Micro LED unit peeling and transfer method

Abstract

The present application discloses a method for stripping and transferring a micro LED unit, including: providing a first substrate, a first surface of which is provided with a first and a second micro LED unit; providing a second substrate, a surface of which is covered with a bonding layer; setting the first surface of the first substrate relative to the surface of the bonding layer; irradiating the bonding area of ​​the first micro LED unit and the first substrate with a laser, so that the first micro LED unit is separated from the first substrate and combined with the bonding layer; after the first and second substrates move relative to each other for a certain distance in a specified direction, irradiating the bonding area of ​​the second micro LED unit and the first substrate with a laser, so that the second micro LED unit is separated from the first substrate and combined with the bonding layer, and the specified direction is a direction parallel to the surface of the bonding layer. The present application can adjust the arrangement form and spacing of the micro LED units during the laser stripping and transfer process of the micro LED units, thereby effectively simplifying the manufacturing process of the micro LED display device and reducing costs.

Description

Technical Field

[0001] The present application specifically relates to a method for peeling and transferring a micro LED unit, and belongs to the field of semiconductor technology. Background Art

[0002] Micro LED refers to Micro LED or Mini LED. Compared with traditional LED, its size is reduced from millimeter level to micro-nano level. When it is integrated into a high-density, small-size array and used in the display field, it has the advantages of high brightness, high resolution, high contrast, low energy consumption, and long service life. At the same time, it also has excellent performance in response speed and thermal stability.

[0003] To make a micro-LED array, it is first necessary to grow semiconductor materials on substrates such as sapphire, single-crystal gallium nitride, and silicon carbide, and form independent light-emitting units through semiconductor processes. The independent light-emitting units are then peeled off the substrate and transferred to a suitable transfer substrate. Among them, the main ways to peel the light-emitting units off the substrate are chemical peeling, mechanical peeling, thermal peeling, and laser peeling. Laser peeling technology mainly uses the different absorption of lasers by semiconductor materials and substrates, and the characteristics that some semiconductor materials can decompose after absorbing lasers to achieve the purpose of peeling. Compared with other methods, laser peeling technology has the characteristics of high efficiency, no pollution, little device damage, and high yield, so it can better meet the requirements of industrial production.

[0004] However, in the prior art, in the process of laser peeling the independent light-emitting units from the substrate and transferring them to the transfer base, it is usually impossible to directly adjust the arrangement and spacing of each independent light-emitting unit, and this work needs to be carried out in the subsequent process, which leads to the complication of the process and the increase of cost. Summary of the invention

[0005] The main purpose of the present application is to provide a method for peeling and transferring a micro LED unit to overcome the deficiencies in the prior art.

[0006] In order to achieve the aforementioned invention objectives, the technical solutions adopted in this application include:

[0007] One aspect of the present application provides a method for stripping and transferring a micro LED unit, comprising:

[0008] Providing a first substrate, wherein at least a first micro LED unit and a second micro LED unit are disposed on a first surface of the first substrate;

[0009] Providing a second substrate, wherein a bonding layer is covered on a surface of the second substrate;

[0010] The first surface of the first substrate is arranged opposite to the surface of the bonding layer;

[0011] Irradiating the bonding area of ​​the first micro LED unit and the first substrate with a designated light, so that the first micro LED unit is separated from the first substrate and bonded to the bonding layer;

[0012] The first substrate and the second substrate are moved relative to each other in a specified direction until the distance between the second micro LED unit and the first micro LED unit in the specified direction reaches a set value, and then the bonding area between the second micro LED unit and the first substrate is irradiated with the specified light to separate the second micro LED unit from the first substrate and bond it to the bonding layer, wherein the specified direction is a direction parallel to the surface of the bonding layer.

[0013] Another aspect of the present application provides a micro LED structure prepared by the lift-off and transfer method of the micro LED unit.

[0014] Compared with the prior art, the present application can adjust the arrangement form and spacing of micro LED units during the laser peeling and transfer process of the micro LED units, thereby effectively simplifying the manufacturing process of the micro LED display device, reducing the manufacturing difficulty of the micro LED display device, improving the production efficiency of the micro LED display device, and saving costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings in the specification, which constitute a part of the present application, are used to provide further understanding of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute improper limitations on the present application.

[0016] Figure 1 is a flow chart of a method for stripping and transferring a micro LED unit in Example 1;

[0017] Figure 2 is a schematic diagram of a first arrangement form of a micro LED array on a second substrate in Example 1;

[0018] Figure 3 is a schematic diagram of a second arrangement form of a micro LED array on a second substrate in Example 1;

[0019] Figure 4 is a schematic diagram of a third arrangement form of a micro LED array on a second substrate in Example 1;

[0020] Figure 5 is a schematic diagram of a fourth arrangement form of a micro LED array on a second substrate in Example 1;

[0021] Figure 6 is a schematic diagram of a fifth arrangement form of a micro LED array on a second substrate in Example 1;

[0022] Figure 7is a schematic diagram of a sixth arrangement form of a micro LED array on a second substrate in Example 1;

[0023] Figure 8 Flow chart of a method for stripping and transferring a micro LED unit in Example 2. DETAILED DESCRIPTION

[0024] In view of the defects of the prior art, the present application proposes a method for peeling and transferring a micro LED unit, which can achieve the adjustment of the arrangement of the micro LED array and the spacing between the micro LED units in the process of peeling the micro LED unit from the growth substrate and transferring it to a temporary substrate, thereby simplifying the micro LED manufacturing process and reducing costs.

[0025] Some embodiments of the present invention provide a method for stripping and transferring a micro LED unit, which includes:

[0026] Providing a first substrate, wherein at least a first micro LED unit and a second micro LED unit are disposed on a first surface of the first substrate;

[0027] Providing a second substrate, wherein a bonding layer is covered on a surface of the second substrate;

[0028] The first surface of the first substrate is arranged opposite to the surface of the bonding layer;

[0029] Irradiating the bonding area of ​​the first micro LED unit and the first substrate with a designated light, so that the first micro LED unit is separated from the first substrate and bonded to the bonding layer;

[0030] The first substrate and the second substrate are moved relative to each other in a specified direction until the distance between the second micro LED unit and the first micro LED unit in the specified direction reaches a set value, and then the bonding area between the second micro LED unit and the first substrate is irradiated with the specified light to separate the second micro LED unit from the first substrate and bond it to the bonding layer, wherein the specified direction is a direction parallel to the surface of the bonding layer.

[0031] Furthermore, when the first surface of the first substrate and the surface of the bonding layer are arranged opposite to each other, ideally, the first surface of the first substrate and the surface of the bonding layer should be parallel to each other. Therefore, the specified direction is also an arbitrary direction parallel to the first surface of the first substrate.

[0032] Furthermore, the first substrate and the second substrate may move relative to each other in a specified direction in various forms, such as relative movement along a linear motion trajectory or relative movement along a curved motion trajectory. Exemplarily, the first substrate and the second substrate may rotate relative to each other in a clockwise or counterclockwise direction.

[0033] Furthermore, if the surface of the bonding layer is defined as a two-dimensional plane based on an XY coordinate system, the specified direction may be a direction parallel to the X-axis, Y-axis, or any other straight line or curve in the XY plane. In this way, by simply adjusting the direction and distance of the relative movement between the first substrate and the second substrate, the arrangement and spacing of the second micro LED unit and the first micro LED unit on the bonding layer can be quickly and accurately adjusted.

[0034] In one embodiment, the micro LED unit peeling and transfer method specifically includes: allowing the designated light to penetrate into the first substrate from the second surface of the first substrate and irradiate a bonding area between the first micro LED unit or the second micro LED unit and the first substrate.

[0035] The first substrate may be selected from a sapphire substrate, a glass substrate or other light-transmitting substrate, but is not limited thereto. The first micro LED unit and the second micro LED unit may be formed by directly processing a semiconductor material layer grown on the first substrate, or may be bonded to the first substrate by bonding or the like.

[0036] Furthermore, the first micro LED unit and the second micro LED unit may include a Micro LED chip or a Mini LED chip based on III-V group compounds such as GaN, AlGAN, InN, AlInGaN, etc., but are not limited thereto.

[0037] Furthermore, at least part of the material in the bonding area between the first micro LED unit or the second micro LED unit and the first substrate can be decomposed under the irradiation of the specified light, so that the first micro LED unit or the second micro LED unit is separated. The wavelength, power and irradiation time of the specified light can be determined according to actual conditions.

[0038] Exemplarily, part of the material of the bonding area between the first micro LED unit or the second micro LED unit and the first substrate is GaN, which can be decomposed into Ga and nitrogen under laser irradiation of a certain power, thereby releasing the connection between the first micro LED unit or the second micro LED unit and the first substrate, that is, achieving laser peeling of the first micro LED unit or the second micro LED unit.

[0039] In one embodiment, the micro LED unit peeling and transfer method specifically includes: setting a mask on the second surface of the first substrate, and allowing the specified light to pass through the window on the mask and then irradiate the bonding area between the first micro LED unit or the second micro LED unit and the first substrate until the first micro LED unit or the second micro LED unit is separated from the first substrate.

[0040] The mask may be made of inorganic materials such as metal or organic materials such as black resin or composite materials thereof, and a selected area of ​​the mask is removed or made of a transparent material, so as to form a window on the mask for the specified light to pass through. The size and position of the window correspond to the size of the micro LED unit to be peeled off and the distribution position on the first substrate.

[0041] By using the mask to assist in the stripping of the micro LED unit, on the one hand, the accuracy and precision of the stripping can be improved and the stripping effect can be optimized; on the other hand, damage to the first substrate or the remaining micro LED units on the first substrate caused by the laser during the stripping process can be prevented.

[0042] In one embodiment, the micro-LED unit peeling and transfer method specifically includes: shaping the designated light so that when the designated light irradiates the bonding area between the first micro-LED unit or the second micro-LED unit and the first substrate, the ratio of the area of ​​the light spot formed to the area of ​​the first micro-LED unit or the second micro-LED unit reaches a certain value, for example, preferably 0.5 to 2:1, so that the first micro-LED unit or the second micro-LED unit is separated from the first substrate. The operation of shaping the designated light can be achieved by means of a lens, a lens assembly or other optical equipment known in the art.

[0043] By using shaped specified light to perform the stripping operation of the micro LED unit, the cost is lower and the operation is simpler than using a mask to assist in stripping.

[0044] Furthermore, the micro LED unit peeling and transfer method specifically includes: focusing the designated light on the bonding area between the first micro LED unit or the second micro LED unit and the first substrate, thereby separating the first micro LED unit or the second micro LED unit from the first substrate.

[0045] In one embodiment, the micro-LED unit peeling and transfer method specifically includes: irradiating the bonding area between the first micro-LED unit or the second micro-LED unit and the first substrate with the specified light, so that at least part of the material in the bonding area decomposes and forms a gas with a predetermined pressure, and the first micro-LED unit or the second micro-LED unit is separated from the first substrate at least under the pressure of the gas and transferred to the bonding layer.

[0046] In one embodiment, the micro-LED unit peeling and transfer method specifically includes: irradiating the bonding area of ​​the first micro-LED unit or the second micro-LED unit and the first substrate with the specified light under vacuum conditions, so that the first micro-LED unit or the second micro-LED unit is separated from the first substrate and bonded to the bonding layer. By performing these operations in a vacuum environment, it is possible to prevent the micro-LED unit from flipping and drifting due to air resistance when it falls onto the bonding layer. In addition, the use of a vacuum environment can also eliminate the interference of factors such as air refraction on laser peeling.

[0047] In one embodiment, the micro LED unit peeling and transfer method specifically includes: when the first surface of the first substrate is arranged opposite to the surface of the bonding layer, a gap is left between the first micro LED unit or the second micro LED unit and the bonding layer. This method can avoid the operation of bonding the first substrate to the second substrate.

[0048] Furthermore, the gap should have a certain width, for example, greater than twice the thickness of the first micro LED unit or the second micro LED unit, so as to prevent the first micro LED unit bonded to the bonding layer from colliding with the second micro LED unit bonded to the first substrate during the relative movement of the first substrate and the second substrate along a specified direction. However, the width is less than a threshold value, so that the micro LED unit peeled off from the first substrate can quickly and smoothly contact and bond with the bonding layer, avoiding defects such as reduced transfer efficiency, micro LED unit flipping or deviation from a predetermined bonding position caused by excessive running distance of the micro LED unit. Preferably, the width of the gap is 1 to 50 μm.

[0049] Furthermore, the first substrate is disposed above the second substrate. Thus, when the micro LED unit is peeled off from the first substrate, the gas pressure generated by the decomposition of the material in the bonding area between the micro LED unit and the first substrate and the gravity of the micro LED unit itself can be utilized to enable the micro LED unit to more quickly detach from the first substrate and contact the bonding layer. Preferably, the first substrate and the second substrate are in the same vacuum environment to prevent the micro LED unit from flipping and drifting due to air resistance during the transfer from the first substrate to the bonding layer.

[0050] In one embodiment, the first micro LED unit or the second micro LED unit includes a Micro LED or a Mini LED.

[0051] In one embodiment, the designated light comprises laser light.

[0052] In one embodiment, the first micro LED unit or the second micro LED unit is adhesively bonded to a bonding layer.

[0053] In one embodiment, the material of the bonding layer includes polyimide, polyacrylic resin, epoxy resin, polydimethylsiloxane or wax, but is not limited thereto.

[0054] In one embodiment, the bonding layer has a thickness of 1-100 μm.

[0055] Some embodiments of the present invention provide a method for stripping and transferring a micro LED unit, including:

[0056] At least a first micro LED unit and a second micro LED unit are formed on a first surface of the first substrate, wherein the first micro LED unit and the second micro LED unit have a first distance in a specified direction;

[0057] forming a bonding layer on a surface of the second substrate;

[0058] The first surface of the first substrate is arranged opposite to the surface of the bonding layer, and a gap is left between the first micro LED unit or the second micro LED unit and the bonding layer;

[0059] Transmitting a laser into the first substrate from the second surface of the first substrate and irradiating a first bonding area between the first micro LED unit and the first substrate until at least a portion of the material in the first bonding area is decomposed, thereby separating the first micro LED unit from the first substrate and bonding with the bonding layer, wherein the second surface of the first substrate is disposed opposite to the first surface;

[0060] Then, the first substrate and the second substrate are relatively moved in a specified direction until the second micro LED unit has a second distance from the first micro LED unit in the specified direction, and the second distance is greater than or less than the first distance, and then a second bonding area between the second micro LED unit and the first substrate is irradiated with a laser until at least part of the material in the second bonding area is decomposed, so that the second micro LED unit is separated from the first substrate and bonded to the bonding layer;

[0061] Wherein, the specified direction is a direction parallel to the surface of the bonding layer.

[0062] The wavelength, power, irradiation time, etc. of the laser can be determined according to the size and material of the bonding area between each micro LED unit and the first substrate. Exemplarily, the laser is an ultraviolet laser, and the bonding area between each micro LED unit and the first substrate contains III-V compounds such as GaN, which can be decomposed after absorbing the ultraviolet laser.

[0063] The present application can realize the quick and accurate peeling of micro LED units, and can directly adjust the arrangement form and distance of micro LED units during the peeling and transfer process of micro LED units. The operation is simple and the accuracy is high. Therefore, it is helpful to simplify the manufacturing process of micro LED display devices, reduce the manufacturing difficulty and cost, and also help to improve the yield and quality of micro LED display devices.

[0064] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0065] For example, when describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional view showing the device structure will not be partially enlarged according to the general scale, and the schematic view is only an example, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional space dimensions of length, width and depth should be included.

[0066] For ease of description, spatially relative terms such as "under", "below", "below", "below", "above", "on", etc. may be used herein to describe the relationship of one element or feature shown in the drawings to other elements or features. It will be understood that these spatially relative terms are intended to encompass other orientations of the device in use or operation in addition to the orientation depicted in the drawings. In addition, when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present.

[0067] In the context of the present application, a structure in which a first feature is described as being "above" a second feature may include embodiments in which the first and second features are in direct contact, and may also include embodiments in which additional features are formed between the first and second features, such that the first and second features may not be in direct contact.

[0068] It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and therefore the illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0069] Example 1 Please refer to Figure 1 The present embodiment provides a method for stripping and transferring a micro LED unit, comprising the following steps:

[0070] S1. Provide a sapphire substrate 10 (defined as a first substrate) having a plurality of micro LED units formed on the front side (defined as a first side 101), and define a portion of the micro LED units as first micro LED units 111, and another portion of the micro LED units as second micro LED units 112. The diameter of the sapphire substrate may be 2, 4 or 6 inches. The spacing between adjacent micro LED units is W1, where W1 ≥ 0. Each micro LED unit may include one or more Micro LED chips or Mini LED chips. These LED chips may be GaN-based LED chips, and the bonding area between each chip and the sapphire substrate 10 may be its GaN buffer layer. The sapphire substrate 10 may also be replaced with a material that is transparent to ultraviolet light, such as glass.

[0071] S2. A temporary bonding layer 13 (referred to as "bonding layer") is formed on the front side of the temporary substrate 12 (which may be defined as the second substrate) by at least spin coating, scraping, spraying or dry film transfer or other methods known in the art. The bonding layer may be made of a material selected from, but not limited to, a combination of one or more of polyimide, polyacrylic resin, epoxy resin, polydimethylsiloxane and wax, and its thickness may be between 1 and 100 μm.

[0072] S3. Arrange the sapphire substrate 10 and the temporary substrate 12 in the horizontal direction, and make the sapphire substrate 10 above the temporary substrate 12, and then flip the sapphire substrate 10 vertically, so that the multiple micro LED units and the bonding layer 13 are arranged opposite to each other, and a certain gap is left between the micro LED units and the bonding layer 13, and the width of the gap is preferably 1 to 50 μm.

[0073] S4. A mask plate 14 is disposed on the back side (which can be defined as the second side 102) of the sapphire substrate 10. The mask plate 14 is provided with a plurality of windows for light to pass through. The shape and area of ​​each window match the shape and size of the bonding area between the corresponding micro LED unit to be peeled off and the sapphire substrate.

[0074] S5. Set a window on the mask 14 that matches the first micro LED unit 111 at a position corresponding to the first micro LED unit 111, and focus the ultraviolet laser 15 through the window on the bonding area between the first micro LED unit 111 and the sapphire substrate, so that the GaN in the bonding area is decomposed into Ga and nitrogen, and then the first micro LED unit 111 is separated from the sapphire substrate under nitrogen pressure, that is, peeled off from the sapphire substrate, and then transferred to the bonding layer 13 under the action of nitrogen pressure and its own gravity, and bonded to the bonding layer 13.

[0075] S6. Make the sapphire substrate 10 and the temporary substrate 12 move relative to each other along a horizontal straight line. The horizontal straight line can be considered as the X-axis in an XY plane parallel to the surface of the bonding layer 13. The distance of the relative movement is L, L>0, and the window on the mask 14 that matches the second micro LED unit 112 is set at the corresponding position of the second micro LED unit 111.

[0076] S7. After passing an ultraviolet laser through the window, focus it on the bonding area between the second micro LED unit 111 and the sapphire substrate, so that the GaN in the bonding area is decomposed into Ga and nitrogen, and then the second micro LED unit 111 is separated from the sapphire substrate under nitrogen pressure, that is, peeled off from the sapphire substrate, and then transferred to the bonding layer 13 under the action of nitrogen pressure and its own gravity, and bonded to the bonding layer 13. In this way, the spacing between adjacent micro LED units transferred to the temporary substrate 12 can be adjusted to w2, w2 = 2*W1-L. In this embodiment, the aforementioned relative movement is to make the sapphire substrate 10 and the temporary substrate 12 move away from each other along the aforementioned X-axis, so W2>W1. However, in some cases, the aforementioned relative movement can also be to make the sapphire substrate 10 and the temporary substrate 12 approach each other along the aforementioned X-axis, so w2<w1. By adjusting the value of L, the spacing between each micro LED unit can be conveniently, quickly and accurately adjusted to any value when multiple micro LED units are peeled off and transferred to the temporary substrate 12.

[0077] Furthermore, the aforementioned relative movement may also include causing the sapphire substrate 10 and the temporary substrate 12 to move toward or away from each other along the Y-axis in the aforementioned XY plane, or to move along any straight line different from the X and Y axes, or to rotate clockwise or counterclockwise relative to each other by a certain angle in the aforementioned XY plane, so that the arrangement of the multiple micro LED units on the temporary substrate and the distance between them meet the set requirements.

[0078] For example, after the micro LED units are peeled off and transferred using the method of this embodiment, some arrangements of the micro LED units on the temporary substrate are as follows: Figure 2-Figure 7 Further, in Figure 2 In the first arrangement shown, the arrangement directions of the multiple micro LED units are consistent and parallel to each other on the horizontal plane, and the distance between adjacent micro LED units does not exceed 5 μm. Figure 3 In the second arrangement shown, the arrangement directions of the multiple micro LED units are consistent, but the positions are staggered, and the distance between adjacent micro LED units exceeds 5 μm. Figure 4 In the third arrangement shown, the arrangement directions of the multiple micro LED units are inconsistent, and the positions are staggered, and the distance between adjacent micro LED units exceeds 5 μm. Figure 5In the fourth arrangement shown, the number of micro LED units contained in a single repeating unit is a multiple of 3, for example, 6, and these micro LED units are arranged in an array, and the position accuracy of each micro LED unit when transferred from the sapphire substrate 10 to the bonding layer 13 is controlled within 5 μm. Figure 6 In the fifth arrangement shown, the number of micro LED units contained in a single repeating unit is a multiple of 3, for example, 9, and these micro LED units are arranged in an array, and the position accuracy of each micro LED unit when transferred from the sapphire substrate 10 to the bonding layer 13 is controlled within 5 μm. Figure 7 In the sixth arrangement shown, the number of micro LED units contained in a single repeating unit is a multiple of 3, such as 9, but these micro LED units do not have an array relationship.

[0079] In this embodiment, the execution order of the aforementioned steps S1 and S2 can also be exchanged. Also, the aforementioned steps S5 and S7 are preferably performed under vacuum conditions.

[0080] In this embodiment, there can be only one window set on the aforementioned mask 14, and in steps S5 and S6, the mask 14 can be moved to make the window reach different workstations respectively, so that the laser can pass through the window and focus on the bonding area between the first micro LED unit and the sapphire substrate, and the bonding area between the second micro LED unit and the sapphire substrate, respectively, to achieve the peeling of the first micro LED unit and the second micro LED unit.

[0081] Example 2 Please refer to Figure 8 The present embodiment provides a method for stripping and transferring a micro LED array which is basically the same as that of the first embodiment, except that step S4 in the first embodiment is omitted, and a mask is not used to assist in stripping the micro LED unit. Instead, the laser is shaped so that the shaped laser 16 can be focused into a smaller light spot at the bonding area between the first micro LED unit and the sapphire substrate and the bonding area between the second micro LED unit and the sapphire substrate. Preferably, the ratio of the area of ​​the light spot to the area of ​​the micro LED unit is 0.5 to 2, so that the target micro LED unit can be stripped more accurately, avoiding damage to other micro LED units and improving the energy efficiency of the laser. Compared with the first embodiment, the method of the present embodiment is less expensive.

[0082] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for stripping and transferring a micro LED unit, characterized in that: include: Providing a first substrate, wherein the first substrate has a first surface and a second surface disposed opposite to each other, and the first surface is provided with at least a first micro LED unit and a second micro LED unit; Providing a second substrate, wherein a bonding layer is covered on a surface of the second substrate; The first substrate is disposed above the second substrate, and the first surface of the first substrate is disposed opposite to the surface of the bonding layer, and a gap is left between the first micro LED unit or the second micro LED unit and the bonding layer, and the width of the gap is 1-50 μm; In a vacuum environment and without using a mask to assist stripping, the shaped designated light is transmitted into the first substrate from the second surface of the first substrate, and irradiates the bonding area of ​​the first micro LED unit and the first substrate, so that the first micro LED unit is separated from the first substrate and bonded to the bonding layer; The first substrate and the second substrate are relatively moved in a specified direction until the distance between the second micro LED unit and the first micro LED unit in the specified direction reaches a set value, and then the shaped specified light is transmitted from the second surface of the first substrate into the first substrate in the vacuum environment, and irradiates the bonding area of ​​the second micro LED unit and the first substrate, so that the second micro LED unit is separated from the first substrate and bonded to the bonding layer, and the specified direction is a direction parallel to the surface of the bonding layer; Among them, when the shaped designated light is irradiated to the bonding area between the first micro LED unit or the second micro LED unit and the first substrate, the ratio of the area of ​​the formed light spot to the area of ​​the first micro LED unit or the second micro LED unit is 0.5~2:1, and it can decompose at least part of the material in the bonding area and form a gas with a predetermined pressure, so that the first micro LED unit or the second micro LED unit is separated from the first substrate under the pressure of the gas and the gravity of the micro LED unit itself, and transferred to the bonding layer.

2. The method for peeling and transferring a micro LED unit according to claim 1, wherein: The first micro LED unit or the second micro LED unit includes a Micro LED or a Mini LED.

3. The method for peeling and transferring a micro LED unit according to claim 1, wherein: The material of the bonding layer includes polyimide, polyacrylic resin, epoxy resin, polydimethylsiloxane or wax.

4. The method for peeling and transferring a micro LED unit according to claim 1, wherein: The thickness of the bonding layer is 1-100 μm.

5. The method for peeling and transferring a micro LED unit according to claim 1, wherein: The designated light is laser.

6. The method for stripping and transferring a micro LED unit according to claim 5, wherein: Specifically include: After the first micro LED unit is separated from the first substrate and combined with the bonding layer, the first substrate and the second substrate are moved relative to each other in a specified direction until the second micro LED unit has a second distance with the first micro LED unit in the specified direction, and the second distance is greater than or less than the first distance, and then the laser is used to irradiate a second bonding area between the second micro LED unit and the first substrate until at least part of the material in the second bonding area is decomposed, thereby separating the second micro LED unit from the first substrate and combining with the bonding layer.

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