Mass transfer method and micro light emitting diode

Abstract

The disclosure provides a mass transfer method and a micro light emitting diode, and belongs to the technical field of semiconductor preparation. The mass transfer method comprises the following steps: preparing a conductive film layer on one side of a circuit substrate; coating a photosensitive adhesive layer on the side of the conductive film layer away from the circuit substrate, the photosensitive adhesive layer having a photosensitive self-heating expansion characteristic; patterning the photosensitive adhesive layer through a yellow light process to obtain an auxiliary transfer film, the auxiliary transfer film having a plurality of accommodation holes; placing the auxiliary transfer film and a wafer to be transferred in a relative position, so that the crystal grains of the wafer to be transferred are located in the corresponding accommodation holes; irradiating the auxiliary transfer film with laser to make the auxiliary transfer film expand by heat, so as to clamp the crystal grains in the corresponding accommodation holes; and separating the auxiliary transfer film from the wafer to be transferred, so that the crystal grains are peeled off and remain in the accommodation holes. The disclosure can improve the yield and efficiency of mass transfer.

Description

Technical Field

[0001] This disclosure belongs to the field of semiconductor fabrication technology, and specifically relates to a mass transfer method and a micro light-emitting diode. Background Technology

[0002] Micro LED (Micro Light Emitting Diode) is a new type of semiconductor display device.

[0003] In the fabrication of miniature light-emitting diodes (LEDs), it is necessary to transfer the wafer's dies to a substrate. Because the dies are extremely small, the number of dies that need to be transferred is enormous. This process of transferring dies is called mass transfer.

[0004] Because of the small size and large number of chips, the workload of mass transfer is enormous, and conventional chip transfer methods for LEDs cannot be applied to miniature LEDs. Summary of the Invention

[0005] This disclosure provides a mass transfer method and a miniature light-emitting diode, which can improve the yield and efficiency of mass transfer. The technical solution is as follows:

[0006] On one hand, embodiments of this disclosure provide a mass transfer method, including:

[0007] A conductive film layer is prepared on one side of the circuit substrate;

[0008] A photosensitive adhesive layer is coated on the side of the conductive film layer that is opposite to the circuit substrate, and the photosensitive adhesive layer has photosensitive self-thermal expansion characteristics.

[0009] The photosensitive adhesive layer is patterned using a photolithography process to obtain an auxiliary transfer film, which has multiple accommodating holes.

[0010] The auxiliary transfer film is positioned opposite to the wafer to be transferred, such that the grains of the wafer to be transferred are located in the corresponding receiving holes;

[0011] The auxiliary transfer film is irradiated with a laser, causing it to expand due to heat, thereby clamping the grains within the corresponding receiving holes.

[0012] The auxiliary transfer film is separated from the wafer to be transferred, so that the grains are stripped off and retained in the receiving hole.

[0013] In one implementation of this disclosure, a photosensitive adhesive layer is coated on the side of the conductive film layer facing away from the circuit substrate, including:

[0014] Provide a main adhesive material, wherein the main adhesive material is any one of polydimethylsiloxane adhesive, epoxy resin adhesive, and synthetic silicone;

[0015] Black glue is added to the main adhesive material;

[0016] The main adhesive material, doped with black glue, is spin-coated onto the side of the conductive film layer facing away from the circuit substrate to form the photosensitive adhesive layer.

[0017] In one implementation of this disclosure, a photosensitive adhesive layer is coated on the side of the conductive film layer facing away from the circuit substrate, and the method further includes:

[0018] The thickness of the photosensitive adhesive layer is 1 to 2 μm less than the thickness of the grains.

[0019] In one implementation of this disclosure, the auxiliary transfer film is irradiated with a laser, comprising:

[0020] Determine the irradiation area;

[0021] The auxiliary transfer film is irradiated with a laser based on the irradiated area.

[0022] In one implementation of this disclosure, determining the irradiation area includes:

[0023] Identify the irradiation receiving hole, wherein the irradiation receiving hole is the receiving hole that needs to accommodate the grain;

[0024] The irradiation area is determined based on the area where the irradiation receiving hole is located.

[0025] In one implementation of this disclosure, separating the auxiliary transfer film from the wafer to be transferred includes:

[0026] The circuit substrate or the wafer to be transferred is moved along a direction perpendicular to the circuit substrate, so that a gap of 3 to 4 μm is generated between the auxiliary transfer film and the wafer to be transferred.

[0027] In one implementation of this disclosure, after separating the auxiliary transfer film from the wafer to be transferred, the method further includes:

[0028] Stop irradiating with laser light and allow the auxiliary transfer film to cool down and shrink back.

[0029] The conductive film layer and the grains retained in the accommodating hole are electrically connected.

[0030] In one implementation of this disclosure, electrically connecting the conductive film layer and the grain retained within the accommodating hole includes:

[0031] The conductive film layer and the grains retained in the accommodating hole are electrically connected by any one of the following methods: high temperature, high pressure, or reflow.

[0032] In one implementation of this disclosure, a conductive film layer is prepared on one side of a circuit substrate, including:

[0033] An anisotropic conductive adhesive film is attached to one side of the circuit board; or,

[0034] Metal solder joints are prepared on one side of the circuit board.

[0035] On the other hand, embodiments of this disclosure provide a miniature light-emitting diode (LED) fabricated using the mass transfer method described in the preceding aspect.

[0036] The beneficial effects of the technical solutions provided in this disclosure include at least the following:

[0037] A conductive film and an auxiliary transfer film are sequentially disposed on one side of a circuit substrate. The auxiliary transfer film has multiple receiving holes through which the dies of the wafer to be transferred can be accommodated. During mass transfer, the auxiliary transfer film is positioned opposite the wafer to be transferred, so that the dies of the wafer to be transferred are located in the corresponding receiving holes. Then, the auxiliary transfer film is irradiated with a laser. Due to the photosensitive self-thermal expansion properties of the auxiliary transfer film, it expands upon heating after being irradiated by the laser, thereby clamping the dies in the corresponding receiving holes. Finally, the auxiliary transfer film is separated from the wafer to be transferred. Because the dies are clamped by the auxiliary transfer film, they are peeled off from the wafer under the action of friction and remain in the receiving holes. Under the action of the conductive film, the dies and the circuit substrate are electrically connected, completing the mass transfer.

[0038] In other words, by using an auxiliary transfer film to hold the die, the die can be positioned and peeled off simultaneously, allowing the die to be transferred directly from the wafer to the circuit board. This not only improves the yield of mass transfer but also increases its efficiency. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a flowchart of a mass transfer method provided in an embodiment of this disclosure;

[0041] Figure 2This is a flowchart of another mass transfer method provided in this disclosure embodiment;

[0042] Figure 3 This is a schematic diagram of the mass transfer process provided in an embodiment of this disclosure;

[0043] Figure 4 This is a schematic diagram of the mass transfer process provided in an embodiment of this disclosure;

[0044] Figure 5 This is a schematic diagram of the mass transfer process provided in an embodiment of this disclosure;

[0045] Figure 6 This is a schematic diagram of the mass transfer process provided in an embodiment of this disclosure;

[0046] Figure 7 This is a schematic diagram of the mass transfer process provided in an embodiment of this disclosure;

[0047] Figure 8 This is a schematic diagram of the mass transfer process provided in an embodiment of this disclosure;

[0048] Figure 9 This is a schematic diagram of the mass transfer process provided in an embodiment of this disclosure.

[0049] The symbols in the diagram represent the following meanings:

[0050] 10. Circuit board;

[0051] 20. Conductive film layer;

[0052] 30. Photosensitive adhesive layer;

[0053] 40. Auxiliary transfer film; 410. Reception hole; 420. Toothed structure;

[0054] 100. Wafers to be transferred;

[0055] 200, grain size.

[0056] The accompanying drawings have illustrated specific embodiments of this disclosure, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concepts of this disclosure to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of this disclosure clearer, the embodiments of this disclosure will be described in further detail below with reference to the accompanying drawings.

[0058] To better understand the mass transfer method provided in the embodiments of this disclosure, several mass transfer methods in related technologies will be introduced below.

[0059] In related technologies, there are several methods for mass transfer.

[0060] The first method involves creating an adhesive stamp transfer head based on the die size, spacing, and arrangement. The die is then picked up by the stamp transfer head and placed onto the circuit board. Finally, the die and circuit board are electrically connected. This method has low transfer efficiency and is difficult to apply on a large commercial scale.

[0061] The second method involves laser-based die removal. However, to prevent the removed die from impacting the circuit board at high speed, the die must first be transferred to a colloidal layer with suitable hardness and thickness before being transferred back to the circuit board. This method has a higher transfer efficiency than the first, but it is still relatively low and difficult to apply to large-scale commercial use.

[0062] It is evident that both of the mass transfer methods in the relevant technologies are inefficient and difficult to apply to large-scale commercial use.

[0063] To address the aforementioned technical problems, this disclosure provides a mass transfer method. Figure 1 For a flowchart of this mass transfer method, see [link to flowchart]. Figure 1 In this embodiment, the mass transfer method includes:

[0064] Step 101: Prepare a conductive film layer on one side of the circuit board.

[0065] Step 102: Apply a photosensitive adhesive layer to the side of the conductive film layer that is opposite to the circuit board. The photosensitive adhesive layer has photosensitive self-thermal expansion characteristics.

[0066] Step 103: Pattern the photosensitive adhesive layer through a photolithography process to obtain an auxiliary transfer film, which has multiple accommodating holes.

[0067] Step 104: Position the auxiliary transfer film opposite to the wafer to be transferred, so that the grains of the wafer to be transferred are located in the corresponding receiving holes.

[0068] Step 105: The auxiliary transfer film is irradiated by laser, causing it to expand due to heat, so as to clamp the grains in the corresponding receiving holes.

[0069] Step 106: Separate the auxiliary transfer film from the wafer to be transferred, so that the grains are peeled off and retained in the receiving hole.

[0070] A conductive film and an auxiliary transfer film are sequentially disposed on one side of a circuit substrate. The auxiliary transfer film has multiple receiving holes through which the dies of the wafer to be transferred can be accommodated. During mass transfer, the auxiliary transfer film is positioned opposite the wafer to be transferred, so that the dies of the wafer to be transferred are located in the corresponding receiving holes. Then, the auxiliary transfer film is irradiated with a laser. Due to the photosensitive self-thermal expansion properties of the auxiliary transfer film, it expands upon heating after being irradiated by the laser, thereby clamping the dies in the corresponding receiving holes. Finally, the auxiliary transfer film is separated from the wafer to be transferred. Because the dies are clamped by the auxiliary transfer film, they are peeled off from the wafer under the action of friction and remain in the receiving holes. Under the action of the conductive film, the dies and the circuit substrate are electrically connected, completing the mass transfer.

[0071] In other words, by using the auxiliary transfer film to hold the die, the die is simultaneously positioned and peeled off, enabling the die to be transferred directly from the wafer to the circuit board 10. This not only improves the yield of mass transfer but also increases the efficiency of mass transfer.

[0072] Figure 2 A flowchart of another mass transfer method provided in this disclosure embodiment, combined with Figure 2 In this embodiment, the mass transfer method includes:

[0073] Step 201: Prepare a conductive film layer 20 on one side of the circuit substrate 10 (see...) Figure 3 ).

[0074] In some examples, step 201 is performed in the following manner.

[0075] An anisotropic conductive film (ACF) is attached to one side of the circuit board 10.

[0076] In the above implementation, the anisotropic conductive adhesive film mainly comprises an adhesive and conductive particles. The adhesive is epoxy resin, which serves as the main component, acting as both a bond between the circuit board 10 and the die 200, and a carrier for the conductive particles. The conductive particles are doped into the adhesive, thus providing conductivity. Using the anisotropic conductive adhesive film as the conductive film layer 20 simplifies the fabrication process and effectively improves the efficiency of mass transfer, as the anisotropic conductive adhesive film can be directly attached to the circuit board.

[0077] In other examples, step 201 is performed in the following manner.

[0078] Metal solder joints are prepared on one side of the circuit board 10.

[0079] In the above implementation, the electrical connection between the circuit board 10 and the die 200 is achieved by using metal solder joints as the conductive film layer 20. It is worth noting that although the process flow for metal solder joints is more complex than that for anisotropic conductive films, metal solder joints also have some other advantages. For example, metal solder joints offer stronger bonding and higher reliability of the electrical connection. This effectively improves the yield of mass transfer.

[0080] Of course, the execution method of step 201 can be selected according to actual needs. For example, if it is necessary to improve the efficiency of mass transfer, then an anisotropic conductive adhesive film can be selected as the conductive film layer 20. If it is necessary to improve the yield of mass transfer, then metal welding joints can be selected as the conductive film layer 20. This disclosure does not limit this.

[0081] Step 202: A photosensitive adhesive layer 30 is coated on the side of the conductive film layer 20 that faces away from the circuit board 10. The photosensitive adhesive layer 30 has photosensitive self-thermal expansion characteristics (see...). Figure 4 ).

[0082] In this embodiment, step 202 is performed in the following manner.

[0083] Step 2021: Provide the main adhesive material, which is any one of polydimethylsiloxane adhesive (PDMS), epoxy resin adhesive, or synthetic silicone.

[0084] In the above implementation methods, polydimethylsiloxane adhesive, epoxy resin adhesive, and synthetic silicone all have photosensitive self-thermal expansion characteristics. After being irradiated by laser, their own temperature rises rapidly, and their volume increases accordingly after being heated.

[0085] It is worth noting that the material of the main adhesive can be selected according to actual needs, and this disclosure does not impose any restrictions on it.

[0086] For example, the thickness of the photosensitive adhesive layer 30 is 1 to 2 μm less than the thickness of the grain 200.

[0087] The thickness of the photosensitive adhesive layer 30 largely determines the thickness of the auxiliary transfer film 40 prepared in subsequent steps. This design of the photosensitive adhesive layer 30's thickness serves two purposes: firstly, it avoids interference and collisions between the auxiliary transfer film 40 and the wafer 100 to be transferred in subsequent steps due to excessive thickness, preventing the die 200 from failing to make sufficient contact with the conductive film layer 20; secondly, it avoids insufficient thickness of the auxiliary transfer film 40, which would result in the die 200 not being securely held in subsequent steps.

[0088] Step 2022: Add black glue to the main adhesive material.

[0089] In the above implementation, the addition of black adhesive to the main adhesive material makes the photosensitive adhesive layer 30 appear black overall, thus making the subsequently prepared auxiliary transfer film 40 black as well. The black auxiliary transfer film 40 can mask defects or the inherent color of the backplane or substrate of the micro-LED, resulting in better overall color consistency for the micro-LED.

[0090] It should be noted that "black glue" refers to a black adhesive material, and the material of the black glue is the same as that of the main adhesive material. For example, if the main adhesive material is epoxy resin, then the black glue is black epoxy resin. By incorporating the black glue into the main adhesive material, the photosensitive adhesive layer 30 becomes entirely black.

[0091] Step 2023: Spin-coat the main adhesive material doped with black glue onto the side of the conductive film layer 20 that is opposite to the circuit substrate 10 to form the photosensitive adhesive layer 30.

[0092] Step 203: The photosensitive adhesive layer 30 is patterned using a photolithography process to obtain an auxiliary transfer film 40, which has multiple accommodating holes 410 (see...). Figure 5 ).

[0093] In the above implementation, the photolithography process includes exposure, development, etching (dry etching), and resist stripping. The photolithography process can pattern the photosensitive adhesive layer 30 to form an auxiliary transfer film 40 with multiple accommodating holes 410.

[0094] It is worth noting that the arrangement of the receiving holes 410 is related to the patterning result, and can be designed according to actual needs, such as in a matrix arrangement, etc., which is not limited in this disclosure. In addition, the shape of the receiving holes 410 is also related to the patterning result, and can be designed according to actual needs, such as rectangular, circular, etc., which is not limited in this disclosure.

[0095] In other embodiments, by patterning the photosensitive adhesive layer 30, a tooth-like structure 420 can be formed on the inner sidewall of the accommodating hole 410 (see [link]). Figure 6 The toothed structure 420 helps to stabilize the grains 200 in the transfer film 40.

[0096] Step 204: Position the auxiliary transfer film 40 opposite to the wafer 100 to be transferred, such that the die 200 of the wafer 100 to be transferred is located within the corresponding receiving hole 410 (see...). Figure 7 ).

[0097] In the above implementation, after the auxiliary transfer film 40 is aligned with the wafer 100 to be transferred, the circuit substrate 10 or the wafer 100 to be transferred is moved in a direction perpendicular to the circuit substrate 10, so that the circuit substrate 10 and the wafer 100 to be transferred move towards each other until the die 200 of the wafer 100 to be transferred moves into the corresponding receiving hole 410.

[0098] In other embodiments, if the inner wall of the receiving hole 410 has a toothed structure 420, then when the grain 200 is located in the receiving hole 410, the toothed structure 420 can be opposite to the grain 200.

[0099] Step 205: The auxiliary transfer film 40 is irradiated with a laser, causing it to expand due to heat, thereby clamping the grain 200 within the corresponding receiving hole 410 (see...). Figure 8 , Figure 8 The solid arrow in the middle represents a laser.

[0100] In the above implementation, after the auxiliary transfer film 40 is heated and expands, it will squeeze the grain 200 located in the receiving hole 410, thereby increasing the friction between the auxiliary transfer film 40 and the grain 200, which is beneficial to drive the grain 200 to move in subsequent steps, thereby realizing the peeling of the grain 200.

[0101] In other embodiments, if the inner sidewall of the receiving hole 410 has a toothed structure 420, then after the auxiliary transfer film 40 expands due to heat, the toothed structure 420 also expands accordingly, thereby tightly abutting against the grain 200 and further increasing the frictional force between the auxiliary transfer film 40 and the grain 200. Additionally, the sidewall of the grain 200 corresponding to the position of the toothed structure 420 can also have a recessed structure, so that the toothed structure 420 can be inserted into the recessed structure after thermal expansion, thereby further improving the reliability of peeling off the grain 200.

[0102] In this embodiment, step 205 is performed in the following manner.

[0103] Step 2051: Determine the irradiation area.

[0104] For example, in step 2051, the irradiation receiving hole 410 is first determined, which is the receiving hole 410 that needs to accommodate the die 200. Then, the irradiation area is determined according to the area where the irradiation receiving hole 410 is located.

[0105] In the above implementation method, by determining the irradiation area, the accuracy of subsequent laser irradiation can be improved, thereby ensuring that the parts that need to expand expand, while the parts that do not need to expand do not expand.

[0106] Step 2052: Based on the irradiation area, transfer the thin film 40 by laser irradiation.

[0107] In the above implementation, since laser irradiation is based on the irradiation area, the accuracy of laser irradiation is very high, thereby improving the yield of mass transfer.

[0108] Step 206: Separate the auxiliary transfer film 40 from the wafer 100 to be transferred, so that the die 200 is peeled off and retained in the receiving hole 410 (see...). Figure 9 It is worth noting that, although Figure 9 The illustration only shows one grain 200 being stripped, but the number of grains 200 stripped can be adjusted according to actual needs, and this disclosure does not limit this.

[0109] For example, the circuit substrate 10 or the wafer to be transferred 100 is moved along a direction perpendicular to the circuit substrate 10, so that a gap of 3 to 4 μm is generated between the auxiliary transfer film 40 and the wafer to be transferred 100.

[0110] In the above implementation, the gap size between the auxiliary transfer film 40 and the wafer 100 to be transferred is determined by the travel of the circuit board 10 or the wafer 100 to be transferred. Designing the gap to be 3-4 μm can, on the one hand, avoid incomplete peeling of the die 200 due to an excessively small gap, and on the other hand, avoid unnecessary shaking due to an excessively large gap.

[0111] Step 207: Stop irradiating with the laser and wait for the auxiliary transfer film to cool down and shrink back to its original size.

[0112] In the above implementation, after the laser stops irradiating the auxiliary transfer film 40, the auxiliary transfer film 40 stops heating and gradually shrinks back to its normal volume.

[0113] Step 208: Electrically connect the conductive film layer 20 and the grain 200 retained in the accommodating hole 410.

[0114] For example, in step 208, the conductive film layer 20 and the grains 200 retained in the accommodating hole 410 are electrically connected by any one of high temperature, high pressure, or reflow.

[0115] In the above implementation, since the thickness of the photosensitive adhesive layer 30 is 1-2 μm less than the thickness of the die 200, the die 200 can make sufficient contact with the conductive film layer 20. Based on this, by matching the conductive film layer and employing any one of the corresponding methods—high temperature, high pressure, or reflow—a stable mechanical and electrical connection between the die 200 and the conductive film layer 20 can be ensured, thereby guaranteeing the reliability of the electrical connection and improving the yield of mass transfer.

[0116] This disclosure provides a miniature light-emitting diode (LED) that, through... Figure 1 or Figure 2 Prepared using the mass transfer method shown.

[0117] Because this miniature light-emitting diode is through Figure 1 or Figure 2 The mass transfer method shown in the figure ensures the yield and efficiency of mass transfer during the fabrication process, especially during the mass transfer process, thereby guaranteeing the quality of the micro LED.

[0118] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” “third,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an” or “a” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “comprising” or “including” and similar terms mean that the elements or objects preceding “comprising” or “including” encompass the elements or objects listed following “comprising” or “including” and their equivalents, and do not exclude other elements or objects. The terms “connected” or “linked” and similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” “right,” etc., are used only to indicate relative positional relationships; when the absolute position of the described objects changes, the relative positional relationship may also change accordingly.

[0119] The above description is merely an optional embodiment of this disclosure and is not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. A mass transfer method characterized by, Comprising: Preparation of a conductive film layer (20) on one side of a circuit substrate (10); Coating a photosensitive adhesive layer (30) on the side of the conductive film layer (20) away from the circuit substrate (10), the photosensitive adhesive layer (30) having photosensitive self-heating expansion characteristics; Through the yellow light process, the photosensitive adhesive layer (30) is patterned to obtain an auxiliary transfer film (40), the auxiliary transfer film (40) has a plurality of accommodation holes (410); The auxiliary transfer film (40) is placed opposite to the wafer to be transferred (100), so that the die (200) of the wafer to be transferred (100) is located in the corresponding accommodation hole (410); By laser irradiation of the auxiliary transfer film (40), the auxiliary transfer film (40) is heated and expanded to clamp the die (200) in the corresponding accommodation hole (410); The auxiliary transfer film (40) is separated from the wafer to be transferred (100), so that the die (200) is peeled off and remains in the accommodation hole (410).

2. The mass transfer method of claim 1, wherein, Coating a photosensitive adhesive layer (30) on the side of the conductive film layer (20) away from the circuit substrate (10), comprising: Providing a main adhesive material, the main adhesive material being any one of polydimethylsiloxane glue, epoxy resin glue, synthetic silica gel; Doping black glue in the main adhesive material; The main adhesive material doped with black glue is spin-coated to the side of the conductive film layer (20) away from the circuit substrate (10) to form the photosensitive adhesive layer (30).

3. The mass transfer method of claim 1, wherein, Coating a photosensitive adhesive layer (30) on the side of the conductive film layer (20) away from the circuit substrate (10), further comprising: The thickness of the photosensitive adhesive layer (30) is less than the thickness of the die (200) by 1-2 μm.

4. The mass transfer method of claim 1, wherein, Irradiating the auxiliary transfer film (40) by laser, comprising: Determining an irradiation area; Based on the irradiation area, irradiating the auxiliary transfer film (40) by laser.

5. The mass transfer method of claim 4, wherein, Determining an irradiation area, comprising: Determining a to-be-irradiated accommodation hole (410), the to-be-irradiated accommodation hole (410) being an accommodation hole (410) that needs to accommodate the die (200); According to the area where the to-be-irradiated accommodation hole (410) is located, the irradiation area is determined.

6. The mass transfer method of claim 1, wherein, Separating the auxiliary transfer film (40) from the wafer to be transferred (100), comprising: Moving the circuit substrate (10) or the wafer to be transferred (100) in a direction perpendicular to the circuit substrate (10) to generate a gap of 3-4 μm between the auxiliary transfer film (40) and the wafer to be transferred (100).

7. The mass transfer method of claim 1, wherein, After separating the auxiliary transfer film (40) from the wafer to be transferred (100), further comprising: Stopping irradiating laser, and recovering after the auxiliary transfer film (40) cools down and shrinks; Electrically connecting the conductive film layer (20) and the die (200) remaining in the accommodation hole (410).

8. The mass transfer method of claim 7, wherein, Electrically connecting the conductive film layer (20) and the die (200) remaining in the accommodation hole (410), comprising: The conductive film layer (20) and the crystal grain (200) remaining in the accommodation hole (410) are electrically connected by any one of high temperature, high pressure, and reflux.

9. The mass transfer method of claim 1, wherein, A conductive film layer (20) is prepared on one side of a circuit substrate (10), comprising: An anisotropic conductive adhesive film is attached to one side of the circuit substrate (10); or, A metal soldering pad is prepared on one side of the circuit substrate (10).

10. A micro light emitting diode, characterized by The micro light emitting diode is prepared by the mass transfer method of any one of claims 1 to 9.

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