-and-place.

[0034] In addition, since the visible light component in the spectrum of the micro UV-LED chip 1 is weak, even if the characteristics of the UV-LED are assumed to be deviated, the effect on the emission color of the phosphor is small.

[0035] Furthermore, with the miniaturization of the micro UV-LED chip 1, the side area ratio increases relatively, thus improving the light extraction efficiency from the side by V-chip scaling. Moreover, this improvement in light extraction efficiency is further enhanced by the combined use of the inclined surface of the side of the micro UV-LED chip 1 and the reflective blocking material 24.

[0036] Furthermore, by using a copper-tungsten (CuW) substrate 10, heat dissipation characteristics are improved, allowing for the application of a larger driving current. Additionally, the reduction in luminous efficiency caused by heat generation during driving can be suppressed.

[0037] Next, the manufacturing method of the micro LED display according to this embodiment will be described.

[0038] Figures 3 to 11 This is a schematic cross-sectional view illustrating a method for manufacturing a micro LED display. First, as... Figure 3 As shown, an LED structure is formed on a sapphire substrate 30 by crystallization growth using metal-organic vapor deposition (MOCVD) in the order of GaN buffer layer 32, n-type layer 18, light-emitting layer 16, and p-type layer 14. Here, the n-type layer 18 includes an SLS (superlattice structure) layer, and the p-type layer 14 also includes an SLS layer. Furthermore, the light-emitting layer 16 includes an MQW (Multi-Layered Winding) layer of InGaN / AlGaN.

[0039] Then, a transparent ITO electrode 12 is formed by vapor deposition on the p-type layer, and a conductive substrate 10 with a thickness of about 100 μm, such as a copper tungsten (CuW) substrate 10, is bonded thereon.

[0040] Next, as Figure 4 As shown, after peeling off the sapphire substrate 30 and the GaN buffer layer 32, as Figure 5 As shown, multiple micro-LED chips with a size of 100 μm or less, more preferably 50 μm or less, are formed by isolating etching from the n-layer side. In this isolating etching process, the etching is performed in a manner that makes the side surface of the micro-LED chip an inclined surface (conical surface). The technique of forming an inclined surface by etching is known. The angle of the inclined surface, that is, the angle relative to the stacking direction of the micro-LED chip, is, for example, 45 degrees.

[0041] Next, as Figure 6 As shown, n electrodes 20 are formed by vapor deposition on the n-type layer surface of each of the isolated micro-LED chips.

[0042] Next, as Figure 7 As shown, a passivation layer 22 of SiO2 is formed in the region other than the n electrode 20 on the n-layer side of all micro LED chips to passivate them.

[0043] Next, as Figure 8 As shown, a reflective barrier material 24, made of a highly reflective material such as aluminum, is formed between adjacent micro-LED chips.

[0044] Next, as Figure 9 As shown, a film-shaped wiring substrate 26 having an n-type electrode 25 is bonded together in such a way that the n-electrodes 20 and n-type electrodes 25 of all the micro LED chips are joined together.

[0045] Figure 10 A partial plan view of the film-like wiring substrate 26 is shown. It represents the structure of one pixel corresponding to three adjacent micro-LED chips. Three n-type electrodes 25 are configured and connected to the driving circuit 27.

[0046] Then, as Figure 11 As shown, a film-like wavelength conversion layer 32, after being coated with R phosphor 28R, G phosphor 28G, and B phosphor 28B separated by a blocking material 30, is attached to a micro LED chip.

[0047] By manufacturing micro-LED displays through the processes described above, mass transfer can be achieved instead of pick-and-place, thus reducing the installation time. In other words, while manufacturing RGB or UV LED chips separately and using them as pixels to create a display requires the assembly of a large number of extremely small LEDs (less than 50μm) with high precision, this significantly reduces the time compared to picking up and assembling these LED chips individually.

[0048] Furthermore, since the sapphire substrate 30 and GaN buffer layer 32 are separated during manufacturing, there is no laser cutting process for the sapphire substrate 30. Therefore, damage to the LED chip sides due to heat generated by laser irradiation is avoided, preventing a decrease in luminous efficiency. In contrast, when using a flip-chip structure, red GaP-type LEDs are bonded to a sapphire substrate to ensure strength, and are cut using an excimer laser in the same way as green and blue InGaN-type LEDs, this cutting process causes significant heat-induced damage and blackening to the chip sides, reducing the chip's luminous efficiency. However, the manufacturing method of this embodiment prevents such heat-induced damage, avoiding a decrease in luminous efficiency.

[0049] In addition, by using a V-chip structure instead of an electrode configuration parallel flip-chip structure, the space required for n electrodes in the flip-chip is eliminated, thus increasing the number of chips that can be fabricated from the grown wafer (by about 2 times).

[0050] Furthermore, by forming an inclined surface on the side of the LED chip during the isolation etching process, the area of ​​the side of the light-emitting layer is increased. Combined with the reflective blocking material 24 that is vertically arranged parallel to the stacking direction of the LED chip, the light extraction efficiency from the lateral direction is improved.

[0051] <First Variation> In one embodiment, a reflective barrier material 24 is erected between the micro LED chips, and then a film-shaped wiring substrate 26 is bonded together. However, the film-shaped wiring substrate 26 with the reflective barrier material 24 can also be positioned such that the reflective barrier material 24 is located between the micro LED chips while bonding is being performed.

[0052] Figure 12 A cross-sectional view of the first modified example is shown. (As shown) Figure 7 As shown, after forming the SiO2 passivation layer 22, a film-shaped wiring substrate 26 having a reflective blocking material 24 formed according to the pixel size is attached in such a way that the reflective blocking material 24 is inserted between the micro LED chips, and the n-electrode 20 of each micro LED chip is bonded to the n-type electrode 25 of the wiring substrate 26.

[0053] According to this manufacturing method, since the wiring substrate 26 and the reflective blocking material 24 are integrated, the placement of the reflective blocking material 24 can be more firmly fixed, and the manufacturing process can be further simplified.

[0054] <Second Variation> In addition, in this embodiment, a reflective barrier material 24 is erected between the micro LED chips, and then a film-shaped wiring substrate 26 is bonded. However, after erecting the reflective barrier material 24, a silicon-based resin containing dispersed phosphors can be filled in the gap between the micro LED chips and the reflective barrier material 24, and then the film-shaped wiring substrate 26 can be bonded.

[0055] Figure 13 A cross-sectional view of the second modified example is shown. (As shown) Figure 8 As shown, after the reflective blocking material 24 is erected between the micro-LED chips, the gap between the micro-LED chips and the reflective blocking material 24 is filled with silicon-based resins 29R, 29G, and 29B in which phosphors are dispersed. Then, as... Figure 14 As shown, a film-like wiring substrate 26 is bonded.

[0056] Based on this structure, since the silicone resin containing dispersed phosphors is filled, it is not necessary to use... Figure 11 The phosphor is placed after the film-like wiring substrate 26 is bonded, which simplifies the process. Alternatively, the film-like wavelength conversion layer 32 can be bonded to the micro-LED chip after filling with silicone resin, if needed.

[0057] Explanation of reference numerals in the attached figures 1: Micro LED (micro UV-LED chip), 10: Substrate, 16: Light-emitting layer, 20: n electrode, 22: Passivation layer, 24: Reflective blocking material, 26: Wiring substrate, 28R: R (red) phosphor, 28G: G (green) phosphor, 28B: B (blue) phosphor, 30: Blocking material, 32: Wavelength conversion layer.

Claims

1. A miniature LED display, wherein, have: The electrode of the first conductivity type; Multiple micro LEDs are separately formed on the first conductive electrode, each emitting ultraviolet light with a wavelength below 405nm; The electrodes of the second conductivity type are respectively formed on the plurality of micro LEDs; A reflective blocking material is erected between the plurality of micro-LEDs to reflect light from the sides of the micro-LEDs; A film-like wiring substrate has a wiring structure that connects to the electrodes of the second conductivity type of the plurality of micro-LEDs in such a way that three adjacent micro-LEDs constitute one pixel; and A film-like wavelength conversion layer is disposed on the wiring substrate, and includes phosphors that convert the wavelengths of light from the three micro-LEDs into red, green, and blue, respectively. The side of the microLED is formed with an inclined surface such that the width of the microLED gradually narrows from the electrode of the first conductivity type to the electrode of the second conductivity type. The reflective blocking material is parallel to the stacking direction of the plurality of micro-LEDs and is vertically arranged at the same height as the micro-LEDs.

2. The micro LED display according to claim 1, wherein, It also has: A resin containing dispersed phosphors is filled between the microLED and the reflective blocking material.

3. A miniature LED display, wherein, have: The electrode of the first conductivity type; Multiple micro LEDs are separately formed on the first conductive electrode, each emitting ultraviolet light with a wavelength below 405nm; The electrodes of the second conductivity type are respectively formed on the plurality of micro LEDs; A reflective blocking material is erected between the plurality of micro-LEDs to reflect light from the sides of the micro-LEDs; A film-like wiring substrate has a wiring structure that connects to the electrodes of the second conductivity type of the plurality of micro-LEDs in such a way that three adjacent micro-LEDs constitute one pixel; and The resin is a resin containing dispersed phosphors that fills the space between the micro-LEDs and the reflective blocking material. The phosphors convert the wavelengths of light from the three micro-LEDs into red, green, and blue, respectively. The side of the microLED is formed with an inclined surface such that the width of the microLED gradually narrows from the electrode of the first conductivity type to the electrode of the second conductivity type. The reflective blocking material is parallel to the stacking direction of the plurality of micro-LEDs and is vertically arranged at the same height as the micro-LEDs.

4. The micro LED display according to any one of claims 1 to 3, wherein, The electrode of the first conductivity type is a copper-tungsten conductive substrate.

5. A method for manufacturing a micro LED display, wherein, have: The process of crystallizing and growing GaN buffer layer, n-type layer, light-emitting layer and p-type layer on sapphire substrate in sequence; The process of depositing a transparent electrode on the p-type layer by vapor deposition; The process of bonding a conductive substrate onto the transparent electrode; The process of peeling off the sapphire substrate and the GaN buffer layer; The process of forming multiple micro-LEDs by etching from the n-type layer side and forming inclined surfaces on the sides of the micro-LEDs; In the process of depositing n electrodes on the plurality of micro LEDs respectively; The process of forming a passivation layer on the portion of the plurality of micro-LEDs other than the n-electrode; The process of erecting and forming a reflective barrier material between the plurality of micro-LEDs; The process of forming a film-like wiring substrate on the n-electrode in such a way that three adjacent micro-LEDs of the plurality of micro-LEDs constitute one pixel; and In the process of forming a film-shaped wavelength conversion layer with phosphors on the wiring substrate, the phosphors convert the wavelengths of light from the three micro-LEDs into red, green, and blue, respectively. The side of the micro-LED is formed with an inclined surface such that the width of the micro-LED gradually narrows from the conductive substrate toward the n-type layer. The reflective blocking material is parallel to the stacking direction of the plurality of micro-LEDs and is vertically arranged at the same height as the micro-LEDs.

6. The method for manufacturing a micro LED display according to claim 5, wherein, Simultaneously, the process of erecting a reflective blocking material between the plurality of micro-LEDs and forming a film-like wiring substrate on the n-electrode in such a way that three adjacent micro-LEDs among the plurality of micro-LEDs become one pixel are performed.

7. The method for manufacturing a micro LED display according to claim 5, wherein, After the step of erecting and forming a reflective blocking material between the plurality of micro-LEDs, there is a further step of filling a resin in which phosphors are dispersed between the micro-LEDs and the reflective blocking material.

8. A method for manufacturing a micro LED display, wherein, have: The process of crystallizing and growing GaN buffer layer, n-type layer, light-emitting layer and p-type layer on sapphire substrate in sequence; The process of depositing a transparent electrode on the p-type layer by vapor deposition; The process of bonding a conductive substrate onto the transparent electrode; The process of peeling off the sapphire substrate and the GaN buffer layer; The process of forming multiple micro-LEDs by etching from the n-type layer side and forming inclined surfaces on the sides of the micro-LEDs; In the process of depositing n electrodes on the plurality of micro LEDs respectively; The process of forming a passivation layer on the portion of the plurality of micro-LEDs other than the n-electrode; The process of erecting and forming a reflective barrier material between the plurality of micro-LEDs; In the step of filling a resin in which phosphors are dispersed between the micro-LEDs and the reflective blocking material, the phosphors convert the wavelengths of light from the three micro-LEDs into red, green, and blue, respectively; and The process of forming a film-like wiring substrate on the n electrode in such a way that three adjacent micro-LEDs among the plurality of micro-LEDs become one pixel; The side of the micro-LED is formed with an inclined surface such that the width of the micro-LED gradually narrows from the conductive substrate toward the n-type layer. The reflective blocking material is parallel to the stacking direction of the plurality of micro-LEDs and is vertically arranged at the same height as the micro-LEDs.

9. The method for manufacturing a micro LED display according to any one of claims 5 to 8, wherein, The conductive substrate is copper-tungsten.

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