A light-conversion full-color Micro LED chip and its fabrication method

Abstract

This application discloses a light-conversion full-color Micro LED chip and its fabrication method, including a transparent support substrate, a transparent adhesion layer, a transparent insulating protective layer, a light conversion layer, a ring-shaped light blocking layer, an epitaxial structure, a transparent conductive layer, ohmic contact electrodes, an insulating reflective layer, wiring lines, an insulating layer, and bonding electrodes. This application, through the redesign and corresponding structural layout of the Micro LED chip, and by providing corresponding fabrication processes and methods, effectively solves the problem of light crosstalk in color conversion in existing technologies. The packaging design effectively improves the quality of the light excited by the color conversion layer, prevents light crosstalk, greatly enhances product reliability, increases production efficiency, meets enterprise production needs, and improves enterprise competitiveness.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, specifically to a light-converting full-color Micro LED chip and its fabrication method. Background Technology

[0002] Compared with existing OLED technology, the new generation of display technology, micro LED, not only has the characteristics of high luminous efficiency, high brightness and low power consumption, but is also less affected by water vapor, oxygen or high temperature. Therefore, it has obvious advantages in terms of stability, service life and operating temperature.

[0003] Currently, the technical solutions for full-color Micro LED displays are mainly divided into two categories: (1) Using Micro LED chips with three different light emission wavelengths (red, green, and blue) to arrange into a pixel array to achieve full-color display. This requires at least three mass transfers to complete the arrangement of Micro LED chips from three different epitaxial wafers (red, green, and blue). Improving the yield and production efficiency of mass transfer is the key problem that this technical solution needs to solve; (2) Using blue or near-ultraviolet Micro LED chips to arrange into an array, and then coating the surface of the Micro LED chip corresponding to the corresponding pixel with fluorescent material according to the arrangement of red, green, and blue pixels. Through wavelength conversion of the fluorescent material, the pixels of the three primary colors (red, green, and blue) are realized.

[0004] In the prior art, the patent "System and Method for Multicolor LEDs with Stacked Bonding Structures" proposes to vertically stack R, G, and B color chips through bonding to achieve full-color display; the patent "A Micro LED Chip for Full-Color Display" provides a Micro LED chip for full-color display, forming a red, blue, and green light-emitting structure on a single LED chip, which eliminates the need for RGB arrays and microlenses, allowing a single Micro LED chip to achieve full-color light emission; the patent "A Micro LED Full-Color Display Device and Fabrication Method Based on Microfluidic Technology" discloses a Micro LED full-color display device structure and fabrication method based on microfluidic technology, using a thinned Micro LED chip array substrate as the substrate, etching pits corresponding to the Micro LED units on the substrate, pressing a microfluidic cover plate onto the substrate to directly fabricate the microfluidic chip on the substrate, and then injecting quantum dot solution into the pits of the substrate to form a color conversion layer, thereby achieving full-color display; the patent "A Full-Color Micro LED Chip for Full-Color Displays"... The paper "LED and its fabrication method" proposes a full-color MicroLED and its fabrication method, including a driving substrate. The driving substrate has several light-emitting units arranged in a rectangular array. Each light-emitting unit includes a bonding metal layer, the bottom of which is connected to the driving substrate. An epitaxial layer with a trapezoidal cross-section is located above the bonding metal layer. A passivation layer is deposited on the outer wall of the epitaxial layer, and a light-emitting port is formed in the middle of the passivation layer at the top of the epitaxial layer. An N-electrode layer is deposited on the outer wall of the passivation layer and is electrically connected to the top of the epitaxial layer. A color conversion layer with a microlens structure is wrapped above the light-emitting units. A light-blocking structure is provided between the light-emitting units. The light-blocking structure is located on the side closest to the light-emitting unit. The wall is arc-shaped; quantum dots are filled and covered to cover the entire light-emitting unit, reducing light loss from the side walls. The light surface is made into a microlens, and an arc-shaped light-blocking structure is added to prevent light crosstalk and improve the display effect. The patent "A quantum dot color conversion layer and its preparation method and application" proposes a method for preparing a quantum dot color conversion layer. By fabricating a microfluidic chip, grooves and hydrophobic substances are introduced into the microchannels of the microfluidic chip, which solves the problems of uncontrollable thickness and shape of quantum dot layer and color mixing that are easy to occur in the preparation of color conversion layer. However, the above-mentioned patents do not solve the problem of light crosstalk in the color conversion process very well, which greatly affects the product quality.

[0005] To address the aforementioned issues, a novel light-conversion full-color Micro LED chip and its fabrication method were developed and designed. Summary of the Invention

[0006] The purpose of this invention is to provide a full-color Micro LED chip with light conversion and a manufacturing method therefor, to solve the problem of light crosstalk in color conversion, and to realize full-color display with color conversion.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0008] A light-converting full-color Micro LED chip, comprising:

[0009] Transparent support substrate;

[0010] A transparent adhesive layer is provided on the transparent support substrate;

[0011] A transparent insulating protective layer is provided on the transparent adhesive layer;

[0012] The transparent insulating protective layer contains a light conversion layer and an annular light blocking layer, and the light conversion layer is completely surrounded by the annular light blocking layer.

[0013] An epitaxial structure is provided above the transparent insulating protective layer, the light conversion layer, and the annular light blocking layer;

[0014] A transparent conductive layer is provided on the epitaxial structure;

[0015] An ohmic contact electrode is provided on the epitaxial structure and the transparent conductive layer;

[0016] An insulating reflective layer is provided on the ohmic contact electrode, the transparent conductive layer, the annular light blocking layer, and the epitaxial structure, and the insulating reflective layer has a through hole extending from its top to the surface of the ohmic contact electrode.

[0017] Wiring lines are provided on the insulating reflective layer, and the wiring lines are interconnected through the through holes of the insulating reflective layer and the ohmic contact electrodes to achieve electrical connection;

[0018] An insulating layer is provided above the wiring line and the insulating reflective layer, and the insulating layer has a through hole extending from its top to the surface of the wiring line;

[0019] A wire bonding electrode is provided on the insulating layer, and the wire bonding electrode is interconnected with the wiring lines through the through-holes of the insulating layer to achieve electrical connection.

[0020] In one preferred embodiment, an annular metal circuit is disposed inside the insulating reflective layer; the annular metal circuit is located above the annular light blocking layer and completely surrounds the epitaxial structure.

[0021] In a preferred embodiment, there is a gap between the edges of the epitaxial structure and the annular metal circuit, with the gap size controlled between 0.5-10 μm.

[0022] In a preferred embodiment, the annular metal circuit and the annular light blocking layer overlap, and the overlap size is controlled within 0.5-10 μm.

[0023] In a preferred embodiment, an insulating barrier layer is inserted between the sidewall of the epitaxial structure and the annular metal line, and the insulating barrier layer completely surrounds and covers the sidewall of the epitaxial structure.

[0024] In one preferred embodiment, the transparent support substrate is made of organic or inorganic material and has a thickness of 100-500 μm.

[0025] In a preferred embodiment, the size of the light conversion layer is larger than the size of the annular light blocking layer, and the two overlap each other, with the overlap size controlled between 0.5-10 μm.

[0026] In a preferred embodiment, the thickness of the light conversion layer is greater than the thickness of the annular light blocking layer, and the difference between the two is controlled within 0.2-5 μm.

[0027] In a preferred embodiment, the epitaxial structure is surrounded by an annular light-blocking layer, and the annular light-blocking layer covers the edge of the epitaxial structure. The two overlap at the edge of the epitaxial structure, and the overlap size is controlled within 0.5-10 μm.

[0028] In addition, this application also proposes a method for fabricating a light-conversion full-color Micro LED chip, including the following steps:

[0029] S1. Prepare a blue light epitaxial unit, which includes a growth substrate and an epitaxial structure, wherein the epitaxial structure includes a negative polarity layer, a quantum well light-emitting layer and a positive polarity layer.

[0030] S2, through photolithography, etching, and resist removal, part of the positive polarity layer and quantum well light-emitting layer are etched away to expose the negative polarity layer. This step is defined as the target etching depth one.

[0031] S3, through photolithography, etching, and resist removal, continue etching the upper epitaxial structure to the target etching depth two, where the target etching depth two is less than the overall epitaxial depth;

[0032] S4, a transparent conductive layer is fabricated on the positive polarity layer through deposition, photolithography, etching, resist removal, and alloying.

[0033] S5, through photolithography, evaporation, and resist removal, ohmic contact electrodes are fabricated on the transparent conductive layer and the negative polarity layer;

[0034] S6. An insulating reflective layer is fabricated on the ohmic contact electrode, negative polarity layer, positive polarity layer and transparent conductive layer by deposition, photolithography, etching and resist removal. The insulating reflective layer has windows to expose the ohmic contact electrode.

[0035] S7, Fabricate wiring lines on the insulating reflective layer, and make electrical connections through the windows of the insulating reflective layer and ohmic contact electrodes.

[0036] S8, through deposition, photolithography, etching, and resist removal, an insulating layer is fabricated on top of the wiring and insulating reflective layer. The insulating layer has windows to expose the wiring.

[0037] S9, wire bonding electrodes are fabricated on the insulating layer, and the wire bonding electrodes achieve electrical connection through the insulating layer window and wiring lines;

[0038] S10 uses thermosetting bonding to temporarily bond the wafer to a temporary support substrate;

[0039] S11 removes the growth substrate and exposes the epitaxial structure through laser dissociation;

[0040] S12, through physical etching, part of the epitaxial structure is etched away to expose the insulating reflective layer;

[0041] S13, an annular light-blocking layer is fabricated on the epitaxial structure and insulating reflective layer by photolithography;

[0042] S14, a light conversion layer is fabricated on the epitaxial structure and the annular light blocking layer by printing.

[0043] S15, an insulating and transparent protective layer is formed on the light conversion layer, epitaxial structure and annular light blocking layer by spin coating;

[0044] S16, a transparent support substrate is fabricated on the insulating transparent protective layer by spin coating, thermosetting and bonding;

[0045] S17, the temporary support substrate is removed by laser dissociation to expose the bonding wire electrodes;

[0046] S18, cut to form a single light-converting full-color Micro LED chip.

[0047] Due to the application of the above technical solution, the beneficial effects of this application compared with the prior art are as follows:

[0048] This application provides a light-conversion full-color Micro LED chip and its manufacturing method. By redesigning the Micro LED chip and its corresponding structural layout, and providing corresponding manufacturing processes and methods, it effectively solves the problem of light crosstalk in color conversion in the prior art. Through the design of the packaging, the quality of the light excitation layer is effectively improved, preventing the occurrence of light crosstalk, greatly improving the reliability of the product, increasing production efficiency, meeting the production needs of enterprises, and enhancing their competitiveness. Attached Figure Description

[0049] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0050] Figure 1 This is a schematic diagram of the structure of a light-converting full-color Micro LED chip according to Embodiment 1 of the present invention;

[0051] Figure 2 This is a schematic diagram of the structure of a light-converting full-color Micro LED chip according to Embodiment 2 of the present invention;

[0052] Figure 3 This is a schematic diagram of the structure of a light-converting full-color Micro LED chip according to Embodiment 3 of the present invention.

[0053] Figure 4 This is a flowchart illustrating a method for fabricating a light-conversion full-color Micro LED chip according to the present invention;

[0054] Figure 5 This is a schematic diagram of the chip structure in step S1 of the manufacturing method of Embodiment 4 of the present invention;

[0055] Figure 6 This is a schematic diagram of the chip structure in step S2 of the manufacturing method of Embodiment 4 of the present invention;

[0056] Figure 7 This is a schematic diagram of the chip structure in step S3 of the manufacturing method of Embodiment 4 of the present invention;

[0057] Figure 8 This is a schematic diagram of the chip structure in step S4 of the manufacturing method of Embodiment 4 of the present invention;

[0058] Figure 9 This is a schematic diagram of the chip structure in step S5 of the manufacturing method of Embodiment 4 of the present invention;

[0059] Figure 10 This is a schematic diagram of the chip structure in step S6 of the manufacturing method of Embodiment 4 of the present invention;

[0060] Figure 11 This is a schematic diagram of the chip structure in step S7 of the manufacturing method of Embodiment 4 of the present invention;

[0061] Figure 12 This is a schematic diagram of the chip structure in step S8 of the manufacturing method of Embodiment 4 of the present invention;

[0062] Figure 13 This is a schematic diagram of the chip structure in step S9 of the manufacturing method of Embodiment 4 of the present invention;

[0063] Figure 14 This is a schematic diagram of the chip structure in step S10 of the manufacturing method of Embodiment 4 of the present invention;

[0064] Figure 15 This is a schematic diagram of the chip structure in step S11 of the manufacturing method of Embodiment 4 of the present invention;

[0065] Figure 16 This is a schematic diagram of the chip structure in step S12 of the manufacturing method of Embodiment 4 of the present invention;

[0066] Figure 17 This is a schematic diagram of the chip structure in step S13 of the manufacturing method of Embodiment 4 of the present invention;

[0067] Figure 18 This is a schematic diagram of the chip structure in step S14 of the manufacturing method of Embodiment 4 of the present invention;

[0068] Figure 19 This is a schematic diagram of the chip structure in step S15 of the manufacturing method of Embodiment 4 of the present invention;

[0069] Figure 20 This is a schematic diagram of the chip structure in step S16 of the manufacturing method of Embodiment 4 of the present invention;

[0070] Figure 21 This is a schematic diagram of the chip structure in step S17 of the manufacturing method of Embodiment 4 of the present invention;

[0071] Figure 22 This is a schematic diagram of the chip structure in step S18 of the manufacturing method of Embodiment 4 of the present invention;

[0072] Among them, 1. Growth substrate; 2. Epitaxial structure; 3. Transparent conductive layer; 4. Ohmic contact electrode; 5. Ring metal circuit; 6. Insulating reflective layer; 7. Wiring circuit; 8. Insulating layer; 9. Bonding electrode; 10. Temporary support substrate; 11. Wafer; 12. Ring light blocking layer; 13. Light conversion layer; 14. Transparent insulating protective layer; 15. Transparent adhesion layer; 16. Transparent support substrate; 17. Insulating barrier layer. Detailed Implementation

[0073] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0074] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0075] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing the invention and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0076] Furthermore, in addition to indicating direction or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in certain situations to indicate a dependency or connection. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0077] Furthermore, the terms "installation," "setup," "equipped with," "connection," "linking," and "socketing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0078] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0079] Example 1

[0080] Please see Figure 1 This application provides a light-conversion full-color Micro LED chip, comprising:

[0081] A light-converting full-color Micro LED chip, comprising:

[0082] Transparent support substrate 16; the transparent support substrate 16 is made of organic or inorganic materials, such as sapphire, quartz glass, etc., and organic materials such as PI, PET, PEEK, BCB, PPA, etc., with a thickness of 100-500um, preferably 120-300um, and more preferably 150-200um.

[0083] A transparent adhesive layer 15 is provided on the transparent support substrate 16; the transparent adhesive layer 15 is an organic material, such as PI, epoxy resin, organosilicon, etc., with a thickness of 1-10um, preferably 2-8um, and more preferably 3-5um.

[0084] A transparent insulating protective layer 14 is provided on the transparent adhesive layer 15; the transparent insulating protective layer 14 is an organic material, such as PI, epoxy resin, organosilicon, etc., with a thickness of 5-30um, preferably 8-25um, and more preferably 10-20um.

[0085] The transparent insulating protective layer 14 contains a light conversion layer 13 and an annular light blocking layer 12, and the light conversion layer 13 is completely surrounded by the annular light blocking layer 12.

[0086] The light conversion layer 13 converts the received light into different colors. For example, the epitaxial structure 2 emits blue light. The light conversion layer 13 here may include a green light conversion layer 13 and a red light conversion layer 13. The red light conversion layer 13 converts the received blue light into red light, and the green light conversion layer 13 converts the received blue light into green light.

[0087] When the light conversion layer 13 is a red light conversion layer 13, its material can be a phosphor or a quantum dot. The material can be a nitride phosphor / quantum dot composed of MAlSiNx:Re (1≤x≤5) or a phosphor / quantum dot composed of MD:Re. M is at least one selected from palladium Ba, strontium Sr, and calcium Ca. D is at least one selected from sulfur S, selenium Se, and tellurium Te. Re is at least one selected from europium Eu, yttrium Y, lanthanum La, cerium Ce, neodymium Nd, promethium Pm, and samarium Sm.

[0088] When the light conversion film is a green light conversion film, its material can be a phosphor or a quantum dot. The material can be a silicate phosphor / quantum dot composed of M2SiO4:Re or a phosphor / quantum dot composed of MA2D4:Re. M is at least one selected from palladium (Ba), strontium (Sr), and calcium (Ca). A is at least one selected from calcium (Ca), aluminum (Al), and indium (In). D is at least one selected from sulfur (S), selenium (Se), and tellurium (Te). Re is at least one selected from europium (Eu), yttrium (Y), lanthanum (La), cerium (Ce), neodymium (Nd), promethium (Pm), and samarium (Sm).

[0089] To achieve full color, two methods are used here: one is to use a blue light chip + a green light chip + a blue light chip to excite the red light conversion layer 13, and the other is to use a blue light chip + a blue light chip to excite the green light conversion layer + a blue light chip to excite the red light conversion layer.

[0090] The annular light blocking layer 12 blocks or prevents light leakage of different colors emitted through the epitaxial structure 2 or the light conversion layer 13, and prevents crosstalk between different colors of light. It can be a black light-absorbing material or a reflective material. If it is a light-absorbing material, it is mainly an organic material doped with carbon black, Fe3O4, etc. If it is a reflective material, it is mainly a DBR film material with a combination of high refractive index and low refractive index.

[0091] To prevent crosstalk and light leakage, the light conversion layer 13 is required to be completely surrounded by the annular light blocking layer 12. The size of the light conversion layer 13 is slightly larger than the size of the annular light blocking layer 12, and the two overlap each other. The overlap size is 0.5-10um, preferably 1-8um, and more preferably 2-4um.

[0092] To prevent light crosstalk and light leakage, in the overlapping area, the thickness of the light conversion layer 13 is slightly greater than the thickness of the annular light blocking layer 12, and the difference between the two is controlled within 0.2-5 μm, preferably within 1-4 μm, and more preferably within 2-3 μm.

[0093] An epitaxial structure 2 is provided on the transparent insulating protective layer 14, the light conversion layer 13, and the annular light blocking layer 12; the epitaxial structure 2 includes a negative polarity layer, a quantum well light-emitting layer, and a positive polarity layer;

[0094] To prevent crosstalk and light leakage, the epitaxial structure 2 is required to be completely surrounded by the annular light blocking layer 12. The annular light blocking layer 12 covers the edge of the epitaxial structure 2, and the two overlap at the edge of the blue light epitaxial structure 2. The overlap size is controlled at 0.5-10 μm, preferably at 1-8 μm, and more preferably at 2-4 μm.

[0095] To prevent crosstalk and light leakage, a sandwich structure is formed between the edge of the epitaxial structure 2, the edge of the light conversion layer 13, and the annular light blocking layer 12, that is, the annular light blocking layer 12 is sandwiched between the epitaxial structure 2 and the light conversion layer.

[0096] A transparent conductive layer 3 is provided on the epitaxial structure 2; the transparent conductive layer 3 is ITO and has a thickness of 30-200nm.

[0097] An ohmic contact electrode 4 is provided on the epitaxial structure 2 and the transparent conductive layer 3. The ohmic contact is a metal stacked material, with the bottom layer being an ohmic contact adhesion layer, which can be a metal material such as Ni or Cr, the middle layer being a buffer layer, which can be a metal material such as Al or Au, and the top layer being an etched contact layer, which can be a metal material such as Ti, Pt, Ni, or Cr. Part of it contacts the negative polarity layer of the epitaxial structure 2, and the other part contacts the transparent conductive layer 3, thereby realizing the electrical connection between the two.

[0098] An insulating reflective layer 6 is provided on the ohmic contact electrode 4, the transparent conductive layer 3, the annular light blocking layer 12, and the epitaxial structure 2, and the insulating reflective layer 6 has a through hole extending from its top to the surface of the ohmic contact electrode 4; the insulating reflective layer 6 is a DBR film material with a combination of high and low refractive indices, with a thickness of 1-7 μm, preferably 2-5 μm, and more preferably 3-4 μm, the low refractive material being SiO, MgF, etc., and the high refractive material being HfO2, Ta2O5, etc.;

[0099] To prevent crosstalk and light leakage, the insulating reflective layer 6 between different sections of the epitaxial structure 2 must be completely covered by the annular light blocking layer 12, that is, the size of the annular light blocking layer 12 is larger than the gap between different sections of the blue light epitaxial structure 2.

[0100] The through-hole of the insulating reflective layer 6 is required to extend from its top to the surface of the ohmic contact electrode 4. Its shape can be circular, elliptical, square, rhomboid, etc.; its bottom surface size is required to be smaller than the size of its corresponding ohmic contact electrode 4, and the width between the two sides is 1-8um, preferably 2-6um, more preferably 3-5um, and its aperture size is required to gradually increase from the bottom surface to the top surface.

[0101] A wiring line 7 is provided on the insulating reflective layer 6, and the wiring line 7 is interconnected with the ohmic contact electrode 4 through the through hole of the insulating reflective layer 6 to achieve electrical connection; the wiring line 7 is a layered metal material, and its bottom and top layers are both metal bonding materials such as Ti, Ni, Cr, etc., and it is interconnected with the ohmic contact electrode 4 through the through hole of the insulating reflective layer 6.

[0102] An insulating layer 8 is provided above the wiring line 7 and the insulating reflective layer 6, and the insulating layer 8 has a through hole extending from its top to the surface of the wiring line 7; the insulating layer 8 is required to have good insulation performance, and it can be an organic insulating material or an inorganic insulating material, such as PI, PET, BCB, SiO2, etc.; the through hole of the insulating layer 8 is required to extend from the top surface of the insulating layer 8 to the surface of the wiring line 7, and its shape can be circular, elliptical, square, rhomboid, etc.; its bottom surface dimension is required to be smaller than the corresponding wiring line 7 dimension, and the width between the two sides is 1-8 μm, preferably 2-6 μm, more preferably 3-5 μm, and its aperture size is required to gradually increase from the bottom surface to the top surface;

[0103] A wire bonding electrode 9 is provided on the insulating layer 8, and the wire bonding electrode 9 is interconnected through the through holes of the insulating layer 8 and the wiring line 7 to achieve electrical connection; the wire bonding electrode 9 is a layered metal material, the bottom layer is a metal bonding material such as Ti, Ni, Cr, etc., and the top layer is a welding material of Au, Sn or their alloys, which is interconnected through the through holes of the insulating layer 8 and the wiring line 7.

[0104] Example 2

[0105] Please see Figure 2 To further reduce optical crosstalk and light leakage, a ring-shaped metal line 5 is provided inside the insulating reflective layer 6. The ring-shaped metal line 5 further blocks or prevents light leakage of different colors emitted through the epitaxial structure 2 or the light conversion layer 13. It is a metal stacked material, with the bottom layer being an adhesion layer, which can be a metal material such as Ni or Cr; the middle layer being a buffer layer, which can be a metal material such as Al or Au; and the top layer being an etched contact layer, which can be a metal material such as Ti, Pt, Ni, or Cr.

[0106] To prevent crosstalk and light leakage, the epitaxial structure 2 is required to be completely surrounded by the annular metal line 5, with a gap between the two at the edge. The gap size is controlled between 0.5-10 μm, preferably between 1-8 μm, and more preferably between 2-4 μm.

[0107] Example 3

[0108] Please see Figure 3 To further reduce optical crosstalk and light leakage, an insulating barrier layer 17 is inserted between the sidewall of the epitaxial structure 2 and the annular metal line 5. The insulating barrier layer 17 completely surrounds and covers the sidewall of the epitaxial structure 2, preventing the annular metal line 5 from contacting the sidewall, the top transparent conductive layer 3, and the positive polarity layer of the epitaxial structure 2. Its material is an inorganic insulating material, such as SiO2, Si3N4, MgF, etc.

[0109] Example 4

[0110] Please refer to Figure 4-13. This application also proposes a method for fabricating a light-conversion full-color Micro LED chip, comprising the following steps:

[0111] S1. Prepare a blue light epitaxial unit, which includes a growth substrate 1 and an epitaxial structure 2, wherein the epitaxial structure 2 includes a negative polarity layer, a quantum well light-emitting layer, and a positive polarity layer, as shown below. Figure 5 As shown;

[0112] S2, through photolithography, etching, and resist stripping, partially etches away the positive polarity layer and the quantum well light-emitting layer, exposing the negative polarity layer. This step is defined as the target etching depth one. Figure 6 As shown;

[0113] S3, through photolithography, etching, and resist removal, continue etching the upper epitaxial structure 2 to the target etching depth two. The target etching depth two is less than the overall epitaxial depth, such as... Figure 7 As shown;

[0114] S4, a transparent conductive layer 3 is fabricated on the positive polarity layer through deposition, photolithography, etching, resist removal, and alloying. Figure 8 As shown;

[0115] S5, ohmic contact electrodes 4 are fabricated on the transparent conductive layer 3 and the negative polarity layer through photolithography, evaporation, and resist removal. Figure 9 As shown;

[0116] S6, an insulating reflective layer 6 is fabricated on the ohmic contact electrode 4, negative polarity layer, positive polarity layer, and transparent conductive layer 3 through deposition, photolithography, etching, and resist removal. The insulating reflective layer 6 has windows that expose the ohmic contact electrode 4. Figure 10 As shown;

[0117] S7, Wiring lines 7 are fabricated on the insulating reflective layer 6. The wiring lines 7 are electrically connected through the window of the insulating reflective layer 6 and the ohmic contact electrode 4, such as... Figure 11 As shown;

[0118] S8, through deposition, photolithography, etching, and resist removal, an insulating layer 8 is fabricated on top of the wiring lines 7 and the insulating reflective layer 6. The insulating layer 8 has windows to expose the wiring lines 7, such as... Figure 12 As shown;

[0119] S9, a wire bonding electrode 9 is fabricated on the insulating layer 8. The wire bonding electrode 9 is electrically connected through the window of the insulating layer 8 and the wiring line 7, such as Figure 13 As shown;

[0120] S10, the wafer 11 is temporarily bonded to the temporary support substrate 10 by thermosetting bonding, such as... Figure 14 As shown;

[0121] S11, the growth substrate 1 is removed by laser dissociation, exposing the epitaxial structure 2, such as... Figure 15 As shown;

[0122] S12, by physical etching, part of the epitaxial structure 2 is etched away, exposing the insulating reflective layer 6, such as... Figure 16 As shown;

[0123] S13, using photolithography, a ring-shaped light-blocking layer 12 is fabricated on the epitaxial structure 2 and the insulating reflective layer 6, such as... Figure 17 As shown;

[0124] S14, a light conversion layer 13 is fabricated on the epitaxial structure 2 and the annular light blocking layer 12 by printing, such as Figure 18 As shown;

[0125] S15, an insulating and transparent protective layer is fabricated on the light conversion layer 13, the epitaxial structure 2, and the annular light blocking layer 12 by spin coating, such as... Figure 19 As shown;

[0126] S16, a transparent support substrate 16 is fabricated on the insulating transparent protective layer through spin coating, thermosetting, and bonding, such as... Figure 20 As shown;

[0127] S17, the temporary support substrate 10 is removed by laser dissociation, exposing the bonding wire electrode 9, as shown. Figure 21 As shown;

[0128] S18, cut to form a single light-converting full-color Micro LED chip, such as Figure 22 As shown.

[0129] This application provides a light-conversion full-color Micro LED chip and its manufacturing method. By redesigning the Micro LED chip and its corresponding structural layout, and providing corresponding manufacturing processes and methods, it effectively solves the problem of light crosstalk in color conversion in the prior art. Through the design of the packaging, the quality of the excitation light of the color conversion layer 13 is effectively improved, preventing the occurrence of light crosstalk, greatly improving the reliability of the product, increasing production efficiency, meeting the production needs of enterprises, and enhancing the competitiveness of enterprises.

[0130] Finally, it should be noted that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A light-converting full-color Micro LED chip, characterized in that, include: Transparent support substrate; A transparent adhesive layer is provided on the transparent support substrate; A transparent insulating protective layer is provided on the transparent adhesive layer; The transparent insulating protective layer contains a light conversion layer and an annular light blocking layer, and the light conversion layer is completely surrounded by the annular light blocking layer. An epitaxial structure is provided above the transparent insulating protective layer, the light conversion layer, and the annular light blocking layer; A transparent conductive layer is provided on the epitaxial structure; An ohmic contact electrode is provided on the epitaxial structure and the transparent conductive layer; An insulating reflective layer is provided on the ohmic contact electrode, the transparent conductive layer, the annular light blocking layer, and the epitaxial structure, and the insulating reflective layer has a through hole extending from its top to the surface of the ohmic contact electrode. Wiring lines are provided on the insulating reflective layer, and the wiring lines are interconnected through the through holes of the insulating reflective layer and the ohmic contact electrodes to achieve electrical connection; An insulating layer is provided above the wiring line and the insulating reflective layer, and the insulating layer has a through hole extending from its top to the surface of the wiring line; A wire bonding electrode is provided on the insulating layer, and the wire bonding electrode is interconnected with the wiring lines through the through holes of the insulating layer to achieve electrical connection.

2. The light-converting full-color Micro LED chip as described in claim 1, characterized in that, The insulating reflective layer contains an annular metal circuit; the annular metal circuit is located above the annular light blocking layer and completely surrounds the outer extension structure.

3. The light-conversion full-color Micro LED chip as described in claim 2, characterized in that, There is a gap at the edge of the epitaxial structure and the annular metal circuit, and the gap size is controlled between 0.5-10um.

4. The light-converting full-color Micro LED chip as described in claim 2, characterized in that, The annular metal circuit and the annular light blocking layer overlap, and the overlap size is controlled between 0.5-10 μm.

5. The light-converting full-color Micro LED chip as described in claim 2, characterized in that, An insulating barrier layer is inserted between the sidewall of the epitaxial structure and the annular metal line, and the insulating barrier layer completely surrounds and covers the sidewall of the epitaxial structure.

6. The light-converting full-color Micro LED chip as described in claim 1, characterized in that, The transparent support substrate is made of organic or inorganic materials and has a thickness of 100-500 μm.

7. The light-converting full-color Micro LED chip as described in claim 1, characterized in that, The size of the light conversion layer is larger than that of the annular light blocking layer, and the two overlap each other, with the overlap size controlled between 0.5-10 μm.

8. The light-converting full-color Micro LED chip as described in claim 7, characterized in that, The thickness of the light conversion layer is greater than the thickness of the annular light blocking layer, and the difference between the two is controlled within 0.2-5 μm.

9. The light-converting full-color Micro LED chip as described in claim 1, characterized in that, The epitaxial structure is surrounded by an annular light blocking layer, and the annular light blocking layer covers the edge of the epitaxial structure. The two overlap at the edge of the epitaxial structure, and the overlap size is controlled between 0.5-10 μm.

10. A method for fabricating a light-converting full-color Micro LED chip, characterized in that, Includes the following steps: S1. Prepare a blue light epitaxial unit, which includes a growth substrate and an epitaxial structure, wherein the epitaxial structure includes a negative polarity layer, a quantum well light-emitting layer and a positive polarity layer. S2, through photolithography, etching, and resist removal, part of the positive polarity layer and quantum well light-emitting layer are etched away to expose the negative polarity layer. This step is defined as the target etching depth one. S3, through photolithography, etching, and resist removal, continue etching the upper epitaxial structure to the target etching depth two, where the target etching depth two is less than the overall epitaxial depth; S4, a transparent conductive layer is fabricated on the positive polarity layer through deposition, photolithography, etching, resist removal, and alloying. S5, through photolithography, evaporation, and stripping to remove resist, ohmic contact electrodes are fabricated on the transparent conductive layer and the negative polarity layer; S6. An insulating reflective layer is fabricated on the ohmic contact electrode, negative polarity layer, positive polarity layer and transparent conductive layer by deposition, photolithography, etching and resist removal. The insulating reflective layer has windows to expose the ohmic contact electrode. S7, Fabricate wiring lines on the insulating reflective layer, and make electrical connections through the windows of the insulating reflective layer and ohmic contact electrodes. S8, through deposition, photolithography, etching, and resist removal, an insulating layer is fabricated on top of the wiring and insulating reflective layer. The insulating layer has windows to expose the wiring. S9, wire bonding electrodes are fabricated on the insulating layer, and the wire bonding electrodes achieve electrical connection through the insulating layer window and wiring lines; S10 uses thermosetting bonding to temporarily bond the wafer to a temporary support substrate; S11 removes the growth substrate and exposes the epitaxial structure through laser dissociation; S12, through physical etching, part of the epitaxial structure is etched away to expose the insulating reflective layer; S13, an annular light-blocking layer is fabricated on the epitaxial structure and insulating reflective layer by photolithography; S14, a light conversion layer is fabricated on the epitaxial structure and the annular light blocking layer by printing. S15, an insulating and transparent protective layer is formed on the light conversion layer, epitaxial structure and annular light blocking layer by spin coating; S16, a transparent support substrate is fabricated on the insulating transparent protective layer by spin coating, thermosetting and bonding; S17, the temporary support substrate is removed by laser dissociation to expose the bonding wire electrodes; S18, cut to form a single light-converting full-color Micro LED chip.

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