Micro-LED display chip and method for manufacturing the same

Abstract

The present invention provides a Micro-LED display chip and a manufacturing method thereof. The method includes providing a driving substrate including a driving circuit and a contact electrically connected to the driving circuit, providing a first LED layer including a plurality of first LED units, a first filling structure located between the first LED units, and a first columnar conductor penetrating the first filling structure, bonding the first LED layer and the driving substrate, electrically connecting the first LED units and the first columnar conductor to the contact respectively, disposing a second LED layer on the first LED layer, the second LED layer including a plurality of second LED units and a second filling structure located between the second LED units, electrically connecting the second LED units to the first columnar conductor directly below them, and the emission colors of the second LED units and the first LED units being different. It is advantageous for reducing the difficulty of the manufacturing process of a full-color Micro-LED display chip.

Description

Technical Field

[0001] <Cross-reference to Related Applications> This application claims priority to a PCT application with application number PCT / CN2023 / 098893 filed with the Chinese Patent Office on June 15, 2022 (this PCT application claims priority to a Chinese patent application with application number 202210675860.X, invention title "Micro-LED Display Chip and Its Manufacturing Method" filed with the Chinese Patent Office on June 15, 2022), and all of its contents are hereby incorporated by reference into this application.

[0002] This specification relates to the field of semiconductor electronic components, and specifically to Micro-LED display chips and their manufacturing methods.

Background Art

[0003] With the emergence of micro-LED (Micro-LED) display technology, high-resolution micro-devices such as augmented reality (AR), near-eye display (NED) devices, and wearable display devices are made as display devices. Micro-LEDs have great market potential due to advantages such as small size, high brightness, fast response, and long lifespan.

[0004] Currently, Micro-led full-color display chips usually incorporate a wavelength conversion layer into a monochromatic display chip, set the three primary colors RGB required for full-color display, and meet the full-color display requirements. However, the LED array of micro-LED display is densely integrated, and the LED pixel pitch within the array is in the unit of 0.1 to 100 microns. The smaller the pixel of the Micro-led display chip, the more difficult it is to fabricate the wavelength conversion layer, and the fabrication of the Micro-led display chip for color display becomes significantly more difficult.

Summary of the Invention

[0005] Based on this point, in multiple embodiments of this specification, a Micro-LED display chip and its manufacturing method for realizing multi-color or full-color display of the Micro-LED display chip are proposed, aiming to reduce the difficulty of manufacturing the multi-color or full-color Micro-LED display chip, avoid damage to the driving substrate to a certain extent in the manufacturing process, improve the yield, and reduce the manufacturing cost.

[0006] In an embodiment of this specification, a method for manufacturing a Micro-LED display chip is provided, including providing a driving substrate including a driving circuit and a contact electrically connected to the driving circuit, providing a first LED layer including a plurality of first LED units, a first filling structure located between the first LED units, and a first columnar conductor penetrating the first filling structure, bonding the first LED layer and the driving substrate so that the first LED unit and the first columnar conductor are electrically connected to the contact respectively, and arranging a second LED layer on the first LED layer, where the second LED layer includes a plurality of second LED units and a second filling structure located between the second LED units, and the second LED units are electrically connected to the first columnar conductor directly below them, and the emission colors of the second LED units and the first LED units are different.

[0007] In an embodiment of this specification, a Micro-LED display chip is provided, including a driving substrate including a driving circuit and a contact electrically connected to the driving circuit, a first LED layer including a plurality of first LED units, a first filling structure located between the first LED units, and a first columnar conductor penetrating the first filling structure, the first LED layer being arranged on the driving substrate so as to be electrically connected to the contact together with the first columnar conductor respectively, a second LED layer including a plurality of second LED units and a second filling structure located between the second LED units, the second LED layer being electrically connected to the first columnar conductor directly below it, and the emission color of the second LED layer being different from that of the first LED units.

[0008] In an embodiment of this specification, a display panel is provided, and the display panel includes any of the above Micro-LED display chips.

[0009] In an embodiment of this specification, a display device is provided, and the display device includes any of the above Micro-LED display chips.

[0010] The manufacturing method of the Micro-LED display chip according to the embodiment of this specification is to arrange a filling structure between a plurality of first LED units of a first LED layer, and arrange a first columnar conductor penetrating the first filling structure between the fillers. The first LED unit and the first columnar conductor are respectively electrically connected to a driving circuit through contacts. A plurality of second LED units and a second filling structure located between the second LED units are arranged on the first LED layer. The second LED unit is electrically connected to the first columnar conductor directly below it. By making the emission colors of the second LED unit and the first LED unit different, multi-color display is realized. Since the LED display chip can realize multi-color display even without a wavelength conversion layer, the difficulty of manufacturing the LED chip is reduced to a certain extent.

[0011] Furthermore, after forming the first LED layer and the second LED layer respectively, by sequentially connecting the first LED layer and the second LED layer to the driving substrate, the driving substrate can drive and control the first LED unit and the second LED unit individually, reduce the number of times the driving substrate is inserted into the process, protect the driving substrate, and avoid damage to the driving substrate to a certain extent in the manufacturing process. Therefore, the yield of the Micro-LED display chip is improved to a certain extent and the cost is reduced.

Brief Description of the Drawings

[0012]

Figure 1

Figures 2a - 2m

Figures 3a - 3h

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0013] Hereinafter, while referring to the drawings of some embodiments of this specification, the technical solutions of some embodiments of this specification will be clearly and fully described. However, it is clear that the described embodiments are some embodiments of this specification and not all embodiments. Based on the embodiments in this specification, all embodiments obtained by those skilled in the art without creative labor are included within the scope of this specification.

[0014] Embodiments of this specification provide a method for manufacturing a Micro-LED display chip. The method for manufacturing the Micro-LED display chip includes the following steps.

[0015] S110: Provide a driving substrate 300, and the driving substrate 300 includes a driving circuit and contacts electrically connected to the driving circuit.

[0016] Refer to FIG. 1. In some embodiments, the driving substrate 300 includes a semiconductor material. The semiconductor material may be at least one of silicon, silicon carbide, gallium nitride, germanium, gallium arsenide, indium phosphide, etc. The driving substrate 300 may be composed of a non-conductive material such as glass, plastic, or sapphire wafer. The driving substrate 300 may be a CMOS substrate or a TFT substrate. The driving substrate 300 includes a driving circuit, and the driving circuit (not shown in FIG. 1) provides an electrical signal to the LED unit and controls the brightness of the LED unit using the electrical signal. It can be understood that the LED unit means one or more of the first LED unit 210, the second LED unit 410, and the third LED unit 510.

[0017] Refer to FIG. 1. In some embodiments, the driving substrate 300 includes contacts 310. There may be a plurality of contacts 310, and the contacts 310 may be spaced apart from each other. The material of the contacts 310 includes at least one of Cu, Ag, Au, Al, W, Mo, Ni, Ti, Pt, Pd, etc. Each of the contacts 310 is connected to the driving circuit and the LED unit, so that through the electrical connection between the driving circuit and the LED unit, the driving of the driving circuit for the LED unit is realized, and the LED unit is caused to emit light. The contacts 310 may be located on the surface of the substrate, which is advantageous for the electrical connection between the driving circuit and the LED unit.

[0018] S120: Provide the first LED layer 200. The first LED layer 200 includes a plurality of first LED units 210, a first filling structure 220 located between the first LED units 210, and a first columnar conductor 221 penetrating the first filling structure 220.

[0019] Refer to FIG. 2a. In some embodiments, the first LED unit 210 is formed by processing a first LED epitaxial layer 200a including a first doped semiconductor layer 211, an active layer 212, and a second doped semiconductor layer 213. In the first LED epitaxial layer 200a, a part of the thickness of a part of the first doped semiconductor layer 211, the active layer 212, and the second doped semiconductor layer 213 can be removed to form the first LED unit 210.

[0020] In some embodiments, the materials of the first doped semiconductor layer 211 and the second doped semiconductor layer 213 may be II-VI or III-V nitrides. Specifically, for example, the first doped semiconductor layer 211 and the second doped semiconductor layer 213 may each be a single-layer or multi-layer semiconductor structure composed of one or more of ZnSe, ZnO, GaN, AlN, InN, InGaN, GaP, AlInGaP, or AlGaAs. The active layer 212 may be any of a single quantum well structure, a multiple quantum well (MQW) structure, or a structure in which quantum wells and barrier layers are stacked. The active layer 212 is located between the first doped semiconductor layer 211 and the second doped semiconductor layer 213. Holes and electrons are excited in the active layer 212 to generate light of a specific wavelength.

[0021] In some embodiments, the first doped semiconductor layer 211 may be a P-type semiconductor layer, and the second doped semiconductor layer 213 may be an N-type semiconductor layer. The first doped semiconductor layer 211 and the second doped semiconductor layer 213 may each be electrically connected to the contact 310 and the common electrode 600, and the common electrode 600 may be a cathode. The contact 310 may be electrically connected to the first doped semiconductor layer 211 via an anode. In some embodiments, the first doped semiconductor layer 211 may be an N-type semiconductor layer, while the second doped semiconductor layer 213 is a P-type semiconductor layer.

[0022] Refer to FIG. 2a. In some embodiments, the first LED epitaxial layer 200a includes a first doped semiconductor layer 211, an active layer 212, and a second doped semiconductor layer 213. The first LED epitaxial layer 200a may be grown and formed on a substrate 100. The substrate 100 may be any of sapphire, Si, GaAs, InP, GaN, AlN, SiC substrates, etc.

[0023] In some embodiments, the first LED layer 200 includes a plurality of first LED units 210, and the first LED units 210 can be independently driven. The first LED unit 210 includes a first doped semiconductor layer 211, an active layer 212, and a second doped semiconductor layer 213. The first doped semiconductor layer 211 may be used for electrical connection to a contact 310, and the second doped semiconductor layer 213 may be used for electrical connection to a common electrode 600.

[0024] In some embodiments, a conductive layer may be formed on the first doped semiconductor layer 211 of the first LED unit 210. The conductive layer may be a metal material or indium tin oxide. The first LED unit 210 and the contact are electrically connected through the conductive layer of the first doped semiconductor layer 211.

[0025] Refer to FIGS. 2a and 2b. In some embodiments, in the step of providing the first LED layer, providing the first LED epitaxial layer 200a, etching the first LED epitaxial layer 200a to form a plurality of first LED units 210, each of the first LED 210 units including a first doped semiconductor layer 211, an active layer 212, and a second doped semiconductor layer 213, and the second doped semiconductor layers 213 of adjacent first LED units 210 being connected to each other. The first LED epitaxial layer 200a includes the first doped semiconductor layer 211, the active layer 212, and the second doped semiconductor layer 213. It can be understood that a partial region of the first doped semiconductor layer 211, the active layer 212, and a partial thickness of the second doped semiconductor layer 213 are removed to form a plurality of first LED units 210. A partial region of the first doped semiconductor layer 211 and the active layer 212 are completely removed, while the second doped semiconductor layer 213 is partially retained. In contrast, a plurality of first LED units 210 are formed, and the first LED units 210 are connected to each other via the second doped semiconductor layer 213. FIG. 2b shows two first LED units 210 connected by the second doped semiconductor layer 213. A partial region of the first LED epitaxial layer 200a may be removed in the etching process. Specifically, the etching process may be dry etching or wet etching.

[0026] In some embodiments, in the step of providing the first LED layer 200, providing a first LED epitaxial layer 200a, etching the first LED epitaxial layer 200a to form a plurality of first LED units 210 spaced apart from each other, and each of the first LED units 210 includes a first doped semiconductor layer 211, an active layer 212, and a second doped semiconductor layer 213. Specifically, a first LED epitaxial layer 200a may be provided, but the first LED epitaxial layer 200a includes a first doped semiconductor layer 211, an active layer 212, and a second doped semiconductor layer 213, and a partial region of the first LED epitaxial layer 200a is removed to form a plurality of first LED units 210 spaced apart from each other. With respect to a partial region of the first LED epitaxial layer 200a being removed, a plurality of first LED units 210 are formed in the non-removed first LED epitaxial layer 200a, and a spatial gap is provided between the plurality of first LED units 210 to form a plurality of first LED units 210 spaced apart from each other.

[0027] In some embodiments, the first LED units 210 are independent of each other. Since the first LED units 210 are formed by removing a part or all of the thickness in a partial region of the first LED epitaxial layer 200a, no first LED epitaxial layer 200a is retained between the plurality of first LED units 210, or only a part of the thickness of the epitaxial layer 200a of the first LED unit 210 is retained. Therefore, an uneven surface is formed between the plurality of first LED units 210.

[0028] Refer to FIG. 2c. In some embodiments, the step of providing the first LED layer includes disposing the first filling structure 220 between the first LED units 210. The first LED layer 200 includes a first filling structure 220 that forms a first flat surface from a plurality of first LED units 210. By disposing the first filling structure 220, the unevenness characteristics of the surface formed by the plurality of first LED units 210 are reduced. By disposing the first filling structure 220, the thickness of the first LED layer 200 in each region is substantially the same, so that a first flat surface is formed.

[0029] In some embodiments, the first filling structure 220 is disposed between the first LED units 210, and the first filling structure 220 is at least located in the circumferential direction of the first LED units 210. Refer to FIG. 2c. The first filling structure 220 may be located in the circumferential direction of the first LED units 210. Refer to FIG. 3a. Alternatively, the first filling structure 220 covers the first LED units 210. Specifically, the first filling structure 220 may be formed by at least one of processes such as deposition and coating. The material of the first filling structure 220 may be selected from polyimide, wall protection tape, OC adhesive, SU8 photoresist, or benzocyclobutene (BCB). Refer to FIG. 2d. In some embodiments, a first columnar conductor 221 penetrating the first filling structure 220 is disposed in the first filling structure 220. A first opening penetrating the first filling structure 220 is formed, a conductive material is disposed in the first opening, and the first columnar conductor 221 is formed. The material of the first columnar conductor 221 may be a transparent conductive material. Specifically, for example, the transparent conductive material may be indium tin oxide. Of course, the material of the first columnar conductor 221 further includes a metal material. The first columnar conductor 221 is used for the electrical connection between the first LED unit 210 and the contact 310. Also, the first columnar conductor 221 is used for the electrical connection between the first LED unit 210 and an LED unit having a different emission color and the contact 310. For example, the electrical connection between the second LED unit and the contact 310.

[0030] The first LED layer 200 includes a first filling structure 220. The first filling structure 220 is advantageous for the planarization of the first LED layer 200 and reduces the difficulty of bonding between the first LED layer and the driving substrate 300. Further, the first filling structure 220 plays a role in protecting and stabilizing the first LED unit. For the first LED units 210 spaced apart from each other, the first filling structure 220 also improves the difficulty of bonding between the first LED unit 210 and the driving substrate 300 and the stability after bonding between the first LED unit 210 and the driving substrate 300, reduces the peeling risk of the first LED unit 210 in the manufacturing process, and improves the yield of the Micro-LED display chip.

[0031] S130: Bond the first LED layer 200 and the driving substrate 300, and the first LED unit 210 and the first columnar conductor 221 are each electrically connected to the contact point 310.

[0032] Referring to FIG. 2e. In some embodiments, the first LED unit 210 and the first columnar conductor 221 are each electrically connected to the contact point 310. The first LED layer 200 includes the first columnar conductor 221 located between the first LED units 210. Further, the first LED layer 200 includes the first columnar conductor 221 in contact with the first doped semiconductor layer 211 of the first LED unit 210. The first LED unit 210 is electrically connected to the contact point 310 through the first columnar conductor 221. In some embodiments, the first filling structure 220 is only located in the circumferential direction of the first LED unit 210, and the first columnar conductor 221 may not be disposed between the first LED unit 210 and the first columnar conductor 221, but the first LED unit 210 is electrically connected to the contact point 310 through the first doped semiconductor layer 211.

[0033] After forming the first LED layer 200 including the first LED unit 210, the first filling structure 220, and the first columnar conductor 221, the process flow of bonding the driving substrate 300 is used to protect the driving substrate 300 and improve the yield. If there is a defect in the first LED layer 200, only the first LED layer 200 can be repaired or discarded without affecting the driving substrate 300, which is advantageous for cost reduction.

[0034] S140: Place the second LED layer 400 on the first LED layer 200. The second LED layer 400 includes a plurality of second LED units 410 and a second filling structure 420 located between the second LED units 410. Electrically connect the second LED unit 410 to the first columnar conductor 221 directly below it, and the emission colors of the second LED unit 410 and the first LED unit 210 are different.

[0035] Refer to FIGS. 2c, 2b and 2f. In some embodiments, the first LED epitaxial layer 200a is etched to form a plurality of first LED units 210, each of the first LED units 210 includes a first doped semiconductor layer 211, an active layer 212 and a second doped semiconductor layer 213, and when the second doped semiconductor layers 213 of adjacent first LED units 210 are connected to each other, before the step of disposing the second LED layer 400 on the first LED layer, further, the second doped semiconductor layer 213 of the first LED unit 210 is thinned until the tip of the first columnar conductor 221 is exposed, and the plurality of first LED units 210 after thinning are spaced apart from each other. To thin the second doped semiconductor layer 213 of the first LED unit 210, it may be thinned by etching, or each region of the second doped semiconductor layer 213 is thinned simultaneously. Due to the surface contact between the first filling structure 220 and the second doped semiconductor layer 213, the first columnar conductor 221 penetrates the first filling structure 220. Therefore, when the tip of the first columnar conductor 221 is exposed, the second doped semiconductor layer 213 that realizes the connection of the plurality of first LED units 210 is blocked, and on the first columnar conductor 221, the surface opposite to the first doped semiconductor layer 211 is exposed, and the plurality of first LED units 210 are spaced apart from each other, and the first filling structure 220 is between the first LED units 210.

[0036] Retain a part of the thickness of the second doped semiconductor layer 213, and after bonding the first LED layer 200 and the driving substrate 300, thin the second doped semiconductor layer 213 to improve the stability of the first LED unit 210 and prevent the first LED unit 210 from falling off during the bonding process. Also, after thinning, the plurality of first LED units 210 are spaced apart from each other, which contributes to the electrical connection and independent driving of the second LED unit 410 and the contact point 310.

[0037] In some embodiments, the first LED layer 200 is disposed on the surface of the substrate 100, or the first LED epitaxial layer 200a is grown on the substrate 100 to be formed. Before thinning the second doped semiconductor layer 213 of the first LED unit 210, it includes removing the substrate 100. In order to retain a part of the thickness of the second doped semiconductor layer 213, a part of the risk that the first LED unit 210 is simultaneously removed in the substrate 100 removal process is reduced, and the manufacturing yield is improved to a certain extent.

[0038] In some embodiments, after forming a plurality of first LED units 210 spaced apart from each other, a conductive layer is formed on the second doped semiconductor layer 213 of the first LED unit 210. The conductive material of the conductive layer is a metal material or indium tin oxide. The first LED unit 210 is electrically connected to the second columnar conductor 421 through the conductive layer of the second doped semiconductor layer 213. FIG. 2f does not show the conductive layer of the second doped semiconductor layer 213. In some embodiments, a conductive layer is disposed on the surfaces of the first doped semiconductor layer and the second doped semiconductor layer of the LED unit, and the conductive layer is used for the electrical connection between the LED unit and the corresponding contact or the corresponding columnar conductor. The LED unit may be the first LED unit, or the second LED unit, or the third LED unit.

[0039] Referring to FIGS. 2g and 2h. In some embodiments, in the step of disposing the second LED layer 400 on the first LED layer 200, providing the second LED layer 400, the second LED layer 400 includes a plurality of second LED units 410 and a second filling structure 420 located between the second LED units 410, joining the second LED layer 400 and the first LED layer 200, and electrically connecting the second LED unit 410 to the first columnar conductor 221 directly below it, so as to realize the electrical connection with the contact 310.

[0040] In some embodiments, the second LED epitaxial layer 400a includes a first doped semiconductor layer, an active layer, and a second doped semiconductor layer. Referring to FIG. 2a, it can be understood that the first doped semiconductor layer, the active layer, and the second doped semiconductor layer are not shown in FIG. 2g respectively. The first doped semiconductor layer and the second doped semiconductor layer included in the second LED epitaxial layer 400a may be the same as or different from the first doped semiconductor layer 211 and the second doped semiconductor layer 213 included in the first LED epitaxial layer 200a.

[0041] In some embodiments, the second LED unit 410 is formed by processing a second LED epitaxial layer 400a including a first doped semiconductor layer, an active layer, and a second doped semiconductor layer. Refer to the formation of the first LED unit 210. There may be a space between the second LED units 410 formed after processing the second LED epitaxial layer 400a, or they may be connected through the second doped semiconductor layer. FIG. 2h shows two second LED units 410.

[0042] In some embodiments, the second filling structure 420 refers to the first filling structure 220. Refer to FIG. 2i. In some embodiments, the second filling structure 420 is at least located in the circumferential direction of the second LED unit 410. Specifically, the second filling structure 420 may be located in the circumferential direction of the second LED unit 410, or the second filling structure 420 may cover the second LED unit 410.

[0043] In some embodiments, a conductive layer may be formed on the surface of the first doped semiconductor layer of the second LED unit 410. The conductive material of the conductive layer is a metal material or indium tin oxide. The second LED unit 210 and the first columnar conductor 221 are electrically connected through the conductive layer on the surface of the first doped semiconductor layer of the second LED unit 210. The conductive layer on the surface of the first doped semiconductor layer is not shown in FIGS. 2j and 2k.

[0044] Refer to FIG. 2j. In some embodiments, a second columnar conductor 421 penetrating a second filling structure 420 is disposed in the second LED layer 400, and the number and position of the second columnar conductors 421 are arranged by the first LED unit 210. The second LED layer 400 includes a second columnar conductor 421 located directly above the first LED unit 210. The second columnar conductor 421 is used for the electrical connection between the first LED unit 210 and the common electrode 600.

[0045] Refer to FIG. 2k. In some embodiments, the second LED unit 410 realizes the electrical connection with the contact point 310 through the electrical connection with the first columnar conductor 221 directly below it. In some embodiments, the second LED unit 410 and the first LED unit 210 are spaced apart from each other. The orthographic projection of the first columnar conductor 221 directly below the second LED unit 410 in the second LED unit 410 is located within the first doped semiconductor layer of the second LED unit 410. The first doped semiconductor layer of the second LED unit 410 is electrically connected to the first columnar conductor 221 directly below the second LED unit 410, thereby realizing the electrical connection between the second LED unit 410 and the contact point 310. In some embodiments, the first doped semiconductor layer of the second LED unit 410 and the first columnar conductor 221 are electrically connected to realize the electrical connection by direct contact.

[0046] In some embodiments, a second columnar conductor 421 penetrating the second filling structure 420 is disposed in the second LED layer 400. The second columnar conductors 421 located directly above the first LED unit 210 are electrically connected to the second doped semiconductor layer 213 of the first LED unit 210 respectively, which is advantageous for the electrical connection between the first LED unit 210 and the common electrode 600. The emission color of the second LED unit 410 is different from that of the first LED unit 210. Even without a wavelength conversion structure, multi-color display can be realized, the difficulty of manufacturing can be reduced, and the manufacturing efficiency can be improved.

[0047] Refer to FIG. 2l. In some embodiments, the second LED epitaxial layer 400a is disposed on the substrate 100. When the second LED layer 400 and the first LED layer 200 are bonded, it includes the removal of the substrate 100. When connected to the second doped semiconductor layer of the second LED unit 410, it includes thinning the second LED layer 400 until the tip of the second columnar conductor 421 is exposed. Specifically, since reference can be made to thinning the second doped semiconductor layer 213 of the first LED unit 210 described above until the tip of the first columnar conductor 221 is exposed, it is omitted here.

[0048] In some embodiments, to dispose the second LED layer 400 on the first LED layer 200, the second LED unit 410 and the first LED layer 200 are bonded respectively, and a second filling structure 420 is disposed between the second LED units 410. Also, a second columnar conductor 421 penetrating the second filling structure 420 may be disposed.

[0049] In the method for manufacturing a Micro-LED display chip according to the embodiments of the present specification, since the second LED unit 410 and the first LED unit 210 with different emission colors are disposed, multi-color display can be realized even without a wavelength conversion layer. Due to the characteristic that the size of the LED unit of the Micro-LED display chip is small, there are drawbacks such as high difficulty in manufacturing the wavelength conversion layer and low conversion efficiency. Therefore, by disposing the second LED unit 410 and the first LED unit 210 with different emission colors, the manufacturing difficulty is reduced and the luminous efficiency is increased. Since the process flow of forming the first LED layer 200 including the first LED unit 210, the first filling structure 220, and the first columnar conductor 221 and then bonding the first LED layer 200 and the driving substrate 300 is used, the driving substrate 300 is protected, the yield is improved, and the cost is reduced.

[0050] In some embodiments, the first LED unit 210 and the second LED unit 410 are independently driven by electrically connecting the second doped semiconductor layer of the second LED unit 410 and the second columnar conductor 421 to a common electrode 600, respectively.

[0051] Referring to FIG. 2m, in some embodiments, to electrically connect the second doped semiconductor layer 213 and the second columnar conductor 421 of the second LED unit 410 to the common electrode 600, an electrical connection is realized by direct contact. Alternatively, other conductive structures are arranged to realize the electrical connection.

[0052] In some embodiments, in the second LED layer 400, the common electrode 600 is disposed on the surface opposite to the driving substrate 300. The second doped semiconductor layer 213 and the second columnar conductor 421 of the second LED unit 410 are each electrically connected to the common electrode 600, and the second LED unit 410 and the first LED unit 210 are independently driven. The common electrode 600 is advantageous for reducing the driving difficulty.

[0053] In some embodiments, a plurality of common electrodes 600 are disposed. Here, the second doped semiconductor layer 213 and the second columnar conductor 421 of the second LED unit 410 are each electrically connected to the common electrode 600. Each second LED unit 410 and each first LED unit 210 may be provided with corresponding common electrodes 600.

[0054] Refer to FIGS. 3a, 3b, and 3c. In some embodiments, the first LED unit 210 is electrically connected to the contact 310 of the driving substrate 300 via a corresponding first columnar conductor 221. Specifically, in the first LED layer 200, in the step of disposing the first columnar conductor 221 that penetrates the first filling structure 220 while the first filling structure 220 covers the first LED unit 210, the first columnar conductor 221 is disposed on the first LED unit 210, and the first LED unit 210 is electrically connected to the contact 310 via the corresponding first columnar conductor 221.

[0055] In some embodiments, to cover the first doped semiconductor layer 211 of the first LED unit 210 with the first filling structure 220, a through hole for the first filling structure 220 to penetrate the first doped semiconductor layer 211 is disposed, the through hole is filled with a conductive material, and a first columnar conductor 221 for connecting the first LED unit 210 is formed. On the contrary, the first LED layer 200 and the driving substrate 300 are joined, and the electrical connection between the first LED unit 210 and the contact 310 is realized by the first columnar conductor 221 for connecting the first LED unit 210, and the first LED unit 210 and the contact 310 realize electrical connection by an indirect connection.

[0056] By disposing the first filling structure 220 that covers the first LED unit 210, the difficulty of manufacturing the first filling structure 220 is reduced, and by disposing the first columnar conductor 221, the bonding strength between the first LED layer 200 and the driving substrate 300 is improved, peeling between the first LED layer and the driving substrate 300 in the manufacturing process is avoided, and the yield is improved.

[0057] Refer to FIG. 3e. In some embodiments, to cover the second LED unit 410, the second filling structure 420 forms a through hole in the second filling structure 420 of the first doped semiconductor layer covering the second LED unit 410, fills the through hole with a conductive material, and forms a second columnar conductor 421 for connecting the second LED unit 410 and the first columnar conductor 221. In contrast, the second LED unit 410 is electrically connected to the contact 310 via the first columnar conductor 221 and the second columnar conductor 421. The second LED unit 410 and the first columnar conductor 221 achieve electrical connection through an indirect connection.

[0058] Refer to FIGS. 3b, 3d, 3e, and 4. A second columnar conductor 421 penetrating the second filling structure 420 is disposed in the second filling structure 420, and the second columnar conductor 421 is electrically connected to the first columnar conductor 221 directly below it.

[0059] Refer to FIG. 3f. In some embodiments, the second LED epitaxial layer 400a is disposed on the substrate 100. When the second LED layer 400 and the first LED layer 200 are joined, it includes removing the substrate 100. When connected to the second doped semiconductor layer of the second LED unit 410, it includes thinning the second LED layer 400 until the tip of the second columnar conductor 421 is exposed. Specifically, reference can be made to thinning the second doped semiconductor layer 213 of the first LED unit 210 described above until the tip of the first columnar conductor 221 is exposed, which is omitted here.

[0060] In some embodiments, a conductive layer may be formed on the surface of the second doped semiconductor layer of the second LED unit 410. The conductive material of the conductive layer is a metal material or indium tin oxide. The conductive layer of the second doped semiconductor layer of the second LED unit 210 is used for the electrical connection between the second LED unit 210 and the third columnar conductor 521.

[0061] Refer to FIGS. 3g and 5. In some embodiments, the method for manufacturing the Micro-LED display chip further includes disposing a third LED layer 500 on the second LED layer 400, where the third LED layer 500 includes a plurality of third LED units 510 and a third filling structure 520 located between the third LED units 510, realizing electrical connection between the third LED unit 510 and the contact 310 through the first columnar conductor 221 and the second columnar conductor 421 directly below it, and the emission colors of the third LED unit 510, the second LED unit 410, and the first LED unit 210 being different. By disposing the second columnar conductor 421 electrically connected to the first columnar conductor 221 and the third LED unit with different emission colors between the first LED unit and the second LED unit, the color display range of the Micro-LED display chip and the application range of the Micro-LED display chip are expanded.

[0062] In some embodiments, the third LED unit 510 is formed by processing a third epitaxial layer including a first doped semiconductor layer, an active layer, and a second doped semiconductor layer. The third LED unit 510 includes a stacked first doped semiconductor layer, an active layer, and a second doped semiconductor layer. Specifically, reference can be made to the manufacturing of the first LED unit 210, which is omitted here.

[0063] In some embodiments, a conductive layer is formed on the surface of the first doped semiconductor layer of the third LED unit 510. The conductive material of the conductive layer is a metal material or indium tin oxide. When the third columnar conductor 521 is not disposed directly below the third LED unit 510, the third LED unit 510 and the second columnar conductor 421 are electrically connected by the conductive layer in the first doped semiconductor layer of the third LED unit 510.

[0064] Refer to FIGS. 3g and 5. In some embodiments, to cover the third LED unit 510, a through hole penetrating the third filling structure 520 is arranged in the first doped semiconductor layer, and the through hole is filled with a conductive material to form a third columnar conductor 521 for electrically connecting the third LED unit 510. In contrast, the third LED unit 510 is electrically connected to the contact 310 via the first columnar conductor 221, the second columnar conductor 421, and the third columnar conductor 521 directly below it. The third LED unit 510 and the second columnar conductor 421 achieve electrical connection through an indirect connection.

[0065] In some embodiments, a conductive layer is formed on the surface of the first doped semiconductor layer of the third LED unit 510. The conductive material of the conductive layer is a metal material or indium tin oxide. The third LED unit 510 and the third columnar conductor 521 are electrically connected via the conductive layer in the first doped semiconductor layer of the third LED unit 510.

[0066] In some embodiments, the emission color of the third LED unit 510, the emission color of the second LED unit 410, and the emission color of the first LED unit 210 are different, and the emission color of the third LED unit 510, the emission color of the second LED unit 410, and the emission color of the first LED unit 210 may be red, blue, and green, respectively. By arranging a plurality of LED units with different emission colors, the display color range of the Micro-LED display chip is expanded, and the application range of the Micro-LED display chip is expanded.

[0067] Refer to FIG. 3h. In some embodiments, the third filling structure 520 further includes a third columnar conductor 521 penetrating through the third filling structure 520. The method for manufacturing the Micro-LED display chip further includes disposing a common electrode 600 on the third LED layer. Here, the first LED unit 210 is electrically connected to the common electrode 600 through the second columnar conductor 421 and the third columnar conductor 521 directly above it. The second LED unit 410 is electrically connected to the common electrode 600 through the third columnar conductor 521 directly above it. The third LED unit 510 is electrically connected to the common electrode 600. The third LED unit 510 is electrically connected to the common electrode 600 through the second doped semiconductor layer. The third LED unit 510, the second LED unit 410, and the first LED unit 210 are each independently driven. The material of the common electrode 600 may use a transparent conductive material. The common electrode 600 is formed in the evaporation process. By disposing the common electrode 600 on the surface of the third LED layer 500 opposite to the driving substrate 300, the flatness, electrical connection stability, and yield of the common electrode 600 are improved.

[0068] Embodiments of this specification provide a Micro-LED display chip. The Micro-LED display chip includes a driving substrate 300 including a driving circuit and a contact 310 electrically connected to the driving circuit, a first LED layer 200 disposed on the driving substrate 300, and a second LED layer 400 disposed on the first LED layer 200. Here, the first LED layer 200 includes a plurality of first LED units 210, a first filling structure 220 located between the first LED units 210, and a first columnar conductor 221 penetrating the first filling structure 220. The first LED units 210 and the first columnar conductor 221 are each electrically connected to the contact 310. The second LED layer 400 includes a plurality of second LED units 410 and a second filling structure 420 located between the second LED units 410. The second LED units 410 are electrically connected to the first columnar conductor 221 directly below them, and the light-emitting colors of the second LED units 410 and the first LED units 210 are different.

[0069] Refer to FIG. 6. In some embodiments, the first LED layer 200 includes a plurality of first LED units 210 spaced apart from each other. The first LED unit 210 includes a first doped semiconductor layer 211, an active layer 212, and a second doped semiconductor layer 213. For the plurality of first LED units 210, the first doped semiconductor layers 211, the active layers 212, and the second doped semiconductor layers 213 are all spaced apart from each other. The first doped semiconductor layer 211, the active layer 212, and the second doped semiconductor layer 213 are stacked, and since the active layer 212 is located between the first doped semiconductor layer 211 and the second doped semiconductor layer 213, the second doped semiconductor layer 213 is located on the side opposite to the driving substrate 300 in the first doped semiconductor layer 211. In some embodiments, for the first columnar conductor 221 directly below the second LED unit 410, the orthographic projection of the first columnar conductor 221 onto the second LED unit 410 is located within the first doped semiconductor layer of the second LED unit 410. The first columnar conductor 221 directly below the second LED unit 410 is connected to the first doped semiconductor layer of the second LED unit 410, and the second LED unit 410 is electrically connected to the contact point 310 via the first columnar conductor 221.

[0070] In some embodiments, the first LED unit 210 is electrically connected to the contact point 310 of the driving substrate 300. Refer to FIG. 6. There may be no first columnar conductor 221 disposed between the first LED unit 210 and the driving substrate 300.

[0071] Refer to FIGS. 6 and 2c. In some embodiments, the first LED layer 200 includes a first filling structure 220 located between the first LED units 210. The first filling structure 220 is used to form a first flat surface on the first LED layer 200. There is a gap between the first LED units 210, and a height difference is formed between the first LED units 210. The first filling structure 220 is located in the circumferential direction centered on the first LED units 210 at least among a plurality of the first LED units 210, reduces or eliminates the height difference located between the first LED units 210, improves the flatness of the entire Micro-LED display chip, and improves the stability of the Micro-LED display chip structure.

[0072] Refer to FIG. 6. In some embodiments, the first filling structure 220 is located in the circumferential direction of the first LED units 210. The first filling structure 220 is located in the circumferential direction of the first LED units 210. For example, the first filling structure 220 is located on the side surface centered on the first LED units 210 among the first LED units 210.

[0073] Refer to FIG. 7. In some embodiments, the first LED units 210 are embedded in the first filling structure 220. In contrast, the first filling structure 220 is located in the circumferential direction of the first LED units 210 and covers the surface of the first doped semiconductor layer 211 of the first LED units 210 approaching the substrate 300. The first LED units 210 are embedded in the structure of the first filling structure 220. The difficulty of manufacturing the first filling structure 220 is reduced, and the manufacturing efficiency is improved.

[0074] Refer to FIG. 7. In some embodiments, when the first LED units 210 are embedded in the first filling structure 220, a first columnar conductor 221 penetrating the first filling structure 220 is disposed directly below the first LED units 210, and the first columnar conductor 221 is electrically connected to the first doped semiconductor layer 211 of the first LED units 210 and the contact 310.

[0075] In some embodiments, the first columnar conductor 221 directly below the first LED unit 210 is in contact with the surface of the first doped semiconductor layer 211 of the first LED unit 210 on the side opposite to the second doped semiconductor layer 213 of the first LED unit 210.

[0076] Referring to FIG. 6 or FIG. 7. In some embodiments, a first columnar conductor 221 penetrating the first filling structure 220 is disposed in the first filling structure 220, and is spaced apart from the first columnar conductor 221 and the first LED unit 210, and is used for electrical connection with the second LED unit 410.

[0077] In some embodiments, the second LED layer 400 is disposed on the surface of the first LED layer 200 opposite to the driving substrate 300. In the second LED layer, at least the second filling structure 420 is in contact with the first LED layer 200, or the second filling structure 420 and the first doped semiconductor layer 211 of the first LED unit 210 are in contact with the first LED layer 200.

[0078] Referring to FIG. 6. In some embodiments, the second filling structure 420 is located in the circumferential direction of the second LED unit 410. The second filling structure 420 is located in the circumferential direction of the second LED unit 410. For example, the second filling structure 420 is located on the side surface centered on the second LED unit 410 between the second LED units 410.

[0079] Referring to FIG. 7. In some embodiments, the second LED unit 410 is embedded in the second filling structure 420. Specifically, the second filling structure 420 is located in the circumferential direction of the second LED unit 410 and covers the surface of the second LED unit 410 approaching the first LED unit 210. The difficulty of manufacturing the second filling structure 420 is reduced, and the manufacturing efficiency is improved.

[0080] Refer to FIG. 7. In some embodiments, when the second LED unit 410 is embedded in the second filling structure 420, directly below the second filling structure 420, there is further disposed a second columnar conductor 421 penetrating the second filling structure 420, and the second columnar conductor 421 is electrically connected to the first doped semiconductor layer of the second LED unit 410 and the first columnar conductor 221.

[0081] In some embodiments, the second columnar conductor 421 directly below the second filling structure 420 is in contact with the surface of the first doped semiconductor layer of the second LED unit 410 approaching the first LED unit 210.

[0082] In some embodiments, the second filling structure 420 is provided with a second columnar conductor 421 penetrating the second filling structure 420, and the second columnar conductor 421 and the second LED unit 410 are spaced apart and used for electrical connection with the first LED unit 210.

[0083] In some embodiments, the emission color of the second LED unit 410 is different from that of the first LED unit 210. The first LED unit 210 and the first columnar conductor 221 are each electrically connected to the contact 310, and the second LED unit 410 is electrically connected to the first columnar conductor 221 directly below it. The first LED unit 210 and the second LED unit 410 are each independently driven to realize multi-color display of the Micro-LED display chip and expand the application range of the Micro-LED display chip. Regarding a plurality of second LED units 410, since a plurality of first LED units 210 with spaces therebetween can be referred to, they are omitted here.

[0084] The Micro-LED display chip according to the embodiments of the present specification has a first LED unit 210 and a second LED unit 410 with different emission colors arranged in a first LED layer 200 and a second LED layer 400 respectively. When there is no wavelength conversion layer, multi-color display can be realized. And due to the characteristics that the size of the LED unit of the Micro-LED display chip is small, the manufacturing difficulty of the wavelength conversion layer is high, and the conversion efficiency is low, by arranging the second LED unit 410 and the first LED unit 210 with different emission colors, the manufacturing difficulty can be reduced, the luminous efficiency and the yield can be improved. Also, by arranging the first filling structure 220 and the second filling structure 420, the first LED unit 210 and the second LED unit 410 can be protected, and the flatness between the film layers and the stability of the Micro-LED display chip structure can be improved.

[0085] Refer to FIG. 8. In some embodiments, a second columnar conductor 421 penetrating the second filling structure 420 is arranged in the second filling structure 420. The Micro-LED display chip further includes a third LED layer 500 arranged in the second LED layer 400. Here, the third LED layer 500 includes a plurality of third LED units 510 and a third filling structure 520 located between the third LED units 510. The third LED unit 510 realizes electrical connection with the contact 310 through the first columnar conductor 221 and the second columnar conductor 421 directly below it. The emission colors of the third LED unit 510, the second LED unit 410, and the first LED unit 210 are all different.

[0086] Refer to FIG. 8. In some embodiments, the materials of the first columnar conductor 221, the second columnar conductor 421, and the third columnar conductor 521 may be the same. The material may be a transparent conductive material or a metal, etc.

[0087] In some embodiments, the third LED layer 500 includes a plurality of third LED units 510 spaced apart from each other. The third LED unit 510 includes a first doped semiconductor layer, an active layer, and a second doped semiconductor layer, and the first doped semiconductor layers, active layers, and second doped semiconductor layers of the plurality of third LED units 510 are spaced apart from each other. The first doped semiconductor layer, the active layer, and the second doped semiconductor layer are stacked, and the active layer is located between the first doped semiconductor layer and the second doped semiconductor layer. It can be understood that the second doped semiconductor layer of the third LED unit 510 is located on the side opposite to the driving substrate 300 in the first doped semiconductor layer of the third LED unit 510. The first doped semiconductor layer of the third LED unit 510 is electrically connected to the second columnar conductor 421 and the first columnar conductor 221 directly below it, realizing the electrical connection between the third LED unit 510 and the contact point 310.

[0088] In some embodiments, the third LED layer 500 further includes a third filling structure 520. The third filling structure 520 is used to form a plurality of third LED units 510 on the third flat surface in the third LED layer 500. The third filling structure 520 is located in the circumferential direction of the third LED unit 510. The third filling structure 520 is located in the circumferential direction of the third LED unit 510. For example, the third filling structure 520 is located on the side surface centered on the third LED unit 510 between the third LED units 510.

[0089] In some embodiments, the third LED unit 510 is embedded in the third filling structure 520. Specifically, the third filling structure 520 is located in the circumferential direction of the first LED unit 210 and covers the surface of the first doped semiconductor layer of the third LED unit 510 that approaches the second LED unit 410, reducing the manufacturing difficulty of the third filling structure 520 and improving the manufacturing efficiency.

[0090] Refer to FIG. 8. In some embodiments, when the third LED unit 510 is embedded in the third filling structure 520, a third columnar conductor 521 penetrating the third filling structure 520 is disposed directly below the third LED unit 510, and the first doped semiconductor of the third columnar conductor 521 and the third LED unit 510 are electrically connected. The third LED unit 510 is electrically connected to the contact 310 via the third columnar conductor 521, the second columnar conductor 421, and the first columnar conductor 221 directly below it.

[0091] In some embodiments, the third columnar conductor 521 directly below the third LED unit 510 is in contact with the surface of the first doped semiconductor layer approaching the second LED unit 410.

[0092] In some embodiments, a third columnar conductor 521 penetrating the third filling structure 520 is further disposed in the third filling structure 520. A third columnar conductor 521 located between the third LED units 510 is disposed in the third filling structure 520 and is used for the electrical connection between the second LED unit 410 or the first LED unit 210 and the common electrode. A third columnar conductor 521 located directly below the third LED unit 510 is disposed in the third filling structure 520 and is used for the electrical connection between the third LED unit 510 and the contact 310.

[0093] In some embodiments, the Micro-LED display chip further includes a common electrode 600 disposed in the third LED layer 500. Here, the first LED unit 210 is electrically connected to the common electrode 600 via the second columnar conductor 421 and the third columnar conductor 521 directly above it, the second LED unit 410 is electrically connected to the common electrode 600 via the third columnar conductor 521 directly above it, and the third LED unit 510 is electrically connected to the common electrode 600.

[0094] In some embodiments, the emission colors of the first LED unit 210, the second LED unit 410, and the third LED unit 510 are each selected from any one of red, green, and blue. The emission colors of the first LED unit 210, the second LED unit 410, and the third LED unit 510 are different from each other, which is advantageous for realizing full-color display. In some embodiments, the emission colors of the first LED unit 210, the second LED unit 410, and the third LED unit 510 are selected from any colors such as purple and yellow, expanding the application range of the Micro-LED display chip.

[0095] In some embodiments, the Micro-LED display chip is divided into a plurality of pixel units arranged in an array. The pixel unit includes at least one of the first LED units 210, at least one of the second LED units 410, and at least one of the third LED units 510. Here, the numbers of the first LED units 210, the second LED units 410, and the third LED units 510 included in the pixel unit are not exactly the same. Refer to FIG. 9. One pixel unit shown in the dashed frame of FIG. 9 includes two first LED units 210, one second LED unit 410, and one third LED unit 510.

[0096] In some embodiments, the emission colors of the first LED unit 210, the second LED unit 410, and the third LED unit 510 are red, green, and blue respectively. In one pixel unit, the number of the second LED units 410 is greater than the number of the first LED units 210, the number of the second LED units 410 is greater than the number of the third LED units 510. By forming one pixel from the numbers of the first LED unit, the second LED unit, and the third LED unit, a plurality of single-pixel forming methods are provided.

[0097] In an embodiment of this specification, a display panel is provided, and the display panel includes any of the above Micro-LED display chips.

[0098] In this embodiment, the display panel includes any of the above Micro-LED display chips. Since the range of display colors of the Micro-LED display chip becomes larger, the range of display colors of the display panel and the application range of the display panel become larger.

[0099] In an embodiment of this specification, a display device is provided, and the display device includes any of the above Micro-LED display chips.

[0100] In this embodiment, the display device includes any of the above Micro-LED display chips. Since the range of display colors of the Micro-LED display chip becomes larger and the range of display colors of the display device becomes larger, the application range of the display device becomes larger.

[0101] The multiple embodiments in this specification themselves focus on highlighting the different parts from another embodiment, and the embodiments are interpreted in light of each other. Any combination made by those skilled in the art based on general technical knowledge for the multiple embodiments in this specification is also included in the disclosure scope of this specification.

[0102] Each technical feature of the above embodiments can be combined arbitrarily. For the sake of convenience of description, all possible combinations of each technical feature in the above embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should all be regarded as within the scope described in this specification.

[0103] The above description is only a part of the embodiments in this specification and does not limit this specification. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this specification should be included within the disclosure scope of this specification.

Claims

1. A method for manufacturing a Micro-LED display chip, comprising: providing a driving substrate including a driving circuit and a contact electrically connected to the driving circuit; providing a first LED layer including a plurality of first LED units, a first filling structure located between the first LED units, and a first columnar conductor penetrating the first filling structure; bonding the first LED layer and the driving substrate so that the first LED unit and the first columnar conductor are electrically connected to the contact respectively; placing a plurality of second LED layers, each of which includes a second LED unit and a second filling structure located between the second LED units, electrically connecting the second LED unit to the first columnar conductor directly below it, and arranging the second LED layer on the first LED layer so that the emission colors of the second LED unit and the first LED unit are different. A method for manufacturing a Micro-LED display chip is characterized by the above.

2. In the step of providing the first LED layer, providing a first LED epitaxial layer; etching the first LED epitaxial layer to form a plurality of first LED units, each of the first LED units including a first doped semiconductor layer, an active layer, and a second doped semiconductor layer, and the second doped semiconductor layers of adjacent first LED units being connected to each other; arranging the first filling structure between the first LED units; arranging the first columnar conductor penetrating the first filling structure. The method for manufacturing a Micro-LED display chip according to claim 1 is characterized by the above.

3. Before the step of arranging the second LED layer on the first LED layer, further comprising: thinning the second doped semiconductor layer of the first LED unit until the tip of the first columnar conductor is exposed, wherein the plurality of first LED units after thinning are spaced apart from each other. The method for manufacturing a Micro-LED display chip according to claim 2 is characterized by the above.

4. In the step of providing the first LED layer, providing a first LED epitaxial layer; Etch the first LED epitaxial layer to form a plurality of first LED units spaced apart from each other, each of the first LED units including a first doped semiconductor layer, an active layer, and a second doped semiconductor layer, arrange the first filling structure between the first LED units, and arrange the first columnar conductor penetrating the first filling structure. The manufacturing method of the Micro-LED display chip according to claim 1 is characterized by including the above.

5. In the first LED layer, the first filling structure covers the first LED units, whereas, in the step of arranging the first columnar conductor penetrating the first filling structure, arrange a first columnar conductor in the first LED unit, and electrically connect the first LED unit to the contact via the corresponding first columnar conductor. The manufacturing method of the Micro-LED display chip according to claim 1 is characterized by including the above.

6. In the step of arranging a second LED layer on the first LED layer, provide a second LED layer including a plurality of second LED units and a second filling structure located between the second LED units, and bond the second LED layer and the first LED layer such that the second LED units achieve electrical connection to the contact by electrical connection to the first columnar conductor directly below them. The manufacturing method of the Micro-LED display chip according to claim 1 is characterized by including the above.

7. A second columnar conductor penetrating the second filling structure is further arranged in the second filling structure, and the second columnar conductor is electrically connected to the first columnar conductor directly below it. The manufacturing method of the Micro-LED display chip further includes arranging a third LED layer on the second LED layer, where the third LED layer includes a plurality of third LED units and a third filling structure located between the third LED units, and the third LED units are electrically connected to the contact via the first columnar conductor and the second columnar conductor directly below them. The manufacturing method of the Micro-LED display chip according to claim 1 is characterized in that the emission colors of the third LED units, the second LED units, and the first LED units are different from each other.

8. The third filling structure further includes a third columnar conductor penetrating the third filling structure, and the method for manufacturing the Micro-LED display chip further includes disposing a common electrode on the third LED layer, where the first LED unit is electrically connected to the common electrode through the second columnar conductor and the third columnar conductor directly above it, the second LED unit is electrically connected to the common electrode through the third columnar conductor directly above it, and the third LED unit is electrically connected to the common electrode. The method for manufacturing a Micro-LED display chip according to claim 7, characterized in that

9. A Micro-LED display chip, comprising a driving substrate including a driving circuit and a contact electrically connected to the driving circuit, a plurality of first LED units, a first filling structure located between the first LED units, and a first columnar conductor penetrating the first filling structure, and a first LED layer disposed on the driving substrate so as to be electrically connected to the contact together with the first columnar conductor, a plurality of second LED units and a second filling structure located between the second LED units, the second LED unit being electrically connected to the first columnar conductor directly below it, and a second LED layer disposed on the first LED layer such that the emission colors of the second LED unit and the first LED unit are different. A Micro-LED display chip, characterized in that

10. The second filling structure further includes a second columnar conductor penetrating the second filling structure, the Micro-LED display chip further includes a third LED layer disposed on the second LED layer, where the third LED layer includes a plurality of third LED units and a third filling structure located between the third LED units, the third LED unit realizes electrical connection with the contact through the first columnar conductor and the second columnar conductor directly below it, and the emission colors of the third LED unit, the second LED unit, and the first LED unit are different from each other. The Micro-LED display chip according to claim 9, characterized in that

11. In the third filling structure, a third columnar conductor penetrating the third filling structure is further arranged, and the Micro-LED display chip further includes a common electrode arranged in the third LED layer. Here, the first LED unit is electrically connected to the common electrode through the second columnar conductor and the third columnar conductor directly above it, the second LED unit is electrically connected to the common electrode through the third columnar conductor directly above it, and the third LED unit is electrically connected to the common electrode. The Micro-LED display chip according to claim 10, characterized in that.

12. The Micro-LED display chip is divided into a plurality of pixel units arranged in an array, and the pixel unit includes at least one of the first LED units, at least one of the second LED units, and at least one of the third LED units. Here, the number of the first LED units, the number of the second LED units, and the number of the third LED units included in the pixel unit are not exactly the same. The Micro-LED display chip according to claim 10, characterized in that.

13. The emission color of the first LED unit, the emission color of the second LED unit, and the emission color of the third LED unit are each selected from any of red, green, and blue. The Micro-LED display chip according to claim 10, characterized in that.

14. The first LED unit is embedded in the first filling structure, and the first LED unit is electrically connected to the contact through the first columnar conductor directly below it, and / or the second LED unit is embedded in the second filling structure, and the second LED unit realizes electrical connection with the contact through the second columnar conductor and the first columnar conductor directly below it. The Micro-LED display chip according to claim 10, characterized in that.

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