Method for manufacturing semiconductor structure, method for transferring micro device, and display panel

Abstract

The application relates to a semiconductor structure preparation method, a micro device transfer method and a display panel. The semiconductor structure preparation method comprises the following steps: providing a first temporary substrate; forming a sacrifice layer on the surface of the first temporary substrate, the sacrifice layer having a plurality of spaced-apart openings; forming a weakening structure in the openings; providing a substrate, the surface of the substrate having a plurality of micro devices; bonding the micro devices and the weakening structures, the micro devices and the weakening structures corresponding to each other; removing the substrate to expose the light-emitting surface of the micro device; after removing the substrate, the light-emitting surface of the micro device has residual metal; removing the residual metal and removing the sacrifice layer to release the weakening structure. In the premise of not damaging the weakening structure, the residual metal and the sacrifice layer are removed at the same time in one step, so that the weakening structure is released, cost is saved, process complexity is reduced, the light-emitting efficiency of the light-emitting surface of the micro device is improved, and the transfer difficulty of the micro device moving to the back plate is reduced.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to methods for fabricating semiconductor structures, methods for transferring microdevices, and display panels. Background Technology

[0002] Micro LED displays, as a new generation of display technology, offer higher brightness, better luminous efficiency, and better color reproduction compared to liquid crystal displays (LCDs) and organic light-emitting diode (OLEDs). They also feature low power consumption and long lifespan, making them highly favored by the industry.

[0003] With the technological challenges brought about by the miniaturization of Micro LEDs, traditional vacuum adsorption transfer methods are no longer suitable for small-sized Micro LED chips. Currently, common mass transfer methods include electrostatic adsorption, fluid assembly, roller imprinting, van der Waals force transfer, and laser lift-off (LLO). The mainstream van der Waals force transfer and LLO technologies both require laser separation of the Micro LED chip from the substrate. Residual metals left after separation remain on the chip's light-emitting surface, hindering light emission and reducing the chip's light-emitting efficiency after mass transfer. Furthermore, these processes require the use of heat or light to de-adhere the adhesive material and transfer the Micro LED chip, resulting in complex processes that cannot achieve selective transfer, making mass transfer extremely difficult.

[0004] Therefore, improving the light extraction efficiency of the transferred Micro LED chip and reducing the complexity of the manufacturing process are urgent problems to be solved. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this application is to provide a method for preparing a semiconductor structure, a method for transferring microdevices, and a display panel, in order to solve the problems in the prior art, such as the residual metal generated by laser stripping remaining on the back of the MicroLED chip, resulting in low light extraction efficiency of the MicroLED chip, and the complexity of the mass transfer process.

[0006] A method for fabricating a semiconductor structure, comprising:

[0007] Provide a first transient substrate;

[0008] A sacrificial layer is formed on the surface of the first transient substrate, and the sacrificial layer has a plurality of spaced openings.

[0009] A weakening structure is formed within the opening;

[0010] A substrate is provided, the surface of which has a plurality of microdevices;

[0011] The microdevices are bonded to the weakened structure, and the microdevices and the weakened structures correspond one-to-one.

[0012] The substrate is removed to expose the light-emitting surface of the microdevice; after removing the substrate, the light-emitting surface of the microdevice has residual metal.

[0013] Remove the residual metal and the sacrificial layer to release the weakened structure.

[0014] In the above-mentioned semiconductor structure fabrication method, a sacrificial layer with multiple spaced openings is formed on the surface of a first transient substrate, and then a weakening structure is filled into the openings, so that the weakening structure and the sacrificial layer are spaced apart. After the microdevice is bonded to the weakening structure, the microdevice and the weakening structure correspond one-to-one. When the substrate is removed, the light-emitting surface of the microdevice retains residual metal. Finally, without damaging the weakening structure, the residual metal and the sacrificial layer are removed simultaneously in one step, so that the weakening structure can be released, saving costs, reducing the process complexity of the weakening structure, improving the luminous efficiency of the light-emitting surface of the microdevice, and reducing the difficulty of transferring the microdevice to the backplane.

[0015] Optionally, the sacrificial layer includes an indium phosphide layer. The indium phosphide layer can be removed simultaneously with the residual metal, saving costs and reducing the difficulty of preparing the weakened structure.

[0016] Optionally, removing the residual metal and the sacrificial layer to release the weakened structure includes: using an acidic solution to remove the residual metal and the sacrificial layer. The acidic solution contains acid radicals that combine with the metal ions in the residual metal and the sacrificial layer, thereby cleanly removing the residual metal and the sacrificial layer without damaging the weakened structure.

[0017] Optionally, after removing the residual metal and the sacrificial layer to release the weakened structure, the process further includes: cleaning the semiconductor structure with deionized water and drying the cleaned semiconductor structure. Deionized water cleaning can effectively remove metal compounds generated after the reaction of residual metal with acid radicals and after the reaction of acid radicals with the sacrificial layer, achieving the purpose of completely removing the residual metal and the sacrificial layer.

[0018] Optionally, an epitaxial layer is present between the microdevice and the substrate; the microdevice includes an epitaxial layer, a first electrode, and a second electrode; the epitaxial layer is located on the surface of the epitaxial layer away from the substrate; both the first electrode and the second electrode are located on the surface of the epitaxial layer away from the epitaxial layer; after the microdevice is bonded to the weakening structure, the first electrode and the second electrode are embedded within the weakening structure; the residual metal includes gallium. After the microdevice is bonded to the weakening structure, heating causes the first electrode and the second electrode to embed into the weakening structure, which can protect the two electrodes from corrosion by acidic solutions.

[0019] Optionally, removing the substrate to expose the light-emitting surface of the microdevice includes: removing the substrate using a laser lift-off process; wherein the laser energy is greater than the bandgap width of the epitaxial layer and less than the bandgap width of the substrate. During the laser lift-off process, the epitaxial layer on the light-emitting surface of the microdevice is thermally decomposed, thereby achieving separation of the epitaxial layer or the microdevice from the substrate.

[0020] Based on the same inventive concept, this application also provides a method for transferring microdevices, comprising:

[0021] The semiconductor structure is prepared using the semiconductor structure preparation method described above;

[0022] Provides transfer structure and drive backplane;

[0023] The microdevice is transferred to the surface of the drive backplane using the transfer structure.

[0024] In the above-mentioned microdevice transfer method, the semiconductor structure is prepared by a semiconductor structure preparation method with high light extraction efficiency and simple preparation process. The microdevice is then transferred to the surface of the driving backplate by the provided transfer structure and driving backplate to complete the transfer of the microdevice. This improves the overall light emission brightness of the driving backplate after transfer and reduces the difficulty of microdevice transfer.

[0025] Optionally, the material of the weakened structure includes a pyrolytic adhesive; the step of using the transfer structure to transfer the microdevice to the surface of the driving backplane includes: heating the first transient substrate, picking up the microdevice using the transfer structure, and transferring the picked-up microdevice to the surface of the driving backplane.

[0026] Optionally, the transfer structure includes a second transient substrate and a transfer member, the transfer member being located on the surface of the second transient substrate; the step of using the transfer structure to transfer the microdevice to the surface of the driving backplane includes: using the transfer member to pick up the microdevice and transferring the microdevice to the surface of the driving backplane.

[0027] Based on the same inventive concept, this application also provides a display panel, including a driving backplate and a plurality of microdevices fixed on the driving backplate, wherein the plurality of microdevices are transferred to the surface of the driving backplate using the microdevice transfer method described above.

[0028] In the aforementioned display panel, multiple microdevices are transferred to the surface of the driving backplane using a microdevice transfer method that employs microdevices with high light extraction efficiency and simple fabrication process. This results in a display panel with high luminous brightness, reducing the manufacturing cost and cycle time of the display panel. Attached Figure Description

[0029] Figure 1 This is a schematic flowchart of a method for fabricating a semiconductor structure provided in one embodiment of this application;

[0030] Figure 2 This is a partial cross-sectional schematic diagram of the formation of the sacrificial material layer provided in one embodiment of this application;

[0031] Figure 3 This is a partial cross-sectional schematic diagram of the formation of a photoresist layer provided in one embodiment of this application;

[0032] Figure 4 This is a partial cross-sectional schematic diagram of a patterned sacrificial material layer forming a sacrificial layer according to an embodiment of this application;

[0033] Figure 5 This is a partial cross-sectional schematic diagram of the formation of the pyrolytic adhesive layer provided in one embodiment of this application;

[0034] Figure 6 This is a partial cross-sectional schematic diagram of the formation of the weakened structure provided in one embodiment of this application;

[0035] Figure 7 This is a partial cross-sectional schematic diagram of the substrate and microdevice provided in one embodiment of this application;

[0036] Figure 8 This is a partial cross-sectional schematic diagram of the structure obtained by bonding the microdevice and the weakened structure according to an embodiment of this application;

[0037] Figure 9 This is a partial cross-sectional schematic diagram of the structure obtained after removing the substrate using a laser lift-off process according to an embodiment of this application;

[0038] Figure 10 This is a partial cross-sectional schematic diagram of a semiconductor structure formed by removing residual metal and sacrificial layer according to an embodiment of this application;

[0039] Figure 11 This is a schematic flowchart of a microdevice transfer method provided in one embodiment of this application;

[0040] Figure 12 This is a partial cross-sectional schematic diagram of the transfer structure provided in one embodiment of the present application located on the light-emitting surface of the microdevice;

[0041] Figure 13 This is a partial cross-sectional schematic diagram of the structure obtained after transferring the microdevice to the drive backplane in one embodiment of this application.

[0042] Explanation of reference numerals in the attached figures:

[0043] 100-Semiconductor structure, 11-First transient substrate, 12-Sacrificial layer, 121-Sacrificial material layer, 13-Photoresist layer, 131-Opening, 14-Weakening structure, 141-Pyrolytic adhesive layer;

[0044] 21-Substrate, 22-Microdevice, 221-Epilithography, 222-First electrode, 223-Second electrode, 23-Epipolar layer, 231-Residual metal;

[0045] 31-Transfer structure, 311-Second transient substrate, 312-Transfer component, 32-Drive backplate. Detailed Implementation

[0046] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application.

[0048] In existing technologies, laser lift-off is typically used to separate the substrate from the Micro LED chip. However, after lift-off, metal residue remains on the light-emitting surface of the Micro LED chip, which significantly affects its light extraction efficiency. Furthermore, the adhesive layer needs to be debonded using heat or light to transfer the Micro LED chip. These two issues complicate the Micro LED chip transfer process, making large-scale transfer difficult, resulting in low overall luminous efficiency of the fabricated display panel, long manufacturing cycles, and high costs.

[0049] Therefore, this application aims to provide a solution that can solve the above-mentioned technical problems, the details of which will be described in subsequent embodiments.

[0050] In one embodiment of this application, such as Figure 1 As shown, a method for fabricating a semiconductor structure is provided, comprising the following steps:

[0051] Step S10: Provide a first transient substrate;

[0052] Step S20: A sacrificial layer is formed on the surface of the first transient substrate, and the sacrificial layer has a plurality of spaced openings;

[0053] Step S30: Form a weakening structure within the opening;

[0054] Step S40: Provide a substrate, the surface of which has a plurality of microdevices;

[0055] Step S50: Bond the microdevices to the weakened structures, with each microdevice corresponding to a one-to-one weakened structure;

[0056] Step S60: Remove the substrate to expose the light-emitting surface of the microdevice; after removing the substrate, the light-emitting surface of the microdevice has residual metal.

[0057] Step S70: Remove residual metal and remove the sacrificial layer to release the weakened structure.

[0058] In the above-mentioned semiconductor structure fabrication method, a sacrificial layer with multiple spaced openings is formed on the surface of a first transient substrate, and then a weakening structure is filled into the openings, so that the weakening structure and the sacrificial layer are spaced apart. After the microdevice is bonded to the weakening structure, the microdevice and the weakening structure correspond one-to-one. When the substrate is removed, the light-emitting surface of the microdevice retains residual metal. Finally, without damaging the weakening structure, the residual metal and the sacrificial layer are removed simultaneously in one step, so that the weakening structure can be released, saving costs, reducing the process complexity of the weakening structure, improving the luminous efficiency of the light-emitting surface of the microdevice, and reducing the difficulty of transferring the microdevice to the backplane.

[0059] As an example, such as Figure 2 As shown, the material of the first transient substrate 11 provided in step S10 may include, but is not limited to, glass, sapphire (Al2O3) or quartz; that is, the first transient substrate 11 may include, but is not limited to, a glass substrate, a sapphire substrate or a quartz substrate.

[0060] In one embodiment, step S20: forming a sacrificial layer on the surface of the first transient substrate, the sacrificial layer having a plurality of spaced-apart openings, includes the following steps:

[0061] Step S21: A sacrificial material layer 121 is formed on the surface of the first transient substrate 11. Please refer to [link / reference needed]. Figure 2 ;

[0062] Step S22: A photoresist layer 13 is formed on the surface of the sacrificial material layer 121 away from the first transient substrate 11, such as... Figure 3 As shown;

[0063] Step S23: The sacrificial material layer 121 is patterned based on the photoresist layer 13 to form a sacrificial layer 12, wherein the sacrificial layer 12 has openings 131 arranged at intervals.

[0064] Step S24: Remove photoresist layer 13, as shown Figure 4 As shown.

[0065] As an example, a sacrificial material layer 121 may be formed on the surface of the first transient substrate 11 using a deposition process, but not limited to. Specifically, a physical vapor deposition process, a chemical vapor deposition process, or an atomic layer deposition process may be used to form the sacrificial material layer 121 on the surface of the first transient substrate 11.

[0066] As an example, the thickness of the sacrificial layer 12 can be set according to actual needs. In this embodiment, the thickness of the sacrificial layer 12 can include 5um-10um, for example, the thickness of the sacrificial layer 12 is 5um, 6um, 7um, 8um, 9um or 10um, etc.

[0067] As an example, the sacrificial layer 12 can be any material layer with an etching selectivity greater than 1 to the first transient substrate 11 and the subsequently formed weakened structure. That is, under the same etching conditions, the etching removal rate of the sacrificial layer 12 is significantly greater than the removal rate of the first transient substrate 11 and the weakened structure. This ensures that during the subsequent removal of the sacrificial layer 12, while ensuring that the sacrificial layer 12 can be removed quickly, the first transient substrate 11 and the weakened structure are hardly removed.

[0068] In one embodiment, the sacrificial layer 12 may include, but is not limited to, an indium phosphide (InP) layer.

[0069] As an example, with Figure 3 For example, the photoresist layer 13 can be made of positive photoresist. It should be understood that negative photoresist can also be used in this application, but this will not be shown here.

[0070] As an example, the sacrificial material layer 121 can be etched using, but not limited to, wet etching techniques or dry etching processes to transfer the pattern of the photoresist layer 13 onto the sacrificial layer 12.

[0071] As an example, the photoresist layer 13 can be removed using, but is not limited to, isopropanol solution, acetone solution, or resist remover.

[0072] In one embodiment, step S30: forming a weakening structure 14 within the opening 131 includes the following steps:

[0073] Step S31: Form a pyrolytic adhesive layer 141, which fills the opening 131 and covers the sacrificial layer 12, as shown. Figure 5 As shown;

[0074] Step S32: Remove the pyrolytic adhesive layer 141 located on the sacrificial layer 12 to obtain the weakened structure 14, such as Figure 6 As shown.

[0075] As an example, a pyrolytic adhesive layer 141 can be formed using, but is not limited to, spin coating techniques.

[0076] As an example, the pyrolytic adhesive layer 141 on the sacrificial layer can be removed by, but not limited to, dry etching or polishing processes. The pyrolytic adhesive layer 141 retained in the opening 131 is the weakened structure 14.

[0077] As an example, the material of the pyrolytic adhesive layer 141 may include, but is not limited to, rubber-modified bitumen (TerminalBlend 1, TB1).

[0078] As an example, the thickness of the sacrificial layer 12 can be set according to actual needs. The thickness of the sacrificial layer 12 can be the same as the thickness of the weakening structure 14, or it can be less than the thickness of the weakening structure 14, or it can be greater than the thickness of the weakening structure 14. In this embodiment, the thickness of the sacrificial layer 12 is the same as the thickness of the weakening structure 14.

[0079] In one embodiment, please refer to Figure 7 The substrate 21 provided in step S40 may include, but is not limited to, sapphire substrate, silicon carbide substrate, silicon substrate or gallium arsenide substrate, etc.; the microdevice 22 may include, but is not limited to, Micro LED chip, Mini LED chip photodetector diode, MOS device or MEMS (Micro-Electro-Mechanical System) device, etc.

[0080] In one embodiment, to facilitate the subsequent pickup of microdevices during transfer, multiple microdevices 22 are arranged at equal intervals on the surface of the substrate 21. The spacing can be determined according to the actual process parameters, and this application does not limit this. Of course, in other embodiments, multiple microdevices 22 may also be arranged at non-equal intervals on the surface of the substrate 21.

[0081] In one embodiment, an epitaxial layer 23 is provided between the microdevice 22 and the substrate 21; in this application, the microdevice 22 includes an epitaxial layer 221, a first electrode 222, and a second electrode 223; the epitaxial layer 221 is located on the surface of the epitaxial layer 23 away from the substrate 21; both the first electrode 222 and the second electrode 223 are located on the surface of the epitaxial layer 221 away from the epitaxial layer 23. A gap is provided between the first electrode 222 and the second electrode 223.

[0082] As an example, the material of the epitaxial layer 23 may include, but is not limited to, GaN, etc.; the material and shape of the first electrode 222 and the second electrode 223 are not limited, and the material of the electrodes may include, but is not limited to, alloy materials formed by one or any combination of Cr, Ti, Al, Ni, Pt, W, Pb, Rh, Sn, Cu and Ag. The first electrode 222 may be a P electrode and the second electrode 223 may be an N electrode; or the first electrode 222 may be an N electrode and the second electrode 223 may be a P electrode.

[0083] In one embodiment, the number of microdevices 22 can be the same as the number of weakening structures 14, such as... Figure 8 As shown, in step S50, the microdevice 22 can be flip-chip bonded to the weakened structure 14, with each microdevice 22 corresponding to one of the weakened structures 14. Utilizing the material properties of the weakened structure 14, it is heated to embed the first electrode 222 and the second electrode 223 within the microdevice 22 into the weakened structure 14, thereby protecting the electrodes from damage during the removal of residual metal 231 and the sacrificial layer 12. Of course, in other examples, the surfaces of the first electrode 222 and the second electrode 223 away from the epitaxial layer 221 can also contact the surface of the weakened structure 14 away from the first transient substrate 11; in this case, the first electrode 222 and the second electrode 223 are not embedded within the weakened structure 14.

[0084] In one embodiment, such as Figure 9 As shown, step S60: removing the substrate 21 to expose the light-emitting surface of the microdevice 22 includes the following steps:

[0085] Step S61: Remove substrate 21 using laser lift-off process; wherein the laser energy is greater than the bandgap width of epitaxial layer 23 and less than the bandgap width of substrate 21.

[0086] For ease of understanding, in this embodiment, the epitaxial layer 23 is made of GaN, and the substrate 21 is made of sapphire. The bandgap of the GaN epitaxial layer is 3.3 eV, and the bandgap of the sapphire substrate is 9.9 eV. The laser energy is adjusted to be between 3.3 eV and 9.9 eV. The ultraviolet laser source irradiates the microdevice 22 through the sapphire substrate, causing the GaN epitaxial layer in contact with the sapphire substrate to undergo a thermal decomposition reaction, generating metallic Ga and nitrogen gas (N2), thereby achieving the separation of the microdevice 22 from the substrate 21. The remaining metallic Ga is retained on the light-emitting surface of the microdevice 22.

[0087] In one embodiment, the light-emitting surface is the contact surface between the microdevice 22 and the epitaxial layer 23; after removing the substrate 21, the light-emitting surface of the microdevice 22 has residual metal 231, which includes gallium.

[0088] In one embodiment, step S70: removing the residual metal 231 and removing the sacrificial layer 12 to release the weakened structure 14 includes the following steps:

[0089] Step S71: Use an acidic solution to remove residual metal 231 and sacrificial layer 12. The acidic solution contains anions that combine with the metal ions in residual metal 231 and sacrificial layer 12, thereby cleanly removing residual metal 231 and sacrificial layer 12 without damaging the weakened structure 14.

[0090] As an example, acidic solutions may include, but are not limited to, sulfuric acid, hydrochloric acid, phosphoric acid, or hydrofluoric acid, etc. In this application, methods such as immersion, spraying, or atomization may be used to... Figure 9 The structure shown is processed; the acidic solution is illustrated using hydrochloric acid as an example. The concentration of hydrochloric acid can be selected according to actual needs. In this embodiment, a 37% hydrochloric acid solution (37% HCl·H2O solution) is selected to remove residual metal 231 and sacrificial layer 12. Sacrificial layer 12 can be removed simultaneously with residual metal 231, saving costs and reducing the difficulty of the preparation process of the weakened structure.

[0091] In one embodiment, the prepared 37% HCl·H2O solution can be stored in a beaker, and... Figure 9 The structure containing the microdevice 22 is immersed in a 37% HCl·H2O solution. The weakened structure 14 is made of olefinic materials, which are resistant to strong acids and alkalis. Therefore, the hydrochloric acid solution has good selectivity for the weakened structure 14, removing the remaining residual metal 231 and sacrificial layer 12 without damaging the weakened structure 14, thus obtaining the semiconductor structure 100. Figure 10As shown, the semiconductor structure 100 obtained by the above preparation method improves the light extraction efficiency of the microdevice 22, reduces the number of process steps, saves costs, and reduces the difficulty of fabricating the weakened structure 14; at the same time, the prepared weakened structure 14 can reduce the difficulty of the microdevice 22 in the mass transfer process.

[0092] As an example, the soaking time can be set according to actual needs. In this embodiment, the soaking time can include 10s-30s; for example, the soaking time can be 10s, 15s, 20s, 25s or 30s, etc.

[0093] When the sacrificial layer is an indium phosphide layer, the reaction between the indium phosphide layer and hydrochloric acid is as follows:

[0094] InP + 3HCl = InCl3 + pH3↑;

[0095] The reaction between metallic gallium and hydrochloric acid is as follows:

[0096] 2Ga + 6HCl = 2GaCl3 + 3H2↑.

[0097] In one embodiment, after step S70—removing the residual metal 231 and the sacrificial layer 12 to release the weakened structure 14—the method further includes: cleaning the semiconductor structure 100 with deionized water and drying the cleaned semiconductor structure 100. Cleaning with deionized water can effectively remove the metal compounds generated after the reaction of the residual metal 231 with acid radicals and after the reaction of acid radicals with the sacrificial layer 12, achieving the purpose of completely removing the residual metal 231 and the sacrificial layer 12.

[0098] As an example, the metal compound may include, but is not limited to, InCl3 or GaCl3. The drying temperature can be set according to actual needs. In this embodiment, the drying temperature may include 40℃-80℃, for example, the drying temperature may be 40℃, 50℃, 60℃, 70℃, 75℃ or 80℃, etc.

[0099] In one embodiment of this application, please continue to refer to Figure 10 The semiconductor structure 100 includes a first transient substrate 11, a weakening structure 14, and a plurality of microdevices 22; the weakening structure 14 is located between the microdevices 22 and the first transient substrate 11; the microdevices 22 are partially embedded in the weakening structure 14, and the light-emitting surface of the microdevices 22 is away from the weakening structure 14.

[0100] In one embodiment of this application, such as Figure 11 As shown, a method for transferring microdevices is also provided, comprising the following steps:

[0101] Step S100: Prepare semiconductor structure 100 using the semiconductor structure preparation method described above, such as... Figure 10 As shown;

[0102] Step S200: Provide the transfer structure 31 and the drive backplane 32;

[0103] Step S300: Use transfer structure 31 to transfer microdevice 22 onto the surface of drive backplane 32, such as... Figure 13 As shown.

[0104] In the above-mentioned microdevice transfer method, the semiconductor structure is prepared by a semiconductor structure preparation method with high light extraction efficiency and simple preparation process. The microdevice is then transferred to the surface of the driving backplate by the provided transfer structure and driving backplate to complete the transfer of the microdevice. This improves the overall light emission brightness of the driving backplate after transfer and reduces the difficulty of microdevice transfer.

[0105] As an example, the surface of the drive backplate 32 has contact electrodes (not shown in the figure), which correspond to the first electrode 222 and the second electrode 223. The number of contact electrodes is greater than the sum of the number of the first electrode 222 and the second electrode 223. After selective pickup, at least a portion of the contact electrodes come into contact with the first electrode 222 and the second electrode 223.

[0106] In one embodiment, the material of the weakening structure 14 includes a pyrolytic adhesive; Step S300: Transferring the microdevice 22 to the surface of the driving backplane 32 using the transfer structure 31 includes the following steps:

[0107] Step S301: Heat the first transient substrate 11 and use the transfer structure 31 to pick up the microdevice 22;

[0108] Step S302: Transfer the picked-up microdevice 22 to the surface of the drive backplane 32.

[0109] As an example, the heating temperature of the first transient substrate 11 can be adaptively set according to the material of the transfer structure 31. In this embodiment, the heating temperature of the first transient substrate 11 may include 40°C-70°C, for example, the heating temperature may be 40°C, 50°C, 60°C, 65°C or 70°C, etc.

[0110] In one embodiment, such as Figure 12 As shown, the transfer structure 31 includes a second transient substrate 311 and a transfer member 312, with the transfer member 312 located on the surface of the second transient substrate 311. Transferring the microdevice 22 to the surface of the driving backplane 32 using the transfer structure 31 includes the following steps:

[0111] Step S310: Use transfer member 31 to pick up microdevice 22 and transfer microdevice 22 to the surface of drive backplane 32. Please refer to [link / reference needed]. Figure 13 .

[0112] As an example, all microdevices 22 can be picked up, or only a portion of the microdevices 22 can be picked up; the material of the second transient substrate 311 may include, but is not limited to, a glass substrate, a sapphire substrate (Al2O3), or a quartz substrate. The material of the first transient substrate 11 and the second transient substrate 311 may be the same or different. The transfer member 312 may include, but is not limited to, a polydimethylsiloxane stamp (PDMS stamp), which can directly pick up the microdevices 22 on the first transient substrate 11 without heating due to its own adhesion.

[0113] In one embodiment of this application, a display panel is also provided, including a driving backplate 32 and a plurality of microdevices 22 fixed on the driving backplate 32. The plurality of microdevices 22 are transferred to the surface of the driving backplate 32 using the microdevice transfer method described above.

[0114] In the aforementioned display panel, multiple microdevices are transferred to the surface of the driving backplane using a microdevice transfer method that employs microdevices with high light extraction efficiency and simple fabrication process. This results in a display panel with high luminous brightness, reducing the manufacturing cost and cycle time of the display panel.

[0115] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A method for fabricating a semiconductor structure, characterized in that, include: Provide a first transient substrate; A sacrificial layer is formed on the surface of the first transient substrate, and the sacrificial layer has a plurality of spaced openings. The sacrificial layer includes an indium phosphide layer; A weakening structure is formed within the opening; A substrate is provided, the surface of which has a plurality of microdevices; The microdevices are bonded to the weakened structure, and the microdevices and the weakened structures correspond one-to-one. Remove the substrate to expose the light-emitting surface of the microdevice; After the substrate is removed, the light-emitting surface of the microdevice has residual metal. Remove the residual metal and the sacrificial layer to release the weakened structure; The removal of the residual metal and the removal of the sacrificial layer to release the weakened structure includes: The residual metal and the sacrificial layer are removed using an acidic solution.

2. The method for preparing the semiconductor structure according to claim 1, characterized in that, After removing the residual metal and the sacrificial layer to release the weakened structure, the method further includes: The semiconductor structure was cleaned with deionized water and then dried.

3. The method for preparing the semiconductor structure as described in claim 1 or 2, characterized in that, An epitaxial layer is present between the microdevice and the substrate; the microdevice includes an epitaxial layer, a first electrode, and a second electrode; the epitaxial layer is located on the surface of the epitaxial layer away from the substrate; both the first electrode and the second electrode are located on the surface of the epitaxial layer away from the epitaxial layer; after the microdevice is bonded to the weakening structure, the first electrode and the second electrode are embedded in the weakening structure; the residual metal includes gallium.

4. The method for preparing a semiconductor structure as described in claim 3, characterized in that, The removal of the substrate to expose the light-emitting surface of the microdevice includes: The substrate is removed using a laser lift-off process; wherein the laser energy is greater than the bandgap width of the epitaxial layer and less than the bandgap width of the substrate.

5. A method for transferring microdevices, characterized in that, include: The semiconductor structure is prepared using the semiconductor structure preparation method according to any one of claims 1-4; Provides transfer structure and drive backplane; The microdevice is transferred to the surface of the drive backplane using the transfer structure.

6. The microdevice transfer method as described in claim 5, characterized in that, The material of the weakened structure includes a pyrolytic adhesive; the transfer of the microdevice onto the surface of the drive backplane using the transfer structure includes: The first transient substrate is heated, and the microdevice is picked up using the transfer structure. The picked-up microdevice is transferred to the surface of the drive backplane.

7. The microdevice transfer method as described in claim 6, characterized in that, The transfer structure includes a second transient substrate and a transfer member, wherein the transfer member is located on the surface of the second transient substrate; The step of transferring the microdevice to the surface of the driving backplane using the transfer structure includes: The transfer member is used to pick up the microdevice and transfer the microdevice to the surface of the drive backplane.

8. A display panel, characterized in that, It includes a drive backplane and a plurality of microdevices fixed to the drive backplane, wherein the plurality of microdevices are transferred to the surface of the drive backplane using the microdevice transfer method as described in any one of claims 5-7.

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