Micro light-emitting diode substrate and manufacturing method thereof

Abstract

The invention discloses a micro light-emitting diode substrate and a manufacturing method thereof. The micro light-emitting diode substrate comprises a substrate, a driving circuit layer, a plurality of micro light-emitting diodes, a plurality of connecting via holes and a plurality of conductive structures. The driving circuit layer is located on the first side of the substrate, the micro light-emitting diodes are located on the second side of the substrate, the second side and the first side are the two opposite sides of the substrate, the connecting via holes penetrate through the substrate, and the conductive structures are located in the connecting via holes and correspond to the connecting via holes in a one-to-one mode. The plurality of connection via holes comprise a plurality of first connection via holes, the plurality of conductive structures comprise a plurality of first conductive structures, the plurality of first conductive structures are located in the plurality of first connection via holes, and the plurality of micro light emitting diodes are electrically connected with the driving circuit layer through the plurality of first conductive structures. The driving circuit layer and the micro light-emitting diodes are located on the two sides of the substrate, seamless splicing can be achieved, the repair yield can be improved, and the growth of foreign matter on the substrate does not affect light emitting or display.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to a micro light emitting diode substrate and a method for manufacturing the same. Background Art

[0002] Liquid Crystal Display (LCD) is the earliest popular and most mature display technology. Organic Light-Emitting Diode (OLED) display technology is a new generation of display technology after LCD, and the technology is already very mature.

[0003] In recent years, with the rapid development of the micro-light emitting diode (MLED) industry, the application of micro-light emitting diodes has become more and more extensive. Micro-light emitting diodes include sub-millimeter light emitting diodes (Mini Light Emitting Diode, Mini LED) and micro light emitting diodes (Micro Light Emitting Diode, Micro LED). Micro-light emitting diodes have excellent performance such as lower power consumption, faster response, longer life, higher color saturation and contrast. With technological breakthroughs, Mini LED and Micro LED displays will become the next generation of display technology after LCD and OLED. With the popularization of 4K ultra-high definition in the 5G era, it is expected that Mini LED and Micro LED panels will accelerate the replacement of traditional panels, and the penetration rate will accelerate, with huge market potential. Summary of the invention

[0004] The disclosed embodiment provides a micro-LED substrate and a method for manufacturing the same. The micro-LED substrate can achieve seamless splicing between substrates and reduce the splicing seams at the splicing points. When the micro-LED is repaired, the yield rate can also be improved, and the growth of foreign matter on the substrate will not affect the light emission or display of the micro-LED.

[0005] At least one embodiment of the present disclosure provides a micro-LED substrate, comprising: a substrate, a driving circuit layer, located on a first side of the substrate; a plurality of micro-LEDs, located on a second side of the substrate, the second side and the first side being two opposite sides of the substrate; a plurality of connecting vias, penetrating the substrate; and a plurality of conductive structures, located within the plurality of connecting vias, and arranged one-to-one with the plurality of connecting vias, the plurality of connecting vias including a plurality of first connecting vias, the plurality of conductive structures including a plurality of first conductive structures, the plurality of first conductive structures being located within the plurality of first connecting vias, and the plurality of micro-LEDs being electrically connected to the driving circuit layer through the plurality of first conductive structures.

[0006] For example, in a micro-LED substrate provided in an embodiment of the present disclosure, each of the micro-LEDs includes a first pole and a second pole, one end of each of the first conductive structures is connected to the driving circuit layer, and the other end of each of the first conductive structures is exposed on the second side of the substrate to serve as a soldering pad, and the soldering pad is configured to be connected to the first pole or the second pole.

[0007] For example, in the micro-LED substrate provided in an embodiment of the present disclosure, at least one of the first connecting vias includes: a first sub-portion; and a second sub-portion, located on a side of the first sub-portion close to the driving circuit layer, and the average aperture of the second sub-portion is larger than the average aperture of the first sub-portion.

[0008] For example, in the micro-LED substrate provided by an embodiment of the present disclosure, in the direction from the substrate to the driving circuit layer, the aperture of the first sub-portion remains unchanged, and the aperture of the second sub-portion gradually decreases, and the maximum aperture of the second sub-portion is larger than the aperture of the first sub-portion.

[0009] For example, in a micro-LED substrate provided by an embodiment of the present disclosure, the cross section of the first sub-portion along a plane perpendicular to the substrate includes a rectangle, and the cross section of the second sub-portion along a plane perpendicular to the substrate includes a trapezoid.

[0010] For example, in a micro-LED substrate provided in an embodiment of the present disclosure, the substrate includes a base substrate and a first passivation layer, the first sub-portion is located on the base substrate, and the second sub-portion is located on the first passivation layer.

[0011] For example, in the micro-LED substrate provided by an embodiment of the present disclosure, at least one of the first conductive structures includes: a first conductive part, and a second conductive part, which is located on the side of the first conductive part close to the driving circuit layer, and the average radial dimension of the second conductive part is greater than the average radial dimension of the first conductive part.

[0012] For example, in the micro-LED substrate provided by an embodiment of the present disclosure, in the direction from the substrate to the driving circuit layer, the radial dimension of the first conductive part remains unchanged, and the radial dimension of the second conductive part gradually decreases, and the maximum radial dimension of the second conductive part is greater than the radial dimension of the first conductive part.

[0013] For example, in a micro-LED substrate provided by an embodiment of the present disclosure, the cross section of the first conductive portion along a plane perpendicular to the substrate includes a rectangle, and the cross section of the second conductive portion along a plane perpendicular to the substrate includes a trapezoid.

[0014] For example, in a micro-LED substrate provided in an embodiment of the present disclosure, the substrate includes a base substrate and a first passivation layer, the first conductive portion is located on the base substrate, and the second conductive portion is located on the first passivation layer.

[0015] For example, in the micro-LED substrate provided in an embodiment of the present disclosure, the driving circuit layer includes a plurality of signal lines and a plurality of connecting lines, and the micro-LED is connected to the signal lines through the first conductive structure and the connecting lines.

[0016] For example, a micro-LED substrate provided in an embodiment of the present disclosure further includes: a plurality of light-emitting units, each of which includes a plurality of micro-LEDs; and a plurality of first micro-driving chips, which are arranged corresponding to the plurality of light-emitting units, each of which is configured to drive the corresponding light-emitting unit to emit light, the plurality of connecting vias further include a plurality of second connecting vias, the plurality of conductive structures further include a plurality of second conductive structures, the plurality of second conductive structures are located in the plurality of second connecting vias, the plurality of first micro-driving chips are connected to the driving circuit layer through the plurality of second conductive structures, the plurality of signal lines include a driving voltage line, a ground line, a working voltage line and a source address line, the micro-LED is connected to the driving voltage line through the first conductive structure and the connecting line, the first micro-driving chip is respectively connected to the ground line, the working voltage line and the source address line through the second conductive structure and the connecting line, or the first micro-driving chip is respectively connected to the ground line, the working voltage line and the source address line through the second conductive structure, the first micro-driving chip includes an output end, and the micro-LED is connected to the output end through the first conductive structure and the connecting line.

[0017] For example, in the micro-LED substrate provided in an embodiment of the present disclosure, the driving circuit layer includes: a first conductive layer, a second passivation layer, located on the side of the first conductive layer away from the substrate; an insulating layer, located on the side of the second passivation layer away from the first conductive layer; a third passivation layer, located on the side of the insulating layer away from the second passivation layer; a second conductive layer, located on the side of the third passivation layer away from the insulating layer; and a plurality of first vias, penetrating the second passivation layer, the insulating layer and the third passivation layer, the first conductive layer includes a plurality of connecting lines, the second conductive layer includes a plurality of signal lines, the plurality of micro-LEDs are connected to the plurality of connecting lines of the first conductive layer through the plurality of first conductive structures, and the plurality of connecting lines of the first conductive layer are connected to the plurality of signal lines of the second conductive layer through the plurality of first vias.

[0018] For example, a micro-LED substrate provided in an embodiment of the present disclosure further includes: a plurality of light-emitting units, each of which includes a plurality of micro-LEDs; and a plurality of first micro-driving chips, which are arranged corresponding to the plurality of light-emitting units, each of which is configured to drive the corresponding light-emitting unit to emit light, the plurality of connecting vias further include a plurality of second connecting vias, the plurality of conductive structures further include a plurality of second conductive structures, the plurality of second conductive structures are located in the plurality of second connecting vias, the plurality of first micro-driving chips are connected to the driving circuit layer through the second conductive structures, the plurality of signal lines include a driving voltage line, a ground line, a working voltage line and a source address line, the micro-LED is connected to the driving voltage line through the connecting lines of the first conductive structure and the first conductive layer, the first micro-driving chip is respectively connected to the ground line, the working voltage line and the source address line through the connecting lines of the second conductive structure and the first conductive layer, the first micro-driving chip includes an output end, and the micro-LED is connected to the output end through the connecting lines.

[0019] For example, the micro-LED substrate provided in an embodiment of the present disclosure also includes multiple pixel units; and multiple second micro-driving chips, which are arranged corresponding to the multiple pixel units, and each of the second micro-driving chips is configured to drive the corresponding pixel unit for display, the multiple micro-LEDs include a first micro-LED, a second micro-LED and a third micro-LED, the first micro-LED is configured to emit light of a first color, the second micro-LED is configured to emit light of a second color, and the third micro-LED is configured to emit light of a third color, each of the pixel units includes the first micro-LED, the second micro-LED and the third micro-LED, the multiple connecting vias also include multiple second connecting vias, the multiple conductive structures also include multiple second conductive structures, the multiple second conductive structures are located in the multiple second connecting vias, and the multiple second micro-driving chips are connected to the driving circuit layer through the multiple second conductive structures.

[0020] For example, in the micro-LED substrate provided in an embodiment of the present disclosure, the multiple signal lines include a first signal line, a second signal line, a ground line, a working voltage line and a data line, the micro-LED is connected to the first signal line or the second signal line through the connecting line of the first conductive structure and the first conductive layer, the second micro-driving chip is respectively connected to the ground line, the working voltage line and the data line through the connecting line of the second conductive structure and the first conductive layer, and the second micro-driving chip includes three output terminals, and the three output terminals are respectively connected to the first micro-LED, the second micro-LED and the third micro-LED of the corresponding pixel unit.

[0021] For example, the micro-LED substrate provided in an embodiment of the present disclosure also includes: a fourth passivation layer, located on the first side of the substrate and on the side of the driving circuit layer away from the substrate; and a second via hole, penetrating the fourth passivation layer to expose the driving circuit layer.

[0022] At least one embodiment of the present disclosure further provides a display device, comprising any one of the above-mentioned micro-LED substrates.

[0023] At least one embodiment of the present disclosure also provides a method for manufacturing a micro-LED substrate, comprising: providing a substrate; forming a driving circuit layer on a first side of the substrate; forming a plurality of connecting vias penetrating the substrate on the substrate; forming a conductive structure in the connecting vias; and forming a plurality of micro-LEDs on a second side of the substrate, wherein the first side and the second side are opposite sides of the substrate, the plurality of connecting vias include a plurality of first connecting vias, the plurality of conductive structures include a plurality of first conductive structures, the plurality of first conductive structures are located in the plurality of first connecting vias, and the plurality of micro-LEDs are electrically connected to the driving circuit layer through the plurality of first conductive structures.

[0024] For example, in a manufacturing method provided in an embodiment of the present disclosure, providing a substrate includes: providing a base substrate; and forming a passivation layer on a side of the base substrate close to the driving circuit layer.

[0025] For example, in a manufacturing method provided in an embodiment of the present disclosure, forming a plurality of connecting vias on the substrate includes: forming a blind hole on the base substrate using a laser process; and etching the unpunched portion of the base substrate and the passivation layer along the extension direction of the blind hole using an etching process to form a first sub-portion passing through the base substrate and a second sub-portion passing through the passivation layer, wherein the first connecting via includes the first sub-portion and the second sub-portion.

[0026] For example, in a manufacturing method provided in an embodiment of the present disclosure, the average pore size of the second sub-portion is greater than the average pore size of the first sub-portion.

[0027] For example, in a manufacturing method provided in an embodiment of the present disclosure, in a direction from the substrate to the driving circuit layer, the aperture of the first sub-section remains unchanged, and the aperture of the second sub-section gradually decreases, and the maximum aperture of the second sub-section is larger than the aperture of the first sub-section.

[0028] For example, in a manufacturing method provided by an embodiment of the present disclosure, the cross-section of the first sub-portion along a plane perpendicular to the substrate includes a rectangle, and the cross-section of the second sub-portion along a plane perpendicular to the substrate includes a trapezoid.

[0029] For example, in the manufacturing method provided in an embodiment of the present disclosure, the thickness dimension of the non-perforated portion of the base substrate has a value range of 0.05-0.15 mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings in the following description only relate to some embodiments of the present disclosure, but are not intended to limit the present disclosure.

[0031] Figure 1 A schematic diagram of a foreign body growth causing blistering and corrosion of copper wire;

[0032] Figure 2 A schematic diagram of the splicing of a micro light-emitting diode product;

[0033] Figure 3A A cross-sectional schematic diagram of a micro-LED substrate provided by an embodiment of the present disclosure;

[0034] Figure 3B A cross-sectional schematic diagram of another micro-LED substrate provided by an embodiment of the present disclosure;

[0035] Figure 3C A schematic cross-sectional view of another micro-LED substrate provided by an embodiment of the present disclosure;

[0036] Figure 4 for Figure 3A A schematic diagram of a partial structure of a first connecting via shown;

[0037] Figure 5 for Figure 3A A partial structural schematic diagram of the first conductive structure shown;

[0038] Figure 6 A schematic diagram of drilling a hole in a substrate using a laser process provided in one embodiment of the present disclosure;

[0039] Figure 7 A schematic diagram of etching holes in a film layer using a dry etching process provided in one embodiment of the present disclosure;

[0040] Figure 8 A schematic diagram of wiring of a micro-LED substrate provided in one embodiment of the present disclosure;

[0041] Fig. 9 for Figure 8 A cross-sectional schematic diagram of a micro-LED substrate is shown;

[0042] Fig.10 A schematic diagram of wiring of another micro-LED substrate provided in an embodiment of the present disclosure;

[0043] Fig.11 for Fig.10 A cross-sectional schematic diagram of a micro-LED substrate is shown;

[0044] Fig.12 A schematic diagram of wiring of another micro-LED substrate provided in an embodiment of the present disclosure;

[0045] Fig.13 for Fig.12 A cross-sectional schematic diagram of a micro-LED substrate is shown;

[0046] Fig.14 A schematic diagram of a display device provided by an embodiment of the present disclosure;

[0047] Fig.15A A schematic diagram of a structure for drilling holes in a substrate using a laser;

[0048] Fig. 15B This is a structural diagram of a micro light-emitting diode product;

[0049] Fig.16 A flow chart of a method for manufacturing a micro-LED substrate provided in one embodiment of the present disclosure;

[0050] FIG. 17A to FIG. 17C A schematic diagram of a manufacturing method for forming a connecting via on a substrate according to an embodiment of the present disclosure;

[0051] 18A to 18H for Figure 8 A schematic diagram of a process for manufacturing a micro-LED substrate is shown; and

[0052] FIG. 19A to FIG. 19L for Fig.10 The schematic diagram of the manufacturing method of the micro-light-emitting diode substrate is shown. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0054] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. "First", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0055] Unless otherwise defined, the features such as "parallel", "perpendicular" and "same" used in the embodiments of the present disclosure include the situations of "parallel", "perpendicular", "same" in a strict sense, as well as the situations of "approximately parallel", "approximately perpendicular", "approximately the same", etc., which contain certain errors. For example, the above-mentioned "approximately" may mean that the difference of the compared objects is within 10% or 5% of the average value of the compared objects. When the number of a component or element is not specifically indicated in the following text of the embodiments of the present disclosure, it means that the component or element may be one or more, or may be understood as at least one. "At least one" refers to one or more, and "multiple" refers to at least two. The "same-layer arrangement" in the embodiments of the present disclosure refers to the relationship between multiple film layers formed by the same material after the same step (for example, a one-step patterning process). The "same layer" here does not always mean that the thickness of multiple film layers is the same or the height of multiple film layers in the cross-sectional view is the same.

[0056] Mini LED and Micro LED are used in backlight display products and have been gradually applied to TVs, gaming monitors and are gradually developing towards small sizes such as tablets. According to the different substrates, Mini LED and Micro LED products can be divided into glass substrates and printed circuit boards (PCBs). At present, the mainstream market, especially small-sized products, use PCB substrates. Glass substrates do not have problems such as poor heat dissipation, and glass substrates can also share lines with TFT products, which has greater prospects. Mini LED and Micro LED can be used in display products as an upgrade technology for LCD and OLED displays, and are gradually being used in display products.

[0057] When Mini LED and Micro LED products are tested for a long time, especially in the 8585O environment test, they are prone to poor reliability problems such as pad corrosion, weak light of lamp beads, and lamp failure, which affect product stability. There are two main reasons for the corrosion problem: one is that some Na and Ga components in the glass itself are separated and grown, causing the film layer to break, corrosion and related defects; the other is the growth of foreign matter caused by the introduction of particles during the coating process, which causes the film layer to break, corrosion and related defects. Both types of foreign matter growth will cause short circuit problems. Figure 1 Schematic diagram of a foreign body growth causing blistering and corrosion of copper wire. Figure 1 (b) Figure 1 (a) Cross-sectional view of the selected position along the extension direction of the copper wire, Figure 1 (c) Figure 1 (b) A local enlarged view of the selected position, such as Figure 1 As shown, the precipitates 11 of the bottom substrate 10 cause the copper wire 12 to bubble and corrode, resulting in problems such as line short circuit and pad corrosion.

[0058] During the product design process of Mini LED and Micro LED, the driving circuit layer and the micro light-emitting diode are located on the same side of the substrate, resulting in a binding area on the display side. At this time, due to the existence of the binding area, it is impossible to achieve seamless splicing of the substrate in all directions. Figure 2 This is a schematic diagram of the splicing of a micro-LED product. Figure 2 As shown, due to the presence of the binding area 14 on the display side 13 of the micro-LED product, seamless splicing in all directions cannot be achieved, and only left-right splicing can be performed.

[0059] The disclosed embodiment provides a micro-LED substrate and a method for manufacturing the same. The micro-LED substrate includes a substrate, a driving circuit layer, a plurality of micro-LEDs, a plurality of connecting vias, and a plurality of conductive structures. The driving circuit layer is located on a first side of the substrate, the plurality of micro-LEDs are located on a second side of the substrate, the second side and the first side are two opposite sides of the substrate, the plurality of connecting vias penetrate the substrate, the plurality of conductive structures are located within the plurality of connecting vias, and are arranged one-to-one with the plurality of connecting vias. The plurality of connecting vias include a plurality of first connecting vias, the plurality of conductive structures include a plurality of first conductive structures, the plurality of first conductive structures are located within the plurality of first connecting vias, and the plurality of micro-LEDs are electrically connected to the driving circuit layer through the plurality of first conductive structures.

[0060] In the micro-LED substrate provided in the embodiment of the present disclosure, the driving circuit layer and the micro-LED are located on both sides of the substrate, the side where the micro-LED is located is the display side, and the side where the driving circuit layer is located is the non-display side, so that the binding area is also located on the non-display side, thereby achieving seamless splicing between the substrates, reducing the splicing seams at the splicing points, and improving the display effect after splicing. Compared with the conventional solid crystal structure, the micro-LED is fixed on the substrate through the first conductive structure in the first connecting via. When the micro-LED is repaired, the first conductive structure will be thinned less copper, and the yield rate will be improved when the second solid crystal process is performed. In addition, during the repair process, the first connecting via has a leveling effect, and more copper will be concentrated in the first connecting via, so that the first conductive structure will be thinned less copper during the repair process, further improving the yield rate. The micro-LED on the display side is directly assembled to the display side of the substrate, and the driving circuit layer is located on the non-display side, so that the growth of foreign matter on the substrate will not affect the light emission or display of the micro-LED, and the corrosion resistance and other properties of the product can be improved. The micro-LED and the driving circuit layer are located on both sides of the substrate, and the overall voltage and current will become smaller, thereby improving the corrosion problem of the circuit. In addition, by arranging the micro-LED and the driving circuit layer on both sides of the substrate, the layout space of the micro-LED can be larger and the density of the micro-LED can be increased. It should be noted that the "micro-LED" in this article is not encapsulated, and only includes the PN junction, the light-emitting layer and other functional layers that assist in light emission, and is not a common single light-emitting diode.

[0061] The micro-LED substrate and the manufacturing method thereof provided by the embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0062] An embodiment of the present disclosure provides a micro light emitting diode substrate. Figure 3A The cross-sectional diagram of a micro-LED substrate provided by an embodiment of the present disclosure is shown in FIG. Figure 3A As shown, the micro-LED substrate 200 includes a substrate 100, a driving circuit layer 110, a plurality of micro-LEDs 120, a plurality of connecting vias 130, and a plurality of conductive structures 140. The driving circuit layer 110 is located on the first side S1 of the substrate 100, the plurality of micro-LEDs 120 are located on the second side S2 of the substrate 100, the second side S2 and the first side S1 are two opposite sides of the substrate 100, the plurality of connecting vias 130 penetrates the substrate 100, the plurality of conductive structures 140 are located within the plurality of connecting vias 130, and are arranged one-to-one with the plurality of connecting vias 130. The plurality of connecting vias 130 include a plurality of first connecting vias 131, the plurality of conductive structures 140 include a plurality of first conductive structures 141, the plurality of first conductive structures 141 are located within the plurality of first connecting vias 131, and the plurality of micro-LEDs 120 are electrically connected to the driving circuit layer 110 through the plurality of first conductive structures 141.

[0063] In the micro-LED substrate provided in the embodiment of the present disclosure, the driving circuit layer 110 and the micro-LED 120 are located on both sides of the substrate 100, the side where the micro-LED 120 is located is the display side, and the side where the driving circuit layer 110 is located is the non-display side, so that the binding area is also located on the non-display side, thereby achieving seamless splicing between the substrates 100, reducing the splicing seams at the splicing points, and improving the display effect after splicing. Compared with the conventional design in which the micro-LED 120 is fixed by the pads on the copper wire, the micro-LED 120 is fixed on the substrate 100 by the first conductive structure 141 in the first connecting via 131. When the micro-LED 120 is repaired, the first conductive structure 141 will reduce the copper thinning, and the yield rate will be improved when the second solid crystal process is performed. In addition, during the repair process, the first connecting via 131 has a leveling effect, and more copper will be concentrated in the first connecting via 131, so that the first conductive structure 141 will reduce the copper thinning during the repair process, further improving the yield rate. The micro-LED 120 on the display side is directly assembled to the display side of the substrate 100, and the driving circuit layer 110 is located on the non-display side, so that the growth of foreign matter on the substrate will not affect the light emission or display of the micro-LED 120, and the corrosion resistance and other performance of the product can be improved. The micro-LED 120 and the driving circuit layer 110 are located on both sides of the substrate 100, and the overall voltage and current will become smaller, which will also improve the corrosion problem of the circuit. In addition, by arranging the micro-LED 120 and the driving circuit layer 110 on both sides of the substrate 100, the layout space of the micro-LED 120 can be larger, and the density of the micro-LED 120 can be increased.

[0064] For example, the “micro light emitting diode 120” in this article may not be packaged, and may only include a PN junction, a light emitting layer, and other functional layers that assist in emitting light. Of course, the embodiments of the present disclosure are not limited to this.

[0065] In some examples, such as Figure 3A As shown, each micro LED 120 includes a first electrode 121 and a second electrode 122, and the first electrode 121 and the second electrode 122 are respectively connected to the driving circuit layer 110 through different first conductive structures 141. For example, each micro LED 120 also includes a light-emitting functional layer 123.

[0066] Figure 3B This is a cross-sectional schematic diagram of another micro-LED substrate provided by an embodiment of the present disclosure. Figure 3BAs shown, each micro-LED 120 includes a first electrode 121 and a second electrode 122, one end of each first conductive structure 141 is connected to the driving circuit layer 110, and the other end of each first conductive structure 141 is exposed at the second side S2 of the substrate 100 to serve as a pad, and the pad is configured to be connected to the first electrode or the second electrode of the micro-LED 120. Thus, the micro-LED 120 can be connected to the first conductive structure 141 more conveniently and more effectively, thereby improving the die bonding efficiency and die bonding yield of the micro-LED 120.

[0067] Figure 3C FIG. 1 is a cross-sectional view of another micro-LED substrate provided by an embodiment of the present disclosure. Figure 3C As shown, the section line only cuts through the first pole 121 or the second pole 122 of the micro light emitting diode 120 , and the micro light emitting diode 120 only shows that one of the first pole 121 or the second pole 122 is connected to the first conductive structure 141 .

[0068] In some examples, such as FIG. 3A to FIG. 3C As shown, at least one first connection via 131 includes a first sub-portion 132 and a second sub-portion 133. The second sub-portion 133 is located on the side of the first sub-portion 132 close to the driving circuit layer 110, and the average pore size of the second sub-portion 133 is larger than the average pore size of the first sub-portion 132, so that the contact adhesion between the first conductive structure 141 in the first connection via 131 and the driving circuit layer 110 can be improved, and the performance stability can be improved. At this time, the overall cross-sectional shape of the first connection via 131 can be approximately anchor-shaped, and the overall cross-sectional shape of the first conductive structure 141 located in the first connection via 131 can be approximately anchor-shaped. The anchor-shaped design of the first connection via 131 and the first conductive structure 141 can improve the contact adhesion between the first conductive structure 141 in the first connection via 131 and the driving circuit layer 110, and improve the performance stability.

[0069] In some examples, such as FIG. 3A to FIG. 3C As shown, in the direction from the substrate 100 to the driving circuit layer 110, the aperture of the first sub-portion 132 is substantially constant, and the aperture of the second sub-portion 133 gradually decreases, and the maximum aperture of the second sub-portion 133 is larger than the aperture of the first sub-portion 132. Therefore, the shape of the first connecting via 131 can be approximately anchor-shaped, and the first conductive structure 141 located in the first connecting via 131 can be approximately anchor-shaped. The anchor-shaped design of the first connecting via 131 and the first conductive structure 141 can enhance the contact adhesion between the first conductive structure 141 in the first connecting via 131 and the driving circuit layer 110, thereby improving the performance stability.

[0070] In some examples, such as FIG. 3A to FIG. 3CAs shown, the cross section of the first sub-portion 132 along the plane perpendicular to the substrate 100 includes a rectangle, and the cross section of the second sub-portion 133 along the plane perpendicular to the substrate 100 includes a trapezoid, and the bottom side of the trapezoid is connected to the rectangle.

[0071] In some examples, such as FIG. 3A to FIG. 3C As shown, the substrate 100 includes a base substrate 101 and a first passivation layer 102, a first sub-portion 132 is located on the base substrate 101, and a second sub-portion 133 is located on the first passivation layer 102. The first sub-portion 132 is a via formed on the base substrate 101, and the second sub-portion 133 is a via formed on the first passivation layer 102.

[0072] Figure 4 for Figure 3A The partial structural diagram of the first connecting via is shown in FIG. Figure 3A and Figure 4 As shown, the aperture of the first sub-section 132 is D1, the maximum aperture of the second sub-section 133 is D2, the minimum aperture of the second sub-section 133 is D3, the thickness of the first passivation layer 102 is H, and the angle between the side of the second sub-section 133 and the bottom surface of the substrate 101 is θ1. For example, the relationship between D1 and D3 can satisfy: D3 ≥ D1. For example, the relationship between D1, D2 and D3 can satisfy: D2 ≥ D3 + 2H / tanθ1. Of course, Figure 3B and Figure 3C The first connecting via also satisfies the above relationship, which will not be described in detail here.

[0073] In some examples, such as FIG. 3A to FIG. 3C As shown, at least one first conductive structure 141 includes a first conductive portion 142 and a second conductive portion 143, and the second conductive portion 143 is located on a side of the first conductive portion 142 close to the driving circuit layer 110. The average radial dimension of the second conductive portion 143 is greater than the average radial dimension of the first conductive portion 142. Thus, the shape of the first conductive structure 141 can be approximately anchor-shaped, thereby improving the contact adhesion between the first conductive structure 141 and the driving circuit layer 110 and improving performance stability.

[0074] In some examples, such as FIG. 3A to FIG. 3C As shown, in the direction from the substrate 100 to the driving circuit layer 110, the radial dimension of the first conductive portion 142 is substantially constant, and the radial dimension of the second conductive portion 143 gradually decreases, and the maximum radial dimension of the second conductive portion 143 is greater than the radial dimension of the first conductive portion 142. Thus, the shape of the first conductive structure 141 can be approximately anchor-shaped, thereby improving the contact adhesion between the first conductive structure 141 and the driving circuit layer 110 and improving performance stability.

[0075] In some examples, such as FIG. 3A to FIG. 3CAs shown, the cross section of the first conductive portion 142 along the plane perpendicular to the substrate 100 includes a rectangle, and the cross section of the second conductive portion 143 along the plane perpendicular to the substrate 100 includes a trapezoid.

[0076] In some examples, such as FIG. 3A to FIG. 3C As shown, the substrate 100 includes a base substrate 101 and a first passivation layer 102. The first conductive portion 142 is located in a via hole of the base substrate 101, for example, the via hole is the first sub-portion 132. The second conductive portion 143 is located in a via hole of the first passivation layer 102, for example, the via hole is the second sub-portion 133.

[0077] Figure 5 for Figure 3A The partial structural diagram of the first conductive structure is shown in FIG. Figure 3A and Figure 5 As shown, the radial dimension of the first conductive portion 142 is D10, the maximum radial dimension of the second conductive portion 143 is D20, the minimum radial dimension of the second conductive portion 143 is D30, the thickness of the first passivation layer 102 is H, and the angle between the side of the second conductive portion 143 and the bottom surface of the base substrate 101 is θ2. For example, the relationship between D10 and D30 can satisfy: D30 ≥ D10. For example, the relationship between D10, D20 and D30 can satisfy: D20 ≥ D30 + 2H / tanθ2. Of course, Figure 3B and Figure 3C The first conductive structure also satisfies the above relationship, which will not be described in detail here.

[0078] In some examples, such as Figure 4 and Figure 5 As shown, the aperture D1 of the first sub-portion 132 is equal to the radial dimension D10 of the first conductive portion 142, the maximum aperture D2 of the second sub-portion 133 is equal to the maximum radial dimension D20 of the second conductive portion 143, the minimum aperture D3 of the second sub-portion 133 is equal to the minimum radial dimension D30 of the second conductive portion 143, and the angle θ1 between the side of the second sub-portion 133 and the bottom surface of the base substrate 101 is equal to the angle θ2 between the side of the second conductive portion 143 and the bottom surface of the base substrate 101.

[0079] Figure 6 A schematic diagram of drilling a hole in a substrate using a laser process is provided in accordance with an embodiment of the present disclosure. Figure 6 As shown, from left to right, it can be seen that when the laser process is used to punch a hole in the substrate 20, as the depth of the hole 21 increases, the profile of the hole 21 does not change substantially, and the side of the hole 21 is approximately perpendicular to the surface of the substrate 20. Thus, the first sub-portion 132 of the first connecting via 131 can be formed on the substrate by the laser process. Of course, the embodiment of the present disclosure does not limit the formation process of the first sub-portion 132.

[0080] Figure 7 A schematic diagram of etching holes in a film layer using a dry etching process is provided in accordance with an embodiment of the present disclosure. Figure 7 As shown in (a), when the film layer 22 is etched by dry etching process, the dry etching parameters can be adjusted so that the angle θ between the profile of the hole 23 and the bottom surface of the film layer 22 is approximately 30 degrees, as shown in FIG. Figure 7 As shown in (b), the angle θ between the profile of the hole 23 and the bottom surface of the film layer 22 is approximately 80 degrees, so that the value of the angle θ between the profile of the hole 23 and the bottom surface of the film layer 22 can be adjusted between 30 degrees and 80 degrees, which corresponds to the angle θ1 in the aforementioned embodiment, so that the second sub-portion 133 of the first connecting via 131 can be formed by a dry etching process, and holes with different profiles can be etched according to design requirements. Of course, the embodiment of the present disclosure does not limit the formation process of the first sub-portion 132.

[0081] For example, FIG. 3A to FIG. 3C , Figure 6 and Figure 7 As shown, a blind hole can be first formed on the base substrate 101 using a laser process, and then the unetched portion of the base substrate 101 and the first passivation layer 102 can be etched using an etching process, thereby forming a first sub-portion 132 on the base substrate 101 and a second sub-portion 133 on the first passivation layer 102.

[0082] In some examples, such as FIG. 3A to FIG. 3CAs shown, the micro-LED substrate also includes a plurality of micro-driving chips 150, each of which is configured to drive the corresponding micro-LED 120 to emit light or display. The plurality of connecting vias 130 also includes a plurality of second connecting vias 134, the plurality of conductive structures 140 also includes a plurality of second conductive structures 144, the plurality of second conductive structures 144 are located in the plurality of second connecting vias 134, and the plurality of micro-driving chips 150 are connected to the driving circuit layer 110 through the plurality of second conductive structures 144. The micro-driving chip 150 on the display side is directly assembled to the display side of the substrate 100, and the driving circuit layer 110 is located on the non-display side, so that the growth of foreign matter will not affect the micro-driving chip 150, and the corrosion resistance and other performance of the product can be improved. At the same time, the micro-driving chip 150 and the micro-LED 120 are arranged on the same side of the substrate 100, which also facilitates the assembly of the micro-driving chip 150 and the micro-LED 120. It should be noted that the second connecting via 134 may also include a first sub-portion 132 and a second sub-portion 133, and the second conductive structure 144 may also include a first conductive portion 142 and a second conductive portion 143. The design of the size and other parameters of the second connecting via 134 is the same as that of the first connecting via 131, and the design of the size and other parameters of the second conductive structure 144 is the same as that of the first conductive structure 141, so that the second conductive structure 144 can have the same beneficial effects as the first conductive structure 141, which will not be repeated here. It should be noted that FIG. 3A to FIG. 3C The micro-driving chip 150 is only schematically shown to be connected to the second conductive structure 144. For example, the micro-driving chip 150 may include multiple terminals, for example, the multiple terminals include multiple input terminals and multiple output terminals. The multiple terminals of the micro-driving chip 150 are connected to the second conductive structure 144 to achieve connection with the driving circuit layer 110.

[0083] In some examples, such as FIG. 3A to FIG. 3C As shown, the micro-LED substrate further includes a passivation layer 119 and a via V1. The passivation layer 119 is located on the first side S1 of the substrate 100 and on the side of the driving circuit layer 110 away from the substrate 100. The via V1 penetrates the passivation layer 119 to expose the driving circuit layer 110. Thus, the driving circuit board and the flexible circuit board can be arranged on the first side S1 of the substrate 100, that is, the non-display side. One end of the flexible circuit board can be connected to the driving circuit layer 110 through the via V1, and the other end of the flexible circuit board is connected to the driving circuit board, thereby realizing seamless splicing between the substrates 100, reducing the splicing seam at the splicing point, and improving the display effect after splicing.

[0084] In some examples, the substrate 100 includes but is not limited to a glass substrate, a printed circuit board, a resin substrate, etc. For example, the base substrate 101 includes but is not limited to a glass substrate, etc.

[0085] Figure 8A schematic diagram of wiring of a micro-LED substrate provided in one embodiment of the present disclosure; Fig. 9 for Figure 8 The cross-sectional schematic diagram of the micro-LED substrate is shown in FIG. Figure 8 and Fig. 9 As shown, the driving circuit layer 110 of the micro-LED substrate includes a plurality of signal lines 200 and a plurality of connecting lines 210, and the micro-LED 120 is connected to the signal lines 200 through the first conductive structure 141 and the connecting lines 210. Thus, the signal lines 200 can provide signals to the micro-LED 120 to realize the light emission of the micro-LED 120. For example, the micro-LED substrate can be used in a backlight module of a display device.

[0086] In some examples, such as Figure 8 and Fig. 9 As shown, the micro-LED substrate further includes a plurality of light-emitting units and a plurality of first micro-driving chips 151, each light-emitting unit includes a plurality of micro-LEDs 120; a plurality of first micro-driving chips 151 are arranged corresponding to the plurality of light-emitting units, and each first micro-driving chip 151 is configured to drive the corresponding light-emitting unit to emit light. Thus, the corresponding light-emitting unit can be driven to emit light by the micro-driving chip.

[0087] In some examples, such as Figure 8 and Fig. 9 As shown, the multiple connection vias 130 also include multiple second connection vias 134 , the multiple conductive structures 140 also include multiple second conductive structures 144 , the multiple second conductive structures 144 are located in the multiple second connection vias 134 , and the multiple first micro-drive chips 151 are connected to the drive circuit layer 110 through the multiple second conductive structures 144 .

[0088] In some examples, such as Figure 8 As shown, the plurality of signal lines 200 include a driving voltage line Vled, a ground line GND, an operating voltage line VCC, a source address line ADDR, etc. For example, the plurality of signal lines 200 may extend along the second direction Y direction.

[0089] In some examples, such as Figure 8 As shown, the plurality of connection lines 210 may extend along a first direction X, or may extend along a second direction Y.

[0090] In some examples, such as Figure 8As shown, each light-emitting unit includes four micro-LEDs 120, and the four micro-LEDs 120 are connected in series through a connection line 210 extending along the first direction X and two connection lines 210 extending along the second direction Y of the first conductive layer 112. Of course, the embodiment of the present disclosure does not limit the number of micro-LEDs 120 included in the light-emitting unit, and does not limit the series or parallel connection mode of the multiple micro-LEDs 120 included in each light-emitting unit.

[0091] In some examples, such as Figure 8 As shown, the micro light emitting diode 120 in the light emitting unit is connected to the driving voltage line Vled through the first conductive structure 141 and the connecting line 210 .

[0092] In some examples, such as Fig. 9 As shown, the micro LED 120 includes a first electrode 121 and a second electrode 122, which are respectively connected to the first conductive structure 141. For example, one end of the first conductive structure 141 is exposed at the second side S2 of the substrate 100 to serve as a pad, and of course, the embodiment of the present disclosure is not limited to this.

[0093] In some examples, such as Figure 8 As shown, the first micro-driving chip 151 is respectively connected to the working voltage line VCC and the source address line ADDR through the second conductive structure 144, and the first micro-driving chip 151 is connected to the ground line GND through the second conductive structure 144 and the connecting line 210. Of course, the embodiment of the present disclosure does not limit the connection method of the first micro-driving chip 151 with the ground line GND, the working voltage line VCC and the source address line ADDR, and they can be directly connected through the second conductive structure 144, or they can be connected through the second conductive structure 144 and the connecting line 210.

[0094] In some examples, such as Figure 8 As shown, the first micro-driving chip 151 also includes an output end, and the micro light emitting diode 120 is connected to the output end through the first conductive structure 141 and the connecting wire 210 .

[0095] In some examples, such as Figure 8 As shown, the plurality of micro LEDs 120 in the light emitting unit are arranged between the driving voltage line Vled and the ground line GND. For example, the first micro driving chip 151 is arranged between the driving voltage line Vled and the ground line GND. For example, in a direction perpendicular to the driving voltage line Vled, the plurality of micro LEDs 120 of the light emitting unit are arranged between the driving voltage line Vled and the first micro driving chip 151.

[0096] In some examples, such as Fig. 9As shown, the micro-LED substrate further includes a passivation layer 119 and a via hole V1. The passivation layer 119 is located on the first side S1 of the substrate 100, and is located on the side of the driving circuit layer 110 away from the substrate 100. Thus, the driving circuit board and the flexible circuit board can be arranged on the first side S1 of the substrate 100, that is, the non-display side, and one end of the flexible circuit board can be connected to the driving circuit layer 110 through the via hole V1, and the other end of the flexible circuit board is connected to the driving circuit board, thereby realizing seamless splicing between the substrates 100, reducing the splicing seam at the splicing point, and improving the display effect after splicing.

[0097] Fig.10 A schematic diagram of wiring of another micro-LED substrate provided in an embodiment of the present disclosure; Fig.11 for Fig.10 The cross-sectional schematic diagram of the micro-LED substrate is shown in FIG. Fig.10 and Fig.11 As shown, the driving circuit layer 110 of the micro-LED substrate includes a first conductive layer 112, a second passivation layer 113, an insulating layer 114, a third passivation layer 115, a second conductive layer 116, and a plurality of via holes V2. The second passivation layer 113 is located on the side of the first conductive layer 112 away from the substrate 100, the insulating layer 114 is located on the side of the second passivation layer 113 away from the first conductive layer 112, the third passivation layer 115 is located on the side of the insulating layer 114 away from the second passivation layer 113, and the second conductive layer 116 is located on the side of the third passivation layer 115 away from the insulating layer 114; and a plurality of via holes V2 penetrate the second passivation layer 113, the insulating layer 114, and the third passivation layer 115. The first conductive layer 112 includes a plurality of connection lines 210, the second conductive layer 116 includes a plurality of signal lines 200, and the plurality of micro-LEDs 120 are connected to the plurality of connection lines 210 of the first conductive layer 112 through a plurality of first conductive structures 141, and the first conductive layer 112 is connected to the plurality of signal lines 200 of the second conductive layer 116 through a plurality of vias V2. For example, the micro-LED substrate can be used for products with more complex circuits and a higher density of micro-LEDs 120. For example, the micro-LED substrate can be used in a backlight module of a display device. It should be noted that Fig.10 Only the first electrode 121 and the second electrode 122 of the micro light emitting diode 120 are shown.

[0098] In some examples, such as Fig.10 and Fig.11 As shown, the micro-LED substrate further includes a plurality of light-emitting units and a plurality of first micro-driving chips 151, each light-emitting unit includes a plurality of micro-LEDs 120; the plurality of first micro-driving chips 151 are arranged corresponding to the plurality of light-emitting units, and each micro-driving chip is configured to drive the corresponding light-emitting unit to emit light. It should be noted that Fig.10 Only the terminals of the first micro driving chip 151 are shown.

[0099] In some examples, such as Fig.11 As shown, the multiple connection vias 130 also include multiple second connection vias 134 , the multiple conductive structures 140 also include multiple second conductive structures 144 , the multiple second conductive structures 144 are located in the multiple second connection vias 134 , and the multiple first micro-drive chips 151 are connected to the drive circuit layer 110 through the multiple second conductive structures 144 .

[0100] In some examples, such as Fig.10 As shown, the plurality of signal lines 200 include a driving voltage line Vled, a ground line GND, an operating voltage line VCC and a source address line ADDR. For example, the plurality of signal lines 200 may extend along the second direction Y direction.

[0101] In some examples, such as Fig.10 As shown, the plurality of connection lines 210 may extend along a first direction X, or may extend along a second direction Y.

[0102] In some examples, such as Fig.10 As shown, each light-emitting unit includes six micro-LEDs 120, and the six micro-LEDs 120 are connected in series through a plurality of connecting wires 112 extending along the first direction X of the first conductive layer 112 and a plurality of connecting wires 112 extending along the second direction Y. Of course, the embodiment of the present disclosure does not limit the number of micro-LEDs 120 included in the light-emitting unit, and does not limit the series or parallel connection mode of the plurality of micro-LEDs 120 included in each light-emitting unit.

[0103] In some examples, such as Fig.10 and Fig.11 As shown, the micro light emitting diode 120 in the light emitting unit is connected to the driving voltage line Vled of the second conductive layer 116 through the first conductive structure 141 and the connecting line 112 of the first conductive layer 112 .

[0104] In some examples, such as Fig.10 and Fig.11 As shown, the first micro-driving chip 151 is respectively connected to the ground line GND, the working voltage line VCC and the source address line ADDR through the second conductive structure 144 and the connecting line 112 of the first conductive layer 112 .

[0105] In some examples, such as Fig.10 and Fig.11 As shown, the first micro-driving chip 151 further includes at least one output terminal 153 , and the micro light emitting diode 120 is connected to the output terminal through the first conductive structure 141 and the connecting wire 112 of the first conductive layer 112 .

[0106] In some examples, such as Fig.10 As shown, the first micro-driving chip 151 corresponds to four groups of light-emitting units and controls the four groups of light-emitting units to emit light.

[0107] In some examples, such as Fig.10 As shown, the micro-LED substrate further includes a passivation layer 119 and a via hole V1. The passivation layer 119 is located on the first side S1 of the substrate 100 and on the side of the driving circuit layer 110 away from the substrate 100. Thus, the driving circuit board and the flexible circuit board can be arranged on the first side S1 of the substrate 100, that is, the non-display side, and one end of the flexible circuit board can be connected to the second conductive layer 116 through the via hole V1, and the other end of the flexible circuit board is connected to the driving circuit board, thereby realizing seamless splicing between the substrates 100, reducing the splicing seam at the splicing point, and improving the display effect after splicing.

[0108] Fig.12 A schematic diagram of wiring of another micro-LED substrate provided in an embodiment of the present disclosure; Fig.13 for Fig.12 The cross-sectional schematic diagram of the micro-LED substrate is shown in FIG. Fig.12 and Fig.13 As shown, the driving circuit layer 110 of the micro-LED substrate includes a first conductive layer 112, a second passivation layer 113, an insulating layer 114, a third passivation layer 115, a second conductive layer 116, and a plurality of via holes V2. The second passivation layer 113 is located on the side of the first conductive layer 112 away from the substrate 100, the insulating layer 114 is located on the side of the second passivation layer 113 away from the first conductive layer 112, the third passivation layer 115 is located on the side of the insulating layer 114 away from the second passivation layer 113, and the second conductive layer 116 is located on the side of the third passivation layer 115 away from the insulating layer 114; and a plurality of via holes V2 penetrate the second passivation layer 113, the insulating layer 114, and the third passivation layer 115. The first conductive layer 112 includes a plurality of connection lines 210, the second conductive layer 116 includes a plurality of signal lines 200, the plurality of micro-LEDs 120 are connected to the plurality of connection lines 210 of the first conductive layer 112 through a plurality of first conductive structures 141, and the first conductive layer 112 is connected to the plurality of signal lines 200 of the second conductive layer 116 through a plurality of vias V2. For example, the micro-LED substrate can be used for direct display products.

[0109] In some examples, such as Fig.12 and Fig.13 As shown, the micro LED substrate further includes a plurality of pixel units and a plurality of second micro driving chips 152. The plurality of second micro driving chips 152 are arranged corresponding to the plurality of pixel units, and each second micro driving chip 152 is configured to drive the corresponding pixel unit for display.

[0110] In some examples, such as Fig.12 and Fig.13 As shown, the plurality of micro-LEDs 120 include a first micro-LED, a second micro-LED and a third micro-LED, the first micro-LED is configured to emit light of a first color, the second micro-LED is configured to emit light of a second color, and the third micro-LED is configured to emit light of a third color, and each pixel unit includes the first micro-LED, the second micro-LED and the third micro-LED. It should be noted that the first color, the second color and the third color are different. For example, the first color is green, the second color is red, and the third color is blue. Of course, the present disclosure includes but is not limited to this, and the above-mentioned first color, second color and third color may also be other colors.

[0111] In some examples, such as Fig.12 and Fig.13 As shown, the multiple connection vias 130 also include multiple second connection vias 134 , the multiple conductive structures 140 also include multiple second conductive structures 144 , the multiple second conductive structures 144 are located in the multiple second connection vias 134 , and the multiple second micro-driving chips 152 are connected to the driving circuit layer 110 through the multiple second conductive structures 144 .

[0112] In some examples, such as Fig.12 As shown, the plurality of signal lines 200 include a first signal line VR, a second signal line VGB, a ground line GND, an operating voltage line VCC and a data line DATA. For example, the plurality of signal lines 200 may extend along the second direction Y direction.

[0113] In some examples, such as Fig.12 As shown, the plurality of connection lines 210 may extend along a first direction X, may extend along a second direction Y, or may extend along a direction forming a certain angle with the first direction X.

[0114] In some examples, such as Fig.12 and Fig.13 As shown, the micro LED 120 is connected to the first signal line VR or the second signal line VGB through the first conductive structure 141 and the connecting line 210 of the first conductive layer 112 .

[0115] In some examples, such as Fig.12 and Fig.13 As shown, the second micro-driving chip 152 is respectively connected to the ground line GND, the working voltage line VCC and the data line DATA through the second conductive structure 144 and the connecting line 210 of the first conductive layer 112, and the second micro-driving chip 152 also includes three output terminals, which are respectively connected to the first micro-light emitting diode, the second micro-light emitting diode and the third micro-light emitting diode of the corresponding pixel unit.

[0116] In some examples, such as Fig.12 As shown, the first conductive layer 112 may further include a plurality of connection blocks 211. For example, the plurality of connection blocks 211 are located at both ends of the plurality of connection lines 210 to be connected to the plurality of signal lines 200 or the plurality of conductive structures 140. For example, the plurality of connection blocks 211 are arranged in a one-to-one correspondence with the plurality of signal lines 200 and are connected through the vias V2. For example, the plurality of connection blocks 211 are arranged in a one-to-one correspondence with the plurality of conductive structures 140. For example, the orthographic projection of the via V2 on the substrate 100 is within the orthographic projection of the corresponding connection block 211 on the substrate 100. For example, the orthographic projection of the conductive structure 140 on the substrate 100 is within the orthographic projection of the corresponding connection block 211 on the substrate 100.

[0117] In some examples, such as Fig.13 As shown, the micro-LED substrate further includes a passivation layer 119 and a via hole V1. The passivation layer 119 is located on the first side S1 of the substrate 100, and is located on the side of the driving circuit layer 110 away from the substrate 100. Thus, the driving circuit board and the flexible circuit board can be arranged on the first side S1 of the substrate 100, that is, the non-display side, and one end of the flexible circuit board can be connected to the driving circuit layer 110 through the via hole V1, and the other end of the flexible circuit board is connected to the driving circuit board, thereby realizing seamless splicing between the substrates 100, reducing the splicing seam at the splicing point, and improving the display effect after splicing.

[0118] An embodiment of the present disclosure further provides a display device. Fig.14 Schematic diagram of a display device provided by an embodiment of the present disclosure. Fig.14 As shown, the display device 300 includes any of the above-mentioned micro-LED substrates 200. Therefore, the display device 300 has the beneficial effects corresponding to the beneficial effects of the micro-LED substrate 200, which will not be repeated here.

[0119] For example, the display device may be a television, a computer, a navigation system, a car computer, an electronic picture frame, a tablet computer, a mobile phone, or other electronic product with a display function.

[0120] On the other hand, when Mini LED and Micro LED are used in direct display products, the driving circuit layer and the micro light-emitting diode are located on the same side of the glass substrate. The signal line of the driving circuit layer can be introduced into the back side of the glass substrate through the vias formed by laser on the glass substrate. The binding area and the driving circuit layer and the light-emitting device layer are respectively located on both sides of the glass substrate. Although such a design can achieve seamless splicing in all directions, it has extremely high process requirements and a high process defect rate. It is prone to problems such as film shedding, etching residues, and damage to the organic film layer, and its mass production is poor. Fig.15A A schematic diagram of a structure for drilling holes in a substrate using a laser; Fig. 15B This is a structural diagram of a micro-LED product. Fig.15AAs shown, when a laser is used to punch a hole in the substrate 15, if there is no film layer on the back side of the substrate 15, the laser can completely penetrate the substrate to form a via hole 16. However, if there is a film layer 17 on the back side of the substrate 15, it is impossible to directly use the laser to form the via hole 16 while ensuring that the film layer 17 on the back side is not damaged. Fig. 15B As shown, since this product has a film layer on the back side of the substrate, the laser drilling process causes film damage, film bubbling and separation on the back side of the substrate, resulting in poor mass productivity. The framed positions in the figure are the locations where the film layer is damaged and the film layer is bubbled and separated.

[0121] In this regard, an embodiment of the present disclosure further provides a method for manufacturing a micro-LED substrate. Fig.16 The present invention provides a flowchart of a method for manufacturing a micro-LED substrate according to an embodiment of the present invention. Fig.16 As shown, the method for manufacturing the micro-LED substrate includes the following steps:

[0122] S110: providing a substrate;

[0123] S120: forming a driving circuit layer on the first side of the substrate;

[0124] S130: forming a plurality of connection vias penetrating the substrate on the substrate;

[0125] S140: forming a conductive structure in the connecting via hole;

[0126] S150: A plurality of micro-LEDs are formed on the second side of the substrate, the first side and the second side are two opposite sides of the substrate, the plurality of connecting vias include a plurality of first connecting vias, the plurality of conductive structures include a plurality of first conductive structures, the plurality of first conductive structures are located in the plurality of first connecting vias, and the plurality of micro-LEDs are electrically connected to the driving circuit layer through the plurality of first conductive structures.

[0127] In the manufacturing method of the micro-LED substrate provided by the embodiment of the present disclosure, a driving circuit layer is formed on the first side of the substrate, and a micro-LED is formed on the second side of the substrate. The driving circuit layer and the micro-LED are located on both sides of the substrate. The first side where the micro-LED is located is the display side, and the second side where the driving circuit layer is located is the non-display side, so that the binding area is also located on the non-display side, thereby achieving seamless splicing between the substrates, reducing the splicing seam at the splicing point, and improving the display effect after splicing. Compared with the conventional design in which the micro-LED is fixed by the pad on the copper wire, the micro-LED is fixed on the substrate by the first conductive structure in the first connecting via. When the micro-LED is repaired, the first conductive structure will be thinned less copper, and the yield rate will be improved when the second solid crystal process is performed. In addition, during the repair process, the first connecting via has a leveling effect, and more copper will be concentrated in the first connecting via, so that the first conductive structure will be thinned less copper during the repair process, further improving the yield rate. The micro-LEDs on the display side are directly assembled to the display side of the substrate, and the driving circuit layer is located on the non-display side, so that foreign matter growth will not affect the light emission or display of the micro-LEDs, and the corrosion resistance and other performance of the product can be improved. The micro-LEDs and the driving circuit layer are located on both sides of the substrate, and the overall voltage and current will become smaller, which will also improve the corrosion problem of the circuit. In addition, arranging the micro-LEDs and the driving circuit layer on both sides of the substrate can make the layout space of the micro-LEDs larger and increase the density of the micro-LEDs.

[0128] In some examples, in the method for manufacturing the micro-LED substrate, providing a substrate includes: providing a base substrate; and forming a passivation layer on a side of the base substrate close to the driving circuit layer. That is, in this example, the substrate includes the base substrate and the passivation layer.

[0129] In some examples, the substrate includes but is not limited to a glass substrate, a printed circuit board, a resin substrate, etc. For example, the base substrate 101 includes but is not limited to a glass substrate, etc.

[0130] FIG. 17A to FIG. 17C A schematic flow chart of a method for forming a connecting via on a substrate according to an embodiment of the present disclosure is provided. Forming a plurality of connecting vias on a substrate includes: Fig.17A and Fig. 17B As shown, a blind hole 135 is formed on the substrate 101 by laser process; Fig. 17CAs shown, the unetched portion of the base substrate 101 and the passivation layer 102 are etched along the extension direction of the blind hole 135 by an etching process to form a first sub-portion 132 penetrating the base substrate 101 and a second sub-portion 133 penetrating the passivation layer 102. The first connecting via 131 includes a first sub-portion 132 and a second sub-portion 133. In this embodiment, the blind hole 135 is first formed on the base substrate 101 by a laser process, and then the unetched portion of the base substrate 101 is etched by an etching process, so that the laser process will not cause film damage, film bubbling and separation, etc. to the passivation layer 102.

[0131] In some examples, such as Fig. 17C As shown, the average pore size of the second sub-portion 133 is greater than the average pore size of the first sub-portion 132. Therefore, the shape of the first connection via 131 can be approximately anchor-shaped, and the conductive structure located in the first connection via 131 can be approximately anchor-shaped, so that the contact adhesion between the conductive structure in the first connection via 131 and the driving circuit layer 110 can be improved, thereby improving performance stability.

[0132] In some examples, such as Fig. 17C As shown, in the direction from the substrate 100 to the driving circuit layer 110 , the aperture of the first sub-portion 132 remains unchanged, and the aperture of the second sub-portion 133 gradually decreases, and the maximum aperture of the second sub-portion 133 is larger than the aperture of the first sub-portion 132 .

[0133] In some examples, such as Fig. 17C As shown, the cross section of the first sub-portion 132 along the plane perpendicular to the substrate 100 includes a rectangular shape, and the cross section of the second sub-portion 133 along the plane perpendicular to the substrate 100 includes a trapezoidal shape.

[0134] In some examples, such as Fig. 17B As shown, the thickness dimension T0 of the portion of the base substrate 101 that is not punched by the laser process has a value range of 0.05-0.15 mm, thereby ensuring that the base substrate 101 is not penetrated when the laser process punches the base substrate 101 .

[0135] In some examples, such as Fig. 17B As shown, the thickness of the base substrate 101 is T1, the thickness of the passivation layer 102 is T2, the depth of the laser drilling process can be set to 0.85*T1, and the remaining thickness of the base substrate 101 is 0.15*T1 and is etched by an etching process, so that the thickness of the hole etched by the etching process is 0.15T1+T2.

[0136] In some examples, such as Fig. 17CAs shown, the plurality of connection vias 130 further include a plurality of second connection vias 134, and the micro-LED substrate further includes a plurality of micro-driving chips, which are connected to the driving circuit layer 110 through the conductive structures in the plurality of second connection vias 134. It should be noted that the manufacturing process of the second connection vias 134 is the same as that of the first connection vias 131, so that the second connection vias 134 can have the same beneficial effects as those of the first connection vias 131, which will not be described in detail.

[0137] In some examples, the etching process may include dry etching and wet etching. For example, dry etching special gas (special gas) may be used for etching. The embodiments of the present disclosure do not limit dry etching special gas.

[0138] 18A to 18H for Figure 8 The manufacturing method of the micro-LED substrate includes: Fig.18A As shown, a first passivation layer 102 is formed on the first side S1 of the substrate 101. For example, the first passivation layer 102 may be a reverse stress layer. For example, the material of the first passivation layer 102 includes but is not limited to silicon nitride. Fig.18B As shown, the driving circuit layer 110 is formed on the first passivation layer 102 through a coating process, a yellow light process, and an etching process. For example, the material of the driving circuit layer 110 includes but is not limited to copper; Fig. 18C As shown, a passivation layer 119 is deposited on the driving circuit layer 110 by a coating device. For example, the material of the passivation layer 119 includes but is not limited to silicon nitride; Fig.18D As shown, a blind hole 135 is drilled on the second side S2 of the base substrate 101 by laser technology, and the laser drilling is stopped when there is about 0.1 mm left on the base substrate 101; Fig.18E As shown, the unperforated portion of the substrate 101 and the first passivation layer 102 are etched using dry etching gas on the second side S2 of the substrate 101, and finally a Fig.18E The first connecting via 131 and the second connecting via 134; Fig.18F As shown, on the second side S2 of the base substrate 101, a first conductive structure 141 is grown in the first connecting via 131, and a second conductive structure 144 is grown in the second connecting via 134 by electrochemical or gold deposition; Figure 18G As shown, white oil is printed on the second side S2 of the base substrate 101, die is bonded, reflow soldering is performed, and glue is dispensed to obtain the micro-LEDs 120 and the first micro-driving chip 151 arranged in an array on the second side S2 of the base substrate 101; Fig.18HAs shown, on the first side S1 of the base substrate 101, the passivation layer 119 is etched in the bonding area to form a via hole V1 to expose the driving circuit layer 110, and the final product is obtained through a bonding process. For example, the micro LED substrate can be used for light emission or display. 18A to 18H Only one first connection via 131 and one second connection via 134 are schematically shown, but the embodiment of the present disclosure is not limited thereto.

[0139] FIG. 19A to FIG. 19L for Fig.10 The manufacturing method of the micro-LED substrate includes: Fig.19A As shown, a first passivation layer 102 is formed on the first side S1 of the substrate 101. For example, the first passivation layer 102 may be a reverse stress layer. For example, the material of the first passivation layer 102 includes but is not limited to silicon nitride. Fig.19B As shown, a first conductive layer 112 is formed on the first passivation layer 102 through a coating process, a yellow light process, and an etching process. For example, the material of the first conductive layer 112 includes but is not limited to copper; Fig.19C As shown, a second passivation layer 113 is deposited on the first conductive layer 112 by a coating device. For example, the material of the second passivation layer 113 includes but is not limited to silicon nitride; Fig.19D As shown, a patterned insulating layer 114 is formed on the second passivation layer 113 by a yellow light process. For example, the material of the insulating layer 114 includes but is not limited to optical adhesive OC; Fig.19E As shown, a third passivation layer 115 and a via hole V2 are formed through a coating process, a yellow light process, and an etching process; Fig.19F As shown, a second conductive layer 116 is formed on the insulating layer 114 through a coating process, a yellow light process, and an etching process. For example, the material of the second conductive layer 116 includes but is not limited to copper; Figure 19G As shown, a passivation layer 119 is deposited on the driving circuit layer 110 by a coating device. For example, the material of the passivation layer 119 includes but is not limited to silicon nitride, and can also be a composite film layer, for example, a composite film layer of silicon nitride and photoresist OC; Fig.19H As shown, a blind hole 135 is drilled on the second side S2 of the base substrate 101 by laser technology, and the laser drilling is stopped when there is about 0.1 mm left on the base substrate 101; Fig.19I As shown, the unperforated portion of the substrate 101 and the first passivation layer 102 are etched using dry etching gas on the second side S2 of the substrate 101, and finally a Fig.19I The first connecting via 131 and the second connecting via 134; Fig.19JAs shown, on the second side S2 of the base substrate 101, a first conductive structure 141 is grown in the first connecting via 131, and a second conductive structure 144 is grown in the second connecting via 134 by electrochemical or gold deposition; Figure 19K As shown, white oil is printed on the second side S2 of the base substrate 101, die bonding, reflow soldering, and glue dispensing are performed to obtain the micro-LEDs 120 and the first micro-driving chip 151 arranged in an array on the second side S2 of the base substrate 101. Figure 19L As shown, on the first side S1 of the base substrate 101, a passivation layer is etched in the bonding area to form a via hole V1 to expose the driving circuit layer 110, and a final product is obtained through a bonding process. For example, the micro LED substrate can be used for light emission or display. FIG. 19A to FIG. 19L Only one first connection via 131 and one second connection via 134 are schematically shown, but the embodiment of the present disclosure is not limited thereto.

[0140] For example, Fig.12 The micro-LED substrate shown can also be used FIG. 19A to FIG. 19L The production method shown will not be repeated here.

[0141] There are a few points to note:

[0142] (1) In the drawings of the embodiments of the present disclosure, only the structures related to the embodiments of the present disclosure are involved, and other structures can refer to the general design.

[0143] (2) In the absence of conflict, features in the same embodiment or in different embodiments of the present disclosure may be combined with each other.

[0144] The above are only specific embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A micro light emitting diode substrate, comprising: substrate, A driving circuit layer, located on the first side of the substrate; A plurality of micro light emitting diodes are located on a second side of the substrate, wherein the second side and the first side are two opposite sides of the substrate; A plurality of connecting vias passing through the substrate; as well as A plurality of conductive structures are located within the plurality of connecting vias and are arranged one-to-one corresponding to the plurality of connecting vias. Among them, the multiple connecting vias include multiple first connecting vias, the multiple conductive structures include multiple first conductive structures, the multiple first conductive structures are located in the multiple first connecting vias, and the multiple micro-light-emitting diodes are electrically connected to the driving circuit layer through the multiple first conductive structures.

2. The micro-LED substrate according to claim 1, wherein: Each of the micro-light-emitting diodes includes a first pole and a second pole, one end of each of the first conductive structures is connected to the driving circuit layer, and the other end of each of the first conductive structures is exposed on the second side of the substrate to serve as a pad, and the pad is configured to be connected to the first pole or the second pole.

3. The micro-LED substrate according to claim 1, wherein: At least one of the first connecting vias comprises: The first subdivision; and The second sub-section is located at a side of the first sub-section close to the driving circuit layer, The average pore size of the second sub-section is greater than the average pore size of the first sub-section.

4. The micro-LED substrate according to claim 3, wherein: In a direction from the substrate to the driving circuit layer, the aperture of the first sub-section remains unchanged, and the aperture of the second sub-section gradually decreases, and the maximum aperture of the second sub-section is larger than the aperture of the first sub-section.

5. The micro-LED substrate according to claim 4, wherein: A cross section of the first sub-portion along a plane perpendicular to the substrate includes a rectangular shape, and a cross section of the second sub-portion along a plane perpendicular to the substrate includes a trapezoidal shape.

6. The micro-LED substrate according to any one of claims 3 to 5, wherein: The substrate includes a base substrate and a first passivation layer, the first sub-portion is located on the base substrate, and the second sub-portion is located on the first passivation layer.

7. The micro-LED substrate according to any one of claims 1 to 5, wherein: At least one of the first conductive structures comprises: The first conductive part, The second conductive part is located on a side of the first conductive part close to the driving circuit layer, Wherein, an average radial dimension of the second conductive portion is greater than an average radial dimension of the first conductive portion.

8. The micro-LED substrate according to claim 7, wherein: In a direction from the substrate to the driving circuit layer, the radial dimension of the first conductive portion remains unchanged, and the radial dimension of the second conductive portion gradually decreases, and the maximum radial dimension of the second conductive portion is greater than the radial dimension of the first conductive portion.

9. The micro-LED substrate according to claim 8, wherein: A cross section of the first conductive portion along a plane perpendicular to the substrate includes a rectangular shape, and a cross section of the second conductive portion along a plane perpendicular to the substrate includes a trapezoidal shape.

10. The micro-LED substrate according to claim 7, wherein: The substrate includes a base substrate and a first passivation layer, the first conductive portion is located on the base substrate, and the second conductive portion is located on the first passivation layer.

11. The micro-LED substrate according to any one of claims 1 to 5, wherein: The driving circuit layer includes a plurality of signal lines and a plurality of connecting lines, and the micro light emitting diode is connected to the signal lines through the first conductive structure and the connecting lines.

12. The micro-LED substrate according to claim 11, further comprising: A plurality of light-emitting units, each of which comprises a plurality of micro light-emitting diodes; as well as A plurality of first micro-driving chips are arranged corresponding to the plurality of light-emitting units, and each of the first micro-driving chips is configured to drive the corresponding light-emitting unit to emit light. The plurality of connecting vias further include a plurality of second connecting vias, the plurality of conductive structures further include a plurality of second conductive structures, the plurality of second conductive structures are located in the plurality of second connecting vias, and the plurality of first micro-drive chips are connected to the drive circuit layer through the plurality of second conductive structures. The plurality of signal lines include a driving voltage line, a ground line, an operating voltage line and a source address line, the micro light emitting diode is connected to the driving voltage line through the first conductive structure and the connecting line, the first micro driving chip is respectively connected to the ground line, the operating voltage line and the source address line through the second conductive structure and the connecting line, or the first micro driving chip is respectively connected to the ground line, the operating voltage line and the source address line through the second conductive structure, The first micro-driving chip includes an output end, and the micro-light emitting diode is connected to the output end through the first conductive structure and the connecting wire.

13. The micro-LED substrate according to any one of claims 1 to 5, wherein: The driving circuit layer comprises: a first conductive layer, a second passivation layer, located on a side of the first conductive layer away from the substrate; an insulating layer, located on a side of the second passivation layer away from the first conductive layer; a third passivation layer, located on a side of the insulating layer away from the second passivation layer; a second conductive layer, located on a side of the third passivation layer away from the insulating layer; and A plurality of first via holes penetrate the second passivation layer, the insulating layer and the third passivation layer, Among them, the first conductive layer includes multiple connecting lines, the second conductive layer includes multiple signal lines, the multiple micro-light-emitting diodes are connected to the multiple connecting lines of the first conductive layer through the multiple first conductive structures, and the multiple connecting lines of the first conductive layer are connected to the multiple signal lines of the second conductive layer through the multiple first vias.

14. The micro-LED substrate according to claim 13, further comprising: A plurality of light-emitting units, each of which comprises a plurality of micro light-emitting diodes; as well as A plurality of first micro-driving chips are arranged corresponding to the plurality of light-emitting units, and each of the micro-driving chips is configured to drive the corresponding light-emitting unit to emit light. The plurality of connecting vias further include a plurality of second connecting vias, the plurality of conductive structures further include a plurality of second conductive structures, the plurality of second conductive structures are located in the plurality of second connecting vias, and the plurality of first micro-drive chips are connected to the drive circuit layer through the second conductive structures. The plurality of signal lines include a driving voltage line, a ground line, a working voltage line and a source address line, the micro light emitting diode is connected to the driving voltage line through the connecting line of the first conductive structure and the first conductive layer, the first micro driving chip is connected to the ground line, the working voltage line and the source address line respectively through the connecting line of the second conductive structure and the first conductive layer, The first micro-driving chip comprises an output end, and the micro-light emitting diode is connected to the output end through the connecting line.

15. The micro-LED substrate according to claim 13, further comprising: A plurality of pixel units; as well as A plurality of second micro-driving chips are arranged corresponding to the plurality of pixel units, and each of the second micro-driving chips is configured to drive a corresponding pixel unit to display. The plurality of micro-LEDs include a first micro-LED, a second micro-LED and a third micro-LED, the first micro-LED is configured to emit light of a first color, the second micro-LED is configured to emit light of a second color, the third micro-LED is configured to emit light of a third color, and each of the pixel units includes the first micro-LED, the second micro-LED and the third micro-LED. The plurality of connection vias further include a plurality of second connection vias, the plurality of conductive structures further include a plurality of second conductive structures, the plurality of second conductive structures are located in the plurality of second connection vias, and the plurality of second micro-drive chips are connected to the drive circuit layer through the plurality of second conductive structures.

16. The micro-LED substrate according to claim 15, wherein: The plurality of signal lines include a first signal line, a second signal line, a ground line, a working voltage line and a data line, The micro-LED is connected to the first signal line or the second signal line through the connecting lines of the first conductive structure and the first conductive layer, the second micro-driving chip is respectively connected to the ground line, the working voltage line and the data line through the connecting lines of the second conductive structure and the first conductive layer, and the second micro-driving chip includes three output terminals, and the three output terminals are respectively connected to the first micro-LED, the second micro-LED and the third micro-LED of the corresponding pixel unit.

17. The micro-LED substrate according to claims 1-5, further comprising: a fourth passivation layer, located on the first side of the substrate and on a side of the driving circuit layer away from the substrate; The second via hole penetrates the fourth passivation layer to expose the driving circuit layer.

18. A display device comprising the micro light emitting diode substrate according to any one of claims 1 to 17.

19. A method for manufacturing a micro light emitting diode substrate, comprising: providing a substrate; forming a driving circuit layer on a first side of the substrate; forming a plurality of connection vias on the substrate that penetrate the substrate; forming a conductive structure in the connecting via; as well as forming a plurality of micro light emitting diodes on the second side of the substrate, Among them, the first side and the second side are two opposite sides of the substrate, the multiple connecting vias include multiple first connecting vias, the multiple conductive structures include multiple first conductive structures, the multiple first conductive structures are located in the multiple first connecting vias, and the multiple micro-light-emitting diodes are electrically connected to the driving circuit layer through the multiple first conductive structures.

20. The method according to claim 19, wherein: A substrate is provided comprising: providing a substrate base; and A passivation layer is formed on a side of the base substrate close to the driving circuit layer.

21. The method according to claim 20, wherein: Forming a plurality of connecting vias on the substrate comprises: forming a blind hole on the substrate by using a laser process; and The non-perforated portion of the substrate and the passivation layer are etched along the extension direction of the blind hole by an etching process to form a first sub-portion penetrating the substrate and a second sub-portion penetrating the passivation layer. The first connecting via includes the first sub-portion and the second sub-portion.

22. The method according to claim 21, wherein: An average pore size of the second subsection is larger than an average pore size of the first subsection.

23. The micro-LED substrate according to claim 22, wherein: In a direction from the substrate to the driving circuit layer, the aperture of the first sub-section remains unchanged, and the aperture of the second sub-section gradually decreases, and the maximum aperture of the second sub-section is larger than the aperture of the first sub-section.

24. The micro-LED substrate according to claim 22, wherein: A cross section of the first sub-portion along a plane perpendicular to the substrate includes a rectangular shape, and a cross section of the second sub-portion along a plane perpendicular to the substrate includes a trapezoidal shape.

25. The method according to claim 21, wherein: The thickness of the non-perforated portion of the substrate has a value ranging from 0.05 to 0.15 mm.

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