Micro device substrate

Abstract

The present disclosure relates to a micro-device substrate, and relates to the technical field of display, comprising a substrate and a first adhesive layer located on one side of the substrate, the first adhesive layer comprises a plurality of chip transfer regions and a micro-particle region located between the plurality of chip transfer regions in a direction parallel to the plane on which the substrate lies, and the micro-particle region comprises at least two types of micro-particles with different diameters, so that the contact area between ectopic light-emitting elements and the first adhesive layer can be reduced, thereby reducing the adhesion, facilitating the removal of ectopic light-emitting elements in the later process, and improving the recycling rate of the micro-device substrate.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of display, and in particular, to a micro device substrate. BACKGROUND

[0002] At present, display panels are widely used in electronic devices such as mobile phones, tablet computers, smart wearable devices, etc. A common display panel includes light emitting elements and a driving circuit coupled with the light emitting elements. The driving circuit drives the light emitting elements to emit light. The light emitting elements include red light emitting elements, green light emitting elements and blue light emitting elements.

[0003] In the preparation process of the existing display panel, the process of transferring the light emitting elements to the circuit substrate will inevitably cause the light emitting elements to be offset. These offset light emitting elements are as sticky as normal light emitting elements on the receiving glue and are not easy to remove, which affects the transfer efficiency. SUMMARY

[0004] To solve the above technical problems, the present disclosure provides a micro device substrate which can reduce the adhesion between the offset light emitting elements and the receiving glue, is easy to remove, reduces the repair difficulty and improves the transfer efficiency.

[0005] The present disclosure provides a micro device substrate, comprising: a substrate and a first glue layer arranged on one side of the substrate;

[0006] In a direction parallel to the plane where the substrate is located, the first glue layer comprises a plurality of chip transfer zones and a micro particle zone between the chip transfer zones. The light emitting elements are located in the chip transfer zones, and the light emitting elements are bonded to the first glue layer.

[0007] The micro particle zone comprises micro particles, and the micro particles are located on the side of the first glue layer away from the substrate.

[0008] The technical scheme provided by the embodiments of the present disclosure has the following advantages compared with the prior art: by arranging the micro particle zone outside the chip transfer zone, when the transferred light emitting elements are excessively offset or deflected, the light emitting elements will overlap with the micro particle zone in a direction perpendicular to the first glue layer. The spacing of the micro particles can reduce the contact area between the light emitting elements and the first glue layer, facilitate the removal by water washing, reduce the repair difficulty of the micro device substrate, and improve the recycling rate of the micro device substrate and the transfer efficiency of the light emitting elements. BRIEF DESCRIPTION OF DRAWINGS

[0009] The accompanying drawings, which are incorporated into and form part of the specification, illustrate embodiments consistent with the present disclosure and, together with the specification, serve to explain the principles of the present disclosure.

[0010] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, for those skilled in the art, other drawings can also be obtained based on these drawings without any creative effort.

[0011] Figure 1 A top view of the micro device substrate described in the embodiments of the present disclosure;

[0012] Figure 2 A top view of the micro device substrate described in the embodiments of the present disclosure; Figure 1 A sectional view along the A-A' section;

[0013] Figure 3 A structure schematic diagram of the light emitting element provided in the embodiments of the present disclosure;

[0014] Figure 4 A structure schematic diagram of the light emitting element provided in the embodiments of the present disclosure; Figure 1 A relative position relationship diagram of the light emitting element and the micro particle area along the A-A' section;

[0015] Figure 5 A schematic diagram of the relationship between the diameter of the light emitting substrate groove of the light emitting element described in the embodiments of the present disclosure and the size of the micro particle diameter;

[0016] Figure 6 A schematic diagram of the relationship between the width of the transfer precision area corresponding to different light emitting elements described in the embodiments of the present disclosure;

[0017] Figure 7 A schematic diagram of the difference in the size of the micro particle around the light emitting element described in the embodiments of the present disclosure;

[0018] Figure 8 A process schematic diagram of transferring the light emitting element from the source substrate to the temporary substrate described in the embodiments of the present disclosure;

[0019] Figure 9 A process schematic diagram of transferring the light emitting element from the temporary substrate to the temporary substrate described in the embodiments of the present disclosure;

[0020] Figure 10 A process schematic diagram of transferring the light emitting element from the temporary substrate to the array substrate described in the embodiments of the present disclosure. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to more clearly understand the above-mentioned purposes, features and advantages of the present disclosure, the solutions of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0022] Many specific details are set forth in the following description in order to provide a thorough understanding of the present disclosure. However, the present disclosure can be practiced according to other embodiments that do not require some of the specific details described below. Obviously, the described embodiments are only some embodiments of the present disclosure and are not all embodiments.

[0023] In the production process of a display device comprising light emitting elements (for example, Micro LED), it is necessary to transfer the light emitting elements to the circuit substrate by mass transfer and bind them to the circuit substrate. Before that, the light emitting elements need to be transferred to an intermediate substrate. The micro device substrate mentioned in the present disclosure can be regarded as an intermediate substrate carrying a plurality of light emitting elements. The side of the light emitting elements without electrode pins is fixed to the micro device substrate by the first adhesive layer. Through the micro device substrate, the light emitting elements on it can be transferred to the corresponding circuit substrate, so that the electrode pins of the light emitting elements are bound to the circuit substrate. After the light emitting elements are transferred to the intermediate substrate, the light emitting elements may appear position deviation and form defective light emitting elements. The defective light emitting elements and normal light emitting elements are pasted on the intermediate substrate. It is difficult to remove the defective light emitting elements by simple water washing. If laser is used to remove them, the adhesive layer on the intermediate substrate may be damaged and cannot be repaired in situ. Therefore, the present disclosure provides a micro device substrate to solve the above technical problems.

[0024] Figure 1 A top view of the micro device substrate described in the embodiments of the present disclosure, Figure 2 For Figure 1 A sectional view along the A-A' section, please refer to Figure 1 And Figure 2 The micro device substrate 100 provided by the present disclosure comprises a substrate 10 and a first adhesive layer 20 arranged on one side of the substrate 10.

[0025] In the direction parallel to the plane where the substrate 10 is located, the first adhesive layer 20 comprises a plurality of chip transfer areas 30 and micro particle areas 60 between the chip transfer areas 30. The light emitting elements 40 are located in the chip transfer areas 30, and the light emitting elements 40 are bonded to the first adhesive layer 20.

[0026] The micro particle area 60 comprises micro particles 70, and the micro particles 70 are located on the side of the first adhesive layer 20 away from the substrate 10.

[0027] It should be noted that Figure 1 Only a top view of the micro device substrate is shown, and the actual shape of the micro device substrate is not limited. In some other embodiments of the present disclosure, the micro device substrate can also have shapes other than rectangles, such as circles, etc. In addition, Figure 1The micro device substrate 100 in the present disclosure is only schematically shown with light emitting elements on the micro device substrate, and the number and shape of the light emitting elements actually contained on the micro device substrate are not limited. The present disclosure only shows a scheme in which the light emitting elements include red light emitting elements, green light emitting elements and blue light emitting elements, but is not limited thereto. In some other embodiments of the present disclosure, the light emitting elements can also be provided in other colors as needed, or in addition to the red, green and blue light emitting elements, other color light emitting elements can also be included. Of course, the arrangement of the light emitting elements on the micro device substrate is also only schematic, and can also be provided in other arrangements as needed.

[0028] Specifically, referring to Figure 1 and Figure 2 , the micro device substrate 100 mentioned in the present disclosure includes a substrate 10 and a first adhesive layer 20, the first adhesive layer 20 is located on one side of the surface of the substrate 10, and the light emitting elements 40 are fixed on the micro device substrate 100 through the first adhesive layer 20. In the direction parallel to the plane where the substrate 10 is located, the first adhesive layer 20 includes a plurality of chip transfer regions 30, which are optionally arranged in an array on the plane where the first adhesive layer 20 is located. Among them, the light emitting elements 40 are located in the chip transfer regions 30, and the light emitting elements 40 are bonded to the first adhesive layer 20 in the chip transfer regions 30.

[0029] The first adhesive layer 20 also includes a micro particle region 60, which is located between the plurality of chip transfer regions 30. The regions of the first adhesive layer 20 other than the chip transfer regions 30 can be regarded as the micro particle region 60. Optionally, each chip transfer region 30 is surrounded by the micro particle region 60. The micro particle region 60 includes micro particles 70, which are located on the side of the first adhesive layer 20 away from the substrate 10, and at least part of the surface of the micro particles 70 protrudes from the first adhesive layer 20. In this way, by providing a plurality of chip transfer regions 30 and micro particle regions 60 between the plurality of chip transfer regions 30 on the first adhesive layer 20 in the micro device substrate 100, if the light emitting elements 40 are dislocated (for example, tilted and offset) during the transfer of the light emitting elements 40 using the micro device substrate 100 of the present disclosure, the tilted surface of the part of the light emitting elements 40 will be able to contact the micro particles 70 in the micro particle region 60 that protrude from the surface of the first adhesive layer 20, rather than directly contacting the first adhesive layer 20, thereby reducing the contact area between the light emitting elements that are tilted and offset and the first adhesive layer 20, reducing the adhesion of the dislocated light emitting elements, facilitating the removal of the dislocated light emitting elements in the later process, and facilitating the reduction of the repair difficulty of the micro device substrate, improving the recycling rate of the micro device substrate, and facilitating the improvement of the transfer efficiency of the light emitting elements, thereby facilitating the improvement of the production efficiency.

[0030] Please continue to refer to Figures 1 to 2In an optional embodiment provided by the present disclosure, the micro-particle region 60 in the micro-device substrate 100 includes micro-particles 70 of at least two different particle sizes.

[0031] Specifically, the micro-device substrate 100 includes a substrate 10 and a first adhesive layer 20 located on one side of the substrate 10. In the direction of the plane on which the substrate 10 is located, the first adhesive layer 20 includes a plurality of chip transfer regions 30, and the first adhesive layer 20 further includes a micro-particle region 60 located between the plurality of chip transfer regions 30, and each chip transfer region 30 is surrounded by the micro-particle region 60. The micro-particles 70 in the micro-particle region 60 include at least two different particle sizes. For example, the micro-particles 70 can include two different particle sizes, the micro-particles 70 can include three different particle sizes, the micro-particles 70 can include four different particle sizes, and so on. Here, it is not necessary to list all the different particle sizes, as long as the micro-particles 70 include at least two different particle sizes. In this way, the micro-particle region 60 on the side of the first adhesive layer 20 away from the substrate 10 includes at least two different particle sizes, so that the micro-particles 70 of different particle sizes protrude from the surface of the first adhesive layer 20 to different heights. When the tilted and offset light emitting element is at least partially located outside the chip transfer region 30, compared with the micro-particles 70 of the same size, the micro-particles 70 of different particle sizes protruding from the surface of the first adhesive layer 20 exhibit a height difference, which can further reduce the contact area between the first adhesive layer 20 and the tilted and offset light emitting element, and facilitate the removal of the tilted and offset light emitting element in subsequent processes.

[0032] Figure 3 A structural schematic diagram of the light emitting element provided in the embodiments of the present disclosure, Figure 4 A structural schematic diagram of the light emitting element provided in the embodiments of the present disclosure, Figure 1 A structural schematic diagram of the light emitting element provided in the embodiments of the present disclosure, Figures 1 to 4 In an optional embodiment provided by the present disclosure, the light emitting element 40 includes a light emitting substrate 44 and an electrode 45. The light emitting substrate 44 is located between the electrode 45 and the first adhesive layer 20. The surface of the light emitting substrate 44 of at least part of the light emitting element 40 facing the first adhesive layer 20 includes a patterned microstructure.

[0033] Optionally, the light emitting element 40 further comprises an N-type layer 411, a light emitting layer 412 and a P-type layer 413 between the light emitting substrate 44 and the electrode 45, wherein the N-type layer 411 is configured to provide electrons, the P-type layer 413 is configured to provide holes, the light emitting layer 412 is a core region for generating light by recombination of the electrons and the holes, when a forward voltage is applied to the N-type layer 411 and the P-type layer 413, the electrons and the holes are injected from the N-type layer 411 and the P-type layer 413 to the light emitting layer 412 respectively, the electrons and the holes meet and recombine in the light emitting layer 412, and energy is released in the process of recombination, which is in the form of photons, thereby generating light; the light emitting layer 412 is usually composed of a quantum well structure, and the energy band structure of the quantum well can effectively limit the movement of the electrons and the holes, improve the recombination efficiency, and further enhance the light emitting effect.

[0034] Specifically, in the conventional art, it is usually necessary to form the light emitting element 40 on a special material substrate, for example, epitaxially growing the light emitting element on a sapphire substrate, the light emitting element 40 comprises the light emitting substrate 44 and the N-type layer 411, the light emitting layer 412 and the P-type layer 413 grown on the light emitting substrate 44 and the electrode 45, and after the growth of the light emitting element 40 is completed, the light emitting element 40 is transferred to the chip transfer area 30 on the micro device substrate 100 after being peeled off from the sapphire substrate, at this time, the light emitting substrate 44 in the light emitting element 40 is located between the electrode 45 and the first adhesive layer 20 on the micro device substrate 100, that is, when the light emitting element 40 is transferred to the micro device substrate 100, the electrode 45 in the light emitting element 40 is located on the side of the first adhesive layer 20 away from the substrate 10, and the light emitting substrate 44 in the light emitting element 40 is located on the side of the electrode 45 facing the first adhesive layer 20 and is bonded to the first adhesive layer 20, when the surface of the sapphire substrate has a microstructure, the light emitting substrate 44 of the light emitting element 40 grown on the sapphire substrate also has a corresponding patterned microstructure, so that the surface of at least part of the light emitting substrate 44 of the light emitting element 40 facing the first adhesive layer 20 comprises a patterned microstructure; in this way, when the surface of at least part of the light emitting substrate 44 of the light emitting element 40 facing the first adhesive layer 20 comprises a patterned microstructure, the contact area between at least part of the ectopic light emitting element 90 located in the micro-particle area 60 and the micro-particle 70 is smaller, so that the adhesion between the ectopic light emitting element 90 and the first adhesive layer 20 is smaller, which is convenient for removal in subsequent processes.

[0035] It should be noted that the "ectopic light emitting element 90" refers to the light emitting element 40 transferred to the micro device substrate 100 and at least partially located outside the chip transfer area 30, which corresponds to the light emitting element described above that is tilted and offset or has a changed position, for example, a same ectopic light emitting element 90 partially located in the chip transfer area 30 and partially located in the micro-particle area 60, or a same ectopic light emitting element 90 entirely located in the micro-particle area 60.

[0036] Figure 5 The schematic diagram of the relationship between the diameter of the luminescent substrate recess 46 of the luminescent element and the diameter of the micro-particle is shown in FIG. 4. Figures 1 to 5 In an optional embodiment provided by the present disclosure, the patterned microstructure includes the arrayed recesses 46, and the minimum particle size D1 of the micro-particles 70 is greater than the maximum diameter d of the recesses 46 in the patterned microstructure.

[0037] Specifically, the luminescent element growth substrate in the prior art usually includes the arrayed protrusions, and when the luminescent element 40 is epitaxially grown on the luminescent element growth substrate, the luminescent substrate 44 of the luminescent element 40 peeled off from the luminescent element growth substrate usually has the arrayed recesses 46 corresponding to the protrusions, and thus the patterned microstructure in the luminescent substrate 44 includes the arrayed recesses 46, and the maximum diameter of the recesses 46 is d; as described above, the micro-particle region 60 includes at least two kinds of micro-particles 70 with different particle sizes, wherein the maximum diameter of the micro-particles 70 is D2, the minimum particle size of the micro-particles 70 is D1, and the relationship between the diameter of the micro-particles 70 and the maximum diameter of the recesses 46 is D2>D1>d, that is, the maximum diameter d of the recesses 46 in the patterned microstructure of the luminescent substrate 44 is less than the minimum particle size D1 of the micro-particles 70, and thus when the luminescent element 40 is transferred to the micro-device substrate 100, the luminescent substrate 44 of the misaligned luminescent element 90 at least partially contacts the micro-particles 70 in the micro-particle region 60, and the maximum diameter d of the recesses 46 in the patterned microstructure of the luminescent substrate 44 is less than the minimum particle size D1 of the micro-particles 70, which can prevent the micro-particles 70 in the micro-particle region 60 from being clamped with the patterned microstructure luminescent substrate 44 of the misaligned luminescent element 90, reduce the difficulty of removing the misaligned luminescent element 90 in the subsequent process, and improve the recycling rate of the micro-device substrate 100.

[0038] Please continue to refer to Figures 1 to 5 In an optional embodiment provided by the present disclosure, the surface of the micro-particle 70 is smooth and non-adhesive.

[0039] Specifically, the micro-particle 70 can be made by a spray printing process, the surface of the micro-particle 70 is smooth and non-adhesive, and the part of the surface of the micro-particle 70 protruding from the first adhesive layer 20 is smooth and non-adhesive, and the luminescent substrate 44 of the misaligned luminescent element 90 at least partially located in the micro-particle region 60 contacts the micro-particle 70 with a smooth and non-adhesive surface, which can further reduce the bonding strength between the misaligned luminescent element 90 and the micro-particle region 60, facilitate the removal of the misaligned luminescent element 90 in the subsequent process, and improve the recycling rate of the micro-device substrate 100.

[0040] In an optional embodiment provided in the present disclosure, the micro-particles 70 are arc-shaped surfaces, preferably, the micro-particles 70 are spherical; when the ectopic light-emitting element 90 is at least partially located in the micro-particle region 60, the arc-shaped surface of the micro-particle 70 can reduce the risk of the light-emitting element 40 being broken by impact, in addition, the arc-shaped surface of the micro-particle 70 can further reduce the contact area with the light-emitting element 40, thus, the arc-shaped surface of the micro-particle 70 can reduce the probability of the light-emitting element 40 being broken by impact while reducing the contact area with the light-emitting element 40.

[0041] Please continue to refer to Figures 1 to 5 In an optional embodiment provided in the present disclosure, the height of the micro-particle 70 protruding from the first adhesive layer 20 in the direction perpendicular to the plane where the substrate 10 is located is less than or equal to 3 μm.

[0042] Specifically, in the direction parallel to the plane where the first adhesive layer 20 is located, the micro-particle region 60 is located between the plurality of chip transfer regions 30, the micro-particle region 60 includes at least two types of micro-particles 70 with different particle sizes, the micro-particles 70 are located on the side of the first adhesive layer 20 away from the substrate 10, the micro-particles 70 are at least partially embedded in the first adhesive layer 20, that is, the micro-particles 70 are at least partially protruding from the surface of the first adhesive layer 20, the height of the micro-particles 70 protruding from the surface of the first adhesive layer 20 in the direction perpendicular to the plane where the first adhesive layer 20 is located is greater than 0, less than or equal to 3 μm, optionally, the height of the micro-particles 70 protruding from the surface of the first adhesive layer 20 is less than or equal to 1.5 μm; optionally, the height of the micro-particles 70 protruding from the surface of the first adhesive layer 20 is less than or equal to 2 μm; optionally, the height of the micro-particles 70 protruding from the surface of the first adhesive layer 20 is less than or equal to 2.5 μm; and so on, which are not listed one by one here, as long as the height of the micro-particles 70 protruding from the first adhesive layer 20 in the direction perpendicular to the plane where the first adhesive layer 20 is located is less than or equal to 3 μm; if the height of the micro-particles 70 protruding from the first adhesive layer 20 is greater than 3 μm, the height difference between the light-emitting element 40 located in the chip transfer region 30 and the micro-particles 70 in the micro-particle region 60 in the direction perpendicular to the plane where the substrate 10 is located is small, which is not conducive to the secondary transfer of the light-emitting element 40 when the micro-device substrate 100 is used as a transfer substrate, thus, when the height of the micro-particles 70 protruding from the first adhesive layer 20 is less than or equal to 3 μm, the micro-particles 70 protruding from the first adhesive layer 20 reduce the adhesion between the ectopic light-emitting element 90 and the first adhesive layer 20, the height of the micro-particles 70 protruding from the first adhesive layer 20 is less than the height of the light-emitting element 40, which is conducive to the secondary transfer of the light-emitting element 40 and reduces the difficulty of transfer.

[0043] In an optional embodiment provided in the present disclosure, the micro-particles 70 include one or more of organic particles, inorganic particles, and metal particles.

[0044] Specifically, the micro-particles 70 can be one or more of organic particles (polytetrafluoroethylene, etc.), inorganic particles (quartz particles, etc.), or metal particles (gold, nickel, etc.), for example, the micro-particles 70 can all be organic particles, or all be inorganic particles, or all be metal particles; the micro-particles 70 can also be partially organic particles, partially inorganic particles, or the micro-particles 70 can also be partially organic particles, partially metal particles, or the micro-particles 70 can also be partially inorganic particles, partially metal particles, or the micro-particles 70 can also be partially organic particles, partially inorganic particles, and partially metal particles; in this way, the richness of the micro-particles 70 can provide the possibility of various combinations of the micro-particles 70, and improve the flexibility of material selection.

[0045] Figure 6 For the width size relationship between the different light emitting elements and the transfer precision area of the embodiments of the present disclosure, please refer to Figures 1 to 6 In an optional embodiment provided by the present disclosure, the micro-device substrate 100, the chip transfer area 30 further comprises a transfer precision area 50, the transfer precision area 50 is located between the light emitting element 40 and the micro-particle area 60, and the width of the transfer precision area 50 is less than or equal to 10 μm.

[0046] Specifically, the micro-device substrate 100 comprises a substrate 10 and a first adhesive layer 20 located on one side of the substrate 10, and along the direction parallel to the plane where the first adhesive layer 20 is located, the first adhesive layer 20 comprises a plurality of chip transfer areas 30 and a micro-particle area 60 located between the plurality of chip transfer areas 30, wherein the chip transfer area 30 further comprises a transfer precision area 50, the transfer precision area 50 is used to control the precision of the transfer of the light emitting element 40, and along the direction parallel to the plane where the first adhesive layer 20 is located, each transfer precision area 50 surrounds the light emitting element 40 in the chip transfer area 30, the transfer precision area 50 is located between the light emitting element 40 and the micro-particle area 60, and the width L of the transfer precision area 50 is greater than 0 and less than or equal to 10 μm, optionally, the width L of the transfer precision area 50 is 1.5 μm, optionally, the width L of the transfer precision area 50 is 3 μm, optionally, the width L of the transfer precision area 50 is 5 μm, and so on, which will not be described one by one here. When the width L of the transfer precision area 50 is equal to 0, there is no gap between the light emitting element 40 of the chip transfer area 30 and the micro-particle area 60, and when the light emitting element 40 is transferred to the micro-device substrate 100, it is easy to shift to the micro-particle area 60 to cause transfer failure, and when the width L of the transfer precision area 50 is greater than 10 μm, the width L of the transfer precision area 50 is too large, which is not conducive to the position control of the light emitting element 40, and is easy to cause poor contact with the circuit substrate. In this way, by setting the transfer precision area 50 in the chip transfer area 30, a certain allowable deviation space can be provided for the light emitting element 40, the transfer precision of the light emitting element 40 is improved, and the transfer yield is improved.

[0047] It should be noted that the "width L of the transfer precision area 50" referred to herein refers to the shortest distance in the same chip transfer area 30 along the light emitting element 40 pointing to the adjacent micro-particle area 60.

[0048] Please continue to refer to Figures 1 to 6 In an optional embodiment provided by the present disclosure, the light emitting element 40 includes a red light emitting element 41, a green light emitting element 42, and a blue light emitting element 43, wherein the width L1 of the transfer precision area 50 corresponding to the red light emitting element 41 is less than the width L2 of the transfer precision area 50 corresponding to the green light emitting element 42, or the width L1 of the transfer precision area 50 corresponding to the red light emitting element 41 is less than the width L3 of the transfer precision area 50 corresponding to the blue light emitting element 43.

[0049] Specifically, the light emitting element 40 includes a red light emitting element 41, a green light emitting element 42, and a blue light emitting element 43. Taking a micro-LED display panel as an example, due to the difference in light emitting materials of micro-LED devices of different colors in the existing display panel, the structure may also be different, and the electrical characteristics will also be different due to the influence of materials and structure, that is, different colors of light emitting elements 40 will have different light emitting efficiencies. For example, the red light emitting element 40 has lower energy due to the longer wavelength of red light, and there is more energy loss in the energy conversion process, so the light emitting efficiency and light emitting life of the red light emitting element 41 are lower than those of the green light emitting element 42 and the blue light emitting element 43. In a micro-device substrate 100 provided by the present disclosure, the width L1 of the transfer precision area 50 corresponding to the red light emitting element 41 is less than the width L2 of the transfer precision area 50 corresponding to the green light emitting element 42, and the width L1 of the transfer precision area 50 corresponding to the red light emitting element 41 is less than the width L3 of the transfer precision area 50 corresponding to the blue light emitting element 43. For example, the width L1 of the transfer precision area 50 corresponding to the red light emitting element 41 is 1.5 μm, the width L2 of the transfer precision area 50 corresponding to the green light emitting element 42 is 3 μm, and the width L3 of the transfer precision area 50 corresponding to the blue light emitting element 43 is 5 μm. Since the red light emitting element 41 has lower light emitting efficiency and light emitting life, narrowing the transfer precision area 50 corresponding to the red light emitting element 41 is beneficial to improving the transfer precision of the red light emitting element 41, reducing the displacement deviation of the red light emitting element 41, and facilitating subsequent butt joint with other elements, thereby improving the process yield. In this way, by setting the width L1 of the transfer precision area 50 corresponding to the red light emitting element 41 to be less than the width L2 of the transfer precision area 50 corresponding to the green light emitting element 42 or less than the width L3 of the transfer precision area 50 corresponding to the blue light emitting element 43, the displacement deviation of the red light emitting element 41 can be reduced, the transfer precision of the red light emitting element 41 can be improved, and the influence of the excessive displacement of the red light emitting element 41 on its light emitting efficiency and life can be reduced.

[0050] Figure 7 The schematic diagram of the particle size difference of the micro-particles around different light emitting elements is shown in the embodiment of the present disclosure, please refer to Figures 1 to 7 In an optional embodiment provided by the present disclosure, the maximum particle size of the micro-particles 70 around the chip transfer area 30 corresponding to the red light emitting element 41 is H1, and the minimum particle size is H2.

[0051] The maximum particle size of the micro-particles 70 around the chip transfer area 30 corresponding to the green light emitting element 42 or the blue light emitting element 43 is h1, and the minimum particle size is h2.

[0052] The absolute value of the difference between H1 and H2 is greater than the absolute value of the difference between h1 and h2.

[0053] Specifically, the first adhesive layer 20 in the micro-device substrate 100 includes a plurality of chip transfer areas 30, and the micro-particle area 60 is located between the plurality of chip transfer areas 30. The micro-particle area 60 contains at least two different sizes of micro-particles 70. In general, the light emitting substrate 44 of the red light emitting element 41 is a rough surface, which is different from the groove 46 arrayed with the light emitting substrate 44 of the blue light emitting element 43 or the green light emitting element 42 due to different manufacturing processes. The micro-particles 70 around the chip transfer area 30 corresponding to the red light emitting element 41 include at least two different sizes, wherein the maximum particle size is H1, and the minimum particle size is H2. The micro-particles 70 around the chip transfer area 30 corresponding to the green light emitting element 42 or the blue light emitting element 43 include at least two different sizes, wherein the maximum particle size is h1, and the minimum particle size is h2. The absolute value of the maximum difference of the particle size of the micro-particles 70 around the red light emitting element 41 is |H1-H2| which is greater than the absolute value of the maximum difference of the particle size of the micro-particles 70 around the green light emitting element 42 or the blue light emitting element 43, that is, the particle size difference of the micro-particles 70 around the red light emitting element 41 is greater than the particle size difference of the micro-particles 70 around the blue light emitting element 43 or the green light emitting element 42. That is, the contact area between the light emitting substrate 44 of the red light emitting element 41 and the micro-particles 70 at least partially offset to the micro-particle area 60 is smaller. In this way, by setting the particle size difference of the micro-particles 70 around the red light emitting element 41 to be greater than the particle size difference of the micro-particles 70 around the blue light emitting element 43 or the green light emitting element 42, the contact area between the light emitting substrate 44 of the red light emitting element 41 and the micro-particles 70 can be reduced, the adhesion between the red light emitting element 41 and the micro-particles 70 can be further reduced, and the subsequent removal of the offset red light emitting element 41 is facilitated, thereby improving the utilization rate of the micro-device substrate 100.

[0054] Figure 8 The process of transferring the light emitting element from the source substrate to the temporary substrate is shown in the embodiment of the present disclosure, Figure 9A schematic diagram of the process of transferring the light emitting element from the temporary substrate to the array substrate according to the embodiment of the present disclosure, Figure 10 A schematic diagram of the process of transferring the light emitting element from the temporary substrate to the array substrate according to the embodiment of the present disclosure, Figures 1 to 10 In an optional embodiment provided by the present disclosure, the micro device substrate 100 includes the temporary substrate 81, the temporary substrate 82, and the array substrate 80. Here, the inclusion means that the micro device substrate 100 can be embodied as the temporary substrate 81, the temporary substrate 82, or the array substrate 80.

[0055] Specifically, the micro device substrate 100 includes the temporary substrate 81 for temporarily storing the light emitting element 40, the temporary substrate 81 includes the substrate 811 and the adhesive layer 812 located on one side of the substrate 811, and along the direction parallel to the plane where the adhesive layer 812 is located, the adhesive layer 812 includes a plurality of chip transfer regions 30 and micro particle regions 60, and the light emitting element 40 is picked up for the temporary storage of the light emitting element 40.

[0056] The micro device substrate 100 further includes the temporary substrate 82 in the mass transfer process of the light emitting element 40. In the mass transfer process of the light emitting element 40, the light emitting element 40 is epitaxially grown on the source substrate 00, the light emitting element 40 includes the light emitting substrate 44 and the electrode 45, the temporary substrate 81 includes the substrate 811 and the adhesive layer 812 located on one side of the substrate 811, and along the direction parallel to the plane where the adhesive layer 812 is located, the adhesive layer 812 includes a plurality of chip transfer regions 30 and micro particle regions 60; the temporary substrate 81 is aligned with the source substrate 00, and the light emitting element 40 on the source substrate 00 is transferred to the chip transfer region 30 of the temporary substrate 81 by a peeling process, at this time, the electrode 45 of the light emitting element 40 is located between the adhesive layer 812 and the light emitting substrate 44; the temporary substrate 82 includes the substrate 822 and the adhesive layer 821 located on one side of the substrate 822, and along the direction parallel to the plane where the first adhesive layer 20 is located, the adhesive layer 821 includes a plurality of chip transfer regions 30 and micro particle regions 60; the temporary substrate 82 is aligned with the temporary substrate 81, and the light emitting element 40 on the temporary substrate 81 is transferred to the chip transfer region 30 of the temporary substrate 82, at this time, the light emitting substrate 44 of the light emitting element 40 is located between the adhesive layer 821 and the electrode 45; the array substrate 80 is aligned with the temporary substrate 82, and the light emitting element 40 on the chip transfer region 30 of the temporary substrate 82 can be transferred to the array substrate 80.

[0057] It should be noted that when the micro device substrate 100 is used as the array substrate 80, the array substrate 80 also includes the adhesive layer and the micro particle, which will not be described again.

[0058] It can be understood that the array substrate 80 is the final target substrate of the mass transfer process of the light emitting element 40. As described above, the array substrate 80 is aligned with the temporary substrate 82, so that the light emitting element 40 on the temporary substrate 82 can be transferred to the final array substrate 80 to realize the electrical connection between the light emitting element 40 and the driving device.

[0059] It can be understood that after the micro device substrate 100 completes the transfer of the light emitting element as the temporary substrate 81 or the temporary substrate 82, it can be determined whether there are residual ectopic light emitting elements 90 on the micro device substrate 100. If so, the ectopic light emitting elements 90 on the micro device substrate 100 can be removed through the water washing process in the debonding process, without the need to add new processes, which is beneficial to the recycling of the micro device substrate 100.

[0060] In summary, the present disclosure provides a micro device substrate, which comprises a substrate and a first adhesive layer located on one side of the substrate. In the direction parallel to the plane where the substrate is located, the first adhesive layer comprises a plurality of chip transfer regions and a micro-particle region located between the plurality of chip transfer regions. The micro-particle region comprises at least two types of micro-particles with different particle sizes. This can reduce the contact area between the ectopic light emitting element and the first adhesive layer, thereby reducing the adhesion and facilitating the removal of the ectopic light emitting element in the later process. When the light emitting substrate of at least part of the light emitting element comprises a patterned microstructure, the contact area between the ectopic light emitting element and the micro-particle is smaller, further reducing the adhesion. The maximum diameter of the groove in the patterned microstructure is smaller than the minimum particle size of the micro-particle, which can prevent the micro-particle from being clamped with the light emitting substrate of the ectopic light emitting element, reduce the difficulty of removing the ectopic light emitting element, and improve the recycling rate of the micro device substrate. The micro-particle with a circular arc surface can reduce the probability of impact and fragmentation with the light emitting element. When the height of the micro-particle protruding from the first adhesive layer is less than or equal to 3 μm, it is beneficial to the secondary transfer of the light emitting element and reduces the transfer difficulty. The transfer precision region is provided in the chip transfer region, which can provide a certain allowable offset space and improve the transfer yield. The width of the transfer precision region corresponding to the red light emitting element is set to be smaller than the width of the transfer precision region corresponding to the green light emitting element or the blue light emitting element, which can reduce the offset displacement of the red light emitting element and reduce the impact of the excessive offset of the red light emitting element on its light emitting efficiency and service life. The particle size difference of the micro-particles around the red light emitting element is set to be greater than the particle size difference of the micro-particles around the blue light emitting element or the green light emitting element, which can reduce the contact area between the red light emitting element and the micro-particles and further reduce the adhesion between the red light emitting element and the micro-particles.

[0061] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0062] The above description is merely a specific embodiment of this disclosure, enabling those skilled in the art to understand or implement it. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A micro device substrate, characterized by, The micro device substrate comprises a substrate and a first adhesive layer arranged on one side of the substrate; The first adhesive layer comprises a plurality of chip transfer regions and micro-particle regions between the chip transfer regions in a direction parallel to a plane in which the substrate is arranged, and a light emitting element is arranged in the chip transfer region and adhered to the first adhesive layer; The micro-particle region comprises micro-particles arranged on a side of the first adhesive layer away from the substrate; The micro-particles have smooth and non-adhesive surfaces; In a direction perpendicular to the plane in which the substrate is arranged, the micro-particles protrude from a surface of the first adhesive layer.

2. The micro device substrate of claim 1, wherein The micro-particle region comprises at least two types of micro-particles with different particle sizes.

3. The micro device substrate of claim 1, wherein The light emitting element comprises a light emitting substrate and an electrode, the light emitting substrate is arranged between the electrode and the first adhesive layer, and a surface of the light emitting substrate of at least part of the light emitting element faces the surface of the first adhesive layer and comprises a patterned microstructure.

4. The micro device substrate of claim 3, wherein The patterned microstructure comprises an array of grooves, and the minimum particle size of the micro-particles is greater than the maximum diameter of the grooves in the patterned microstructure.

5. The micro device substrate of claim 1, wherein In a direction perpendicular to the plane in which the substrate is arranged, the height of the micro-particles protruding from the first adhesive layer is less than or equal to 3 μm.

6. The micro device substrate of claim 1, wherein, The micro-particles comprise one or more of organic particles, inorganic particles, and metal particles.

7. The micro device substrate of claim 1, wherein The chip transfer region further comprises a transfer precision region, the transfer precision region is arranged between the light emitting element and the micro-particle region, and the width of the transfer precision region is less than or equal to 10 μm.

8. The micro device substrate of claim 7, wherein, The light emitting element comprises a red light emitting element, a green light emitting element, and a blue light emitting element, wherein the width of the transfer precision region corresponding to the red light emitting element is less than the width of the transfer precision region corresponding to the green light emitting element or the blue light emitting element.

9. The micro device substrate of claim 1, wherein The maximum particle size of the micro-particles around the chip transfer region corresponding to the red light emitting element is H1, and the minimum particle size is H2; The maximum particle size of the micro-particles around the chip transfer region corresponding to the green light emitting element or the blue light emitting element is h1, and the minimum particle size is h2; The absolute value of the difference between H1 and H2 is greater than the absolute value of the difference between h1 and h2.

10. The micro device substrate of claim 1, wherein, The micro device substrate comprises a temporary substrate, a transient substrate, and an array substrate.

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