LED light-emitting structure and preparation method thereof, and multicolor LED light-emitting structure and preparation method thereof

Abstract

The invention discloses an LED light-emitting structure and a preparation method thereof, and a multicolor LED light-emitting structure and a preparation method thereof, the LED light-emitting structure comprises a substrate, the substrate is provided with a plurality of through holes penetrating through the substrate, after an LED chip is placed on the substrate, the LED chip is driven to move on the substrate, so that the LED chip is embedded into the through holes, the LED chip is positioned on the surface of the substrate, and the multicolor LED light-emitting structure is obtained. As the requirement on the precision of the LED chip is very low when the LED chip is placed on the substrate at the beginning, the requirement on the position of a single LED chip when the LED chip is transferred can be greatly reduced, the high-precision requirement during traditional mass transfer is avoided, expensive high-precision mass transfer equipment is not needed for transfer, the production efficiency is greatly improved, and the production cost is reduced. And the production cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of light-emitting device manufacturing technology, and in particular to an LED light-emitting structure and its preparation method, and a multi-color LED light-emitting structure and its preparation method. Background Technology

[0002] In the field of display device manufacturing, the key to large-scale commercial production lies in mass transfer technology—that is, how to accurately, efficiently, and stably transfer a massive number of LED chips onto a target substrate. The precision, efficiency, reliability, and yield of the LED chip transfer process directly determine the production cost and market competitiveness of the product.

[0003] Existing technologies typically employ a pick-and-place method, placing each LED chip individually into a predetermined position. When dealing with millions of transfers, this method is inefficient, time-consuming, and requires stringent precision in chip assembly positioning, resulting in high process complexity and manufacturing costs.

[0004] Therefore, it is necessary to improve the existing technology to overcome the aforementioned defects.

[0005] The above content is only used to help understand the technical solution of this application and does not constitute an admission that the above is prior art. Summary of the Invention

[0006] The purpose of this invention is to provide an LED light-emitting structure and its preparation method, and a multi-color LED light-emitting structure and its preparation method, so as to reduce the difficulty of the process.

[0007] To achieve the above-mentioned objectives, in a first aspect, the present invention proposes a method for preparing an LED light-emitting structure, characterized by comprising the following steps:

[0008] S1. A substrate is provided, wherein the substrate has a plurality of through holes penetrating the substrate;

[0009] S2. Place multiple LED chips on a substrate and drive the LED chips to move on the substrate so that the LED chips are embedded in the through hole. The LED chip includes a first electrode and a second electrode located at its two ends respectively. Both electrodes of the LED chip embedded in the through hole are exposed on the substrate.

[0010] S3. Prepare a first wiring layer electrically connected to the first electrode and a second wiring layer electrically connected to the second electrode.

[0011] Furthermore, the through hole has a large end and a small end located at both ends, and in step S2, when multiple LED chips are placed on the substrate, the large end of the through hole faces upward.

[0012] Furthermore, the through hole is a tapered hole;

[0013] The LED chip is adapted to the through hole;

[0014] The thickness of the LED chip is greater than or equal to the thickness of the through hole;

[0015] The LED chip has a large end and a small end at both ends, and its large end cannot pass through the small end of the through hole, or it cannot pass through both the small end and the large end of the through hole.

[0016] Furthermore, step S1 also includes the following steps: providing a support surface located below the through hole of the substrate; in step S2, when the LED chip is embedded in the through hole, it is supported and limited by the support surface.

[0017] Furthermore, the first wiring layer includes a plurality of first driving lines spaced apart along a second direction and a first insulating layer covering the first driving lines, the first driving lines extending along a first direction; the second wiring layer includes a plurality of second driving lines spaced apart along the first direction and a second insulating layer covering the second driving lines, the second driving lines extending along a second direction; the substrate is provided with a plurality of target regions, the target regions corresponding to the overlapping regions of the projections of the first driving lines and the second driving lines along the thickness direction of the substrate; each target region includes at least one via.

[0018] Furthermore, each target region includes multiple through holes, which are distributed in an array or randomly.

[0019] Further, in step S3, the first wiring layer and the second wiring layer cover the surface of the substrate; or,

[0020] In step S3, before preparing the first wiring layer electrically connected to the first electrode and the second wiring layer electrically connected to the second electrode, the method further includes:

[0021] An encapsulation layer is prepared on the substrate to fix the LED chip.

[0022] The first wiring layer and / or the second wiring layer cover the surface of the encapsulation layer.

[0023] Furthermore, in step S2, the LED chip is moved on the substrate by driving the substrate to vibrate; or, the LED chip is moved on the substrate by pushing multiple LED chips with airflow or a pushing member.

[0024] Furthermore, step S2 also includes the following steps:

[0025] LED chips not embedded in the through holes on the substrate are removed by driving the substrate to vibrate, and / or blowing air, and / or flushing with fluid, and / or pushing with a pusher, and / or tilting the substrate.

[0026] Secondly, this invention proposes a method for preparing a multi-color LED light-emitting structure, which further includes the following steps:

[0027] The first layer LED light-emitting structure, the second layer LED light-emitting structure, and the third layer LED light-emitting structure are prepared by the method for preparing the LED light-emitting structure as described in any one of claims 1 to 8. The LED chips located on the same layer emit the same color, and the LED chips located on different layers emit different colors.

[0028] The first layer of LED light-emitting structure, the second layer of LED light-emitting structure, and the third layer of LED light-emitting structure are stacked and connected.

[0029] Furthermore, the first layer LED light-emitting structure, the second layer LED light-emitting structure, and the third layer LED light-emitting structure are all provided with target areas, and each target area has one or more through holes;

[0030] The target areas of the first, second, and third LED light-emitting structures do not overlap in the stacking direction. In the top-view direction, the target areas of the first, second, and third LED light-emitting structures are arranged sequentially, and adjacent target areas of these structures constitute a single colored target area; or...

[0031] The target areas of the first layer LED light-emitting structure, the second layer LED light-emitting structure, and the third layer LED light-emitting structure overlap in the stacking direction, and the overlapping target areas of the first layer LED light-emitting structure, the second layer LED light-emitting structure, and the third layer LED light-emitting structure constitute a colored target area;

[0032] The multicolor LED light-emitting structure may include only one color target area, or it may include multiple color target areas distributed in an array.

[0033] Thirdly, the present invention proposes an LED light-emitting structure, comprising:

[0034] The substrate has multiple through holes penetrating the substrate;

[0035] Multiple LED chips are embedded in the through-hole, and each LED chip includes a first electrode and a second electrode located at both ends of the through-hole. Both the first electrode and the second electrode are exposed on the substrate.

[0036] The first wiring layer is electrically connected to the first electrode;

[0037] The second wiring layer is electrically connected to the second electrode.

[0038] Furthermore, the through hole is a tapered hole, having a large end and a small end located at both ends;

[0039] The LED chip is adapted to the through hole;

[0040] The thickness of the LED chip is greater than or equal to the thickness of the through hole;

[0041] The LED chip has a large end and a small end at both ends, and its large end cannot pass through the small end of the through hole, or it cannot pass through both the small end and the large end of the through hole.

[0042] Furthermore, the first wiring layer includes a plurality of first driving lines spaced apart along a second direction and a first insulating layer covering the first driving lines, the first driving lines extending along a first direction; the second wiring layer includes a plurality of second driving lines spaced apart along the first direction and a second insulating layer covering the second driving lines, the second driving lines extending along a second direction; the substrate is provided with a plurality of target regions, the target regions corresponding to the overlapping regions of the projections of the first driving lines and the second driving lines along the thickness direction of the substrate; each target region includes at least one via.

[0043] Furthermore, the first wiring layer and the second wiring layer cover the surface of the substrate; or,

[0044] An encapsulation layer is provided between the first wiring layer and the substrate, and / or between the second wiring layer and the substrate.

[0045] Fourthly, the present invention proposes a multi-color LED light-emitting structure, which includes a first layer of LED light-emitting structure, a second layer of LED light-emitting structure and a third layer of LED light-emitting structure stacked sequentially from bottom to top. The first layer of LED light-emitting structure, the second layer of LED light-emitting structure and the third layer of LED light-emitting structure are prepared by the method for preparing an LED light-emitting structure as described in any one of claims 1 to 9, or are LED light-emitting structures as described in any one of claims 12 to 15.

[0046] LED chips located on the same layer emit the same color, while LED chips located on different layers emit different colors, and the target areas of the first layer LED light-emitting structure, the second layer LED light-emitting structure, and the third layer LED light-emitting structure may or may not overlap in the stacking direction.

[0047] Compared with the prior art, the present invention has the following beneficial effects: According to at least one embodiment of the present invention, a plurality of through holes penetrating the substrate are provided on the substrate. After the LED chip is placed on the substrate, the LED chip is driven to move on the substrate, so that the LED chip is embedded in the through hole, thereby realizing the positioning of the LED chip on the substrate surface. Since the precision requirement of the LED chip is very low when the LED chip is initially placed on the substrate, the position requirement of the single LED chip can be greatly reduced when transferring the LED chip, avoiding the high precision requirements of traditional mass transfer. It is not necessary to use expensive high-precision mass transfer equipment for transfer, which greatly improves production efficiency and reduces production costs. Attached Figure Description

[0048] Figure 1 This is a cross-sectional schematic diagram of the substrate in some embodiments of the present invention.

[0049] Figure 2 yes Figure 1 The diagram shows a top view of the substrate.

[0050] Figure 3 yes Figure 1 The diagram shows an LED chip embedded in a substrate.

[0051] Figure 4 Is Figure 3 The diagram shows a substrate with a first encapsulation layer on its upper surface.

[0052] Figure 5 Is Figure 4 The diagram shows a first wiring layer on the lower surface of the first encapsulation layer.

[0053] Figure 6 Is Figure 5 The diagram shows a substrate with a second encapsulation layer on its lower surface.

[0054] Figure 7 Is Figure 6 The diagram shows a second wiring layer on the lower surface of the second encapsulation layer.

[0055] Figure 8 This is a schematic diagram of the LED chip portion and the through hole adaptation in some embodiments of the present invention.

[0056] Figure 9This is a schematic diagram of an LED chip embedded in a through hole in some embodiments of the present invention.

[0057] Figure 10 This is a schematic diagram of an LED chip supported by a support plate in some embodiments of the present invention.

[0058] Figure 11 yes Figure 10 The diagram shown illustrates the formation of the first encapsulation layer.

[0059] Figure 12 This is a cross-sectional schematic diagram of the LED light-emitting structure in some embodiments of the present invention.

[0060] Figure 13 This is a schematic diagram of LED chips in some embodiments of the present invention.

[0061] Figure 14 This is a schematic diagram of LED chips in some embodiments of the present invention.

[0062] Figure 15 This is a schematic diagram of LED chips in some embodiments of the present invention.

[0063] Figure 16 This is a three-dimensional schematic diagram of an LED chip according to some embodiments of the present invention.

[0064] Figure 17 yes Figure 16 The diagram shows the front view of the LED chip.

[0065] Figure 18 This is a three-dimensional schematic diagram of an LED chip according to some embodiments of the present invention.

[0066] Figure 19 This is a schematic diagram showing the location of a target region on a substrate in some embodiments of the present invention. The location of the target region is indicated by cross-sectional lines in the figure.

[0067] Figure 20 This is a schematic diagram showing the positions of the first driving line and the second driving line in some embodiments of the present invention. The position of the target area is indicated by cross-sectional lines in the figure.

[0068] Figure 21 This is a schematic diagram of the random distribution of through holes within the target area in some embodiments of the present invention.

[0069] Figure 22 This is a cross-sectional schematic diagram of the LED light-emitting structure in some embodiments of the present invention. In the figure, the wiring layer covers the surface of the substrate.

[0070] Figure 23This is a cross-sectional schematic diagram of the LED light-emitting structure in some embodiments of the present invention. In the figure, a first encapsulation layer is provided between the first wiring layer and the substrate.

[0071] Figure 24 This is a cross-sectional schematic diagram of the first layer LED light-emitting structure in some embodiments of the present invention.

[0072] Figure 25 This is a cross-sectional schematic diagram of the second-layer LED light-emitting structure in some embodiments of the present invention.

[0073] Figure 26 This is a cross-sectional schematic diagram of the third-layer LED light-emitting structure in some embodiments of the present invention.

[0074] Figure 27 This is a cross-sectional schematic diagram of the multicolor light-emitting structure in some embodiments of the present invention.

[0075] Figure 28 This is a schematic diagram of the target area in a top-view direction, showing the first, second, and third layer LED light-emitting structures of some embodiments of the present invention.

[0076] Figure 29 This is a schematic diagram of a multi-color LED light-emitting structure in some embodiments of the present invention when it has an array of colored target areas.

[0077] Figure 30 This is a cross-sectional schematic diagram of the multicolor light-emitting structure in some embodiments of the present invention.

[0078] Figure 31 This is a cross-sectional schematic diagram of a multi-color light-emitting structure in some embodiments of the present invention. In the figure, a transparent insulating film is provided between the LED light-emitting structures of adjacent layers. Detailed Implementation

[0079] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, it should be noted that, for ease of description, only the parts relevant to this application are shown in the accompanying drawings, not the entire structure. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0080] The terms “comprising” and “having”, and any variations thereof, used in this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus.

[0081] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0082] Some embodiments of the present invention provide a method for fabricating an LED light-emitting structure, which includes the following steps:

[0083] S1. Provide substrate 1, for reference Figure 1 and Figure 2 The substrate 1 is provided with a plurality of through holes 10 penetrating the substrate 1. Specifically, the substrate 1 has a first surface 1a and a second surface 1b in the thickness direction, and the through holes 10 penetrate the first surface 1a and the second surface 1b of the substrate 1.

[0084] S2. Place multiple LED chips 2 on the substrate 1, and drive the LED chips 2 to move on the substrate 1, so that the LED chips 2 are embedded in the through holes 10. The state after embedding is shown in the figure. Figure 3 and Figure 9 The LED chip 2 includes a first electrode 20 and a second electrode 21 located at its two ends, one of which is a positive electrode and the other is a negative electrode. When the LED chip 2 is embedded in the through hole 10, both its first electrode 20 and second electrode 21 are exposed on the substrate 1. Specifically, the first electrode 20 is exposed on the first surface 1a of the substrate 1, and the second electrode 21 is exposed on the second surface 1b of the substrate 1. Optionally, the thickness B1 of the LED chip 2 is greater than or equal to the depth H1 of the through hole 10 (in this embodiment, the depth of the through hole 10 is consistent with the thickness of the substrate 1) so that the first electrode 20 and the second electrode 21 can be reliably exposed from the substrate 1.

[0085] S3. For example Figure 7 , Figure 22 and Figure 23 As shown, a first wiring layer 4 electrically connected to the first electrode 20 and a second wiring layer 6 electrically connected to the second electrode 21 are prepared.

[0086] By setting multiple through holes 10 on the surface of the substrate 1, the LED chip 2 can be embedded in the through holes 10, thereby achieving the positioning of the LED chip 2 on the surface of the substrate 1. Since the precision requirement of the LED chip 2 is very low when it is initially placed on the substrate 1, the positioning is completed by moving the LED chip 2 to embed it into the through holes 10 with relatively higher precision. Therefore, the positional requirement of a single LED chip 2 when transferring the LED chip 2 can be greatly reduced, avoiding the high precision requirements of traditional mass transfer. It eliminates the need to use expensive high-precision mass transfer equipment, greatly improving production efficiency and reducing production costs.

[0087] In some embodiments, the through hole 10 has a large end and a small end located at both ends. For example, the through hole 10 is a tapered hole, with the cross-sectional dimension of one end being larger than that of the other end. The end with the larger cross-sectional dimension is the large end, and the end with the smaller cross-sectional dimension is the small end. The cross-section refers to the cross-section perpendicular to the axis of the through hole 10 (which is consistent with the thickness direction of the substrate 1). Figure 1 In the via 10, the larger end is located on the first surface 1a, and the smaller end is located on the second surface 1b. The via 10 can be conical (circular cross-section) or prismatic (polygonal cross-section). Optionally, the LED chip 2 is adapted to the via 10, and both are contoured to ensure that the LED chip 2 can be reliably embedded in the via 10. For example, when the via 10 is conical, the LED chip 2 is frustum-shaped; when the via 10 is pyramidal, the LED chip 2 is frustum-shaped. Since the LED chip 2 is adapted to the via 10, the LED chip 2 can only be embedded in the via 10 with its smaller end facing down. Obviously, the end of the LED chip 2 with the smaller cross-sectional dimension is its small end, and the end with the larger cross-sectional dimension is its large end. The LED chip 2 can be entirely contoured to the via 10, or only partially contoured to the via 10. For example... Figure 8 In the illustrated embodiment, the middle portion of the LED chip 2 is adapted to the through hole 10, and the two ends are not tapered, but columnar (e.g., cylindrical or prismatic), which facilitates the subsequent filling of encapsulation material between adjacent LED chips 2 to form an encapsulation layer.

[0088] It is understandable that the LED chip 2 does not necessarily need to be contoured to the through hole 10 (for example, the cross-section of the through hole 10 can be circular, and the cross-section of the LED chip 2 can be rectangular). As long as the two ends of the LED chip 2 are different sizes, and the larger end of the LED chip 2 cannot enter the smaller end of the through hole 10, while the smaller end of the LED chip 2 can pass through the smaller end of the through hole 10, the LED chip 2 can be inserted into the through hole 10 with its smaller end facing down. After insertion, the smaller and larger ends of the LED chip 2 can be located outside the through hole 10, respectively. Optionally, the larger end of the LED chip 2 cannot pass through the larger end of the through hole 10 to further ensure that the LED chip 2 is not inserted into the through hole 10 in the opposite orientation. Of course, setting the LED chip 2 and the through hole 10 to be contoured can better ensure the relative positional accuracy of the LED chip 2 and the through hole 10, allowing the LED chip 2 to reliably remain vertical and reducing the risk of the LED chip 2 tilting.

[0089] In some embodiments, the center of gravity of the LED chip 2 is set closer to its small end, making it easier to embed into the through hole 10 with the small end facing down. For example, the mass of the small end can be increased by adding a counterweight to the small end or by thickening the second electrode 21.

[0090] It is understood that the through-hole 10 does not necessarily have to be tapered; in other embodiments, such as... Figure 9 As shown, the LED chip 2 is not directly confined by the through-hole 10, but can fall directly out of the through-hole 10. For example, the through-hole 10 can be a straight hole. In this embodiment, as... Figure 9 As shown, in step S1, when providing the substrate 1, the following step is also included: providing a support surface 130 located below the through hole 10 of the substrate 1. The support surface 130 can be, for example, a flat surface of a support plate 13 spaced apart from the substrate 1, or it can be a support plate 13 that supports the substrate 1, such as... Figure 10 As shown, a groove 131 is provided at the position corresponding to the through hole 10 on the support plate 13, and the bottom surface of the groove 131 is the support surface 130. Since the support surface 130 is spaced apart from the substrate 1, when the LED chip 2 enters the through hole 10, it will not fall out of the through hole 10, but will be supported by the support surface 130 and embedded in the through hole 10. Figure 11 As shown, after the first encapsulation layer 3 is fabricated, the support surface 130 can be removed. Schematic diagrams of some embodiments of the LED light-emitting structure after fabrication corresponding to this embodiment are shown below. Figure 12 As shown. It can be understood that the support surface 130 can also be directly attached to the surface of the substrate 1.

[0091] like Figure 19 As shown, a target region 11 is provided on the substrate 1, and each target region 11 is provided with at least one through hole 10. In some embodiments, such as Figure 20As shown, the first wiring layer 4 includes a plurality of first drive lines 41 spaced apart along a second direction, the first drive lines 41 extending along the first direction. The second wiring layer 6 includes second drive lines 61 spaced apart along the first direction, the second drive lines 61 extending along the second direction. Figure 20 In the diagram, the position of the first driving line 41 is indicated by a solid line, and the position of the second driving line 61 is indicated by a dashed line. The first driving line 41 and the second driving line 61 are staggered in the top view direction (i.e., the thickness direction of the substrate 1). Figure 19 and Figure 20 As shown, the target region 11 corresponds to the area where the first driving line 41 and the second driving line 61 intersect, that is, the target region 11 corresponds to the overlapping area (i.e., the intersecting area) of the projections of the first driving line 41 and the second driving line 61 along the thickness direction of the substrate 1. Multiple target regions 11 are formed at the intersection of multiple first driving lines 41 and multiple second driving lines 61. Optionally, the first direction and the second direction are perpendicular and both are perpendicular to the thickness direction of the substrate 1. In this case, multiple target regions 11 are arranged in an array.

[0092] like Figure 7 As shown, the target area 11 has at least one LED chip 2, whose upper and lower electrodes are electrically connected to the first driving line 41 and the second driving line 61, respectively. It can be understood that by applying a positive voltage to the LED chip 2 within the target area 11 through the cooperation of the first driving line 41 and the second driving line 61, independent driving of each target area 11 can be achieved. For example, if the first electrode 20 of the LED chip 2 is positive and the second electrode 21 is negative, a high-level voltage can be applied to the first driving line 41, and the second driving line 61 can be grounded or connected to a low level to drive the LED chip 2 to emit light.

[0093] It is understandable that the LED light-emitting structure may consist of only a first driving line 41 and a second driving line 61, with a target region 11 formed between the first driving line 41 and the second driving line 61.

[0094] In some embodiments, each target area 11 has only one through hole 10 to accommodate one LED chip 2.

[0095] In other embodiments, each target region 11 includes two or more through holes 10, and the multiple through holes 10 can accommodate multiple LED chips 2. Figure 19In the illustrated embodiment, each target region 11 includes four through holes 10. In other embodiments, there may be other numbers of through holes 10. It is understood that when a target region 11 has multiple through holes 10, only one through hole 10 needs to contain an LED chip 2 for the target region 11 to emit light normally. Since it is not necessary for every through hole 10 to contain an LED chip 2, the process requirements are lower. Even if a target region 11 has a damaged LED chip 2, it can still emit light normally as long as a normal LED chip 2 is present, greatly reducing the reliability requirements of the LED chip 2 and increasing the process tolerance. Furthermore, under constant current source driving conditions, when the forward conduction voltage (Vf) of multiple parallel LED chips is similar, the total current output by the constant current source is approximately evenly distributed among the LED chips. Since the total current is constant, the total luminous power and overall brightness remain unchanged regardless of the number of parallel LED chips. In other words, even if the number of LED chips 2 on each target area 11 is different, as long as each target area 11 is driven by a constant current source, the luminous brightness of each target area 11 can be nearly consistent. Of course, more accurate consistency can be further optimized through algorithms. The more luminous LED chips 2 that can emit light within a target area 11, the more uniform the brightness of the pixels corresponding to that target area 11 will be.

[0096] Optionally, when each target region 11 includes multiple through holes 10, the multiple through holes 10 can be arrayed in the target region 11 (see reference). Figure 19 ), or they can be randomly scattered in the target area 11 (see reference). Figure 21 The number of through holes 10 in each target area 11 can be the same or different, which greatly reduces the requirements for the position and accuracy of the through holes 10 when machining them.

[0097] LED chip 2 can be a Micro LED chip or a Mini LED chip. Because there is no need for point-to-point mass transfer, the size of LED chip 2 can be made very small, and the cost of a single LED chip 2 is lower. A large number of LED chips 2 can be randomly distributed in a small target area 11, such as a dozen, dozens, hundreds or even more LED chips 2, thereby improving the reliability and uniformity of light emission.

[0098] Optionally, when the LED chip 2 can pass through the through-hole 10 as a whole, the target area 11 is provided with multiple through-holes 10. It is understood that when the through-hole 10 is tapered, the orientation of the LED chip 2 entering the through-hole 10 is fixed, i.e., the larger end is always up and the smaller end is always down. However, when the through-hole 10 is straight, the orientation of the LED chip 2 within the through-hole 10 can vary. For example, some LED chips 2 may have their first electrode 20 on top, while others may have their second electrode 21 on top. When the first electrode 20 needs to be on top, other LED chips 2 will not function. By providing multiple through-holes 10, the number of LED chips 2 in the target area is increased, greatly increasing the probability that at least one LED chip 2 has the correct orientation, thus helping to ensure the reliability of the process.

[0099] The probability that the LED chip 2 is correctly positioned within the via 10 can be increased in several ways. For ease of explanation, the LED chip 2 with the correct orientation will be referred to as an effective LED chip, and the LED chip 2 with the incorrect orientation will be referred to as an ineffective LED chip. The target electrode of the LED chip 2 with the correct orientation is on top, and the following description will use the first electrode 20 as the target electrode.

[0100] In some embodiments, the center of gravity of the LED chip 2 is set close to the second electrode 21. This makes the LED chip 2 more stable when its second electrode 21 is facing downwards, thus significantly increasing the probability that the second electrode 21 of the LED chip 2 will face downwards. As a possible example, refer to... Figure 13 The LED chip 2 includes a metal mass block 210 connected to its second electrode 21. The center of gravity of the LED chip 2 is changed by adding the metal mass block 210. As a possible example, such as... Figure 14 As shown, the second electrode 21 of the LED chip 2 is widened and / or thickened to bring its center of gravity closer to the second electrode 21. As a possible example, such as... Figure 15 As shown, the cross-sectional area of ​​the end where the second electrode 21 of the LED chip 2 is located is larger than the cross-sectional area of ​​the end where the first electrode 20 is located, and its overall shape is smaller at the top and larger at the bottom, so that its center of gravity is close to the second electrode 21. It can be understood that the above examples can be used in combination to further ensure the effect.

[0101] In some embodiments, the LED chip 2 is in the shape of a cuboid or a cube, and includes at least two sets of electrode pairs. The second electrode 21 of the two sets of electrode pairs is located on two adjacent surfaces of the LED chip 2. Similarly, each of the two second electrodes 20 is provided with a first electrode 20, and the first electrode 20 and the second electrode 21 of the same electrode pair are located on two opposite surfaces of the LED chip 2. Figure 16 and Figure 17A schematic diagram is shown when two sets of electrodes are provided on the LED chip 2. Because the number of second electrodes 21 on the surface of the LED chip 2 increases, the probability of the second electrode 21 being downward-facing can be significantly increased. Specifically, assuming that the probability of each side of the LED chip 2 facing downwards is the same, the probabilities of having a downward-facing second electrode 21 are one-sixth and one-third when the second electrode 21 is provided on only one side and on both sides, respectively. Optionally, as... Figure 18 As shown, the LED chip 2 includes three sets of electrode pairs. The second electrode 21 of the three sets of electrode pairs is located on three adjacent surfaces of the LED chip 2. Assuming that the probability of each surface of the LED chip 2 facing down is the same, when three sets of electrode pairs are set, the probability of the second electrode 21 of the LED chip 2 facing down is one in half, which greatly increases the probability. When the number of randomly distributed LED chips 2 in the target area 11 is 10, the probability of having a valid LED chip 2 can be greater than 99.9%. If combined with the aforementioned center of gravity adjustment or other methods, the probability can be further improved. For example, the center of gravity of the LED chip 2 can be set close to one of the second electrodes 21, or it can be set close to the connection position of two or three second electrodes 21.

[0102] In some embodiments, the LED chip 2 is cylindrical, the through hole 10 is a circular hole, and the first electrode 20 and the second electrode 21 of the LED chip 2 are located at the two ends of the cylinder, respectively. In this way, after the LED chip 2 is embedded in the through hole 10, there are only two possibilities: the first electrode 20 is on top or the first electrode 21 is on the bottom, which greatly increases the probability of correct orientation. Optionally, the LED chip 2 is flattened cylindrical to make it more stable when its plane is on the bottom, reducing the possibility of it rolling.

[0103] Understandably, the probability of the second electrode 21 being on the bottom can also be increased in other ways. For example, the probability can be increased by applying an external magnetic field: a small amount of magnetic metal can be deposited on the side of the second electrode 21 or unidirectional magnetic particles can be adhered, and a magnetic field can be applied below the substrate 1 to align the LED chips 2 in the correct orientation. Alternatively, the probability can be increased by applying an external sound field or electric field.

[0104] In some embodiments, the substrate 1 has through holes 10 only in its target area 11. This means that LED chips 2 are not present in other locations on the substrate 1, which is more conducive to improving the transparency of the LED light-emitting structure. For example, it can be made into a transparent display screen with better transparency. In other embodiments, the entire surface of the substrate 1 is provided with through holes 10. It is understood that LED chips 2 not located in the target area 11 are not energized and therefore do not affect the light emission of the LED light-emitting structure.

[0105] In some embodiments, such as Figure 7As shown, the first wiring layer 4 further includes a first insulating layer 40 covering the first driving line 41, which encapsulates the first driving line 41 for better protection. The second wiring layer 6 further includes a second insulating layer 60 covering the second driving line 61 for better protection. The first wiring layer 4 and the second wiring layer 6 can be fabricated, for example, using an RDL (Reverse Diode) method.

[0106] In some embodiments, in step S3, the first wiring layer 4 and the second wiring layer 6 cover the surface of the substrate 1, such as... Figure 22 As shown, Figure 22 In this design, the thickness B1 of the LED chip 2 is equal to the thickness H1 of the through-hole 10, and its first electrode 20 and second electrode 21 are flush with the first surface 1a and the second surface 1b of the substrate 1, respectively. It is understood that the thickness B1 of the LED chip 2 can also be greater than the thickness H1 of the through-hole 10, causing the first electrode 20 and the second electrode 21 of the LED chip 2 to protrude to the outside of the substrate 1. Optionally, the substrate 1 has hot-melt properties (similar to hot-melt adhesive), allowing the LED chip 2 embedded in the hole to be bonded and encapsulated by heating, thus fixing the LED chip 2 within the substrate 1 to facilitate the fabrication of the first wiring layer 4 and the second wiring layer 6. For example, the substrate 1 uses a low-temperature non-adhesive material that can be hot-melted after heating to complete the encapsulation, such as ETFE material (ethylene-tetrafluoroethylene copolymer) or silicone film. For example, the substrate 1 can be made of conventional materials (such as glass, silicon wafers, ceramics, or thin films). Then, a liquid hot melt adhesive (such as UV B-Stage adhesive) is coated (e.g., spin-coated) on the surface of the substrate 1 (at least the inner surface of the through hole 10). The adhesive is then "pre-cured" by UV / heating, and the adhesive changes from liquid to solid dry film (extremely thin, for example, less than 1 μm), completely losing its adhesiveness. This makes it easy to insert the LED chip 2 into the through hole 10. The solid dry film can soften and melt again after heating and become adhesive, thus bonding and wrapping the LED chip 2 inside the hole. After cooling, it becomes solid and fixes the LED chip 2.

[0107] In some embodiments, step S3, before preparing the first wiring layer 4 electrically connected to the first electrode 20 and the second wiring layer 6 electrically connected to the second electrode 21, further includes the following step: preparing an encapsulation layer on the substrate 1 to fix the LED chip 2. The encapsulation layer can be formed, for example, by coating with a molding compound, which can fix the LED chip 2 and provide protection. In this case, the first wiring layer 4 and / or the second wiring layer 6 cover the surface of the encapsulation layer. For example, Figure 23In the illustrated embodiment, the thickness B1 of the LED chip 2 is greater than the thickness H1 of the through-hole 10. The first electrode 20 of the LED chip 2 protrudes to the outside of the substrate 1, and the second electrode 21 is flush with the second surface 1b. A first encapsulation layer 3 is formed on the first surface 1a of the substrate 1, a first wiring layer 4 covers the first encapsulation layer 3, and a second wiring layer 6 covers the second surface 1b of the substrate 1. For example, Figure 7 In the illustrated embodiment, the thickness B1 of the LED chip 2 is greater than the thickness H1 of the through hole 10. The first electrode 20 and the second electrode 21 of the LED chip 2 both protrude to the outside of the substrate 1. A first encapsulation layer 3 and a second encapsulation layer 5 are formed on the first surface 1a and the second surface 1b of the substrate 1, respectively. A first wiring layer 4 covers the first encapsulation layer 3, and a second wiring layer 6 covers the second encapsulation layer 5.

[0108] It is understood that when a first encapsulation layer 3 and a second encapsulation layer 5 are present, the first encapsulation layer 3 and the second encapsulation layer 5 can be fabricated in one step or in two separate steps. Optionally, when the first encapsulation layer 3 and the second encapsulation layer 5 are fabricated in two separate steps, step S3 may include the following steps:

[0109] like Figure 4 As shown, a first encapsulation layer 3 is prepared on the first surface 1a of the exposed first electrode 20 on the substrate 1, such as... Figure 5 As shown, a first wiring layer 4 is fabricated on the surface of the first encapsulation layer 3. Figure 6 As shown, a second encapsulation layer 5 is prepared on the second surface 1b of the exposed second electrode 21 on the substrate 1, such as... Figure 7 As shown, a second wiring layer 6 is formed on the surface of the second encapsulation layer 5. It is understood that the process sequence in step S3 is not unique; for example, the first encapsulation layer 3 and the second encapsulation layer 5 can be formed first, followed by the formation of the first wiring layer 4 and the second wiring layer 6. Further optionally, after the first encapsulation layer 3 is formed and before the second encapsulation layer 5 is formed, the following step is included: flipping the substrate 1 so that the second surface 1b of the exposed second electrode 21 of the substrate 1 faces upwards. This allows the operation to always be performed above the substrate 1, which is more convenient and makes it easier to ensure the quality of the process. It is understood that due to the presence of the first encapsulation layer 3, even if the substrate 1 is flipped, the LED chip 2 will not fall out of the through-hole 10.

[0110] It is understood that in some embodiments, the first encapsulation layer 3 and the second encapsulation layer 5 can be two independent encapsulation layers located on two separate surfaces of the substrate 1. In other embodiments, the first encapsulation layer 3 and the second encapsulation layer 5 can also be integral, both covering the entire substrate 1, for example, by potting adhesive onto the outside of the substrate 1 to complete a complete encapsulation body encapsulating the substrate 1. Optionally, when the LED encapsulation structure has encapsulation layers, before preparing the first wiring layer 4 on the surface of the first encapsulation layer 3, the upper surface of the first encapsulation layer 3 is thinned (e.g., by grinding) to expose the first electrode 20 of the LED chip 2. In this way, when preparing the first wiring layer 4, the top electrode of the LED chip 2 can be reliably electrically connected to the first driving line 41. Similarly, before preparing the second wiring layer 6 on the surface of the second encapsulation layer 5, the outer surface of the second encapsulation layer 5 is thinned (e.g., by grinding) to expose the second electrode 21 of the LED chip 2. In this way, when preparing the second wiring layer 6, the second electrode 21 of the LED chip 2 can be reliably electrically connected to the second driving line 61. It is understandable that if the first electrode 20 and the second electrode 21 of the LED chip 2 can be reliably exposed during the preparation of the encapsulation layer, the step of thinning the encapsulation layer can be omitted.

[0111] Optionally, the initial thickness (thickness before thinning) of the first electrode 20 and the second electrode 21 is not less than 10 μm, so that after the thinning process, as many or even all of the electrodes of the LED chip 2 as possible can be reliably exposed, ensuring electrical connection with the driving line.

[0112] It is understandable that when the substrate 1 has hot-melt properties (e.g., it is made of hot-melt material or coated with hot-melt adhesive), in step S3, before preparing the first wiring layer 4 electrically connected to the first electrode 20 and the second wiring layer 6 electrically connected to the second electrode 21, the following steps are also included: heating the substrate 1 to bond and encapsulate the LED chip 2 located in the through hole 10, and then cooling the substrate 1 to fix the LED chip 2. After the LED chip 2 is fixed, it may be necessary to continue to set an encapsulation layer, or it may not be set. For example, when the LED chip 2 protrudes significantly from the substrate 1, an encapsulation layer may be set. It is understandable that after the LED chip 2 is fixed by the substrate 1, the LED chip 2 is less likely to shift in position during subsequent processes, which helps to ensure the smooth progress of subsequent processes.

[0113] In some embodiments, in step S2, the LED chip 2 is driven to move on the substrate 1 by vibrating the substrate 1, thereby randomly embedding it into the through hole 10. In other embodiments, multiple LED chips 2 are moved on the substrate 1 by airflow. For example, multiple LED chips 2 can be randomly scattered on the first surface 1a of the substrate 1, and then an air source is driven to blow air onto the surface of the substrate 1, causing multiple LED chips 2 to move on the substrate 1. When the LED chip 2 moves to the through hole 10, it can be embedded into the through hole 10. In still other embodiments, the LED chip 2 is mixed in a liquid and moves on the substrate 1 with the liquid. In yet another embodiment, multiple LED chips 2 are driven to move on the substrate 1 by a pusher. For example, multiple LED chips 2 can be randomly scattered or piled on the first surface 1a of the substrate 1, and then the multiple LED chips 2 can be moved by a pusher, so that the LED chip 2 can be embedded into the through hole 10. Optionally, the pusher is flexible to prevent damage to the surfaces of the LED chip 2 and the substrate 1. Further, the end of the pusher is provided with fine bristles, making the pusher itself resemble a fine brush. The movement of the LED chip 2 via these bristles better protects the LED chip 2. By controlling the size and stroke of the pusher, the entire surface of the substrate 1 can be swept in a single movement, improving work efficiency.

[0114] It is understandable that as many through holes 10 as possible can have LED chips 2 by repeating step S2 multiple times.

[0115] In some embodiments, step S2 further includes the following step: removing the LED chips 2 not embedded in the through holes 10 on the substrate 1. For example, the LED chips 2 not embedded in the through holes 10 can be moved to the edge of the substrate 1 and fall off from the edge of the substrate 1 by driving the substrate 1 to vibrate. Alternatively, the LED chips 2 not embedded in the through holes 10 can be blown away from the surface of the substrate 1 by blowing air. Another example is that the LED chips 2 not embedded in the through holes 10 can be carried away from the surface of the substrate 1 by fluid flushing. Yet another example is that the LED chips 2 not embedded in the through holes 10 can be swept away from the surface of the substrate 1 by pushing with a pusher. Finally, the LED chips 2 not embedded in the through holes 10 can be rolled off the surface of the substrate 1 under the action of gravity by tilting the substrate 1.

[0116] It is understandable that when the substrate 1, the first encapsulation layer 3, the second encapsulation layer 5, the first insulating layer 40 and the second insulating layer 60 are all made of transparent materials, and the first driving line 41 and the second driving line 42 are made of transparent materials or have a thin line width, the LED light-emitting structure as a whole is transparent and can be used as a transparent display screen for double-sided display.

[0117] In some embodiments, the substrate 1 is made of glass, silicon wafer, ceramic, or thin film. The thin film is made of an insulating material, such as polyimide (PI, Kapton), polyester film (PET, Mylar, ETFE, silicone film), polycarbonate (PC), or polyethylene terephthalate (PEN).

[0118] This invention also proposes an LED light-emitting structure, which can be obtained by the LED light-emitting structure fabrication method described above. The structure of the LED light-emitting structure has been described in detail above; the following is a brief description of its main components.

[0119] In some embodiments, such as Figure 7 , Figure 22 and Figure 23 As shown, the LED light-emitting structure includes a substrate 1, multiple LED chips 2, a first wiring layer 4, and a second wiring layer 6.

[0120] The substrate 1 has multiple through holes 10 penetrating the substrate 1, and LED chips 2 are embedded in the through holes 10. As described above, the substrate 1 has a target region 11, and the target region 11 has at least one through hole 10. Not all through holes 10 in each target region 11 need to have LED chips 2; only one LED chip 2 is required for normal light emission. The LED chip 2 is a vertical LED chip, with a first electrode 20 and a second electrode 21 at its two ends, respectively. In the illustrated embodiment, the larger end of the LED chip 2 has the first electrode 20, and the smaller end has the second electrode 21. The thickness B1 of the LED chip 2 is greater than or equal to the thickness H1 of the through hole 10, and its two ends are exposed at the two ends of the through hole 10, respectively.

[0121] The first wiring layer 4 is electrically connected to the first electrode 20. As described above, the first wiring layer 4 may include a plurality of first driving lines 41 spaced apart along a second direction and a first insulating layer 40 covering the first driving lines 41. The first driving lines 41 extend along a first direction and are electrically connected to the first electrodes 20 of the LEDs in some target areas 11.

[0122] The second wiring layer 6 is electrically connected to the second electrode 21. As described above, the second wiring layer 6 may include a plurality of second driving lines 61 spaced apart along a first direction and a second insulating layer 60 covering the second driving lines 61. The second driving lines 61 extend along a second direction and are electrically connected to the second electrodes 21 of the LEDs in some target areas 11. The LED chip 2 connected between the first driving line 41 and the second driving line 61 is driven to emit light through cooperation between the first driving line 41 and the second driving line 61.

[0123] In some embodiments, such as Figure 22As shown, the first wiring layer 4 and the second wiring layer 6 cover the surface of the substrate 1. In other embodiments, an encapsulation layer is provided between the first wiring layer 4 and the substrate 1, and / or between the second wiring layer 6 and the substrate 1, for example, Figure 22 A first encapsulation layer 3 is shown to be disposed between the first wiring layer 4 and the substrate 1. Figure 7 The diagram shows a first encapsulation layer 3 and a second encapsulation layer 5 disposed between the first wiring layer 4, the second wiring layer 6, and the substrate 1. The first encapsulation layer 3 is connected to the first surface 1a of the exposed first electrode 20 of the substrate 1, and the second encapsulation layer 5 is connected to the second surface 1b of the exposed second electrode 21 of the substrate 1. The wiring layers cover the corresponding encapsulation layers.

[0124] Optionally, the LED chip 2 is adapted to the through-hole 10, for example, by contouring the two. In some embodiments, the through-hole 10 is tapered, and the LED chip 2 is also tapered. The first electrode 20 is located at its large end, and the second electrode 21 is located at its small end.

[0125] It is understandable that when there are multiple first drive lines 41 and second drive lines 61, multiple array-distributed target regions 11 can be formed. Alternatively, there can be only one first drive line 41 and one second drive line 61, in which case only one target region 11 can be formed.

[0126] It is understood that other embodiments or structural details of the LED light-emitting structure can be found in the description above in the preparation method of the LED light-emitting structure, and will not be repeated here.

[0127] This invention also proposes a method for preparing a multi-color LED light-emitting structure, which includes the following steps:

[0128] A1. As Figures 24 to 26 As shown, the first LED light-emitting structure 80, the second LED light-emitting structure 81, and the third LED light-emitting structure 82 are fabricated. For example, they can be fabricated using the LED light-emitting structure fabrication method described above. LED chips 2 located on the same layer emit the same color, while LED chips 2 located on different layers emit different colors. For example, the first LED light-emitting structure 80, the second LED light-emitting structure 81, and the third LED light-emitting structure 82 contain red LED chips, green LED chips, and blue LED chips, respectively.

[0129] A2. Stack and connect the first layer LED light-emitting structure 80, the second layer LED light-emitting structure 81, and the third layer LED light-emitting structure 82. For example, the first layer LED light-emitting structure 80, the second layer LED light-emitting structure 81, and the third layer LED light-emitting structure 82 are stacked sequentially from bottom to top.

[0130] Because a multi-color LED light-emitting structure has multiple layers of LED light-emitting structures that can emit light of different colors, it is possible to create a wider variety of colors of light by controlling each layer of LED light-emitting structure to emit light individually or simultaneously.

[0131] The first-layer LED light-emitting structure 80, the second-layer LED light-emitting structure 81, and the third-layer LED light-emitting structure 82 each have an array of target areas 11. Each target area 11 has one or more through holes 10. The projections of the target areas 11 of the first-layer LED light-emitting structure 80, the second-layer LED light-emitting structure 81, and the third-layer LED light-emitting structure 82 in the stacking direction can overlap or not overlap (non-overlapping results in higher luminous efficiency). When overlapping, the light mixing effect is better; when not overlapping, it can prevent the upper LED light-emitting structure from blocking the light emitted by the lower LED light-emitting structure, thus increasing the emitted brightness. (This is correct.)

[0132] Figure 27 , Figure 28 and Figure 29 The diagram shows a schematic of the target areas 11 of the three-layer LED light-emitting structure when their projections do not overlap. In a top-view orientation, the target areas 11 of the first-layer LED light-emitting structure 80, the second-layer LED light-emitting structure 81, and the third-layer LED light-emitting structure 82 are arranged sequentially. This arrangement brings the three different colored target areas 11 relatively close, facilitating the mixing and emission of different colors of light. For illustrative purposes, Figure 28 and Figure 29 In the diagram, target areas 11a, 11b, and 11c represent the target areas 11 of the first layer LED light-emitting structure 80, the second layer LED light-emitting structure 81, and the third layer LED light-emitting structure 82, respectively. The target areas of each layer of light-emitting structure are distinguished by different line types.

[0133] The target areas 11 of the adjacent first-layer LED light-emitting structure 80, second-layer LED light-emitting structure 81, and third-layer LED light-emitting structure 82 constitute a colored target area 12. The colored target area 12 is a colored pixel that can be controlled to emit different colors of light. A multi-color LED light-emitting structure may include only one colored target area 12 (e.g., ...). Figure 28 A colored target area 12 is shown, at which point the multi-color LED light-emitting structure can be used as an LED light bead. For example... Figure 29As shown, the multi-color LED light-emitting structure can also include multiple colored target areas 12. In this case, the multi-color LED light-emitting structure can be used as a display screen to display richer content (such as displaying videos, pictures, and text). The first-layer LED light-emitting structure 80, the second-layer LED light-emitting structure 81, and the third-layer LED light-emitting structure 82 all have multiple arrayed target areas 11. In the first direction, between every two adjacent target areas 11a of the first-layer LED light-emitting structure 80, there is a target area 11b of the second-layer LED light-emitting structure 81 and a target area 11c of the third-layer LED light-emitting structure 82. When the LED chips of the first-layer LED light-emitting structure 80, the second-layer LED light-emitting structure 81, and the third-layer LED light-emitting structure 82 emit red light, green light, and blue light respectively, a cyclic arrangement of red light target area 11a, green light target area 11b, and blue light target area 11c is formed. The multi-color LED light-emitting structure includes multiple arrayed colored target areas 12.

[0134] Figure 30 A schematic diagram is shown showing the projected overlap of the target regions 11 of the three-layer LED light-emitting structure. The overlapping target regions 11 of the first-layer LED light-emitting structure 80, the second-layer LED light-emitting structure 81, and the third-layer LED light-emitting structure 82 constitute a colored target region 12. Similarly, a multi-color LED light-emitting structure may include only one colored target region 12, or it may include multiple arrayed colored target regions 12.

[0135] In some embodiments, such as Figure 31 As shown, in step A2, when the first LED light-emitting structure 80, the second LED light-emitting structure 81, and the third LED light-emitting structure 82 are stacked and connected, a transparent insulating film 7 is also placed between each layer of LED light-emitting structure to improve the insulation performance between adjacent LED light-emitting structures. Optionally, the material of the transparent insulating film 7 can be polyimide (PI, Kapton), polyester film (PET, Mylar), polycarbonate (PC), or polyethylene terephthalate (PEN), etc.

[0136] It is understood that other embodiments or structural details of the LED light-emitting structure can be found in the description above, and will not be repeated here.

[0137] This invention also proposes a multi-color LED light-emitting structure, such as... Figure 27As shown, it includes a first layer of LED light-emitting structure 80, a second layer of LED light-emitting structure 81, and a third layer of LED light-emitting structure 82 stacked sequentially from bottom to top. The first layer of LED light-emitting structure 80, the second layer of LED light-emitting structure 81, and the third layer of LED light-emitting structure 82 can be prepared by the LED light-emitting structure preparation method described above, or can be the LED light-emitting structure described above. LED chips 2 located on the same layer emit the same color, while LED chips 2 located on different layers emit different colors. In the illustrated embodiment, the LED chips 2 on the first layer of LED light-emitting structure 80, the second layer of LED light-emitting structure 81, and the third layer of LED light-emitting structure 82 emit red light, green light, and blue light, respectively.

[0138] Because a multi-color LED light-emitting structure has multiple layers of LED light-emitting structures that can emit light of different colors, it is possible to create a wider variety of colors of light by controlling each layer of LED light-emitting structure to emit light individually or simultaneously.

[0139] In some embodiments, the first layer LED light-emitting structure 80, the second layer LED light-emitting structure 81, and the third layer LED light-emitting structure 82 each have an array of target regions 11. Each target region 11 has at least one through-hole 10, and the projections of the target regions 11 of the first layer LED light-emitting structure 80, the second layer LED light-emitting structure 81, and the third layer LED light-emitting structure 82 in the stacking direction do not overlap. In the top view direction, the target regions 11 of the first layer LED light-emitting structure 80, the second layer LED light-emitting structure 81, and the third layer LED light-emitting structure 82 are arranged sequentially. In this way, the three target regions 11 of different colors are relatively close, which is more conducive to mixing and emitting different colors of light.

[0140] like Figures 27 to 29 As shown, the target areas 11 of the adjacent first-layer LED light-emitting structure 80, second-layer LED light-emitting structure 81, and third-layer LED light-emitting structure 82 constitute a colored target area 12. The colored target area 12 is a colored pixel, which can be controlled to emit different colors of light. A multi-color LED light-emitting structure may include only one colored target area 12; in this case, the multi-color LED light-emitting structure can be used as a single LED bulb. Alternatively, a multi-color LED light-emitting structure may include multiple colored target areas 12; in this case, the multi-color LED light-emitting structure can be used as a display screen to display richer content (such as videos, images, and text). Figure 29As shown, the first-layer LED light-emitting structure 80, the second-layer LED light-emitting structure 81, and the third-layer LED light-emitting structure 82 each have multiple arrayed target regions 11. In a first direction, between every two adjacent target regions 11a of the first-layer LED light-emitting structure 80, there is a target region 11b of the second-layer LED light-emitting structure 81 and a target region 11c of the third-layer LED light-emitting structure 82. When the LED chips of the first-layer LED light-emitting structure 80, the second-layer LED light-emitting structure 81, and the third-layer LED light-emitting structure 82 emit red light, green light, and blue light respectively, a cyclic arrangement of red light target region 11a, green light target region 11b, and blue light target region 11c is formed. The multi-color LED light-emitting structure includes multiple arrayed colored target regions 12, enabling it to be used as a display screen or other display device.

[0141] In some embodiments, such as Figure 31 As shown, a transparent insulating film 7 is provided between each of the two adjacent LED light-emitting structures to improve the insulation performance between adjacent LED light-emitting structures.

[0142] It is understood that other embodiments or structural details of the LED light-emitting structure can be found in the description above, and will not be repeated here.

[0143] It should be noted that, in the absence of conflict, the various embodiments described herein can be combined with each other to obtain more implementation schemes.

[0144] The above are merely specific embodiments of the present invention, and any improvements made based on the concept of the present invention shall be considered within the scope of protection of the present invention.

Claims

1. A method for preparing an LED light-emitting structure, characterized in that, Includes the following steps: S1. Provide a substrate (1), the substrate (1) having a plurality of through holes (10) penetrating the substrate (1). S2. Place multiple LED chips (2) on a substrate (1) and drive the LED chips (2) to move on the substrate (1) so that the LED chips (2) are embedded in the through hole (10). The LED chip (2) includes a first electrode (20) and a second electrode (21) located at its two ends respectively. Both electrodes of the LED chip (2) embedded in the through hole (10) are exposed on the substrate (1). S3. Prepare a first wiring layer (4) electrically connected to the first electrode (20) and a second wiring layer (6) electrically connected to the second electrode (21).

2. The method for preparing the LED light-emitting structure as described in claim 1, characterized in that, The through hole (10) has a large end and a small end at both ends. In step S2, when multiple LED chips (2) are placed on the substrate (1), the large end of the through hole (10) faces upward.

3. The method for preparing the LED light-emitting structure as described in claim 2, characterized in that, The through hole (10) is a tapered hole; The LED chip (2) is adapted to the through hole (10); The thickness of the LED chip (2) is greater than or equal to the thickness of the through hole (10); The LED chip (2) has a large end and a small end at both ends, and its large end cannot pass through the small end of the through hole (10), or it cannot pass through the small end and the large end of the through hole (10).

4. The method for preparing the LED light-emitting structure as described in claim 1, characterized in that, Step S1 further includes the following steps: providing a support surface (13) below the through hole (10) of the substrate (1); in step S2, when the LED chip (2) is embedded in the through hole (10), it is supported and limited by the support surface (13).

5. The method for preparing the LED light-emitting structure as described in claim 1, characterized in that, The first wiring layer (4) includes a plurality of first driving lines (41) spaced apart along a second direction and a first insulating layer (40) covering the first driving lines (41). The first driving lines (41) extend along a first direction. The second wiring layer (6) includes a plurality of second driving lines (61) spaced apart along a first direction and a second insulating layer (60) covering the second driving lines (61). The second driving lines (61) extend along a second direction. The substrate (1) is provided with a plurality of target regions (11). The target regions (11) correspond to the overlapping regions of the projections of the first driving lines (41) and the second driving lines (61) along the thickness direction of the substrate (1). Each target region (11) includes at least one via (10).

6. The method for preparing the LED light-emitting structure as described in claim 5, characterized in that, Each target region (11) includes multiple through holes (10), which are either arrayed or randomly distributed.

7. The method for preparing the LED light-emitting structure as described in claim 1, characterized in that, In step S3, the first wiring layer (4) and the second wiring layer (6) cover the surface of the substrate (1); or, In step S3, before preparing the first wiring layer (4) electrically connected to the first electrode (20) and the second wiring layer (6) electrically connected to the second electrode, the following steps are also included: An encapsulation layer is prepared on the substrate (1) to fix the LED chip (2); The first wiring layer (4) and / or the second wiring layer (6) cover the surface of the encapsulation layer.

8. The method for preparing the LED light-emitting structure according to any one of claims 1 to 7, characterized in that, In step S2, the LED chip (2) is driven to move on the substrate (1) by driving the substrate (1) to vibrate; or, the LED chip (2) is driven to move on the substrate (1) by pushing multiple LED chips (2) with airflow or a pusher.

9. The method for preparing the LED light-emitting structure according to any one of claims 1 to 7, characterized in that, Step S2 further includes the following steps: LED chips (2) not embedded in the through holes (10) on the substrate (1) are removed by driving the substrate (1) to vibrate, and / or blowing air, and / or flushing with fluid, and / or pushing with a pusher, and / or tilting the substrate (1).

10. A method for preparing a multicolor LED light-emitting structure, characterized in that, Includes the following steps: The first layer LED light-emitting structure (80), the second layer LED light-emitting structure (81) and the third layer LED light-emitting structure (82) are prepared by the method of preparing LED light-emitting structure as described in any one of claims 1 to 8. The LED chips (2) located on the same layer have the same light-emitting color, and the LED chips (2) located on different layers have different light-emitting colors. The first layer LED light-emitting structure (80), the second layer LED light-emitting structure (81), and the third layer LED light-emitting structure (82) are stacked and connected.

11. The method for preparing a multicolor LED light-emitting structure as described in claim 10, characterized in that, The first layer LED light-emitting structure (80), the second layer LED light-emitting structure (81) and the third layer LED light-emitting structure (82) are all provided with target areas (11), and each target area (11) has one or more through holes (10). The target areas (11) of the first layer LED light-emitting structure (80), the second layer LED light-emitting structure (81), and the third layer LED light-emitting structure (82) do not overlap in the stacking direction. In the top view direction, the target areas (11) of the first layer LED light-emitting structure (80), the second layer LED light-emitting structure (81), and the third layer LED light-emitting structure (82) are arranged sequentially, and the target areas (11) of adjacent first layer LED light-emitting structures (80), second layer LED light-emitting structures (81), and third layer LED light-emitting structures (82) constitute a colored target area (12); or, The target areas (11) of the first layer LED light-emitting structure (80), the second layer LED light-emitting structure (81) and the third layer LED light-emitting structure (82) overlap in the stacking direction, and the overlapping target areas (11) of the first layer LED light-emitting structure (80), the second layer LED light-emitting structure (81) and the third layer LED light-emitting structure (82) constitute a colored target area (12). The multicolor LED light-emitting structure may include only one color target area (12), or may include multiple array-distributed color target areas (12).

12. An LED light-emitting structure, characterized in that, include: The substrate (1) has a plurality of through holes (10) penetrating the substrate (1). Multiple LED chips (2) are embedded in the through hole (10) and include a first electrode (20) and a second electrode (21) located at both ends thereon. The first electrode (20) and the second electrode (21) are both exposed on the substrate (1). The first wiring layer (4) is electrically connected to the first electrode (20); The second wiring layer (6) is electrically connected to the second electrode (21).

13. The LED light-emitting structure as described in claim 12, characterized in that, The through hole (10) is a tapered hole with a large end and a small end located at both ends; The LED chip (2) is adapted to the through hole (10); The thickness of the LED chip (2) is greater than or equal to the thickness of the through hole (10); The LED chip (2) has a large end and a small end at both ends, and its large end cannot pass through the small end of the through hole (10), or it cannot pass through the small end and the large end of the through hole (10).

14. The LED light-emitting structure as described in claim 13, characterized in that, The first wiring layer (4) includes a plurality of first driving lines (41) spaced apart along a second direction and a first insulating layer (40) covering the first driving lines (41). The first driving lines (41) extend along a first direction. The second wiring layer (6) includes a plurality of second driving lines (61) spaced apart along a first direction and a second insulating layer (60) covering the second driving lines (61). The second driving lines (61) extend along a second direction. The substrate (1) is provided with a plurality of target regions (11). The target regions (11) correspond to the overlapping regions of the projections of the first driving lines (41) and the second driving lines (61) along the thickness direction of the substrate (1). Each target region (11) includes at least one via (10).

15. The LED light-emitting structure as described in claim 12, characterized in that, The first wiring layer (4) and the second wiring layer (6) cover the surface of the substrate (1); or, An encapsulation layer is provided between the first wiring layer (4) and the substrate (1), and / or between the second wiring layer (6) and the substrate (1).

16. A multi-color LED light-emitting structure, characterized in that, It includes a first layer of LED light-emitting structure (80), a second layer of LED light-emitting structure (81) and a third layer of LED light-emitting structure (82) stacked from bottom to top. The first layer of LED light-emitting structure (80), the second layer of LED light-emitting structure (81) and the third layer of LED light-emitting structure (82) are prepared by the method of preparing LED light-emitting structure as described in any one of claims 1 to 9, or are LED light-emitting structures as described in any one of claims 12 to 15. LED chips (2) located on the same layer emit the same color, LED chips (2) located on different layers emit different colors, and the target areas (11) of the first layer LED light-emitting structure (80), the second layer LED light-emitting structure (81) and the third layer LED light-emitting structure (82) overlap or do not overlap in the stacking direction.

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