KR-20260065575-A - FULL-COLOR DIRECTIONAL LIGHT SOURCE, XR DEVICE COMPRISING THE SAME, AND METHOD FOR MANUFACTURING THE SAME

KR20260065575AKR 20260065575 AKR20260065575 AKR 20260065575AKR-20260065575-A

Abstract

The present invention provides a full-color linear light source element, an XR device including the same, and a method for manufacturing the same. A method for manufacturing a light-emitting element comprises: i) providing a thin-film LED structure including a single-crystal substrate, a multilayer semiconductor layer provided on the single-crystal substrate, an active layer provided on the multilayer semiconductor layer, and a p-type semiconductor layer provided on the active layer; ii) etching the active layer and the p-type semiconductor layer to provide a mesa-type LED structure on the multilayer semiconductor layer; iii) separating the multilayer semiconductor layer and the mesa-type LED structure from the single-crystal substrate; iv) etching the multilayer semiconductor layer to provide a plurality of nanorod arrays; v) providing an n-electrode between the plurality of nanorod arrays; vi) forming a black matrix layer between the plurality of nanorod arrays and filling the plurality of nanorod arrays with a gap filler; and vii) providing a red conversion layer and a green conversion layer corresponding to the plurality of nanorod arrays.

Inventors

홍영준
최영진
최중훈
김규영

Assignees

세종대학교산학협력단

Dates

Publication Date: 20260508
Application Date: 20251031
Priority Date: 20241031

Claims (17)

A step of providing a thin-film LED structure comprising a single-crystal substrate, a multilayer semiconductor layer provided on the single-crystal substrate, an active layer provided on the multilayer semiconductor layer, and a p-type semiconductor layer provided on the active layer. A step of etching the active layer and the p-type semiconductor layer to provide a mesa-type LED structure on the multilayer semiconductor layer, A step of separating the multilayer semiconductor layer and the mesa-type LED structure from the single-crystal substrate, The step of etching the above multilayer semiconductor layer to provide a plurality of nano-rod arrays, The step of providing n electrodes between the plurality of nanorod arrays, A step of forming a black matrix layer between the plurality of nanorod arrays and filling the plurality of nanorod arrays with a gap filler, and A step of providing a red conversion layer and a green conversion layer corresponding to the plurality of nanorod arrays above. A method for manufacturing a light-emitting device including
A step of providing a thin-film LED structure comprising a single-crystal substrate, a multilayer semiconductor layer provided on the single-crystal substrate, an active layer provided on the multilayer semiconductor layer, and a p-type semiconductor layer provided on the active layer. A step of separating the multilayer semiconductor layer, the active layer and the p-type semiconductor layer from the single-crystal substrate, The step of etching the above multilayer semiconductor layer to provide a plurality of nanorod arrays, The step of providing n electrodes between the plurality of nanorod arrays, A step of forming a black matrix layer between the plurality of nanorod arrays and filling the plurality of nanorod arrays with a gap filler, Step of providing a metal reflective layer on the gap filler, A step of providing a plurality of p-electrodes on the p-type semiconductor layer and providing a passivation layer between the plurality of p-electrodes, and A step of providing a red conversion layer and a green conversion layer corresponding to the plurality of p electrodes above. A method for manufacturing a light-emitting device including
A step of providing a thin-film LED structure comprising a single-crystal substrate, a multilayer semiconductor layer provided on the single-crystal substrate, an active layer provided on the multilayer semiconductor layer, and a p-type semiconductor layer provided on the active layer. A step of etching the active layer and the p-type semiconductor layer to provide a mesa-type LED structure on the multilayer semiconductor layer, A step of separating the multilayer semiconductor layer and the mesa-type LED structure from the single-crystal substrate, The step of etching the above multilayer semiconductor layer to provide a plurality of nanorod arrays, The step of providing n electrodes between the plurality of nanorod arrays, A step of forming a black matrix layer between the plurality of nanorod arrays and filling the plurality of nanorod arrays with a gap filler, Step of providing a metal reflective layer on the gap filler, A step of providing a plurality of p-electrodes on the p-type semiconductor layer and providing a passivation layer between the plurality of p-electrodes, and A step of providing a red conversion layer and a green conversion layer corresponding to the plurality of p electrodes above. A method for manufacturing a light-emitting device including
In any one of paragraphs 1 through 3, In the step of providing the above thin-film LED structure, The above multilayer semiconductor layer is, An intrinsic semiconductor layer comprising GaN, provided on the above single-crystal substrate, and An n-type semiconductor layer comprising n-GaN provided on the intrinsic semiconductor layer above. A method for manufacturing a light-emitting device including
In Paragraph 4, In the step of providing the plurality of nanorod arrays, The above plurality of nanorod arrays is a method for manufacturing a light-emitting device comprising the n-type semiconductor layer and the intrinsic semiconductor layer.
In any one of paragraphs 1 through 3, A method for manufacturing a light-emitting device in which the active layer is a quantum well layer in which an InGaN layer and a GaN layer are grown alternately, and the InGaN layer is formed as In y Ga 1-y N (0.1<y<x<0.5).
In paragraph 1 or 3, The step of providing the above-mentioned mesa-type LED structure is: A step of providing a p-electrode on the above p-type semiconductor layer, A step of providing a passivation layer covering a plurality of mutually spaced micro LEDs included in the above mesa-type LED structure, A step of removing a passivation layer provided on the p-electrode among the passivation layers to expose the p-electrode, and Step of covering the passivation layer and the p-electrode with a metal reflective layer A method for manufacturing a light-emitting device including
In Paragraph 7, Before the step of providing the above passivation layer, A method for manufacturing a light-emitting device by pretreating the above active layer by contacting it with one or more compounds selected from the group consisting of KOH, NaOH, TMAH, H₃PO₄ , and H₂SO₄ at 40°C to 120°C for 5 to 30 minutes.
In paragraph 1, In the step of providing the above red conversion layer and green conversion layer, A method for manufacturing a light-emitting device in which the plurality of nanorod arrays include a first nano array, a second nano array, and a third nano array adjacent to each other, the red conversion layer is provided on the first nano array, the green conversion layer is provided on the second nano array, and the third nano array is formed hollow.
In paragraph 2 or 3, In the step of providing the above red conversion layer and green conversion layer, A method for manufacturing a light-emitting device in which the plurality of p-electrodes include a first p-electrode, a second p-electrode, and a third p-electrode adjacent to each other, the red conversion layer is provided on the first p-electrode, the green conversion layer is provided on the second p-electrode, and the third p-electrode is formed hollow.
A mesa-type LED structure comprising a plurality of mutually spaced micro LEDs, An intrinsic semiconductor layer provided on the above mesa-type LED structure, A passivation layer provided below the intrinsic semiconductor layer while covering the sides of the plurality of micro LEDs, p-electrode provided below the plurality of micro LEDs above, The above passivation layer and the metal reflective layer covering the p-electrode, A plurality of mutually spaced nanorod arrays provided on the intrinsic semiconductor layer above, n electrode provided on the intrinsic semiconductor layer and located between the plurality of nanorod arrays, A black matrix layer formed between the above plurality of nanorod arrays, A gap filler filled in the plurality of nanorod arrays and covering the black matrix layer, and Red conversion layer and green conversion layer provided corresponding to the plurality of nanorod arrays above A light-emitting element including
Thin film LED structure, An intrinsic semiconductor layer provided on the above thin-film LED structure, A plurality of p-electrodes spaced apart from each other and provided below the above thin-film LED structures, A plurality of mutually spaced nanorod arrays provided on the intrinsic semiconductor layer above, n electrode provided on the intrinsic semiconductor layer and located between the plurality of nanorod arrays, A black matrix layer formed between the above plurality of nanorod arrays, A gap filler that fills the plurality of nanorod arrays and covers the black matrix layer, A metal reflective layer covering the gap filler, A red conversion layer and a green conversion layer provided below the plurality of p electrodes, and A passivation layer provided below the thin-film LED structure between a plurality of p-electrodes A light-emitting element including
A mesa-type LED structure comprising a plurality of mutually spaced micro LEDs, An intrinsic semiconductor layer provided on the above mesa-type LED structure, A passivation layer provided below the intrinsic semiconductor layer while covering the sides of the plurality of micro LEDs, A plurality of p-electrodes each provided below the plurality of micro LEDs above, A plurality of mutually spaced nanorod arrays provided on the intrinsic semiconductor layer above, n electrode provided on the intrinsic semiconductor layer and located between the plurality of nanorod arrays, A black matrix layer formed between the above plurality of nanorod arrays, A gap filler that fills the plurality of nanorod arrays and covers the black matrix layer, A metal reflective layer covering the gap filler, and Red conversion layer and green conversion layer provided below the plurality of p electrodes A light-emitting element including
In any one of paragraphs 11 through 13, The above active layer is a quantum well layer in which an InGaN layer and a GaN layer are grown alternately, the above InGaN layer is formed as In y Ga 1-y N (0.1<y<x<0.5), and the above active layer is a light-emitting device applied to emit blue light having a wavelength of 400nm to 500nm.
In any one of paragraphs 11 through 13, The lower portion of the plurality of nanorod arrays is formed integrally with the intrinsic semiconductor layer, and the upper portion of the plurality of nanorod arrays in contact with the lower portion is formed as an n-type semiconductor layer. A light-emitting device in which the intrinsic semiconductor layer comprises GaN and the n-type semiconductor layer comprises n-GaN.
In Paragraph 15, It further includes a superlattice layer located between the active layer and the intrinsic semiconductor layer, and The above superlattice layer is a light-emitting device formed by growing InGaN and GaN layers alternately.
An XR device comprising a light-emitting element according to any one of claims 11 to 13, and displaying a display screen by said light-emitting element.

Description

Full-color directional light source element, XR device comprising the same, and method for manufacturing the same The present invention relates to a light source element, an XR device including the same, and a method for manufacturing the same. More specifically, the present invention relates to a full-color linear light source element of blue/green/red having high linearity and efficiency, an XR device including the same, and a method for manufacturing the same. In next-generation near-eye XR (extended reality) devices, significant light loss occurs not only in waveguides but also in diffractive optical systems; therefore, the luminance of the light source pixels before entering the optical system must be very high. The final light reaching the eye requires a luminance of at least 2,000 nits, and hundreds of thousands of nits are required at the pixel level to ensure a wide field of view and multi-focal range necessary to blur the distinction between the virtual and the real world. The size of XR microdisplays should preferably be 0.5 inches or smaller, and for 4K-level displays, pixel sizes of up to 3 x 3 µm² must be secured. Furthermore, to achieve vivid image quality, color purity compliant with REC.2020 standards must be secured, requiring technology that minimizes not only the center wavelength but also the Full Width at Half Maximum (FWHM). While technologies such as LCoS (liquid crystal on Si) or OLEDoS (organic light emitting diode on Si) are being developed for XR projector displays, they do not satisfy the light source standards—primarily luminance standards—necessitated for use in outdoor AR projectors. Inorganic semiconductor-based micro LEDs appear to be the most promising alternative for XR displays due to their superior brightness characteristics. However, in the case of inorganic micro LEDs, the efficiency of green and red is very low compared to blue, and in particular, the efficiency of red decreases sharply as the size is reduced. When light propagates through an array of particles with a constant spacing and shape, optical interference occurs. In this case, if the particle size, shape, spacing, and the refractive indices of the particles and the medium constituting the array satisfy the conditions for constructive interference with the wavelength of the propagated light, a photonic crystal effect is exhibited. Thus, the photonic crystal effect refers to an optical interference phenomenon in which light of a specific wavelength is trapped or reflected within an array of materials having a periodic structure. If light propagated in a photonic crystal scatters and causes superposition interference only at specific lattice points, it selectively causes total internal reflection of light at a specific wavelength; this light is then amplified through the superposition of optical confinement modes, enabling lasing oscillation through stimulated luminescence. Therefore, to achieve lasing oscillation through the photonic crystal effect, the conditions for forming an optical bandgap wavelength must be satisfied by controlling the particle size and lattice spacing of the crystal. Conventionally, to manufacture highly directional nanorod LED arrays based on the photonic crystal effect, bottom-up methods based on semiconductor material growth and top-down methods based on semiconductor material etching processes have been used. However, in the bottom-up method, it is very difficult to ensure uniformity in the size and shape of nanorod LEDs at the level of hundreds of nanometers. Furthermore, since the emissive layer is formed in a core-shell structure, it is difficult to manufacture light sources with high color purity. On the other hand, while the top-down method may be superior in terms of uniformity, the efficiency of the light-emitting device is significantly reduced because the emissive layer is damaged by plasma during the etching process. Therefore, in the bottom-up method, it is very difficult to expect the photonic crystal effect due to uniformity issues, and in the top-down method, even if a highly directional nanorod array light source utilizing the photonic crystal effect is manufactured, it is difficult to satisfy the high performance requirements of actual XR devices. FIG. 1 is a schematic perspective view of an XR device including a light-emitting element according to a first embodiment of the present invention. Figure 2 is a schematic flowchart of the manufacturing method of the light-emitting element of Figure 1. FIGS. 3 to 9 are schematic cross-sectional views of light-emitting elements manufactured at each step of the method for manufacturing a light-emitting element of FIG. 2. FIGS. 10 and FIGS. 11 are, respectively, a flowchart of a schematic method for manufacturing a light-emitting element according to a second embodiment of the present invention and a schematic cross-sectional view of a light-emitting element manufactured using the same. FIGS. 12 and FIGS. 13 are, respectivel