Micro-led display device and manufacturing method therefor

Abstract

Disclosed in the present application are a micro-LED display device and a manufacturing method therefor. The device comprises a display substrate and a driving substrate bonded to each other. The display substrate comprises a light-emitting epitaxial layer and pixel electrodes, wherein the light-emitting epitaxial layer comprises a first semiconductor layer, an active layer and a second semiconductor layer, and the pixel electrodes are arranged on one side of the first semiconductor layer and are electrically connected to the first semiconductor layer. The driving substrate comprises a substrate body and power supply electrodes, wherein the power supply electrodes are arranged on one side of the substrate body. The light-emitting epitaxial layer is provided with first via holes, which run through the light-emitting epitaxial layer. The micro-LED display device comprises first metal pillars filling the first via holes, wherein the first metal pillars are electrically insulated from the light-emitting epitaxial layer, and the first metal pillars are connected to the power supply electrodes, and each form a conductive path between a power supply electrode and a pixel electrode. By means of the method, the present application can reduce the difficulty of bonding a driving substrate and a display substrate, and simplify the manufacturing process of micro-LED display devices, thereby improving the yield of micro-LED display devices.

Description

Micro-LED display device and preparation method thereof

[0001] The present application claims priority to Chinese Patent Application No. 2024107112849, filed on June 3, 2024, entitled "Micro-LED display device and preparation method thereof", the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD

[0002] The present application relates to the technical field of semiconductor light-emitting diodes, in particular to a Micro-LED display device and a preparation method thereof.

BACKGROUND

[0003] LED (Light Emitting Diode) is a kind of semiconductor component that can convert electrical energy into visible light, and is a lighting source widely used in modern indication, display, decoration, backlight, general lighting and urban night scene fields.

[0004] At present, the Micro-LED display device usually adopts a bonding method to connect the substrate provided with display pixel points for emitting light and the substrate for power supply. However, after bonding, the electrical connection between the display pixel points and the substrate for power supply in the Micro-LED display device needs to be ensured, so the current bonding method is to respectively set electrodes on the bonding interfaces of the two substrates to respectively connect with the pixel points and the power supply electrodes, so that after the two substrates are bonded, the display pixel points and the substrate for power supply can realize power supply through the bonding electrodes of the bonding interface. However, such a bonding method is difficult, which leads to a low yield of the Micro-LED display device.

SUMMARY

[0005] Embodiments of the present application provide a Micro-LED display device and a preparation method thereof, which can reduce the bonding difficulty of the driving substrate and the display substrate, thereby simplifying the preparation process of the Micro-LED display device and improving the yield of the Micro-LED display device.

[0006] In a first aspect, the embodiments of the present application provide a Micro-LED display device, which comprises a display substrate and a driving substrate bonded to each other in a laminated manner, the display substrate comprises a light-emitting epitaxial layer and a pixel electrode, the light-emitting epitaxial layer comprises a first semiconductor layer, an active layer and a second semiconductor layer arranged in a laminated manner in sequence along a laminating direction of the display substrate and the driving substrate, the pixel electrode is arranged on a side of the first semiconductor layer away from the active layer and is in conductive connection with the first semiconductor layer, the driving substrate comprises a substrate body and a plurality of power supply electrodes, the plurality of power supply electrodes are arranged on a side of the substrate body facing the first semiconductor layer, the light-emitting epitaxial layer is provided with a first via hole penetrating through the light-emitting epitaxial layer, and the Micro-LED display device further comprises a first metal column filled in the first via hole, the first metal column is in electrical insulation with the light-emitting epitaxial layer along a hole wall of the first via hole, the first metal column is further in fixed connection with the power supply electrode and forms a conductive path between the power supply electrode and the pixel electrode.

[0007] In a second aspect, the embodiments of the present application provide a preparation method of a Micro-LED display device, which comprises the following steps:

[0008] providing a display substrate and a driving substrate bonded to each other in a laminated manner, wherein the display substrate comprises a light-emitting epitaxial layer and a pixel electrode, the light-emitting epitaxial layer comprises a first semiconductor layer, an active layer and a second semiconductor layer arranged in a laminated manner in sequence along a laminating direction of the display substrate and the driving substrate, the pixel electrode is arranged on a side of the first semiconductor layer away from the active layer and is in conductive connection with the first semiconductor layer, the driving substrate comprises a substrate body and a plurality of power supply electrodes, the plurality of power supply electrodes are arranged on a side of the substrate body facing the first semiconductor layer;

[0009] forming a first via hole penetrating through the light-emitting epitaxial layer from a side of the light-emitting epitaxial layer away from the driving substrate;

[0010] filling a first metal column in the first via hole, wherein the first metal column is in electrical insulation with the light-emitting epitaxial layer along a hole wall of the first via hole, the first metal column is further in fixed connection with the power supply electrode and forms a conductive path between the power supply electrode and the pixel electrode.

[0011] The beneficial effects of the present application are: different from the prior art, the present application forms a first via hole in the light-emitting epitaxial layer and sets a first metal column in the first via hole, the first metal column penetrates the light-emitting epitaxial layer and contacts the pixel electrode and the power supply electrode in the driving substrate, so that a conductive path is formed between the power supply electrode and the pixel electrode, and the setting of the first metal column can make the display substrate and the driving substrate not need to set electrode bonding between the bonding interface to electrically connect the pixel electrode and the power supply electrode, thereby reducing the bonding difficulty of the driving substrate and the display substrate, thereby simplifying the preparation process of the Micro-LED display device and improving the yield of the Micro-LED display device. BRIEF DESCRIPTION OF DRAWINGS

[0012] FIG. 1 is a structural schematic diagram of an embodiment of the Micro-LED display device of the present application;

[0013] FIG. 2 is a structural schematic diagram of another embodiment of the Micro-LED display device of the present application;

[0014] FIG. 3 is a structural schematic diagram of a second via hole of the Micro-LED display device of the present application;

[0015] FIG. 4 is a flow step schematic diagram of an embodiment of the preparation method of the Micro-LED display device of the present application;

[0016] FIG. 5 is a corresponding preparation process schematic diagram of the manufacturing method of the Micro-LED display device of the embodiment shown in FIG. 4;

[0017] FIG. 6 is a corresponding another preparation process schematic diagram of the manufacturing method of the Micro-LED display device shown in FIG. 4;

[0018] FIG. 7 is a corresponding still another preparation process schematic diagram of the manufacturing method of the Micro-LED display device shown in FIG. 4;

[0019] FIG. 8 is a corresponding still another preparation process schematic diagram of the manufacturing method of the Micro-LED display device shown in FIG. 4;

[0020] FIG. 9 is a corresponding still another preparation process schematic diagram of the manufacturing method of the Micro-LED display device shown in FIG. 4;

[0021] FIG. 10 is a flow step schematic diagram of another embodiment of the preparation method of the Micro-LED display device of the present application;

[0022] FIG. 11 is a corresponding preparation process schematic diagram of the manufacturing method of the Micro-LED display device of the embodiment shown in FIG. 10

[0023] FIG. 12 is another corresponding preparation process schematic diagram of the Micro-LED display device manufacturing method shown in FIG. 10;

[0024] FIG. 13 is still another corresponding preparation process schematic diagram of the Micro-LED display device manufacturing method shown in FIG. 10;

[0025] FIG. 14 is yet another corresponding preparation process schematic diagram of the Micro-LED display device manufacturing method shown in FIG. 10.

DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0027] The present inventor has found that the current Micro-LED display device usually uses a bonding method to connect the substrate provided with display pixel points for emitting light and the substrate for power supply. However, after bonding, the electrical connection between the display pixel points and the substrate for power supply needs to be ensured. Therefore, the current method is to respectively provide electrodes on the bonding interfaces of the two substrates to respectively connect with the pixel points and the power supply electrodes, so that after the two substrates are bonded, the display pixel points and the substrate for power supply can realize power supply through the bonding electrodes of the bonding interface. However, such a bonding method is difficult to implement, resulting in a low yield of the Micro-LED display device. In order to solve the above problems, the following embodiments are proposed.

[0028] The following is an exemplary description of the structure of the Micro-LED display device according to the embodiments of the present application.

[0029] The Micro-LED display device 10 refers to a device capable of forming a plurality of display pixel points 101 inside to generate light, and the generated light can be emitted from one side of the Micro-LED display device 10 to illuminate or display various information such as text, images, etc. For example, the Micro-LED display device 10 can be an LED display screen chip, an LED digital vehicle lamp chip, a digital lamp strip chip, an AR / VR / MR chip, etc.

[0030] As shown in FIG. 1, the Micro-LED display device 10 includes a display substrate 100 and a driving substrate 200 which are bonded in a stacked manner. The stacking direction of the display substrate 100 and the driving substrate 200 can be as shown by the A arrow in FIG. 1.

[0031] Specifically, the display substrate 100 can be defined with a plurality of display pixel points 101 along a vertical direction of a stacking direction A, and the plurality of display pixel points 101 can emit light under the driving of a driving current. The vertical direction of the stacking direction A can be as shown by the B arrow in FIG. 1. The driving substrate 200 can be configured to provide the driving current to each display pixel point 101 of the display substrate 100, so that the display substrate 100 can convert electrical energy into light energy to emit light.

[0032] As shown in FIG. 1, the display substrate 100 can include a light-emitting epitaxial layer 110 and a pixel electrode 120.

[0033] The light-emitting epitaxial layer 110 can include a first semiconductor layer 111, an active layer 112, and a second semiconductor layer 113, which are sequentially stacked along a stacking direction A of the display substrate 100 and the driving substrate 200.

[0034] Specifically, the first semiconductor layer 111 and the second semiconductor layer 113 are P-type semiconductor layers and N-type semiconductor layers, respectively, the active layer 112 is a plurality of quantum well layers, and the first semiconductor layer 111 and the second semiconductor layer 113 are located on both sides of the active layer 112 and in contact with the active layer 112. The active layer 112 can form an N-i-P structure together with the first semiconductor layer 111 and the second semiconductor layer 113 on both sides, and can emit light by recombination of electrons and holes, to form one or more display pixel points 101.

[0035] In some embodiments, the first semiconductor layer 111 and the second semiconductor layer 113 can be formed by doping semiconductor materials such as AlN, AlGaN, GaN, InGaN, AlInGaN, GaAs, GaP, GaInN, GaAsP, AlGaAs, AlGaInP, etc.

[0036] The pixel electrode 120 can be disposed on a side of the first semiconductor layer 111 away from the active layer 112 and in conductive connection with the first semiconductor layer 111. The pixel electrode 120 can be connected to the driving substrate 200 to transmit the driving current to the first semiconductor layer 111 as a P electrode of the first semiconductor layer 111.

[0037] Optionally, the number of pixel electrodes 120 can correspond to the display pixel points 101 in the light-emitting epitaxial layer 110. The number of pixel electrodes 120 can be a plurality, and the plurality of pixel electrodes 120 can correspond to the plurality of display pixel points 101 of the light-emitting epitaxial layer 110 one-to-one, so that the plurality of pixel electrodes 120 can respectively deliver the driving current to the plurality of display pixel points 101.

[0038] Optionally, the pixel electrode 120 can be a metal electrode with a certain reflectivity, for example, the pixel electrode 120 can be an electrode made of metal aluminum, silver or other conductive material. The pixel electrode 120 is provided with a certain reflectivity, so that the pixel electrode 120 can reflect the light generated in the display pixel point 101, so that the light can be concentrated on one side of the second semiconductor layer 113 and emitted, thereby improving the light collimation and light emitting efficiency of the Micro-LED display device 10.

[0039] As shown in FIG. 1, the driving substrate 200 can include a substrate body 210 and a plurality of power supply electrodes 220, which can be disposed on the substrate body 210 toward the first semiconductor layer 111. Among them, the plurality of power supply electrodes 220 can correspond one-to-one to the plurality of pixel electrodes 120 and the plurality of display pixel points 101, so as to provide driving current to each display pixel point 101.

[0040] Optionally, the plurality of power supply electrodes 220 can be electrodes made of metal copper, aluminum, silver, titanium, tungsten or other conductive materials. The inside of the substrate body 210 can be provided with related circuits and a plurality of switching devices (not shown in the figure) corresponding to each display pixel point 101. The plurality of power supply electrodes 220 are disposed on the substrate body 210 and electrically connected to the plurality of switching devices, so that the Micro-LED display device 10 can control the display and light emitting effect of a single pixel electrode 120 through the switching device. The substrate body 210 can be a CMOS (Complementary Metal Oxide Semiconductor) substrate.

[0041] Optionally, as shown in FIG. 1, the light emitting epitaxial layer 110 can be provided with a first via hole 114, which can penetrate the light emitting epitaxial layer 110. The Micro-LED display device 10 can further include a first metal column 300 filled in the first via hole 114. The first metal column 300 can be electrically insulated from the light emitting epitaxial layer 110 along the hole wall of the first via hole 114. The first metal column 300 is further fixedly connected with the power supply electrode 220 and forms a conductive path between the power supply electrode 220 and the pixel electrode 120.

[0042] Specifically, the surface of the power supply electrode 220 and the pixel electrode 120 can be exposed in the first via hole 114, so that the first metal column 300 can contact and communicate the power supply electrode 220 and the pixel electrode 120. Moreover, the first via hole 114 can be disposed in the region of the light emitting epitaxial layer 110 which is not the display pixel point 101, so that the setting of the first via hole 114 will not affect the display effect of each display pixel point 101.

[0043] Optionally, the first via hole 114 and the first metal column 300 can correspond to a plurality of display pixels 101, so that each display pixel 101 has a corresponding first via hole 114 and first metal column 300, and the plurality of first metal columns 300 can correspondingly connect the power supply electrode 220 and the pixel electrode 120 corresponding to each display pixel 101. Therefore, the pixel electrode 120 and the first metal column 300 can act as the P electrode of the light-emitting epitaxial layer 110 to drive the current to the first semiconductor layer 111.

[0044] In some embodiments, as shown in FIG. 1, the Micro-LED display device 10 can further include an insulating medium layer 400 arranged on the wall of the first via hole 114. The insulating medium layer 400 separates the first metal column 300 and the light-emitting epitaxial layer 110, so that the first metal column 300 and the light-emitting epitaxial layer 110 are electrically insulated, and thus the driving current transmitted by the first metal column 300 can be transmitted to the first semiconductor layer 111 through the pixel electrode 120, without being transmitted to the active layer 112 and the second semiconductor layer 113, thereby reducing the occurrence of current leakage and avoiding the occurrence of current crosstalk as much as possible, so that the Micro-LED display device 10 can emit light smoothly.

[0045] The insulating medium layer 400 can be an oxide layer made of silicon dioxide, silicon nitride or other insulating materials.

[0046] In other embodiments, other methods can also be used to keep the first metal column 300 and the light-emitting epitaxial layer 110 electrically insulated. For example, the light-emitting epitaxial layer 110 at the wall of the first via hole 114 can be provided with an insulating region formed by ion bombardment (not shown), so that the light-emitting epitaxial layer 110 at the wall of the first via hole 114 and the first metal column 300 in the first via hole 114 are self-electrically isolated to achieve the effect of insulation.

[0047] The arrangement of punching the light-emitting epitaxial layer 110 and filling the first metal column 300 to connect the power supply electrode 220 and the pixel electrode 120 can make the light-emitting epitaxial layer 110 and the driving substrate 200 connect the pixel electrode 120 and the power supply electrode 220 after bonding, so as to realize the interconnection of the pixel electrode 120 and the power supply electrode 220 after bonding. Therefore, the present application does not need to arrange a bonding electrode for connecting the power supply electrode 220 and the pixel electrode 120 at the bonding interface of the display substrate 100 and the driving substrate 200, and does not need to realize the interconnection of the electrodes at the same time during bonding, thereby reducing the bonding difficulty of the driving substrate 200 and the display substrate 100, simplifying the preparation process of the Micro-LED display device 10, and improving the yield of the Micro-LED display device 10.

[0048] In some embodiments, as shown in FIG. 1, the display substrate 100 can further include a first dielectric bonding layer 130 covering the pixel electrode 120, the driving substrate 200 can further include a second dielectric bonding layer 230 covering the power supply electrode 220, the first dielectric bonding layer 130 and the second dielectric bonding layer 230 can be bonded to each other, and the first via hole 114 can further penetrate the first dielectric bonding layer 130 and the second dielectric bonding layer 230.

[0049] The display substrate 100 and the driving substrate 200 are fixed to each other by the bonding of the first dielectric bonding layer 130 and the second dielectric bonding layer 230. Moreover, the first dielectric bonding layer 130 and the second dielectric bonding layer 230 can respectively fix the plurality of pixel electrodes 120 and the plurality of transfer electrodes 140, and act as a mask film and a protective layer to prevent impurities from diffusing into the display substrate 100 and the driving substrate 200.

[0050] Optionally, the first dielectric bonding layer 130 and the second dielectric bonding layer 230 can be oxide layers made of silicon dioxide, silicon nitride or other insulating materials.

[0051] In some embodiments, as shown in FIG. 1, the first via hole 114 can include a first hole segment 1141 and a second hole segment 1142 which are in communication with each other along the stacking direction A. The first hole segment 1141 can penetrate the light-emitting epitaxial layer 110, and the second hole segment 1142 can penetrate the first dielectric bonding layer 130 and the second dielectric bonding layer 230. The aperture of the first hole segment 1141 is larger than the aperture of the second hole segment 1142. The aperture of the first hole segment 1141 can be shown as the length R1 in FIG. 1, and the aperture of the second hole segment 1142 can be shown as the length R2 in FIG. 1, where R1 is greater than R2.

[0052] Optionally, as shown in FIG. 1, the first metal column 300 can include a first column segment 310 and a second column segment 320 which are connected to each other along the stacking direction A. The first column segment 310 is filled in the first hole segment 1141 and is conductively connected to the pixel electrode 120, and the second column segment 320 is filled in the second hole segment 1142 and is fixed and conductively connected to the power supply electrode 220.

[0053] Optionally, the end surface of the first column segment 310 is in contact with the main surface of the pixel electrode 120, and the end surface of the second column segment 320 is in contact with the main surface of the power supply electrode 220.

[0054] Specifically, the pixel electrode 120 contacts the first semiconductor layer 111 at a portion of the main surface of the light-emitting epitaxial layer 110, and another portion of the main surface is exposed in the first hole section 1141 and contacts the end surface of the first column section 310. Optionally, the insulating medium layer 400 can be arranged on the hole wall in the first hole section 1141 to separate the first column section 310 from the light-emitting epitaxial layer 110, so that the first column section 310 and the light-emitting epitaxial layer 110 are insulated from each other.

[0055] The power supply electrode 220 is exposed to the main surface of the display substrate 100 in the second hole section 1142, and the end surface of one end of the second column section 320 contacts the power supply electrode 220, and the end surface of the other end is exposed in the first hole diameter and contacts the end surface of the first column section 310. In this way, the power supply electrode 220 and the pixel electrode 120 can be conveniently connected in conductive communication through the second hole section 1142 and the first hole section 1141.

[0056] In this way, when the Micro-LED display device 10 is powered on and emits light, the current in the driving substrate 200 can flow through the power supply electrode 220, the second column section 320, the first column section 310, and the pixel electrode 120 to the first semiconductor layer 111 in the light-emitting epitaxial layer 110. Moreover, when the Micro-LED display device 10 is powered on and emits light, the display pixel point 101 in the Micro-LED display device 10 corresponds to the region of the light-emitting epitaxial layer 110 that is contacted by the portion of the main surface of the pixel electrode 120 that contacts the first semiconductor layer 111.

[0057] The first hole section 1141 has a larger hole diameter than the second hole section 1142, so that the hole diameter of the first column section 310 in the first hole section 1141 is larger than the hole diameter of the second column section 320 in the second hole section 1142, so that the first column section 310 can simultaneously contact the second column section 320 and the pixel electrode 120, thereby facilitating the connection between the power supply electrode 220 and the pixel electrode 120. Moreover, this arrangement also facilitates the punching or etching of the light-emitting epitaxial layer 110, the first medium bonding layer 130, and the second medium bonding layer 230 to form the first hole section 1141 and the second hole section 1142, thereby simplifying the processing technology of the Micro-LED display device 10.

[0058] In some embodiments, as shown in FIG. 1, the second column section 320 is spaced apart from the pixel electrode 120 along the radial direction of the second column section 320. The radial direction of the second column section 320 is perpendicular to the stacking direction A, and the radial direction of the second column section 320 is indicated by the B arrow in FIG. 1.

[0059] By setting the second column segment 320 to keep a predetermined interval with the pixel electrode 120 along the radial direction of the second column segment 320, the pixel electrode 120 can be prevented from being affected when forming the second hole segment 1142 and depositing the second column segment 320, so as to prevent the pixel electrode 120 from being damaged as much as possible.

[0060] In some other embodiments, the first column segment 310 can not be in direct contact with the pixel electrode 120 facing the main surface of the light-emitting epitaxial layer 110, so as to increase the contact area between the pixel electrode 120 and the first semiconductor layer 111.

[0061] Optionally, as shown in FIG. 2, the display substrate 100 can include a transfer electrode 140 disposed in the first dielectric bonding layer 130 and conductively connected with the pixel electrode 120. Wherein, on the side close to the first via hole 114, the transfer electrode 140 can extend beyond the pixel electrode 120 along the vertical direction of the stacking direction A, the first column segment 310 keeps a predetermined interval with the pixel electrode 120 along the radial direction of the first column segment 310, and the first column segment 310 is electrically connected with the pixel electrode 120 through the transfer electrode 140.

[0062] Optionally, the transfer electrode 140 can be an electrode made of metal copper, aluminum, silver, titanium, tungsten or other conductive materials.

[0063] Specifically, in this embodiment, the part of the transfer electrode 140 extending beyond the pixel electrode 120 also has the first dielectric bonding layer 130 between the transfer electrode 140 and the light-emitting epitaxial layer 110, so that the first via hole 114 not only penetrates the light-emitting epitaxial layer 110, but also penetrates part of the first dielectric bonding layer 130 beyond the light-emitting epitaxial layer 110, and part of the end surface of the transfer electrode 140 is exposed in the first via hole 114.

[0064] Optionally, the end surface of the first column segment 310 can be in contact with the main surface of the transfer electrode 140, the end surface of the second column segment 320 is in contact with the main surface of the power supply electrode 220, and the second column segment 320 keeps a predetermined interval with the pixel electrode 120 and the transfer electrode 140 along the radial direction of the second column segment 320. Therefore, when the Micro-LED display device 10 displays light, the current of the driving substrate 200 flows to the first semiconductor layer 111 of the light-emitting epitaxial layer 110 through the power supply electrode 220, the second column segment 320, the first column segment 310, the transfer electrode 140 and the pixel electrode 120 in turn.

[0065] The first column segment 310 is kept at a predetermined interval from the pixel electrode 120 in the radial direction of the first column segment 310 by the setting of the transfer electrode 140, so that the first column segment 310 is kept at a predetermined interval from the edge of the display pixel point 101 corresponding to the pixel electrode 120, thereby increasing the area of the display pixel point 101 corresponding to the pixel electrode 120, and preventing the pixel electrode 120 from being damaged when the first hole segment 1141 is formed by etching or punching the light-emitting epitaxial layer 110.

[0066] Optionally, as shown in FIG. 2, the transfer electrode 140 can include a first transfer electrode 141 and a second transfer electrode 142, the first transfer electrode 141 being arranged between the second transfer electrode 142 and the pixel electrode 120 and connecting the second transfer electrode 142 and the pixel electrode 120. The second transfer electrode 142 is arranged on the side of the first transfer electrode 141 away from the pixel electrode 120, and the second transfer electrode 142 extends beyond the pixel electrode 120 in the vertical direction of the stacking direction A on the side close to the first via hole 114. The first metal column 300 is in contact with and conductively connected to the second transfer electrode 142 through the first via hole 114.

[0067] In the stacking direction A, the length of the second transfer electrode 142 is greater than the length of the first transfer electrode 141. In this way, the first metal column 300 can be in conduction with the pixel electrode 120 through the second transfer electrode 142 with a longer length. The first transfer electrode 141 with a smaller length arranged between the second transfer electrode 142 and the pixel electrode 120 can facilitate the positioning of the pixel electrode 120, and can prevent the first transfer electrode 141 from blocking the contact between the first metal column 300 and the second transfer electrode 142.

[0068] In some embodiments, as shown in FIGS. 1 and 2, the display substrate 100 can further include a dielectric planar layer 150 covering the side of the second semiconductor layer 113 away from the active layer 112, and the dielectric planar layer 150 can be provided with a second via hole 151 penetrating the dielectric planar layer 150. The Micro-LED display device 10 can further include a second metal column 500 filled in the second via hole 151, and the second metal column 500 is in conductive connection with the second semiconductor layer 113.

[0069] Specifically, the second via hole 151 penetrates the dielectric planar layer 150, the second semiconductor layer 113 is exposed at the bottom of the second via hole 151, the second metal column 500 fills the second via hole 151 and is in contact with the second semiconductor layer 113 exposed in the second via hole 151, and the second metal column 500 is in conductive connection with the second semiconductor layer 113.

[0070] The second metal column 500 can provide current voltage for the display pixel point 101 as the N electrode of the display pixel point 101. Specifically, under the voltage driving of the second metal column 500, the current provided by the second metal column 500 can realize lateral current diffusion in the second semiconductor layer 113, so that the current of the second metal column 500 can be diffused into the second semiconductor layer 113 corresponding to the plurality of display pixel points 101, so that the plurality of display pixel points 101 can realize composite light emission.

[0071] Optionally, as shown in FIG. 3, the second via hole 151 can present a grid shape when viewed along the stacking direction A, and thus the second metal column 500 also presents a grid shape. The grid-shaped second metal column 500 can facilitate the transmission of current to each display pixel point 101, thereby reducing the loss caused by current propagation and diffusion, and enhancing the display and light emission efficiency of the Micro-LED display device 10.

[0072] Moreover, as shown in FIG. 2, the projection of the region of the second via hole 151 and the second metal column 500 along the stacking direction A and the projection of the display pixel point 101 are staggered with each other, and also staggered with the projection of the first metal column 300, so that the light emitted by the display pixel point 101 is not easily blocked by the second metal column 500 in the second via hole 151, and the second metal column 500 will not be in direct contact with the first metal column 300 to cause a short circuit phenomenon.

[0073] Optionally, the dielectric flat layer 150 can be prepared from a transparent and insulating material, for example, the dielectric flat layer 150 can be prepared from an insulating material such as silicon dioxide and silicon nitride. The transparent and insulating dielectric flat layer 150 not only can not affect the smooth transmission of light in the display pixel point 101, but also will not cause a short circuit phenomenon due to the electrical conduction between the second metal column 500 and the first metal column 300. The second metal column 500 can be prepared from a conductive metal such as copper, titanium, and silver.

[0074] By arranging the dielectric flat layer 150 to cover the side of the light-emitting epitaxial layer 110 opposite to the driving substrate 200, the surface of the Micro-LED display device 10 can be made more flat, and the Micro-LED display device 10 can be facilitated to add other processes subsequently, so as to improve the yield of the Micro-LED display device 10.

[0075] In some embodiments, the second metal column 500 can be connected to an external circuit outside the Micro-LED display device 10, and the external circuit thus provides current voltage to the second semiconductor layer 113 through the second metal column 500.

[0076] In some embodiments, as shown in FIG. 1 and FIG. 2, the side of the light-emitting epitaxial layer 110 opposite to the driving substrate 200 can be processed to lead out the electrodes of the driving substrate 200 from the side of the light-emitting epitaxial layer 110 opposite to the driving substrate 200, so as to facilitate the external circuit to connect the driving substrate 200.

[0077] Optionally, as shown in FIG. 1 and FIG. 2, the driving substrate 200 can be provided with a driving electrode 240, the driving electrode 240 is disposed on the substrate body 210, and the substrate body 210 can be provided with internal lead wires connecting the driving electrode 240 and the plurality of power supply electrodes 220. The Micro-LED display device 10 has a third via hole 600 penetrating the light-emitting epitaxial layer 110, the first dielectric bonding layer 130 and the second dielectric bonding layer 230, and a main surface of the driving electrode 240 is exposed in the third via hole 600. The Micro-LED display device 10 further includes a third metal column 700 filled in the third via hole 600, one end of the third metal column 700 is in contact with the driving electrode 240, and the other end is exposed on the surface of the light-emitting epitaxial layer 110.

[0078] Optionally, as shown in FIG. 1 and FIG. 2, the dielectric planar layer 150 can include a fourth via hole 152, and the Micro-LED display device 10 further includes a fourth metal column 800 filled in the fourth via hole 152, the fourth metal column 800 is in contact with the third metal column 700 and is in communication with the third metal column 700 to communicate the driving electrode 240 through the third metal column 700, so as to lead out the electrodes of the driving substrate 200 from the surface of the dielectric planar layer 150, so as to facilitate the external circuit to connect the driving substrate 200 through the fourth metal column 800 on the surface of the dielectric planar layer 150.

[0079] Optionally, the third metal column 700 and the fourth metal column 800 can be electrodes made of metal copper, aluminum, silver, titanium, tungsten or other materials with conductivity.

[0080] Optionally, the projection of the third metal column 700 and the driving electrode 240 along the stacking direction A is staggered with the projection of each pixel electrode 120, so that the third metal column 700 does not block the light-emitting area of the display pixel point 101 in the light-emitting epitaxial layer 110.

[0081] Optionally, the third metal column 700 and the light-emitting epitaxial layer 110 can be electrically insulated. Optionally, the hole wall of the third via hole 600 also has an insulating dielectric layer 400, which separates the third metal column 700 and the light-emitting epitaxial layer 110. Alternatively, other ways can be used to keep the third metal column 700 and the light-emitting epitaxial layer 110 electrically insulated. For example, the light-emitting epitaxial layer 110 at the hole wall of the third via hole 600 can be provided with an insulating area formed by ion bombardment (not shown in the figure).

[0082] Optionally, the fourth via hole 152 can include a third hole section 1521 and a fourth hole section 1522, and the fourth metal column 800 can include a first metal section 810 filled in the third hole section 1521 and a second metal section 820 filled in the fourth hole section 1522. Wherein, in the vertical direction along the stacking direction A, the length of the second metal section 820 is greater than the length of the first metal section 810.

[0083] Specifically, the first metal section 810 is arranged between the third metal column 700 and the second metal section 820, and respectively contacts and communicates the second metal section 820 and the third metal column 700. One end of the second metal section 820 contacts and communicates with the first metal section 810, and the other end of the second metal section 820 opposite to the first metal section 810 is exposed on the surface of the medium planar layer 150.

[0084] By setting the length of the second metal section 820 exposed on the surface of the medium planar layer 150 to be relatively long, it is convenient for the external circuit to be connected with the second metal section 820 by wire bonding packaging, so as to facilitate the connection of the external circuit with the driving substrate 200 and the power supply to the driving substrate 200. Moreover, by setting the length of the first metal section 810 contacting the third metal column 700 to be relatively small, the first metal section 810 is not easy to contact the light-emitting epitaxial layer 110 beyond the third metal column 700, so as to reduce the phenomenon of electric leakage circuit.

[0085] Based on the structure of the Micro-LED display device 10, the preparation method of the Micro-LED display device 10 is exemplarily described as follows, as shown in FIGS. 4 to 9. FIG. 4 is a flow chart of the preparation method of an embodiment of the Micro-LED display device, and FIGS. 5 to 9 show the preparation process and component structure involved in the flow steps shown in FIG. 4. The preparation method of the Micro-LED display device 10 can include the following steps:

[0086] S100: providing a display substrate and a driving substrate bonded with each other in a stacking manner, wherein the display substrate includes a light-emitting epitaxial layer and a pixel electrode, the light-emitting epitaxial layer includes a first semiconductor layer, an active layer and a second semiconductor layer arranged in sequence in a stacking direction of the display substrate and the driving substrate, the pixel electrode is arranged on a side of the first semiconductor layer away from the active layer and is in conductive connection with the first semiconductor layer, and the driving substrate includes a substrate body and a plurality of power supply electrodes arranged on a side of the substrate body facing the first semiconductor layer.

[0087] Optionally, this step can correspond to FIGS. 5 and 6. Therefore, the step S100 can include steps S111 to S114:

[0088] S111: providing a substrate, sequentially growing a second semiconductor layer, an active layer, and a first semiconductor layer on the substrate.

[0089] A substrate 20 is provided, and a second semiconductor layer 113, an active layer 112, and a first semiconductor layer 111 are sequentially generated on the substrate 20. The substrate 20 can be made of sapphire, silicon, gallium nitride, aluminum nitride, or the like, which is not limited in the embodiment.

[0090] S112: growing a pixel electrode layer on the side of the first semiconductor layer opposite to the active layer, etching the pixel electrode layer to form a plurality of pixel electrodes, and then covering the plurality of pixel electrodes 120 with a first dielectric bonding layer on the side opposite to the light-emitting epitaxial layer.

[0091] Optionally, a pixel electrode layer 121 is arranged on the side of the first semiconductor layer 111 opposite to the substrate 20. Then, the distance between the plurality of display pixels 101 can be calculated according to the required distance of the plurality of display pixels 101 of the Micro-LED display device 10, and the pixel electrode layer 121 is etched according to the distance, and then a wet or dry etching process is performed to obtain a plurality of pixel electrodes 120 arranged in an array.

[0092] Optionally, a first dielectric bonding layer 130 is grown on the side of the light-emitting epitaxial layer 110 opposite to the plurality of pixel electrodes 120, and the first dielectric bonding layer 130 covers the plurality of pixel electrodes 120 and the first semiconductor layer 111 on the side of the light-emitting epitaxial layer 110.

[0093] S113: providing a substrate body with a plurality of power supply electrodes, and further covering the substrate body with a second dielectric bonding layer on the side of the substrate body provided with the power supply electrodes.

[0094] S114: inverting the display substrate on the driving substrate to realize the alignment and connection of the display substrate and the driving substrate in a manner that the first dielectric bonding layer faces the second dielectric bonding layer.

[0095] Specifically, the display substrate 100 is inverted on the driving substrate 200, wherein the positions of the power supply electrodes 220 and the pixel electrodes 120 are misaligned to prepare for the formation of the first via hole 114.

[0096] Then, the first dielectric bonding layer 130 and the second dielectric bonding layer 230 can be bonded to each other by fusion bonding, i.e., the two are fused and bonded to each other by mechanical force and high temperature.

[0097] Alternatively, other bonding methods can also be used to bond the first die bonding layer 130 and the second die bonding layer 230 to each other. For example, the surfaces of the first die bonding layer 130 and the second die bonding layer 230 can be plasma-activated or chemically treated, and then the display substrate 100 is inverted on the driving substrate 200 with the first die bonding layer 130 facing the second die bonding layer 230. After alignment, a certain pressure is applied to the first die bonding layer 130 and the second die bonding layer 230 to achieve diffusion fusion, thereby achieving high-strength connection and fixation of the display substrate 100 and the driving substrate 200.

[0098] Of course, the first die bonding layer 130 and the second die bonding layer 230 can also be bonded by adhesive bonding, anodic bonding, etc., which are not specifically limited in the present embodiment.

[0099] Further, after the bonding connection of the display substrate 100 and the driving substrate 200 is completed, the removal substrate 20 can be removed by grinding, chemical etching, or laser lift-off (LLO) process, so that the second semiconductor layer 113 is exposed.

[0100] S200: Forming a first via hole penetrating the light-emitting epitaxial layer from the side of the light-emitting epitaxial layer away from the driving substrate.

[0101] Optionally, this step can correspond to FIG. 7, and this step can include step S210:

[0102] S210: Forming a first hole section penetrating the light-emitting epitaxial layer and a second hole section penetrating the first die bonding layer and the second die bonding layer, wherein the first hole section and the second hole section communicate with each other along the stacking direction A, and the aperture of the first hole section is smaller than the aperture of the second hole section.

[0103] Specifically, the light-emitting epitaxial layer 110 can be etched first on the side of the light-emitting epitaxial layer 110 facing away from the driving substrate 200, thereby forming a plurality of first hole sections 1141 in the light-emitting epitaxial layer 110. The plurality of first hole sections 1141 correspond one-to-one to the plurality of pixel electrodes 120. The main surface of each pixel electrode 120 for contacting the first semiconductor layer 111 is partially exposed to the bottom of the corresponding first hole section 1141. The bottom wall of the first hole section 1141 also exposes the first die bonding layer 130.

[0104] Further, the first die bonding layer 130 of the bottom wall of the first hole segment 1141 is etched in the plurality of first hole segments 1141, and the first die bonding layer 130 and the second die bonding layer 230 are further etched through to form a second hole segment 1142 in communication with the first hole segment 1141, wherein the bottom wall of the second hole segment 1142 exposes the power supply electrode 220. The second hole segment 1142 and the first hole segment 1141 form a first via hole 114.

[0105] The end of the second hole segment 1142 close to the pixel electrode 120 is kept a predetermined interval from the pixel electrode 120, so that the second hole segment 1142 will not damage the pixel electrode 120 during etching, and the pixel electrode 120 will not be exposed in the second hole segment 1142.

[0106] S300: filling a first metal column in the first via hole, wherein the first metal column is electrically insulated from the light-emitting epitaxial layer along the hole wall of the first via hole, and the first metal column is further fixedly connected to the power supply electrode and forms a conductive path between the power supply electrode and the pixel electrode.

[0107] Optionally, this step can correspond to Figure 7. Further, this step can include the following steps S311-S312:

[0108] S311: processing the hole wall of the first via hole.

[0109] The first metal column 300 needs to be electrically insulated from the light-emitting epitaxial layer 110 along the hole wall of the first via hole 114, so in some embodiments, an insulating dielectric layer 400 can be first provided on the hole wall of the first via hole 114, and then the first metal column 300 is filled. Or in other embodiments, the light-emitting epitaxial layer 110 corresponding to the hole wall of the first via hole 114 can be directly ion sputtered to form an insulating region (not shown) corresponding to the region of the first via hole 114, of course, there are other insulation methods, which will not be specifically enumerated one by one in this embodiment.

[0110] S312: forming a first column segment filled in the first hole segment and a second column segment filled in the second hole segment, wherein the first column segment and the second column segment are connected to each other along the stacking direction, the first column segment is conductively connected to the pixel electrode, and the second column segment is fixedly and conductively connected to the power supply electrode.

[0111] Specifically, the second column segment 320 can be first filled and deposited in the second hole segment 1142, and after the formation of the second column segment 320, one end surface of the second column segment 320 can be in fixed contact with the power supply electrode 220, and the other end surface is exposed at the bottom of the first hole segment 1141.

[0112] Further, the first column segment 310 is filled in the first hole segment 1141, and the bottom of the first column segment 310 contacts the second column segment 320 and the pixel electrode 120 to connect the second column segment 320 and the pixel electrode 120. The top of the first column segment 310 is exposed at the end of the light emitting epitaxial layer 110 away from the driving substrate 200. Optionally, the side of the first column segment 310 away from the second column segment 320 is flush with the side of the light emitting epitaxial layer 110 away from the driving substrate 200.

[0113] In some embodiments, if the driving electrode 240 can be provided in the driving substrate 200 and needs to be led out of the side of the light emitting epitaxial layer 110 away from the driving substrate 200, step S400 can be provided after step S310 to lead out the driving electrode 240:

[0114] S400: Form a third via hole penetrating the light emitting epitaxial layer, the first dielectric bonding layer and the second dielectric bonding layer at the position corresponding to the driving electrode, and then fill a third metal column in the third via hole, wherein the first metal column is electrically insulated from the light emitting epitaxial layer along the hole wall of the first via hole.

[0115] Optionally, this step can refer to FIG. 8.

[0116] Specifically, on the side of the light emitting epitaxial layer 110 away from the driving substrate 200 and at the position corresponding to the driving electrode 240 in the driving substrate 200, the light emitting epitaxial layer 110, the first dielectric bonding layer 130 and the second dielectric bonding layer 230 are etched to form a third via hole 600. The end surface of the driving electrode 240 facing the light emitting epitaxial layer 110 is exposed in the third via hole 600.

[0117] Further, the hole wall of the third via hole 600 can be processed, for example, an insulating dielectric layer 400 can be provided on the hole wall of the third via hole 600. Alternatively, the light emitting epitaxial layer 110 at the hole wall of the third via hole 600 can be ion bombarded to form an insulating region (not shown).

[0118] Then, a third metal column 700 is filled in the third via hole 600, one end of the third metal column 700 contacts and electrically communicates with the driving electrode 240, and the other end is exposed at the end of the light emitting epitaxial layer 110 away from the driving substrate 200.

[0119] In some embodiments, if the display substrate 100 further includes a dielectric planar layer 150 covering the side of the second semiconductor layer 113 away from the active layer 112 and a second metal column 500 provided on the dielectric planar layer 150, step S500 can be added after S400:

[0120] S500: covering the light-emitting epitaxial layer on the side opposite to the driving substrate with a dielectric planar layer, etching the dielectric planar layer to form a second via and a fourth via penetrating the dielectric planar layer, and then filling the second via with a second metal column and filling the fourth via with a fourth metal column.

[0121] Specifically, the dielectric planar layer 150 covers the light-emitting epitaxial layer 110, the first metal column 300 and the third metal column 700 on the side of the light-emitting epitaxial layer 110 opposite to the driving substrate 200.

[0122] Then, the dielectric planar layer 150 is etched in the region corresponding to the non-display pixel point 101 and the non-first metal column 300 to form a second via 151. The second via 151 exposes the second semiconductor layer 113. When viewed along the stacking direction A of the display substrate 100 and the driving substrate 200, the second via 151 appears in a grid shape.

[0123] Further, the second metal column 500 is filled in the second via 151, and the second metal column 500 contacts the second semiconductor layer 113 to communicate the second semiconductor layer 113. The second metal column 500 appears in a grid shape.

[0124] The dielectric planar layer 150 is etched in the region corresponding to the third metal column 700 to form a fourth hole segment 1522, and the dielectric planar layer 150 is further etched at the bottom of the fourth hole segment 1522 to form a third hole segment 1521. The fourth hole segment 1522 and the third hole segment 1521 together form a fourth via 152. The length of the fourth hole segment 1522 is greater than the length of the third hole segment 1521. The third metal column 700 is exposed at the bottom of the third hole segment 1521.

[0125] Further, the first metal segment 810 is filled in the third hole segment 1521, and the first metal segment 810 contacts and electrically communicates with the third metal column 700. Then, the second metal segment 820 is filled in the fourth hole segment 1522, one end of the second metal segment 820 contacts the first metal segment 810 to communicate the third metal column 700, and the other end is exposed on the surface of the dielectric planar layer 150 and flush with the surface of the dielectric planar layer 150. The first metal segment 810 and the second metal segment 820 together form a fourth metal column 800.

[0126] In some other embodiments, if the display substrate 100 includes a transfer electrode 140 disposed in the first dielectric bonding layer 130 and electrically connected with the pixel electrode 120, the preparation method of the Micro-LED display device 10 in this embodiment can be improved with reference to the preparation method described above to obtain a new preparation method.

[0127] As shown in FIGS. 10-14, FIG. 10 is a flowchart of a method for manufacturing a Micro-LED display device according to another embodiment of the present application, and FIGS. 11-14 show the manufacturing process and component structure involved in the steps shown in FIG. 10. Specifically, the Micro-LED display device 10 in this embodiment can include step S111, followed by steps S121-S122:

[0128] S121: growing a pixel electrode layer on the side of the first semiconductor layer opposite to the active layer, etching the pixel electrode layer to form a plurality of pixel electrodes, and then covering the side of the plurality of pixel electrodes opposite to the light-emitting epitaxial layer with a first sub-medium bonding layer.

[0129] Optionally, referring to FIG. 11, a pixel electrode layer 121 can be provided on the side of the first semiconductor layer 111 opposite to the substrate 20. Then, the distance between the plurality of display pixels 101 can be calculated according to the required distance of the plurality of display pixels 101 of the Micro-LED display device 10, and the pixel electrode layer 121 can be etched according to the distance, and then a wet or dry etching process can be performed to obtain a plurality of pixel electrodes 120 arranged in an array.

[0130] Optionally, referring to FIG. 11, a first sub-medium bonding layer 131 can be grown on the side of the light-emitting epitaxial layer 110 opposite to the plurality of pixel electrodes 120, and the first medium bonding layer 130 covers the plurality of pixel electrodes 120 and the first semiconductor layer 111 on the side of the light-emitting epitaxial layer 110.

[0131] S122: etching the first sub-medium bonding layer on the side of the first sub-medium bonding layer opposite to the plurality of pixel electrodes to form a plurality of through holes, adding a plurality of transfer electrodes in the plurality of through holes, and covering the side of the plurality of transfer electrodes opposite to the light-emitting epitaxial layer with a second sub-medium bonding layer, wherein the first sub-medium bonding layer and the second sub-medium bonding layer together form a first medium bonding layer.

[0132] Specifically, referring to FIG. 11, the first sub-medium bonding layer 131 can be etched on the side of the first sub-medium bonding layer 131 opposite to the plurality of pixel electrodes 120 to form a plurality of large through holes 1311, and further etching at the bottom of the large through holes 1311 to form a plurality of small through holes 1312. One surface of the pixel electrode 120 is exposed in the small through hole 1312.

[0133] Further, the first transfer electrodes 141 are filled in the plurality of small via holes 1312, and the first transfer electrodes 141 are in contact with and electrically connected to the corresponding pixel electrodes 120. The end surface of the first transfer electrodes 141 is exposed to the bottom of the large via hole 1311. Then, the second transfer electrodes 142 are filled in the plurality of large via holes 1311, and the second transfer electrodes 142 are in contact with and electrically connected to the corresponding first transfer electrodes 141. The first transfer electrodes 141 and the second transfer electrodes 142 form the transfer electrodes 140. The second transfer electrodes 142 can extend beyond the pixel electrodes 120 in the direction perpendicular to the stacking direction A.

[0134] Further, as shown in FIG. 11, a second sub dielectric bonding layer 132 is arranged on the side of the second transfer electrodes 142 opposite to the first transfer electrodes 141. The second sub dielectric bonding layer 132 covers the first sub dielectric bonding layer 131 and the second transfer electrodes 142. The second sub dielectric bonding layer 132 and the first sub dielectric bonding layer 131 together form the first dielectric bonding layer 130.

[0135] In other embodiments, after the plurality of pixel electrodes 120 are formed, the plurality of transfer electrodes 140 can be directly arranged to be fixedly connected to the plurality of pixel electrodes 120. Then, the first dielectric bonding layer 130 is filled in the plurality of transfer electrodes 140 and the plurality of pixel electrodes 120, and the first dielectric bonding layer 130 further covers the side of the plurality of transfer electrodes 140 opposite to the plurality of pixel electrodes 120.

[0136] After step S122, the driving substrate 200 can be arranged, and the display substrate 100 is bonded to the driving substrate 200. Therefore, the preparation method of the Micro-LED display device 10 in the present embodiment can further include steps S113-S114 described above, and can refer to FIG. 12. The specific description of steps S113-S114 can be found in the above description, and will not be repeated here.

[0137] After step S114, the preparation method of the Micro-LED display device 10 in the present embodiment can include the following steps:

[0138] S220: Forming a first via hole penetrating the light-emitting epitaxial layer from the side of the light-emitting epitaxial layer away from the driving substrate, wherein the first via hole is kept a predetermined interval from the pixel electrode.

[0139] Optionally, this step can refer to FIG. 13.

[0140] Specifically, the light emitting epitaxial layer 110 can be etched on the side of the light emitting epitaxial layer 110 opposite to the driving substrate 200, and a plurality of first hole segments 1141 corresponding to the plurality of second transfer electrodes 142 are formed in the light emitting epitaxial layer 110. The first hole segment 1141 penetrates the light emitting epitaxial layer 110, and the bottom of the first hole segment 1141 can expose the surface of the second transfer electrode 142 and the first dielectric bonding layer 130.

[0141] Further, the first dielectric bonding layer 130 on the bottom wall of the first hole segment 1141 in the plurality of first hole segments 1141 is etched, and the first dielectric bonding layer 130 and the second dielectric bonding layer 230 are further etched to form a second hole segment 1142 in communication with the first hole segment 1141, and the second hole segment 1142 and the first hole segment 1141 form a first via hole 114. The bottom wall of the second hole segment 1142 exposes the power supply electrode 220.

[0142] The end of the second hole segment 1142 close to the pixel electrode 120 is kept at a predetermined interval from the pixel electrode 120, so that the second hole segment 1142 will not damage the pixel electrode 120 during etching, and the pixel electrode 120 will not be exposed in the second hole segment 1142.

[0143] S320: filling a first metal column in the first via hole, wherein the first metal column is electrically insulated from the light emitting epitaxial layer along the hole wall of the first via hole, the first metal column is further fixedly connected with the power supply electrode, and forms a conductive path between the power supply electrode and the pixel electrode.

[0144] Optionally, this step can refer to FIG. 13.

[0145] Specifically, the hole wall of the first via hole 114 can be first insulated, and the specific processing flow can refer to step S311, which will not be repeated here.

[0146] Further, the second column segment 320 can be first filled in the second hole segment 1142, and after the formation of the second column segment 320, one end surface of the second column segment 320 can be in fixed contact with the power supply electrode 220, and the other end surface is exposed at the bottom of the first hole segment 1141.

[0147] Further, the first column segment 310 is filled in the first hole segment 1141, and the bottom of the first column segment 310 contacts the second column segment 320 and the second transfer electrode 142 to communicate the second column segment 320 and the second transfer electrode 142. The top of the first column segment 310 is exposed at the end of the light-emitting epitaxial layer 110 away from the driving substrate 200. Wherein the first column segment 310 is arranged to maintain a predetermined interval with the pixel electrode 120 along the radial direction of the first column segment 310 and is electrically connected to the pixel electrode 120 through the transfer electrode 140. The first column segment 310 and the second column segment 320 form the first metal column 300.

[0148] After the first metal column 300 is set, the preparation method of the Micro-LED display device 10 in the embodiment can also lead out the driving electrode 240 of the driving substrate 200 from the side of the light-emitting epitaxial layer 110 away from the driving substrate 200. The dielectric flat layer 150 and the second metal column 500 can also be arranged on the side of the second semiconductor layer 113 away from the active layer 112. Therefore, the embodiment can include steps S400-S500 after step S320. The specific operations can refer to the textual description of steps S400-S500 and FIG. 14. The steps S400-S500 can be seen from the above description, and the embodiment will not be repeated here.

[0149] Through the above preparation method, the preparation process of the Micro-LED display device 10 can be simplified, and the bonding difficulty of the Micro-LED display device 10 can be reduced.

[0150] Of course, in other embodiments, other functional layers can also be added to the Micro-LED display device 10. For example, a mirror can be arranged on the side of the dielectric flat layer 150 away from the light-emitting epitaxial layer 110, and the reflectivity of the mirror is less than the reflectivity of the pixel electrode 120, so that a resonant cavity is formed between the pixel electrode 120 and the mirror to emit light from the side of the mirror, thereby improving the light-emitting efficiency of the Micro-LED display device 10. Alternatively, a wavelength conversion layer can also be added to the side of the dielectric flat layer 150 away from the light-emitting epitaxial layer 110 to change the color of the light of the display pixel point 101 of the Micro-LED display device 10. Alternatively, the functional layer can also include other element layers such as a microlens array layer, and the embodiment will not be specifically enumerated one by one here.

[0151] In summary, the application forms the first via hole 114 by punching in the light-emitting epitaxial layer 110 and sets the first metal column 300 in the first via hole 114. The first metal column 300 penetrates the light-emitting epitaxial layer 110 and is in contact with the pixel electrode 120 and the power supply electrode 220 in the driving substrate 200. Therefore, a conductive path is formed between the power supply electrode 220 and the pixel electrode 120. Therefore, the setting of the first metal column 300 can make the display substrate 100 and the driving substrate 200 not need to set the electrode bonding between the two to electrically connect the pixel electrode 120 and the power supply electrode 220. Therefore, the bonding difficulty of the driving substrate 200 and the display substrate 100 can be reduced, thereby simplifying the preparation process of the Micro-LED display device 10.

[0152] The above is only an embodiment of the application, and does not limit the patent scope of the application. Any equivalent structure or equivalent flow transformation using the content of the specification and drawings, or direct or indirect application in other related technical fields, is also included in the patent protection scope of the application.

Claims

1. A Micro-LED display device, characterized in that, The Micro-LED display device includes a display substrate and a driving substrate bonded to each other in a laminated manner, the display substrate includes a light-emitting epitaxial layer and a pixel electrode, the light-emitting epitaxial layer includes a first semiconductor layer, an active layer and a second semiconductor layer arranged in a laminated manner along a laminating direction of the display substrate and the driving substrate, the pixel electrode is arranged on a side of the first semiconductor layer away from the active layer and is in conductive connection with the first semiconductor layer, the driving substrate includes a substrate body and a plurality of power supply electrodes arranged on a side of the substrate body facing the first semiconductor layer, the light-emitting epitaxial layer is provided with a first via hole penetrating through the light-emitting epitaxial layer, and the Micro-LED display device further includes a first metal column filled in the first via hole, the first metal column is in electrical insulation with the light-emitting epitaxial layer along a hole wall of the first via hole, the first metal column is further fixedly connected with the power supply electrode and forms a conductive path between the power supply electrode and the pixel electrode. 2.The Micro-LED display device of claim 1, wherein, The display substrate further includes a first dielectric bonding layer covering the pixel electrode, the driving substrate further includes a second dielectric bonding layer covering the power supply electrode, the first dielectric bonding layer and the second dielectric bonding layer are bonded to each other, and the first via hole further penetrates through the first dielectric bonding layer and the second dielectric bonding layer.

3. The Micro-LED display device of claim 2, wherein, The first via hole includes a first hole section and a second hole section in communication with each other along the laminating direction, the first hole section penetrates through the light-emitting epitaxial layer, the second hole section penetrates through the first dielectric bonding layer and the second dielectric bonding layer, an aperture of the first hole section is larger than an aperture of the second hole section, and the first metal column includes a first column section and a second column section connected to each other along the laminating direction, wherein the first column section is filled in the first hole section and is in conductive connection with the pixel electrode, and the second column section is filled in the second hole section and is fixedly and conductively connected with the power supply electrode.

4. The Micro-LED display device of claim 3, wherein, The second column section is in a predetermined interval with the pixel electrode along a radial direction of the second column section.

5. The Micro-LED display device of claim 3, wherein, An end surface of the first column section is in contact with a main surface of the pixel electrode, and an end surface of the second column section is in contact with a main surface of the power supply electrode. 6.The Micro-LED display device of claim 3, wherein, The display substrate includes a transfer electrode arranged in the first dielectric bonding layer and in conductive connection with the pixel electrode, and on a side close to the first via hole, the transfer electrode exceeds the pixel electrode along a vertical direction of the laminating direction, the first column section is in a predetermined interval with the pixel electrode along a radial direction of the first column section and is electrically connected with the pixel electrode through the transfer electrode.

7. The Micro-LED display device of claim 6, wherein, An end surface of the first column section is in contact with a main surface of the transfer electrode, and an end surface of the second column section is in contact with a main surface of the power supply electrode, and the second column section is in a predetermined interval with the pixel electrode and the transfer electrode along a radial direction of the second column section. 8.The Micro-LED display device of claim 1, wherein, The display substrate further comprises a dielectric planar layer covering the second semiconductor layer away from the active layer, the dielectric planar layer is provided with a second via hole penetrating through the dielectric planar layer, and the Micro-LED display device further comprises a second metal column filled in the second via hole and electrically connected with the second semiconductor layer.

9. A preparation method of a Micro-LED display device, characterized in that, The method comprises: providing a display substrate and a driving substrate bonded in a stacked manner, wherein the display substrate comprises a light-emitting epitaxial layer and a pixel electrode, the light-emitting epitaxial layer comprises a first semiconductor layer, an active layer and a second semiconductor layer sequentially stacked in a stacking direction of the display substrate and the driving substrate, the pixel electrode is arranged on a side of the first semiconductor layer away from the active layer and is electrically connected with the first semiconductor layer, and the driving substrate comprises a substrate body and a plurality of power supply electrodes arranged on a side of the substrate body facing the first semiconductor layer; forming a first via hole penetrating through the light-emitting epitaxial layer from a side of the light-emitting epitaxial layer away from the driving substrate; filling a first metal column in the first via hole, wherein the first metal column is electrically insulated from the light-emitting epitaxial layer along a hole wall of the first via hole, the first metal column is further fixedly connected with the power supply electrode and forms an electrically conductive path between the power supply electrode and the pixel electrode.

10. The method of claim 9, wherein, The display substrate further comprises a first dielectric bonding layer covering the pixel electrode, and the driving substrate further comprises a second dielectric bonding layer covering the power supply electrode, and the first dielectric bonding layer and the second dielectric bonding layer are bonded with each other; The first via hole penetrating through the light-emitting epitaxial layer from the side of the light-emitting epitaxial layer away from the driving substrate comprises: forming a first hole section penetrating through the light-emitting epitaxial layer and a second hole section penetrating through the first dielectric bonding layer and the second dielectric bonding layer, wherein the first hole section and the second hole section are communicated with each other in the stacking direction, and an aperture of the first hole section is smaller than an aperture of the second hole section; The first metal column filled in the first via hole comprises: forming a first column section filled in the first hole section and a second column section filled in the second hole section, wherein the first column section and the second column section are connected with each other in the stacking direction, the first column section is electrically connected with the pixel electrode, and the second column section is fixedly and electrically connected with the power supply electrode.

11. The method of claim 10, wherein, The display substrate comprises a transfer electrode arranged in the first dielectric bonding layer and electrically connected with the pixel electrode; The first metal column filled in the first via hole comprises: arranging the first column section to maintain a predetermined interval with the pixel electrode in a radial direction of the first column section and electrically connecting the pixel electrode through the transfer electrode.

Images