A micro-light-emitting element array, a transfer method of micro-light-emitting elements, and a display device

Abstract

The present invention discloses a micro-light-emitting element array, a transfer method of micro-light-emitting elements, and a display device. The micro-light-emitting element array includes: a substrate, an anchoring structure, a plurality of micro-light-emitting elements to be transferred, and a tethering structure; the anchoring structure is disposed between the substrate and the tethering structure; the tethering structure includes a first connecting portion, and the first connecting portion is located between two adjacent micro-light-emitting elements to be transferred and connects the two adjacent micro-light-emitting elements to be transferred; the anchoring structure includes a first anchoring portion, and a surface of the first anchoring portion facing the first connecting portion includes a first site and a second site; in a direction perpendicular to the surface of the substrate, a distance between the first site and the first connecting portion is D1, a distance between the second site and the first connecting portion is D2, and the first site is located on a side of the second site closer to the micro-light-emitting element to be transferred; D1 < D2. Through the above solution, the size of the residual structure at the edge of the light-emitting element after massive transfer can be reduced, avoiding affecting the subsequent manufacturing process of the display device.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of display technologies, and in particular, to a micro light-emitting element array, a transfer method of micro light-emitting elements, and a display device. Background Art

[0002] Mini Light-Emitting Diode (Mini LED) and Micro Light-Emitting Diode (Micro LED) display technologies refer to technologies that use a micro light-emitting diode array integrated at a high density on a substrate as pixels to achieve light-emitting display. With the development of display technologies, the applications of Mini LED display devices or Micro LED display devices in the market are gradually increasing.

[0003] The manufacturing process of Mini LED display devices or Micro LED display devices includes a mass transfer process of chips. Currently, after the mass transfer process of chips, a relatively large area of tether structures remains on the chips, which has an adverse impact on subsequent processes. Summary of the Invention

[0004] In view of this, the present invention provides a micro light-emitting element array, a transfer method of micro light-emitting elements, and a display device to reduce the size of the tether structures remaining on the micro light-emitting elements after mass transfer, reduce the influence of the remaining structures on subsequent process manufacturing, and improve the reliability of the display device.

[0005] In a first aspect, embodiments of the present invention provide a micro light-emitting element array, including:

[0006] a substrate, an anchoring structure, a plurality of micro light-emitting elements to be transferred, and a tether structure; the anchoring structure is disposed between the substrate and the tether structure, and the tether structure connects the micro light-emitting elements to be transferred;

[0007] The tether structure includes a first connecting portion, and the first connecting portion is located between two adjacent micro light-emitting elements to be transferred and connects the two adjacent micro light-emitting elements to be transferred;

[0008] The anchoring structure includes a first anchoring portion, a positive projection of the first anchoring portion on the substrate is located within a positive projection of the first connecting portion on the substrate, and a surface of the first anchoring portion facing the first connecting portion includes a first site and a second site; in a direction perpendicular to the surface of the substrate, a distance between the first site and the first connecting portion is D1, a distance between the second site and the first connecting portion is D2, and the first site is located on a side of the second site closer to the micro light-emitting element to be transferred; wherein, D1 < D2.

[0009] In a second aspect, embodiments of the present invention further provide a transfer method of micro light-emitting elements, including:

[0010] A micro-light-emitting element array is provided; the micro-light-emitting element array includes a substrate, an anchoring structure, a plurality of micro-light-emitting elements to be transferred, and a tethering structure; the anchoring structure is disposed between the substrate and the tethering structure, and the tethering structure connects the micro-light-emitting elements to be transferred; the tethering structure includes a first connecting portion, and the first connecting portion is located between two adjacent micro-light-emitting elements to be transferred and connects the two adjacent micro-light-emitting elements to be transferred; the anchoring structure includes a first anchoring portion, and the orthographic projection of the first anchoring portion on the substrate is located within the orthographic projection of the first connecting portion on the substrate. One side surface of the first anchoring portion facing the first connecting portion includes a first site and a second site; in a direction perpendicular to the surface of the substrate, the distance between the first site and the first connecting portion is D1, and the distance between the second site and the first connecting portion is D2. The first site is located on the side of the second site closer to the micro-light-emitting element to be transferred; wherein, D1 < D2;

[0011] Use a transfer device to grasp the micro-light-emitting element to be transferred and press down, so that the first connecting portion breaks at the area in contact with the first site of the first anchoring portion;

[0012] Pick up the micro-light-emitting element to be transferred and transfer the micro-light-emitting element to be transferred to a receiving substrate.

[0013] In a third aspect, an embodiment of the present invention further provides a display device prepared by using the transfer method of the micro-light-emitting element in the second aspect of the present invention.

[0014] In the embodiments of the present application, the micro-light-emitting element array includes: a substrate, an anchoring structure, a plurality of micro-light-emitting elements to be transferred, and a tethering structure; the anchoring structure is disposed between the substrate and the tethering structure, and the tethering structure connects the micro-light-emitting elements to be transferred; the tethering structure includes a first connecting portion, and the first connecting portion is located between two adjacent micro-light-emitting elements to be transferred and connects the two adjacent micro-light-emitting elements to be transferred; the anchoring structure includes a first anchoring portion, and the orthographic projection of the first anchoring portion on the substrate is located within the orthographic projection of the first connecting portion on the substrate. One side surface of the first anchoring portion facing the first connecting portion includes a first site and a second site; in a direction perpendicular to the surface of the substrate, the distance between the first site and the first connecting portion is D1, and the distance between the second site and the first connecting portion is D2. The first site is located on the side of the second site closer to the micro-light-emitting element to be transferred; wherein, D1 < D2. Through the above solution, in the mass transfer process, the size of the residual structure remaining on the edge of the light-emitting element after the first connecting portion breaks is small, which can greatly reduce the influence of the residual structure on the subsequent process, improve the yield of the subsequent process, and thus improve the reliability of the display device. Description of the Drawings

[0015] Figure 1 It is a schematic structural diagram of a micro-light-emitting element array in the related art;

[0016] Figure 2 Schematic structural diagram of a micro-light-emitting element in the related art;

[0017] Figure 3 Schematic partial cross-sectional structure diagram of a micro-light-emitting element array provided by an embodiment of the present invention;

[0018] Figure 4 is Figure 3 Enlarged structural diagram at A;

[0019] Figure 5 Schematic preparation process diagram of a micro-light-emitting element array provided by an embodiment of the present invention;

[0020] Figure 6 Schematic partial cross-sectional structure diagram of another micro-light-emitting element array provided by an embodiment of the present invention;

[0021] Figure 7 Schematic structural diagram of a first anchoring portion provided by an embodiment of the present invention;

[0022] Figure 8 Schematic structural diagram of another first anchoring portion provided by an embodiment of the present invention;

[0023] Figure 9 Schematic top view structure diagram of a micro-light-emitting element array provided by an embodiment of the present invention;

[0024] Figure 10 is Figure 9 Cross-sectional structure diagram along the B-B' direction;

[0025] Figure 11 Schematic partial cross-sectional structure diagram of yet another micro-light-emitting element array provided by an embodiment of the present invention;

[0026] Figure 12 Flowchart of a transfer method of a micro-light-emitting element provided by an embodiment of the present invention;

[0027] Figure 13 Schematic structural diagram of a display device provided by an embodiment of the present invention. Detailed implementation manners

[0028] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. Additionally, it should be noted that for the convenience of description, only parts related to the present invention are shown in the drawings, rather than all the structures.

[0029] Figure 1 Schematic structural diagram of a micro-light-emitting element array in the related art, as Figure 1As shown in the figure, in the related art, a micro-light-emitting element array includes a plurality of micro-light-emitting elements 3 to be transferred arranged in an array on a substrate 1. Adjacent two micro-light-emitting elements 3 to be transferred are connected and fixed through a tether structure 4. A first anchoring portion 20 in the anchoring structure 2 contacts a portion of the tether structure 4 between adjacent two micro-light-emitting elements 3 to be transferred. When transferring the micro-light-emitting elements 3 to be transferred, the tether structure 4 is broken by the acting force of the first anchoring portion 20 on the tether structure 4, and the breaking point s is located in the area of the tether structure 4 that contacts the first anchoring portion 20, so as to pick up a plurality of independent micro-light-emitting elements 3 to be transferred. In this setting mode, the area of the region where the first anchoring portion 20 contacts the tether structure 4 is relatively large, and the contact region is close to the middle of adjacent two micro-light-emitting elements 3 to be transferred, so that the breaking point s is located in the middle of adjacent two micro-light-emitting elements 3 to be transferred. As a result, after breaking, the size of the portion of the tether structure 4 remaining on the edge of the micro-light-emitting element 3 to be transferred is relatively large. After the tether structure is broken, the obtained independent micro-light-emitting element 3 to be transferred is defined as the micro-light-emitting element 3, Figure 2 is a schematic structural diagram of a micro-light-emitting element in the related art. Refer to Figure 2 , after breaking the tether structure 4, there is a relatively large residual structure r (within the dashed box) at the top edge of the micro-light-emitting element 3. In various process steps after mass transfer, such as when subsequently coating glue to prepare the encapsulation structure on the light-emitting side of the display panel, the glue material will be blocked by the residual structure r, resulting in problems such as uneven coating and the presence of air bubbles, thereby affecting the reliability of the display device.

[0030] Based on the above defects of the related art, the present application provides a micro-light-emitting element array, including:

[0031] a substrate, an anchoring structure, a plurality of micro-light-emitting elements to be transferred, and a tether structure; the anchoring structure is arranged between the substrate and the tether structure, and the tether structure connects the micro-light-emitting elements to be transferred;

[0032] The tether structure includes a first connecting portion, and the first connecting portion is located between adjacent two micro-light-emitting elements to be transferred and connects the adjacent two micro-light-emitting elements to be transferred;

[0033] The anchoring structure includes a first anchoring portion, and the orthographic projection of the first anchoring portion on the substrate is located within the orthographic projection of the first connecting portion on the substrate. One side surface of the first anchoring portion facing the first connecting portion includes a first site and a second site; in the direction perpendicular to the surface of the substrate, the distance between the first site and the first connecting portion is D1, and the distance between the second site and the first connecting portion is D2. The first site is located on the side of the second site closer to the micro-light-emitting element to be transferred; wherein, D1 < D2.

[0034] Through the above technical solution, in the mass transfer process, the first site of the first anchoring portion breaks the first connecting portion of the tethering structure. Since the first site is closer to the edge of the micro-light-emitting element to be transferred, the size of the residual structure remaining on the edge of the micro-light-emitting element after the first connecting portion breaks is small, thereby greatly reducing the influence of the residual structure on subsequent process steps, improving the yield of subsequent processes, and further improving the reliability of the display device.

[0035] The above is the core idea of the present invention. Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0036] Figure 3 FIG. is a partial cross-sectional structure schematic diagram of a micro-light-emitting element array provided by an embodiment of the present invention. As Figure 4 is Figure 3 an enlarged structure schematic diagram at A, referring to Figure 3 and Figure 4 , the micro-light-emitting element array provided by the embodiment of the present application includes: a substrate 1, an anchoring structure 2, a plurality of micro-light-emitting elements 3 to be transferred, and a tethering structure 4; the anchoring structure 2 is disposed between the substrate 1 and the tethering structure 4, and the tethering structure 4 connects the micro-light-emitting elements 3 to be transferred; the tethering structure 4 includes a first connecting portion 40, and the first connecting portion 40 is located between two adjacent micro-light-emitting elements 3 to be transferred and connects the two adjacent micro-light-emitting elements 3 to be transferred; the anchoring structure 2 includes a first anchoring portion 20, and the orthographic projection of the first anchoring portion 20 on the substrate 1 is located within the orthographic projection of the first connecting portion 40 on the substrate 1. One side surface of the first anchoring portion 20 facing the first connecting portion 40 includes a first site a and a second site b; in the direction perpendicular to the surface of the substrate 1, the distance between the first site a and the first connecting portion 40 is D1, and the distance between the second site b and the first connecting portion 40 is D2. The first site a is located on the side of the second site b close to the micro-light-emitting element 3 to be transferred; wherein, D1 < D2.

[0037] Specifically, as Figure 3 and Figure 4As shown, the micro-light-emitting element array is composed of a substrate 1, an anchoring structure 2 disposed on one side of the substrate 1, a micro-light-emitting element 3 to be transferred, and a tethering structure 4 disposed on the side of the anchoring structure 2 away from the substrate 1. The substrate 1 can be a transfer substrate, such as sapphire, glass, resin, or quartz, etc., but is not limited thereto. The micro-light-emitting element 3 to be transferred can be a Mini LED chip or a Micro LED chip, but is not limited thereto. The tethering structure 4 includes a plurality of first connecting portions 40. The first connecting portions 40 are disposed between any two adjacent micro-light-emitting elements 3 to be transferred. The first connecting portions 40 can connect and fix the adjacent two micro-light-emitting elements 3 to be transferred, so that the tethering structure 4 connects and fixes a plurality of micro-light-emitting elements 3 to be transferred, avoiding the phenomenon of the micro-light-emitting elements 3 to be transferred falling off before mass transfer. Among them, the connection point of the first connecting portion 40 and the micro-light-emitting element 3 to be transferred is located at the edge of the micro-light-emitting element 3 to be transferred on the side away from the substrate 1.

[0038] Further, continuing to refer to Figure 3 and Figure 4 , the anchoring structure 2 includes a plurality of first anchoring portions 20, and the orthographic projection of the first connecting portion 40 on the plane where the substrate 1 is located covers the orthographic projection of the first anchoring portion 20 on the plane where the substrate 1 is located. It can also be understood that the orthographic projection of the first anchoring portion 20 on the substrate 1 is located between the orthographic projections of two adjacent micro-light-emitting elements 3 to be transferred on the substrate 1. Among them, in the embodiment of the present application, there are a first site a and a second site b on the surface of the first anchoring portion 20 facing the first connecting portion 40. For two adjacent micro-light-emitting elements 3 connected by the same first connecting portion 40, in the direction parallel to the plane where the substrate 1 is located, the distance between the first site a on the first anchoring portion 20 corresponding to the first connecting portion 40 and any one of the adjacent micro-light-emitting elements 3 is less than the distance between the second site b and the micro-light-emitting element 3. The direction parallel to the plane where the substrate 1 is located can be defined as the horizontal direction. In this setting method, compared with the second site b, the first site a is closer to the edge of the micro-light-emitting element 3 to be transferred in the horizontal direction.

[0039] Meanwhile, the distance D1 between the first site a on the first anchoring portion 20 and the first connecting portion 40 is less than the distance D2 between the second site b and the first connecting portion 40. The distance between the first site a (or the second site b) and the first connecting portion 40 refers to the distance between the first site a (or the second site b) and the first connecting portion 40 in the direction perpendicular to the plane of the substrate 1, which can also be understood as the straight-line distance between the first site a (or the second site b) and the first connecting portion 40. In this way, the distance between the first site a and the first connecting portion 40 is closer. When using the transfer device to grasp the micro light-emitting element 3 to be transferred and press it down (a process in the mass transfer process), the first site a of the first anchoring portion 20 will first contact the first connecting portion 40. When the first site a contacts the first connecting portion 40, the second site b does not contact the first connecting portion 40. The area of the first connecting portion 40 that contacts the first site a is more likely to be stressed and broken. Since the first site a is closer to the edge of the micro light-emitting element 3 to be transferred, the distance between the fracture point s and the edge of the micro light-emitting element 3 to be transferred is relatively close. After the first connecting portion 40 breaks in the area contacting the first site a, the size of the structure remaining on the edge of the micro light-emitting element 3 to be transferred is small, which can greatly reduce the influence of the remaining structure on the subsequent process, improve the yield of the subsequent process, and thus improve the reliability of the display device. The plane where the substrate 1 is located can be understood as the surface of the substrate 1, and the direction perpendicular to the surface of the substrate 1 is the direction perpendicular to the plane where the substrate 1 is located.

[0040] Wherein, for the specific set values of the distance D1 between the first site a and the first connecting portion 40 and the distance D2 between the second site b and the first connecting portion 40, the embodiments of the present invention do not make limitations, and those skilled in the art can set them according to actual needs. In addition, the first site a and the second site b shown in the figure are only for illustration, and the first site a and the second site b can refer to any sites on the surface of the first anchoring portion 20 facing the first connecting portion 40 that satisfy their positional relationship.

[0041] In the embodiments of the present application, the micro-light-emitting element array includes: a substrate, an anchoring structure, a plurality of micro-light-emitting elements to be transferred, and a tethering structure; the anchoring structure is disposed between the substrate and the tethering structure, and the tethering structure connects the micro-light-emitting elements to be transferred; the tethering structure includes a first connecting portion, and the first connecting portion is located between two adjacent micro-light-emitting elements to be transferred and connects the two adjacent micro-light-emitting elements to be transferred; the anchoring structure includes a first anchoring portion, and the orthographic projection of the first anchoring portion on the substrate is located within the orthographic projection of the first connecting portion on the substrate. One surface of the first anchoring portion facing the first connecting portion includes a first site and a second site; in a direction perpendicular to the surface of the substrate, the distance between the first site and the first connecting portion is D1, and the distance between the second site and the first connecting portion is D2. The first site is located on the side of the second site closer to the micro-light-emitting element to be transferred; wherein, D1 < D2. Through the above solution, in the mass transfer process, the first site of the first anchoring portion breaks the first connecting portion of the tethering structure. Since the first site is closer to the edge of the micro-light-emitting element to be transferred, the size of the residual structure remaining on the edge of the micro-light-emitting element to be transferred after the first connecting portion breaks is small, thereby greatly reducing the influence of the residual structure on the subsequent process, improving the yield of the subsequent process, and further improving the reliability of the display device.

[0042] Optionally, the embodiments of the present application do not limit the preparation method of the micro-light-emitting element array, and any process flow known to those skilled in the art can be used to prepare the micro-light-emitting element array in the present application. Figure 5 FIG. is a schematic flow chart of the preparation of a micro-light-emitting element array provided by an embodiment of the present invention. Below, in conjunction with Figure 5 An exemplary introduction of an optional preparation method of the micro-light-emitting element array is provided.

[0043] First, referring to Figure 5 FIG. (a) therein, a growth substrate 5 is provided. A buffer layer 6 may be deposited on one surface of the growth substrate 5. The buffer layer 6 plays a buffering role. A plurality of micro-light-emitting elements 3 arranged in an array are provided on the side of the buffer layer 6 facing away from the growth substrate 5. Among them, the growth substrate 5 may be any suitable substrate, including but not limited to a silicon-based substrate, a sapphire substrate, a gallium selenide substrate, an indium phosphide substrate, or a gallium arsenide substrate. The buffer layer 6 may be a gallium nitride buffer layer, but is not limited thereto. The micro-light-emitting element 3 to be transferred may include a stacked structure, such as a stacked semiconductor material layer and an electrode layer, etc. Among them, a first inorganic layer 7 may be provided between two adjacent micro-light-emitting elements 3 to be transferred. The first inorganic layer 7 is used to connect two adjacent micro-light-emitting elements 3 to be transferred. The first inorganic layer 7 may be silicon oxide, silicon nitride, etc., but is not limited thereto.

[0044] Further, referring to Figure 5In Figure (b), an anchoring structure 2 is prepared on the side of the micro light-emitting element 3 to be transferred away from the substrate 1. When forming the first anchoring portion 20 of the anchoring structure 2, an anchoring layer with a certain thickness can be first deposited on the surface of the first inorganic layer 7 between adjacent micro light-emitting elements 3 to be transferred. Subsequently, part of the anchoring layer in contact with the first inorganic layer 7 is removed through an etching process such as dry etching, so as to form a first site a and a second site b on the surface of the anchoring layer facing the first inorganic layer 7, obtaining the first anchoring portion 20, and the first site a and the second site b satisfy the positional relationship in the above embodiment. Further, the substrate 1 is covered on the side of the first anchoring portion 20 away from the micro light-emitting element 3 to be transferred.

[0045] Further, referring to Figure 5 Figures (c) and (d), the growth substrate 5 can be peeled off by a laser lift-off process, and part of the buffer layer 6 overlapping the area between any two adjacent micro light-emitting elements 3 to be transferred along the direction perpendicular to the surface of the substrate 1 is etched away, so as to expose part of the first inorganic layer 7. Subsequently, a second inorganic layer 8 can be prepared at least on the side of the first inorganic layer 7 away from the anchoring structure 2, and the second inorganic layer 8 can be the first connecting portion 40 of the tethering structure 4 in the above embodiment. Thus, the micro light-emitting element array in the embodiment of the present application can be prepared, and the relative positional relationships in the embodiments shown in Figure 3 and Figure 4 are satisfied among the first connecting portion 40, the first site a, the second site b, and the micro light-emitting element 3 to be transferred.

[0046] Of course, the preparation method of the micro light-emitting element array is not limited to this, and any preparation process flow capable of obtaining the micro light-emitting element array in the embodiment of the present application is within the scope of the technical solutions protected by the embodiment of the present application.

[0047] Optionally, continuing to refer to Figure 3 and Figure 4 , in a possible embodiment, two adjacent micro light-emitting elements 3 to be transferred include a first micro light-emitting element 31 to be transferred and a second micro light-emitting element 32 to be transferred, the first site a is located on the side of the second site b close to the first micro light-emitting element 31; the surface of the first anchoring portion 20 facing the first connecting portion 40 further includes a third site c; the third site c is located on the side of the second site b close to the second micro light-emitting element 32; in the direction perpendicular to the surface of the substrate 1, the distance between the third site c and the first connecting portion 40 is D3; wherein, D3 < D2.

[0048] Specifically, as shown in Figure 3 and Figure 4As shown in the figure, in this embodiment, two adjacent micro light-emitting elements 3 to be transferred connected by the same first connecting portion 40 can be divided into a first micro light-emitting element 31 to be transferred and a second micro light-emitting element 32 to be transferred. The horizontal direction can refer to the direction from the first micro light-emitting element 31 to the second micro light-emitting element 32 to be transferred. Along the horizontal direction, the distance between the first position point a on the first anchoring portion 20 and the first micro light-emitting element 31 to be transferred is less than the distance between the second position point b and the first micro light-emitting element 31 to be transferred. That is, compared with the second position point b, the first position point a is closer to the first micro light-emitting element 31 to be transferred.

[0049] Further, there is also a third position point c on the surface of the first anchoring portion 20 facing the first connecting portion 40. Along the horizontal direction, the distance between the third position point c and the second micro light-emitting element 32 to be transferred is less than the distance between the second position point b and the second micro light-emitting element 32 to be transferred. That is, compared with the second position point b, the third position point c is closer to the second micro light-emitting element 32 to be transferred. Thus, on the surface of the first anchoring portion 20 facing the first connecting portion 40, the orthogonal projection of the second position point b on the first connecting portion 40 is located in the middle of the first connecting portion 40, and the orthogonal projections of the first position point a and the third position point c on the first connecting portion 40 are located at both ends of the first connecting portion 40 close to the micro light-emitting element 3 to be transferred. It should be noted that the middle of the first connecting portion 40 described here refers to the middle area of the first connecting portion 40 in the direction from the first micro light-emitting element 31 to be transferred to the second micro light-emitting element 32 to be transferred.

[0050] At the same time, the distance D3 between the third position point c on the first anchoring portion 20 and the first connecting portion 40 is less than the distance D2 between the second position point b and the first connecting portion 40. Thus, compared with the second position point b, the third position point c is closer to the first connecting portion 40. When using the transfer device to grasp the micro light-emitting element 3 to be transferred and press it down, the first position point a and the third position point c of the first anchoring portion 20 will first contact the first connecting portion 40. When the first position point a and the third position point c respectively contact the first connecting portion 40, the second position point b does not contact the first connecting portion 40. The area of the first connecting portion 40 in contact with the first position point a and the third position point c is more likely to be stressed and broken. Since both the first position point a and the third position point c are close to the edge of the micro light-emitting element 3 to be transferred, the distances between the two breaking points s and the edges of the two micro light-emitting elements 3 to be transferred are both relatively close. After the first connecting portion 40 breaks in the area in contact with the first position point a and the third position point c, the sizes of the residual structures remaining on the edges of the first micro light-emitting element 31 and the second micro light-emitting element 32 are both small, further avoiding the adverse effects of the residual structures on the edges of each micro light-emitting element 3 to be transferred on the subsequent manufacturing process.

[0051] It should be noted that the division of the direction from the first micro light-emitting element 31 to be transferred to the second micro light-emitting element 32 to be transferred is not fixed, but is carried out on the basis of determining a certain first connecting portion 40. A certain micro light-emitting element 3 to be transferred can be either the first micro light-emitting element 31 to be transferred or the second micro light-emitting element 32 to be transferred. For example, for Figure 3 the first connecting portion 40 on the left side in, the leftmost micro light-emitting element 3 to be transferred is the first micro light-emitting element 31 to be transferred, and the middle micro light-emitting element 3 to be transferred is the second micro light-emitting element 32 to be transferred; for Figure 3 the first connecting portion 40 on the right side in, the middle micro light-emitting element 3 to be transferred is the first micro light-emitting element 31 to be transferred, and the rightmost micro light-emitting element 3 to be transferred is the second micro light-emitting element 32 to be transferred.

[0052] Among them, for the specific value of the distance D3 between the third site c and the first connecting portion 40, the embodiments of the present invention do not make a limitation, and those skilled in the art can set it according to actual needs.

[0053] Exemplarily, in an alternative embodiment, D1 = D3 can be set.

[0054] Specifically, as Figure 4 shown, as an alternative embodiment, the distance D3 between the third site c and the first connecting portion 40 can be set to be equal to the distance D1 between the first site a and the first connecting portion 40. In this setting method, the structure of the first anchoring portion 20 is relatively regular and the manufacturing process is relatively simple; in addition, during the process of using the transfer device to grasp the micro light-emitting element 3 to be transferred and press it down, the first site a and the third site c contact the first connecting portion 40 at the same time, so that the area of the first connecting portion 40 in contact with the first site a and the second site b is simultaneously stressed and broken, ensuring the balance of the acting forces at both ends of the first anchoring portion 20 and the first connecting portion 40, and further ensuring the breaking effect of the first connecting portion 40.

[0055] Of course, in other embodiments not shown, the distance D3 between the third site c and the first connecting portion 40 can also be set to be different from the distance D1 between the first site a and the first connecting portion 40 according to actual needs, and the present application will not elaborate on this.

[0056] Exemplarily, reference can be continued to Figure 4 , in a possible embodiment, along the direction parallel to the surface of the substrate 1, the distance L1 between the first site a and the second site b is equal to the distance L2 between the third site c and the second site b.

[0057] Specifically, as Figure 4As shown, the horizontal distance L1 between the first site a and the second site b can be set to be the same as the horizontal distance L2 between the third site c and the second site b. In this way, when the projection of the second site b on the first connecting portion 40 is located exactly in the middle of the first connecting portion 40, the horizontal distance between the first site a and the first micro light-emitting element 31 to be transferred is equal to the horizontal distance between the third site c and the second micro light-emitting element 32 to be transferred in the horizontal direction. After the first connecting portion 40 breaks, the sizes of the structures remaining on the edges of the first micro light-emitting element 31 and the second micro light-emitting element 32 are basically the same and are relatively small.

[0058] Optionally, in other alternative embodiments, those skilled in the art can set the distances between the first site a, the second site b, and the third site c according to actual needs, and the present application will not introduce them in detail one by one. Exemplarily, the first site a and the third site c can be respectively located at the two side edges of the first anchoring portion 20 along the direction from the first micro light-emitting element 31 to the second micro light-emitting element 32, so that the first site a is as close as possible to the edge of the first micro light-emitting element 31, and the third site c is as close as possible to the edge of the second micro light-emitting element 32.

[0059] It should be noted that the first site a, the second site b, and the third site c can be understood as three regions on the surface of the first anchoring portion 20 facing the first connecting portion 40. Along the direction from the first micro light-emitting element 31 to the second micro light-emitting element 32, the surface of the first anchoring portion 20 facing the first connecting portion 40 as a whole shows a trend of first decreasing and then increasing. In other words, the surface of the first anchoring portion 20 on the side facing the first connecting portion 40 is not a flat surface, and it can be at least divided into a first sub-surface 21, a second sub-surface 22, and a third sub-surface 23. The distances between the first sub-surface 21 and the first connecting portion 40 and between the third sub-surface 23 and the first connecting portion 40 are both smaller than the distance between the second sub-surface 22 and the first connecting portion 40, and along the direction from the first micro light-emitting element 31 to the second micro light-emitting element 32, the second sub-surface 22 is located between the first sub-surface 21 and the third sub-surface 23. The side of the first anchoring portion 20 close to the first connecting portion 40 is in a concave-like shape with both ends protruding and the middle being concave in the horizontal direction. The first site a can be any site on the first sub-surface 21, the second site b can be any site on the second sub-surface 22, and the third site c can be any site on the third sub-surface 23.

[0060] In the above embodiments, the first connecting portion 40 of the tether structure 4 and the first anchoring portion 20 of the anchoring structure 2 are arranged in one-to-one correspondence, but this is not limited in reality. Exemplarily, Figure 6 This is a schematic partial cross-sectional structure diagram of another micro light-emitting element array provided by an embodiment of the present invention. Refer to Figure 6, in an alternative embodiment, a first connection portion 40 of the tether structure 4 can be provided corresponding to a plurality of first anchoring portions 20.

[0061] Figure 6 In the illustrated embodiment, two adjacent micro light-emitting elements 3 to be transferred connected by the same first connection portion 40 can still be divided into a first micro light-emitting element 31 to be transferred and a second micro light-emitting element 32 to be transferred. Different from Figure 4 the illustrated embodiment, in this embodiment, the first anchoring portion 20 only includes a first site a and a second site b, and the same first connection portion 40 corresponds to two first anchoring portions 20. As Figure 6 shown, the two first anchoring portions 20 corresponding to the same first connection portion 40 can be divided into a first anchoring portion 20a and a first anchoring portion 20b. Among them, the first site a on the first anchoring portion 20a is located on the side of the second site b close to the first micro light-emitting element 31 to be transferred. Along the direction from the first micro light-emitting element 31 to the second micro light-emitting element 32 to be transferred, the surface of the first anchoring portion 20a facing the first connection portion 40 shows a downward trend; the first site a on the first anchoring portion 20b is located on the side of the second site b close to the second micro light-emitting element 32 to be transferred. Along the direction from the second micro light-emitting element 32 to be transferred to the first micro light-emitting element 31, the surface of the first anchoring portion 20b facing the first connection portion 40 shows a downward trend.

[0062] In this setting method, when the transfer device grabs the micro light-emitting element 3 to be transferred and presses it down, the first site a of the first anchoring portion 20a and the first site a of the first anchoring portion 20b first come into contact with the first connection portion 40, breaking the first connection portion 40 in the area where it contacts the two first sites a, and the size of the residual structure at the edge of the micro light-emitting element 3 to be transferred can also be reduced.

[0063] Optionally, continuing to refer to Figure 3 and Figure 4 , in a possible embodiment, the first anchoring portion 20 can include a first sub-portion 201 and a second sub-portion 202; the first site a is located on the surface of the first sub-portion 201 facing the first connection portion 40, and the second site b is located on the surface of the second sub-portion 202 facing the first connection portion 40; in the direction perpendicular to the surface of the substrate 1, the height H1 of the first sub-portion 201 is greater than the height of the second sub-portion 202.

[0064] Specifically, as Figure 3 and Figure 4 shown, the first anchoring portion 20 can be composed of a first sub-portion 201 and a second sub-portion 202. The surface of the first sub-portion 201 facing the first connection portion 40 is the first sub-surface 21 in the above embodiment, and the surface of the second sub-portion 202 facing the first connection portion 40 is the second sub-surface 22 in the above embodiment. Figure 3In the illustrated embodiment, the first anchoring portion 20 includes a first site a, a second site b, and a third site c at the same time. At this time, the first anchoring portion 20 may further include a third branch 203, and the third site c is located on the surface of the third branch 203 facing the first connecting portion 40. Along the direction from the first micro-light-emitting element 31 to be transferred to the second micro-light-emitting element 32 to be transferred, the first branch 201, the second branch 202, and the third branch 203 are arranged in sequence. The actual setting method is not limited to this. When the structure of the first anchoring portion 20 is Figure 6 the structure shown, the first anchoring portion 20 may only include a first branch 201 and a second branch 202. The first branch 201 is located on the side of the second branch 202 close to any one of the micro-light-emitting elements 3 to be transferred. In the following embodiments, the first anchoring portion 20 including the first branch 201, the second branch 202, and the third branch 203 is taken as an example for introduction.

[0065] Furthermore, referring to Figure 3 and Figure 4 , the height H1 of the first branch 201 in the direction perpendicular to the substrate 1 and pointing to the tether structure 4 (i.e., the direction perpendicular to the surface of the substrate 1) can be set to be greater than the height H2 of the second branch 202 in this direction, so that the distance D1 between the first site a on the first branch 201 and the first connecting portion 40 is less than the distance D2 between the second site b on the second branch 202 and the first connecting portion 40. In this way, the surface of the first anchoring portion 20 facing the substrate 1 can be set as a flat surface, improving the fixing effect between the anchoring structure 2 and the substrate 1. Similarly, the height H3 of the third branch 203 in the direction perpendicular to the substrate 1 and pointing to the tether structure 4 can be set to be greater than the height H2 of the second branch 202 in this direction, so that the distance D3 between the third site c on the third branch 203 and the first connecting portion 40 is less than the distance D2 between the second site b on the second branch 202 and the first connecting portion 40.

[0066] Among them, for the specific setting method of the first branch 201 and the second branch 202, the embodiments of the present invention do not make limitations. Figure 3 and Figure 4 exemplarily show that the projection of the first branch 201 in the direction parallel to the surface of the substrate (i.e., the projection on the cross-section shown in Figure 3 and Figure 4 ) is trapezoidal, the projection of the second branch 202 in the direction parallel to the surface of the substrate is rectangular, and the first site a and the second site b are respectively located on the flat first sub-surface 21 and the second sub-surface 22. The actual situation is not limited to this.

[0067] Figure 7 This is a schematic structural diagram of a first anchoring portion provided by an embodiment of the present invention. Referring to Figure 7, in other alternative embodiments, on the side of the first sub - portion 201 and the second sub - portion 202 of the first anchoring portion 20 facing the first connecting portion 40 is a curved surface, and / or, the side wall where the first sub - portion 201 is connected to the second sub - portion 202 is a curved surface, but not limited thereto. Setting the side of the first anchoring portion 20 facing the first connecting portion 40 as a curved surface can make the connection between the first sub - portion 201 and the second sub - portion 202 smooth, avoid breakage between the first sub - portion 201 and the second sub - portion 202 before massive transfer, and improve the reliability of the anchoring structure 2.

[0068] The structure of the first anchoring portion 20 is not limited to the structure provided in the embodiments of the present application. Any structure that can meet the setting requirements of the first site a and the second site b is within the scope of the technical solutions protected by the embodiments of the present invention.

[0069] Optionally, continue to refer to Figure 3 and Figure 4 , in a possible embodiment, it can be set that along the direction from the first anchoring portion 20 to the first connecting portion 40, the area of the orthographic projection of the first sub - portion 201 of the first anchoring portion 20 on the plane where the substrate 1 is located gradually decreases.

[0070] Specifically, as Figure 3 and Figure 4 shown, it can be set that along the direction from the first anchoring portion 20 to the first connecting portion 40, the area of the orthographic projection of the first sub - portion 201 of the first anchoring portion 20 on the first connecting portion 40 gradually decreases. In other words, along the direction from the first anchoring portion 20 to the first connecting portion 40, the width of the first sub - portion 201 in the horizontal direction gradually decreases, so that the size of the first sub - surface 21 (or the third sub - surface 23) where the first site a (or the third site c) is located is smaller. The area of the force - bearing point of the first connecting portion 40 in the contact area with the first site a is smaller, and the first connecting portion 40 is more likely to break in this area.

[0071] Figure 8 is a schematic structural diagram of another first anchoring portion provided by the embodiments of the present invention. Figure 8 In the shown embodiment, along the direction from the substrate 1 to the tether structure 4, the projection of the part of the first sub - portion 201 (the third sub - portion 203) of the first anchoring portion 20 that is higher than the second sub - portion 202 in the direction parallel to the substrate surface is triangular. Or rather, the part of the first sub - portion 201 that is higher than the second sub - portion 202 is a conical - like sub - portion. The bottom edge of the conical - like sub - portion and the surface of the second sub - portion 202 (the third sub - portion 203) facing the first connecting portion 40 are in the same plane, and the vertex of the conical - like sub - portion faces the first connecting portion 40. In this setting, the first site a (or the third site c) is the vertex of the conical - like sub - portion, and the area of the force - bearing point of the first connecting portion 40 in the contact area with the first site a or the third site c is the smallest.

[0072] In other embodiments, it is also possible to set the projection of the first branch 201 in the direction parallel to the substrate surface to be rectangular, that is, along the direction from the first anchoring portion 20 to the first connecting portion 40, the area of the orthographic projection of the first branch 201 (the third branch) on the first connecting portion 40 remains unchanged, and the width of the first branch 201 (the third branch) in the horizontal direction remains unchanged. In this way, the structure of the first anchoring portion 20 is relatively regular and the manufacturing process is relatively simple.

[0073] Optionally, reference may continue to be made to Figure 3 and Figure 4 , in possible embodiments, it is possible to set the area of the orthographic projection of the first branch 201 on the plane where the substrate 1 is located to be smaller than the area of the orthographic projection of the second branch 202 on the plane where the substrate 1 is located.

[0074] Specifically, as Figure 3 and Figure 4 shown, it is possible to set the width L3 of the first branch 201 and the third branch in the horizontal direction to be smaller than the width L4 of the second branch 202 in the horizontal direction, so that the area of the first sub-surface 21 where the first site a is located and the area of the third sub-surface 23 where the third site c is located are relatively small, and the area of the second sub-surface 22 connecting the first sub-surface 21 and the third sub-surface 23 in the middle is relatively large, ensuring that the first site a and the third site c are closer to the micro light-emitting elements 3 to be transferred on both sides.

[0075] In addition, those skilled in the art can understand that the size of the first anchoring portion 20 is generally very small. In actual production, by setting the areas of the first sub-surface 21 and the third sub-surface 23 to be small, the first sub-surface 21 and the third sub-surface 23 can be approximately regarded as the first site a and the third site c. This makes the force-bearing area of the first connecting portion 40 in the region where it contacts the first anchoring portion 20 (the region where the first site a and the third site c are located) relatively small.

[0076] Among them, regarding the widths of the first branch 201 and the second branch 202 in the direction from the first micro light-emitting element 31 to the second micro light-emitting element 32 to be transferred, the embodiments of the present invention do not make any limitations, and those skilled in the art can set them according to actual needs.

[0077] Optionally, Figure 9 is a top-view structural schematic diagram of a micro light-emitting element array provided by an embodiment of the present invention, Figure 10 is Figure 9 a cross-sectional structural schematic diagram along the B-B' direction, reference may be made to Figure 9 and Figure 10, in a possible embodiment, the substrate 1 may include a first region I and a second region II, and the second region II at least partially surrounds the first region I; the first connection portion 40 includes a first sub-connection portion 41 and a second sub-connection portion 42, the first sub-connection portion 41 is located in the first region I, and the second sub-connection portion 42 is located in the second region II; the first anchoring portion 20 includes a first sub-anchoring portion 24 and a second sub-anchoring portion 25, the orthographic projection of the first sub-anchoring portion 24 on the substrate 1 is located within the orthographic projection of the first sub-connection portion 41 on the substrate 1, and the orthographic projection of the second sub-anchoring portion 25 on the substrate 1 is located within the orthographic projection of the second sub-connection portion 42 on the substrate 1; wherein, in the direction perpendicular to the surface of the substrate 1, the height difference between the first branch 201 and the second branch 202 of the first sub-anchoring portion 24 is greater than the height difference between the first branch 201 and the second branch 202 of the second sub-anchoring portion 25; and / or, the area of the orthographic projection of the first branch 201 of the first sub-anchoring portion 24 on the plane where the substrate 1 is located is smaller than the area of the orthographic projection of the first branch 201 of the second sub-anchoring portion 25 on the plane where the substrate 1 is located.

[0078] Specifically, as Figure 9 and Figure 10 shown, in the embodiment of the present application, the substrate 1 can be divided into a first region I and a second region II that at least partially surrounds the first region I. It can also be understood that the first region I is the central region of the substrate 1, and the second region II is at least part of the edge region of the substrate 1. Among them, the second region II can be further divided into a side region IIa and a corner region IIb. Figure 9 Only the anchoring structure 2, the micro light-emitting element 3 to be transferred, and the tether structure 4 are shown in

[0079] Since the first region I is the middle region of the substrate 1, a plurality of micro light-emitting elements 3 to be transferred are arranged in an array along the first direction X and the second direction Y in the first region I. Both the first direction X and the second direction Y are parallel to the extending direction of the plane where the substrate 1 is located, and the first direction X and the second direction Y intersect. For each micro light-emitting element 3 to be transferred in the first region I, first connection portions 40 are provided on both sides of the micro light-emitting element 3 to be transferred along the first direction X and on both sides along the second direction Y. That is, first connection portions 40 are respectively provided around each micro light-emitting element 3 to be transferred in the first region I. And the second region II is the edge region of the substrate 1. For the micro light-emitting element 3 to be transferred in the side region IIa, the first connection portion 40 does not need to be formed on the side of the micro light-emitting element 3 to be transferred close to the edge of the substrate 1; for the micro light-emitting element 3 to be transferred in the corner region IIb, the first connection portion 40 does not need to be formed on both sides of the micro light-emitting element 3 to be transferred close to the edge of the substrate 1. It can be seen that the number of first connection portions 40 connected to each micro light-emitting element 3 to be transferred in the first region I is greater than the number of first connection portions 40 connected to each micro light-emitting element 3 to be transferred in the second region II.

[0080] Furthermore, referring to Figure 9 andFigure 10 , the first connection part 40 located in the first area I can be defined as the first sub-connection part 41, and the first connection part 40 located in the second area II can be defined as the second sub-connection part 42. Two adjacent micro light-emitting elements 3 to be transferred in the second area II are connected through the second sub-connection part 42, two adjacent micro light-emitting elements 3 to be transferred in the first area I are connected through the first sub-connection part 41, and two mutually adjacent micro light-emitting elements 3 to be transferred in the first area I and the second area II are connected through the first sub-connection part 41. Among them, in the figure, the first connection part 40 with different filling patterns is used to divide the first sub-connection part 41 and the second sub-connection part 42. In fact, the first sub-connection part 41 and the second sub-connection part 42 should be made of the same material and prepared in the same process.

[0081] Correspondingly, as Figure 10 shown, the first anchoring part 20 corresponding to the first sub-connection part 41 can be defined as the first sub-anchoring part 24, and the first anchoring part 20 corresponding to the second sub-connection part 42 can be defined as the second sub-anchoring part 25. The orthographic projection of the first sub-connection part 41 on the substrate 1 covers the orthographic projection of the first sub-anchoring part 24 on the substrate 1, and the orthographic projection of the second sub-connection part 42 on the substrate 1 covers the orthographic projection of the second sub-anchoring part 25 on the substrate 1.

[0082] During mass transfer, in order to pick up an independent micro light-emitting element 3 to be transferred, it is necessary to cut off the first connection part 40 connected to all edges of the micro light-emitting element 3 to be transferred. Since the number of the first sub-connection parts 41 connected to the micro light-emitting elements 3 to be transferred in the first area I is large, and the number of the second sub-connection parts 42 connected to the micro light-emitting elements 3 to be transferred in the second area II is small, in order to ensure that the first sub-connection part 41 in the first area I and the second sub-connection part 42 in the second area II are broken simultaneously, the structures of the first sub-anchoring part 24 and the second sub-anchoring part 25 can be set differently, so that the stress applied by the first sub-anchoring part 24 to the first sub-connection part 41 is greater than the stress applied by the second sub-anchoring part 25 to the second sub-connection part 42.

[0083] Specifically, it can be set in the direction where the substrate 1 vertically points to the tethering structure 4. The height H4 of the part of the first branch 201 of the first sub-anchoring part 24 that is higher than the second branch 202 is greater than the height H5 of the part of the first branch 201 of the second sub-anchoring part 25 that is higher than the second branch 202; that is, the height difference H4 between the first branch 201 and the second branch 202 of the first sub-anchoring part 24 is greater than the height difference H5 between the first branch 201 and the second branch 202 of the second sub-anchoring part 25; or, it can be set that the width L5 of the first branch 201 of the first sub-anchoring part 24 in the horizontal direction is less than the width L6 of the first branch 201 of the second sub-anchoring part 25 in the horizontal direction, so that the contact area between the first point a of the first sub-anchoring part 24 and the first sub-connecting part 41 is less than the contact area between the first point a of the second sub-anchoring part 25 and the second sub-connecting part 42; or it can be set that the first sub-anchoring part 24 and the second sub-anchoring part 25 simultaneously satisfy the above two conditions, as Figure 10 shown.

[0084] In this setting method, during mass transfer, it can ensure that the first branch 201 of the first sub-anchoring part 24 generates a large stress on the first sub-connecting part 41, so that the first sub-connecting part 41 in the first area I and the second sub-connecting part 42 in the second area II are broken simultaneously, improving the picking success rate of the micro-light-emitting elements 3 to be transferred in different areas during mass transfer.

[0085] Among them, for the specific actual parameters of the first branch 201, the second branch 202 of the first sub-anchoring part 24, and the first branch 201 and the second branch 202 of the second sub-anchoring part 25, the embodiments of the present invention will not elaborate or limit, and can be set by those skilled in the art according to actual needs.

[0086] Optionally, continue to refer to Figure 3 , in the embodiments of the present application, along the direction perpendicular to the plane where the substrate 1 is located, the micro-light-emitting element 3 to be transferred includes a stacked electrode layer 34 and a functional layer 35, and the functional layer 35 is located on the side of the electrode layer 34 away from the substrate 1; a gap 9 is formed between two adjacent micro-light-emitting elements 3 to be transferred, the first anchoring part 20 of the anchoring structure 2 is located in the gap 9, and the extending direction of the first anchoring part 20 is perpendicular to the plane where the substrate 1 is located.

[0087] Specifically, as Figure 3As shown in the figure, the micro light-emitting element 3 to be transferred includes a stacked structure. Along the direction perpendicular to the substrate 1 and pointing to the tether structure 4, the micro light-emitting element 3 to be transferred includes an electrode layer 34 and a functional layer 35. The electrode layer 34 is located on the side close to the substrate 1, and the functional layer 35 is located on the side far from the substrate 1. Among them, the electrode layer 34 may include two electrodes, which are used to receive the pad connection of the substrate subsequently; the functional layer 35 may include multiple semiconductor material layers, such as an N-type semiconductor material layer and a P-type semiconductor material layer. For the specific setting method of each semiconductor material layer in the functional layer 35, the embodiments of the present invention will not be elaborated or limited. In this way, the micro light-emitting element 3 to be transferred has a certain thickness in the direction perpendicular to the surface of the substrate 1, and a certain depth of gap 9 will be formed between two adjacent micro light-emitting elements 3 to be transferred. The first anchoring portion 20 can extend from the surface of the substrate 1 in the vertical direction into the gap 9. Along the orientation shown in the figure, the first connecting portion 40 is located at the top of the gap 9. During mass transfer, when the micro light-emitting element 3 to be transferred is pressed down, the first anchoring portion 20 cuts off the first connecting portion 40.

[0088] Optionally, reference may continue to Figure 3 , in a possible embodiment, the anchoring structure 2 may further include a second anchoring portion 26, which is located between the substrate 1 and the plurality of first anchoring portions 20; the surface of the plurality of first anchoring portions 20 facing away from the first connecting portion 40 is integrally connected to the surface of the second anchoring portion 26 facing away from the substrate 1.

[0089] Specifically, as Figure 3 shown, the anchoring structure 2 may further include a second anchoring portion 26 located between the first anchoring portion 20 and the substrate 1, and the second anchoring portion 26 may be provided as a whole layer. One surface of the second anchoring portion 26 is attached to the surface of the substrate 1, and the surface of the second anchoring portion 26 facing away from the substrate 1 is connected to the surface of the first anchoring portion 20 facing away from the first connecting portion 40, so that the plurality of first anchoring portions 20 and the second anchoring portion 26 form an integral anchoring structure 2. The presence of the second anchoring portion 26 can enhance the bonding effect between the first anchoring portion 20 and the substrate 1, and avoid problems such as detachment between the first anchoring portion 20 and the substrate 1.

[0090] Of course, in other embodiments not shown, the anchoring structure 2 may be composed only of the first anchoring portion 20, and the surface of the first anchoring portion 20 facing away from the first connecting portion 40 is directly attached to the substrate 1, thereby simplifying the preparation process of the anchoring structure 2.

[0091] Optionally, reference may continue to Figure 3 , in the embodiments of the present application, the tether structure 4 may further include a second connecting portion 43, which is located on the side of the micro light-emitting element 3 to be transferred facing away from the anchoring structure 2, and the second connecting portion 43 is used to connect any two adjacent first connecting portions 40.

[0092] Specifically, as Figure 3As shown, the tether structure 4 may further include a second connecting portion 43 disposed on a side of the micro light-emitting element 3 to be transferred away from the anchoring structure 2. The second connecting portion 43 connects any two adjacent first connecting portions 40. The presence of the second connecting portion 43 can improve the fixing effect of the tether structure 4 on the micro light-emitting element 3 to be transferred, and further improve the reliability of the micro light-emitting element array.

[0093] Among them, as described in the above embodiments, in the preparation process of the micro light-emitting element array (as Figure 5 shown), a second inorganic layer 8 can be prepared at least on a side of the first inorganic layer 7 between adjacent micro light-emitting elements 3 to be transferred away from the anchoring structure 2 to form the first connecting portion 40. In this embodiment, in the preparation process of the micro light-emitting element array, a whole layer of the second inorganic layer 8 can be prepared on a side of the micro light-emitting element 3 to be transferred and the first inorganic layer 7 between adjacent micro light-emitting elements 3 to be transferred away from the anchoring structure 2, so as to simultaneously form the first connecting portion 40 and the second connecting portion 43 of an integral structure, thereby simplifying the preparation process of the tether structure 4.

[0094] Optionally, as mentioned in the above embodiments, a buffer layer 6 can be disposed on a side of the micro light-emitting element 3 to be transferred away from the substrate 1. When the buffer layer 6 exists, the second connecting portion 43 can be formed on a surface of the buffer layer 6 away from the micro light-emitting element 3 to be transferred.

[0095] Optionally, in other embodiments not shown, the tether structure 4 may be composed only of the first connecting portion 40, and the first connecting portion 40 is arranged to extend horizontally to a surface of an adjacent micro light-emitting element 3 to be transferred away from the anchoring structure 2, so as to improve the fixing effect of the tether structure 4 on the micro light-emitting element 3 to be transferred.

[0096] Optionally, Figure 11 is a partial cross-sectional structural schematic diagram of another micro light-emitting element array provided by an embodiment of the present invention. Refer to Figure 11 , in a possible embodiment, the micro light-emitting element array further includes a sacrificial layer 10, and the sacrificial layer 10 is filled between the anchoring structure 2 and the micro light-emitting element 3 to be transferred.

[0097] Specifically, as Figure 11 shown, a sacrificial layer 10 can also be provided in the micro light-emitting element array. The sacrificial layer 10 is filled between the anchoring structure 2 and the micro light-emitting element 3 to be transferred, so that the anchoring structure 2 and the micro light-emitting element 3 to be transferred do not contact. The sacrificial layer 10 can be used to protect the micro light-emitting element 3 to be transferred before mass transfer to avoid damage to the micro light-emitting element 3 to be transferred.

[0098] Before the massive transfer, the sacrificial layer 10 filled between the anchoring structure 2 and the micro-light-emitting element 3 to be transferred needs to be removed first, so that a gap is formed between the micro-light-emitting element 3 to be transferred and the anchoring structure 2, and the side of the micro-light-emitting element 3 to be transferred facing the substrate 1 is suspended. When the transfer device grabs and presses down the micro-light-emitting element 3 to be transferred, the existence of the gap provides a certain pressing space for the micro-light-emitting element 3 to be transferred, avoiding direct contact between the electrode layer 34 of the micro-light-emitting element 3 to be transferred and the anchoring structure 2 during pressing.

[0099] Among them, the sacrificial layer 10 can be formed before the preparation of the anchoring structure 2. For the preparation method of the sacrificial layer 10, this application will not elaborate or limit it.

[0100] Optionally, it is worth mentioning that in the embodiments of this application, the anchoring structure 2 is prepared using a metal material. The stress generated by the anchoring structure 2 prepared using a metal material on the first connecting portion 40 is more concentrated when contacting the first connecting portion 40, which is beneficial to breaking the first connecting portion 40 at the first site a.

[0101] Among them, the type of the metal material is not limited in this embodiment, and those skilled in the art can select according to actual needs. Exemplarily, the metal material can be a metal alloy material including metals such as chromium, nickel, and manganese, but is not limited thereto.

[0102] Based on the same inventive concept, the embodiments of the present invention also provide a method for transferring a micro-light-emitting element, which is used to transfer the micro-light-emitting element to be transferred in the micro-light-emitting element array provided by any embodiment of the present invention. Figure 12 It is a flowchart of a method for transferring a micro-light-emitting element provided by an embodiment of the present invention. With reference to Figure 3 、 Figure 4 and Figure 12 , the transfer method includes:

[0103] S110. Provide a micro-light-emitting element array.

[0104] Among them, the micro-light-emitting element array includes a substrate 1, an anchoring structure 2, a plurality of micro-light-emitting elements 3 to be transferred, and a tethering structure 4; the anchoring structure 2 is disposed between the substrate 1 and the tethering structure 4, and the tethering structure 4 connects the micro-light-emitting elements 3 to be transferred; the tethering structure 4 includes a first connecting portion 40, and the first connecting portion 40 is located between two adjacent micro-light-emitting elements 3 to be transferred and connects the two adjacent micro-light-emitting elements 3 to be transferred; the anchoring structure 2 includes a first anchoring portion 20, and the orthographic projection of the first anchoring portion 20 on the substrate 1 is located within the orthographic projection of the first connecting portion 40 on the substrate 1. One side surface of the first anchoring portion 20 facing the first connecting portion 40 includes a first site a and a second site b; in the direction perpendicular to the surface of the substrate 1, the distance between the first site a and the first connecting portion 40 is D1, and the distance between the second site b and the first connecting portion 40 is D2. The first site a is located on the side of the second site b closer to the micro-light-emitting element 3 to be transferred; among them, D1 < D2.

[0105] S120. Use a transfer device to grasp the micro-light-emitting element to be transferred and press it down, so that the first connecting portion breaks in the area where it contacts the first site of the first anchoring portion.

[0106] Specifically, the transfer device can be first moved above the micro-light-emitting element array, and then the transfer device is used to adsorb the micro-light-emitting element 3 to be transferred and press down the transfer device. Since the distance between the first site a and the first connecting portion 40 is closer, when the transfer device is used to grasp the micro-light-emitting element 3 to be transferred and press it down, the first site a of the first anchoring portion 20 will first contact the first connecting portion 40. When the first site a contacts the first connecting portion 40, the second site b does not contact the first connecting portion 40. The area of the first connecting portion 40 that contacts the first site a is more likely to be stressed and break. Since the first site a is closer to the edge of the micro-light-emitting element 3 to be transferred, the size of the structure remaining on the edge of the micro-light-emitting element 3 after the first connecting portion 40 breaks in the area where it contacts the first site a is smaller, thereby greatly reducing the influence of the remaining structure on the subsequent process, improving the yield of the subsequent process, and further improving the reliability of the display device.

[0107] Among them, the transfer device can be a transfer head including an elastic stamp or an electrostatic transfer head, etc., but not limited thereto. Any transfer device that can grasp the micro-light-emitting element 3 to be transferred is within the scope of the technical solution protected by the embodiments of the present invention.

[0108] S130. Pick up the micro-light-emitting element to be transferred and transfer the micro-light-emitting element to be transferred to the receiving substrate.

[0109] Further, the transfer device is used to pick up the independent micro-light-emitting element 3 to be transferred and transfer the micro-light-emitting element 3 to be transferred to the receiving substrate. The receiving substrate can be an array substrate, and pads are arranged on the surface of the array substrate. The pads are connected to the electrodes of the micro-light-emitting element 3 to be transferred. A driving array is arranged inside the array substrate, and the driving array is used to drive the micro-light-emitting element 3 to be transferred to emit light.

[0110] The specific structure of the receiving substrate can be set by those skilled in the art according to actual needs, and the embodiments of the present invention will not elaborate or limit this.

[0111] The transfer method of the micro-light-emitting element provided by the embodiments of the present invention includes all the technical features and corresponding beneficial effects of the micro-light-emitting element array provided by any embodiment of the present invention, and will not be elaborated here too much.

[0112] Optionally, reference can be continued to Figure 3 and Figure 4 , in a possible embodiment, two adjacent micro-light-emitting elements 3 to be transferred include a first micro-light-emitting element 31 to be transferred and a second micro-light-emitting element 32 to be transferred. The first site a is located on the side of the second site b close to the first micro-light-emitting element 31; the surface of the first anchoring portion 20 facing the first connecting portion 40 further includes a third site c; the third site c is located on the side of the second site b close to the second micro-light-emitting element 32; in the direction perpendicular to the surface of the substrate 1, the distance between the third site c and the first connecting portion 40 is D3; wherein, D3 < D2; using the transfer device to grab the micro-light-emitting element 3 to be transferred and press down, so that the first connecting portion 40 breaks in the area where it contacts the first site a of the first anchoring portion 20 may include: using the transfer device to grab the micro-light-emitting element 3 to be transferred and press down, so that the first connecting portion 40 breaks in the area where it contacts the first site a and the third site c of the first anchoring portion 20.

[0113] Specifically, in this embodiment, the distance D3 between the third site c and the first connecting portion 40 on the first anchoring portion 20 is less than the distance D2 between the second site b and the first connecting portion 40. Compared with the second site b, the third site c is closer to the first connecting portion 40. When the transfer device grabs the micro-light-emitting element 3 to be transferred and presses it down, the first site a and the third site c of the first anchoring portion 20 will first contact the first connecting portion 40. When the first site a and the third site c respectively contact the first connecting portion 40, the second site b does not contact the first connecting portion 40. The area of the first connecting portion 40 that contacts the first site a and the third site c is more likely to be stressed and broken. Since both the first site a and the third site c are close to the edge of the micro-light-emitting element 3 to be transferred, the sizes of the residual structures remaining on the edges of the first micro-light-emitting element 31 and the second micro-light-emitting element 32 after the first connecting portion 40 breaks in the area where it contacts the first site a and the third site c are both small, further avoiding the adverse effects of the residual structures on the edges of each micro-light-emitting element 3 to be transferred on the subsequent manufacturing process.

[0114] Optionally, continue to refer to Figure 3 and Figure 4 , in a possible embodiment, the first anchoring portion 20 includes a first sub-portion 201 and a second sub-portion 202; the first site a is located on the surface of the first sub-portion 201 facing the first connecting portion 40, and the second site b is located on the surface of the second sub-portion 202 facing the first connecting portion 40; in the direction perpendicular to the surface of the substrate 1, the height H1 of the first sub-portion 201 is greater than the height H2 of the second sub-portion 202; using the transfer device to grab the micro-light-emitting element 3 to be transferred and pressing it down so that the first connecting portion 40 breaks in the area where it contacts the first site a of the first anchoring portion 20 includes: using the transfer device to grab the micro-light-emitting element 3 to be transferred and pressing it down so that the first connecting portion 40 breaks in the area where it contacts the first site a of the first anchoring portion 20; after the first connecting portion 40 breaks, the remaining part of the first connecting portion 40 at the edge of the micro-light-emitting element 3 to be transferred has a first pattern, and the first pattern is consistent with the pattern of at least part of the edge of the first sub-portion 201.

[0115] Specifically, in this embodiment, the first site a is located on the surface of the first sub-portion 201 facing the first connecting portion 40. When the first connecting portion 40 breaks in the area where it contacts the first site a, the break of the remaining part of the first connecting portion 40 at the edge of the micro-light-emitting element 3 to be transferred has a first pattern, and the first pattern should be the same as the edge pattern of the first sub-portion 201 that separates it.

[0116] Optionally, continue to refer to Figure 11, in a possible embodiment, the micro light-emitting element array further includes a sacrificial layer 10, and the sacrificial layer 10 is filled between the anchoring structure 2 and the micro light-emitting element 3 to be transferred; before using the transfer device to grasp the micro light-emitting element 3 to be transferred and press down, so that the first connecting portion 40 breaks at the region in contact with the first anchoring portion 20 at the first position a, it further includes: removing the sacrificial layer 10 to form a gap in at least a partial region between the anchoring structure 2 and the micro light-emitting element 3 to be transferred.

[0117] Specifically, a sacrificial layer 10 may also be provided in the micro light-emitting element array, and the sacrificial layer 10 is filled between the anchoring structure 2 and the micro light-emitting element 3 to be transferred, so that the anchoring structure 2 and the micro light-emitting element 3 to be transferred do not contact. The sacrificial layer 10 can be used to protect the micro light-emitting element 3 to be transferred before mass transfer, avoiding damage to the micro light-emitting element 3 to be transferred. Among them, before mass transfer, it is necessary to first remove the sacrificial layer 10 filled between the anchoring structure 2 and the micro light-emitting element 3 to be transferred, so that a gap is formed between the micro light-emitting element 3 to be transferred and the anchoring structure 2, and the side of the micro light-emitting element 3 facing the substrate 1 is suspended. When using the transfer device to grasp the micro light-emitting element 3 to be transferred and press down, the existence of the gap provides a certain pressing space for the micro light-emitting element 3 to be transferred, avoiding the electrode layer 34 of the micro light-emitting element 3 to be transferred from directly contacting the anchoring structure 2 when pressing down.

[0118] The transfer method provided by the embodiments of the present invention may further include any processes known to those skilled in the art, and the present application does not elaborate or limit this.

[0119] The embodiments of the present invention also provide a display device. Figure 13 It is a schematic structural diagram of a display device provided by the embodiments of the present invention. Figure 13 The shown display device is prepared by using the transfer method of the micro light-emitting element provided by any embodiment of the present invention. It can be understood that the display device provided by the embodiments of the present invention includes the transferred micro light-emitting elements, which have the corresponding beneficial effects of the micro light-emitting element array provided by the embodiments of the present invention, and will not be elaborated here. Exemplarily, the display device may be an electronic device such as a mobile phone, a computer, a smart wearable device (for example, a smart watch), and an in-vehicle display device, and the embodiments of the present invention do not limit this.

[0120] Note that the above is only the preferred embodiment of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, re-adjustments, combinations with each other, and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments only. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A micro-light-emitting element array, characterized in that, Comprising: a substrate, an anchoring structure, a plurality of micro light-emitting elements to be transferred, and a tethering structure; The anchoring structure is disposed between the substrate and the tethering structure, and the tethering structure connects the micro light-emitting elements to be transferred; The tethering structure includes a first connecting portion, and the first connecting portion is located between two adjacent micro light-emitting elements to be transferred and connects the two adjacent micro light-emitting elements to be transferred; The anchoring structure includes a first anchoring portion, and the orthographic projection of the first anchoring portion on the substrate is located within the orthographic projection of the first connecting portion on the substrate. One surface of the first anchoring portion facing the first connecting portion includes a first site and a second site; in a direction perpendicular to the surface of the substrate, the distance between the first site and the first connecting portion is D1, the distance between the second site and the first connecting portion is D2, and the first site is located on the side of the second site closer to the micro light-emitting element to be transferred; wherein, D1 < D2.

2. The micro-light-emitting element array according to claim 1, characterized in that, Two adjacent micro light-emitting elements to be transferred include a first micro light-emitting element to be transferred and a second micro light-emitting element to be transferred, and the first site is located on the side of the second site closer to the first micro light-emitting element to be transferred; One surface of the first anchoring portion facing the first connecting portion further includes a third site; the third site is located on the side of the second site closer to the second micro light-emitting element to be transferred; in a direction perpendicular to the surface of the substrate, the distance between the third site and the first connecting portion is D3; wherein, D3 < D2.

3. The micro-light-emitting element array according to claim 2, wherein, D1 = D3.

4. The micro-light emitting element array according to claim 2, characterized in that, In a direction parallel to the surface of the substrate, the distance between the first site and the second site is equal to the distance between the third site and the second site.

5. The micro-light emitting element array according to claim 1, wherein The first anchoring portion includes a first branch and a second branch; the first site is located on one surface of the first branch facing the first connecting portion, and the second site is located on one surface of the second branch facing the first connecting portion; In a direction perpendicular to the surface of the substrate, the height of the first branch is greater than the height of the second branch.

6. The micro-light-emitting element array according to claim 5, wherein, In the direction from the first anchoring portion towards the first connecting portion, the area of the orthographic projection of the first branch on the plane of the substrate gradually decreases.

7. The micro-light-emitting element array according to claim 6, wherein, The area of the orthographic projection of the first branch on the plane of the substrate is smaller than the area of the orthographic projection of the second branch on the plane of the substrate.

8. The micro-light-emitting element array according to claim 5, wherein The substrate includes a first region and a second region, and the second region at least partially surrounds the first region; the first connecting portion includes a first sub-connecting portion and a second sub-connecting portion, the first sub-connecting portion is located in the first region, and the second sub-connecting portion is located in the second region; The first anchoring portion includes a first sub-anchoring portion and a second sub-anchoring portion, the orthographic projection of the first sub-anchoring portion on the substrate is located within the orthographic projection of the first sub-connecting portion on the substrate, and the orthographic projection of the second sub-anchoring portion on the substrate is located within the orthographic projection of the second sub-connecting portion on the substrate; Wherein, in a direction perpendicular to the surface of the substrate, the height difference between the first part and the second part of the first sub-anchoring part is greater than the height difference between the first part and the second part of the second sub-anchoring part; and / or, the area of the projection of the first part of the first sub-anchoring part on the plane of the substrate is smaller than the area of the projection of the first part of the second sub-anchoring part on the plane of the substrate.

9. The micro light-emitting element array according to claim 1, wherein Along a direction perpendicular to the plane of the substrate, the micro-light-emitting element to be transferred includes a stacked electrode layer and a functional layer, and the functional layer is located on a side of the electrode layer away from the substrate. A gap is formed between two adjacent micro-light-emitting elements to be transferred, the first anchoring part of the anchoring structure is located in the gap, and the extending direction of the first anchoring part is perpendicular to the plane of the substrate.

10. The micro-light-emitting element array according to claim 9, wherein The anchoring structure further includes a second anchoring part, and the second anchoring part is located between the substrate and the plurality of first anchoring parts; one side surface of the plurality of first anchoring parts facing away from the first connecting part is integrally connected to one side surface of the second anchoring part facing away from the substrate.

11. The micro-light-emitting element array according to claim 1, characterized in that, The tethering structure further includes a second connecting part, which is located on a side of the light-emitting element away from the anchoring structure, and the second connecting part is used to connect any two adjacent first connecting parts.

12. The micro-light emitting element array according to claim 1, wherein A sacrificial layer is further included, and the sacrificial layer is filled between the anchoring structure and the micro-light-emitting element to be transferred.

13. The micro-light-emitting element array according to claim 12, wherein The anchoring structure is prepared from a metal material.

14. A method for transferring a micro-light-emitting element, characterized in that, Comprising: Providing a micro-light-emitting element array; The micro-light-emitting element array includes a substrate, an anchoring structure, a plurality of micro-light-emitting elements to be transferred, and a tethering structure; The anchoring structure is arranged between the substrate and the tethering structure, and the tethering structure connects the micro-light-emitting elements to be transferred; the tethering structure includes a first connecting part, and the first connecting part is located between two adjacent micro-light-emitting elements to be transferred and connects the two adjacent micro-light-emitting elements; the anchoring structure includes a first anchoring part, and the projection of the first anchoring part on the substrate is located within the projection of the first connecting part on the substrate. One side surface of the first anchoring part facing the first connecting part includes a first site and a second site; in a direction perpendicular to the surface of the substrate, the distance between the first site and the first connecting part is D1, and the distance between the second site and the first connecting part is D2. The first site is located on a side of the second site close to the micro-light-emitting element to be transferred; wherein, D1 < D2; Using a transfer device to grasp the micro-light-emitting element to be transferred and press it down, so that the first connecting part breaks in the area in contact with the first site of the first anchoring part; Picking up the micro-light-emitting element to be transferred and transferring the micro-light-emitting element to be transferred to a receiving substrate.

15. The transfer method of the micro light-emitting element according to claim 14, characterized in that, Two adjacent micro light-emitting elements to be transferred include a first micro light-emitting element to be transferred and a second micro light-emitting element to be transferred. The first site is located on the side of the second site close to the first micro light-emitting element to be transferred; the surface of the first anchoring portion facing the first connecting portion further includes a third site; the third site is located on the side of the second site close to the second micro light-emitting element to be transferred; in the direction perpendicular to the surface of the substrate, the distance between the third site and the first connecting portion is D3; where D3 < D2. Using a transfer device to grasp the micro light-emitting element to be transferred and pressing it down, so that the first connecting portion breaks in the area where it contacts the first site of the first anchoring portion, including: Using a transfer device to grasp the micro light-emitting element to be transferred and pressing it down, so that the first connecting portion breaks in the area where it contacts the first site and the third site of the first anchoring portion.

16. The transfer method of the micro light-emitting element according to claim 14, wherein The first anchoring portion includes a first branch and a second branch; the first site is located on the surface of the first branch facing the first connecting portion, and the second site is located on the surface of the second branch facing the first connecting portion; in the direction perpendicular to the surface of the substrate, the height of the first branch is greater than the height of the second branch; Using a transfer device to grasp the micro light-emitting element to be transferred and pressing it down, so that the first connecting portion breaks in the area where it contacts the first site of the first anchoring portion, including: Using a transfer device to grasp the micro light-emitting element to be transferred and pressing it down, so that the first connecting portion breaks in the area where it contacts the first site of the first anchoring portion; after the first connecting portion breaks, the remaining part of the first connecting portion at the edge of the micro light-emitting element to be transferred has a first pattern, and the first pattern is consistent with the pattern of at least part of the edge of the first branch.

17. The transfer method of the micro-light emitting element according to claim 14, characterized in that, The micro light-emitting element array further includes a sacrificial layer, and the sacrificial layer is filled between the anchoring structure and the micro light-emitting element to be transferred; Before using a transfer device to grasp the micro light-emitting element to be transferred and pressing it down, so that the first connecting portion breaks in the area where it contacts the first site of the first anchoring portion, further including: Removing the sacrificial layer to form a gap in at least part of the area between the anchoring structure and the micro light-emitting element to be transferred.

18. A display device, characterized in that, Prepared by using the transfer method of the micro light-emitting element according to any one of claims 14 to 17 above.

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