CN114944442A - Laser projection proximity type MicroLED huge transfer transposition, method and system - Google Patents

Abstract

The invention belongs to the technical field of semiconductors, and discloses a laser projection proximity type mass transfer device, a forming method and a laser projection system. The device comprises a support layer, a dynamic release layer and an adhesive layer, wherein the support layer is a base layer, the dynamic release layer is arranged on the base layer, the adhesive layer is arranged on the dynamic release layer, and the In contact with the MicroLED to be transferred, when the laser passes through the support layer and irradiates the dynamic release layer, the dynamic release layer undergoes ablation or a phase change, thereby bulging and causing the viscous layer to also bubble, thereby The contact with the to-be-transferred MicroLED is reduced, and the transfer device and the to-be-transferred MicroLED are peeled off. Through the present invention, the problem of mass transfer of MicroLED is solved.

Description

A laser projection proximity type MicroLED mass transfer transposition, method and system

technical field

The invention belongs to the technical field of semiconductors, and more particularly, relates to a laser projection proximity type MicroLED mass transfer transposition, method and system.

Background technique

Although MicroLED has many advantages and bright application prospects, the key difficulty lies in how to transfer a large number of micro-scale MicroLEDs to display circuit substrates. The main reason is that as the size of MicroLED gradually decreases (≤50μm), the decay rate of gravity is faster than that of van der Waals force or electrostatic attraction, resulting in no effective range for the pick-up method of robotic hands and vacuum adsorption (limit size ~ 80μm), and the transfer efficiency is slow ( ~25,000/hour), so it is difficult to meet the transfer reliability and efficiency requirements of micro-scale chips, so Mass Transfer technology also came into being. Mass transfer technology requires selective batch transfer of micron-sized MicroLEDs from native sapphire substrates to circuit substrates. Due to the very small size of MicroLEDs, and mass transfer technology requires very high yield (99.9999%), efficiency and The transfer accuracy (±5μm), so the mass transfer technology has also become the biggest challenge in the MicroLED display research and development process, hindering the development of MicroLED.

The method of transferring MicroLED mainly relies on the sticky stamp method and the direct physical contact of the transfer chip, and the transfer is completed by controlling the stickiness of the stamp and the chip. Although it can be transferred in large quantities, it cannot be selectively transferred. Electrostatic adsorption needs to be stamped on a specific magnetic MicroLED to achieve transfer work, which has certain limitations. Laser non-contact transfer technology is driven by laser to achieve non-contact selective processing, and realizes the array and batch transfer of MicroLEDs in the form of patterned laser spots. Due to the unique advantages of laser processing, such as rapid processing, selectivity, and localization of affected areas, it can efficiently realize the transfer of MicroLED arrays and batches, and is expected to be applied to the manufacture of ultra-large, high-resolution Micro LED displays.

However, the current laser non-contact transfer technology still has certain limitations. For example, the gas shock-laser forward transfer technology needs to ablate the sacrificial layer in the seal and generate shock waves to achieve chip transfer, but because: 1) the peeling of the chip is not completely symmetrical, which affects the flight trajectory of the chip; 2) this kind of shock wave often The propagation speed is faster than the drop speed of the chip, so a shock wave will be generated to bounce back to the receiving substrate, affecting the stability of the chip drop point. The above two reasons directly affect the transfer accuracy of the chip. Bubble-laser forward transfer technology has received extensive attention due to its good dimensional compatibility and process feasibility. This process mainly uses the laser to interact with the power release layer, vaporize the power release layer, and form bubbles to promote chip transfer. . In this process, since the shock wave is surrounded by the DRL layer, the impact of the shock wave on the transfer of the chip is greatly reduced. still affects the transfer accuracy. For example, when transferring a 670×670×50μm chip, under the transfer pitch of 195μm, there is still an offset, and the mean, median and standard deviation are 61.2μm, 50.0μm and 46.3μm, respectively. In addition, the magnetic field is used in the prior art. It uses a magnetic field to magnetize the laser-induced falling chip, and pulls it to the target position to achieve autonomous positioning. Although this method can further improve the accuracy, it cannot easily achieve a tighter array arrangement of MicroLEDs on the receiving substrate, and the chip requires a magnetization layer, so it has certain limitations.

SUMMARY OF THE INVENTION

In view of the above defects or improvement needs of the prior art, the present invention provides a laser projection proximity MicroLED mass transfer transposition, method and system to solve the problem of low precision in MicroLED mass transfer.

In order to achieve the above object, according to one aspect of the present invention, a laser projection proximity mass transfer device is provided, the device includes a support layer, a dynamic release layer and an adhesive layer, wherein,

The support layer is a base layer, the dynamic release layer is disposed on the base layer, and the adhesive layer is disposed on the dynamic release layer for contact with the MicroLED to be transferred. When the laser passes through the support layer When irradiated on the dynamic release layer, the dynamic release layer undergoes ablation or a phase change, so as to bulge and make the viscous layer also bubble, thereby reducing the contact with the MicroLED to be transferred and realizing the transfer and Stripping of the MicroLED to be transferred.

Further preferably, the material used for the dynamic release layer is one of polyimide, GaN film, triazene polymer, gold and titanium.

Further preferably, the thickness of the dynamic release layer is 5 μm˜15 μm.

Further preferably, the adhesive layer is a viscoelastic material, such as polydimethylsiloxane or epoxy resin.

Further preferably, the thickness of the adhesive layer is 30 μm˜40 μm.

Further preferably, the material of the support layer is sapphire or quartz.

Further preferably, the thickness of the support layer is 500 μm˜1000 μm.

According to another aspect of the present invention, there is provided a laser projection proximity mass transfer method described above, the method comprising the following steps:

S1 sets the mass transfer device above the MicroLED to be transferred, and corresponds one by one;

S2 uses a laser to irradiate the mass transfer device, and the laser passes through the support layer and irradiates the dynamic release layer, so that the dynamic release layer is ablated or phase-change bubbling occurs, and the adhesive layer of the mass transfer device and the MicroLED to be transferred are The interface contact area is reduced;

The S3 mass transfer device bubbling to produce a rebound, allowing the MicroLED to be completely peeled from the stamp and successfully transferred to the receiving substrate.

According to another aspect of the present invention, there is provided a system for laser projection by the above-mentioned laser projection proximity mass transfer device, characterized in that the system includes a light source, an attenuator, a telephoto unit, a light homogenizer, Spot projection unit and motion platform, where:

The attenuator is arranged in front of the light source to adjust the output energy of the laser light emitted by the light source; the telephoto unit is arranged behind the attenuator to expand the light spot from the attenuator. beam and shaping; the light homogenizer is arranged behind the telephoto unit, and is used to intercept a section of light beam with stable wavelength from the light from the telephoto unit; the spot projection unit is arranged at the back of the light homogenizer The rear is used for patterning and focusing the light from the homogenizer, and the moving platform is arranged below the spot projection unit for placing the above-mentioned laser projection proximity mass transfer device.

Further preferably, the system further includes a reflecting mirror, and between the attenuator and the telephoto unit, and between the light homogenizer and the light spot projection unit, a reflecting mirror is arranged for changing the direction of the light path.

In general, compared with the prior art, the above technical solutions conceived by the present invention have the following beneficial effects:

1. The laser mass transfer device provided by the present invention can not only rapidly adjust the bubbling height of the transfer device and the interface viscosity between the chip and the transfer device through the laser, but also match the micro-spacing between the MicroLED and the receiving substrate, so that the MicroLED chip and the receiving substrate can be adjusted. From the original non-contact to weak contact, high-precision and high-reliability transfer is realized, avoiding the influence of laser shock wave, chip flying, asymmetric peeling, chip rebounding on the receiving substrate, chip deflection and other factors on the transfer accuracy, which is significantly improved. improved MicroLED transfer accuracy and efficiency;

2. The proximity laser mass transfer of the present invention reduces the flatness requirements of the transfer device and the size of the receiving substrate. Since the transfer device does not need to be in complete contact with the receiving substrate during the release process, the error of the flatness affects the transfer success rate. The influence of the transfer device is greatly reduced, so as to ensure the transfer accuracy, and at the same time, the non-contact is turned into a weak contact in the later stage. Since the transfer device presents a hemispherical or bubbling shape at this time, its conformality is often better than that of the plane transfer device, so it greatly reduces the impact on the transfer device. Receive base size requirements;

3. The present invention adopts a laser projection system, which can project the laser beam into a plurality of single-beam lasers through the mask plate to realize parallel transfer. At the same time, the projection method is adopted to make the mask hole processing larger than the required spot size year-on-year. m times, greatly reduces the processing difficulty of the mask, improves the spot resolution, further reduces the laser diffraction effect, and can further homogenize the spot shape, reduce the influence of uneven spot energy and shape on the transfer accuracy, thereby greatly improving the giant Volume transfer accuracy;

4. The transfer device prepared by the present invention has a simple process, does not require additional complex process means such as photolithography, secondary mold injection, bonding, etc., which greatly reduces the complexity of the massive transfer operation and improves the transfer rate.

Description of drawings

1 is a schematic structural diagram of a laser projection proximity mass transfer device constructed according to a preferred embodiment of the present invention;

Fig. 2 is the relation diagram of the dynamic release layer constructed according to the preferred embodiment of the present invention and bubbling height;

3 is a schematic diagram of different distances between a transfer device constructed according to a preferred embodiment of the present invention and a receiving substrate, wherein (a) is a schematic diagram of an excessively small distance; (b) is a schematic diagram of an excessively large distance;

4 is a schematic flow chart of the working principle of the transfer device constructed according to the preferred embodiment of the present invention;

5 is a schematic structural diagram of a laser projection system constructed according to a preferred embodiment of the present invention;

6 is a simplified schematic diagram of a laser projection system constructed in accordance with a preferred embodiment of the present invention;

FIG. 7 is a schematic diagram of an array reduced size of a laser projection system constructed according to a preferred embodiment of the present invention;

8 is a schematic diagram of an array light spot constructed according to a preferred embodiment of the present invention on a transfer device;

FIG. 9 is an overall process flow diagram of transferring the MicroLED constructed according to the preferred embodiment of the present invention.

Throughout the drawings, the same reference numbers are used to refer to the same elements or structures, wherein:

10-transfer device, 11-support layer, 12-dynamic release layer, 13-adhesive layer, 20-MicroLED, 30-receiving substrate, 40-laser, 41-light source, 42-attenuator, 43-telephoto unit, 44 -Diffuser, 45-Spot Projection Unit, 451-Spot Patterning Module, 452-Spot Scaling and Focusing Module, 453-Reticle, 50-Peel Force, 60-Intermediate Carrier Substrate, 70-Native Substrate, 80- UV laser, 90-motion platform.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

As shown in FIG. 1, the laser projection proximity mass transfer device includes a support layer 11, a dynamic release layer 12 and an adhesive layer 13, wherein the support layer is a base layer, and the dynamic release layer is disposed on the base layer on the dynamic release layer, the adhesive layer is arranged on the dynamic release layer for contact with the MicroLED to be transferred. When the laser passes through the support layer and irradiates on the dynamic release layer, the dynamic release layer undergoes ablation or phase change , so as to bulge and make the adhesive layer also bubble, thereby reducing the contact with the MicroLED to be transferred, and realizing the peeling of the transfer device from the MicroLED to be transferred.

Further preferably, the material used for the dynamic release layer is one of polyimide, GaN thin film, triazene polymer, gold and titanium. The above-mentioned materials are easily photothermally reacted with the laser (~800°C), and ablation generates gases such as co and co ₂ , which inflate and make the viscous layer also bubbling.

Further preferably, the thickness of the dynamic release layer is 5 μm˜15 μm. When the film is too thin at 0-4μm, when the dynamic release layer undergoes ablation or phase transition, it is easy to cause film damage and fracture, while at >15μm, the dynamic release layer is too thick, resulting in excessive bending stiffness, so it is not easy to produce bulging Bubble.

Further preferably, the adhesive layer is a viscoelastic material, such as polydimethylsiloxane or epoxy resin. The above materials are easy to prepare and can provide adhesion strengths of 0-50 kPa at the same time.

Further preferably, the thickness of the adhesive layer is 30 μm˜40 μm. Further preferably, the material of the support layer is sapphire or quartz. Sapphire or quartz generally does not absorb laser light, so that the laser light can penetrate, so that the laser light directly acts on the dynamic release layer.

Further preferably, the thickness of the support layer is 500 μm˜1000 μm. The thickness of the support layer cannot be affected by the deformation of the dynamic release layer due to ablation or phase change.

The bubble height produced by the laser-induced transfer device can be controlled by controlling the laser energy and the number of irradiations.

In the transfer device 10 with the MicroLED 20 in FIG. 1, under the action of the laser 40, the dynamic release layer 12 in the transfer device 10 is ablated and vaporized to form bubbles, and the highest height of the bubbles at the final equilibrium is h1 (8～ 3000 μm). As shown in FIG. 2 , under the action of the laser 40 , the bubbling change data of the transfer device 10 is illustrated. According to different dynamic release layers 12 , the final bubbling height is different, but there are high rebound areas and bubbling in the rear area. A plateau where the height gradually plateaus.

The patterned laser array spot formed by the laser projection through the optical mask precisely acts on the transfer device and produces "bubble"; before the transfer, the MicroLED adhered to the transfer device is separated from the receiving substrate by a small distance (for example, 8 ~500μm), the bubbling height is close to the distance between the MicroLED and the substrate (for example, 10-500μm), so that the chip and the receiving substrate can be transferred from the original non-contact to weak contact, achieving high-precision and high-reliability transfer. LaserPPT has significant advantages: 1) Different lasers can be selected according to the working principle of the laser and the transfer device, which has very high flexibility; 2) The laser projection type optical path system is used, that is, the optical system is used to homogenize the Gaussian distributed laser into Flat-top beam, and in order to realize array formation, the pattern on the mask plate is reduced by m times (m is generally 5-10) by optical projection, focused and aligned with the chip to be transferred on the transfer device, and radiated on the dynamic release layer. On the other hand, this optical projection method can effectively improve the resolution of laser radiation, reduce the influence of diffraction effect, Gaussian spot unevenness, etc., and greatly reduce the processing difficulty of the mask plate; 3) It can take into account the contact type of the transfer device. The high-precision advantage of transfer printing and the high efficiency of laser forward transfer avoid the influence of factors such as laser shock wave, chip flying, asymmetric peeling, chip rebound on the receiving substrate, etc. on the transfer accuracy, which significantly improves the transfer accuracy and efficiency of MicroLED .

Figure 3 is a schematic diagram of an example of the transfer result that may occur when the initial distance between the transfer device with the chip and the receiving substrate is not appropriate in the laser projection proximity mass transfer process. Small, and when the laser action is intense, there may be a collision problem with the MicroLED 20. In (b) of FIG. 3 , because the distance is too large, there may be a situation where the MicroLED 20 does not contact the receiving substrate 30 . It is also possible that if the spacing is too small, the viscoelastic effect will be brought about because the rebound speed is too fast. The maintaining distance can be 8-3000μm, specifically, it is necessary to ensure that the distance is between the ablation gas in the dynamic release layer, so that the bubbling height gradually tends to the height of the equilibrium stage and the highest bubbling height in the equilibrium stage, so as to avoid the ablation gas in the early stage. The laser action is strongly bubbling, causing velocity shocks and viscoelastic effects with the receiving substrate.

FIG. 4 is a working flow chart of the laser projection proximity mass transfer method proposed by the present invention. First, the excitation transfer device 10 with the MicroLED 20 and the receiving substrate 30 maintain a small distance h ₂ . The h ₂ distance needs to be in the dynamic release layer of the ablation gas so that the bubble height gradually tends to the height of the equilibrium stage and the height of the equilibrium stage. between the highest bubbling height _h1 ; secondly, under the irradiation of the laser 40, the dynamic release layer 12 in the transfer device 10 is ablated and vaporized to form bubbling, the interface contact area between the transfer device 10 and the MicroLED 20 is reduced, and the adhesion At the same time, the height of the bubbling h ₂ of the transfer device 10 can reach h ₁ , so that the MicroLED 20 is in weak contact with the receiving substrate 30; then, the peeling force 50 is slowly applied on the support layer, and the transfer device is lifted; finally, make The MicroLED 20 is gradually layered with the transfer device 10 and finally successfully transferred.

FIG. 5 is a schematic structural diagram of a laser projection system. The system includes a light source, an attenuator 42, a telephoto unit 43, a diffuser 44, a spot projection unit 45 and a motion platform 90, wherein: the attenuator is arranged in front of the light source and is used to adjust the light emitted by the light source. The output energy of the laser; the telephoto unit 43 is arranged behind the attenuator for beam expansion and shaping of the light spot from the attenuator; the light homogenizer is arranged behind the telephoto unit 43, For intercepting a wavelength-stabilized light beam from the light from the telephoto unit; the spot projection unit 45 is arranged behind the light homogenizer 44 for patterning the light from the light homogenizer and focusing, the motion platform 90 is arranged below the spot projection unit 45 for placing the above-mentioned laser projection proximity mass transfer device.

The system also includes a reflector, and between the attenuator 42 and the telephoto unit 43, and between the light homogenizer 44 and the spot projection unit 45, a reflector is arranged for changing the direction of the light path.

Figure 6 is a simplified schematic of a laser projection system. The laser light source 41 emits a light source, and the light spot with uneven energy is homogenized by the light homogenizer 44, and further passes through the light spot patterning module 451 system, so that part of the light spot is patterned and propagated to the light spot scaling and focusing module 452, so that the original mask is The image on the stencil 453 is reduced by a factor of 4 or 5, and after being focused and aligned with the desired transfer position on the transfer device, the array light spot acts on the transfer device 10 .

FIG. 7 is a schematic diagram illustrating the size of the arrayed light spot reduced by 4 or 5 times. The uniformized laser light source 41 forms an array or patterned spot through the mask 453 . At this time, the size of the pattern is 5 times, which is reduced to 1 times through the spot scaling and focusing module 452 on the support layer 11 of the transfer device 10 .

FIG. 8 is a three-dimensional schematic diagram of an arrayed light spot acting on a transfer device. Taking four laser beams as an example, the four laser beams are respectively irradiated to the corresponding positions of the transfer device 10, and the dynamic release layer 12 is vaporized and bubbling.

FIG. 7 is a schematic diagram of the process of transferring the MicroLED from the sapphire substrate to the intermediate carrier substrate 60. The implementation of the method generally needs to include the following steps:

Step 1: Press the MicroLED 20 onto the intermediate carrier substrate 60 . The ultraviolet laser 80 is used to pass through the native substrate 70 and irradiate the interface between the MicroLED 20 and the native substrate 70 . Since the substrate of MicroLED 20 is made of gallium nitride material, gallium nitride can absorb ultraviolet laser light and thermally decompose to form liquid gallium and nitrogen gas. Therefore, the adhesion strength of the interface between the MicroLED 20 and the native substrate 70 is significantly reduced after being irradiated by the laser, and the MicroLED 20 can be separated from the native substrate 70 .

Step 2: Complete the transfer of the MicroLED 20 to the receiving substrate 30 as a whole.

Step 3: Press the transfer device 10 proposed by the present invention on the temporary receiving substrate 60 of the MicroLED 20, and strictly correspond one-to-one. Since the temporary receiving substrate 60 acts as a temporary transition, the interfacial adhesion force between the MicroLED 20 and the temporary receiving substrate 60 (such as a thermal release adhesive substrate or a UV release layer adhesive layer) can be reduced until disappear under certain action, so as to realize the Release of MicroLED array 20. This method includes heating and melting the adhesive layer to reduce the viscosity or reducing the viscosity by irradiating the adhesive layer with ultraviolet light, etc., which will not be repeated here. Since the interface viscosity between the temporary receiving substrate 60 and the temporary receiving substrate 60 is reduced, the transfer device 10 can peel off the MicroLED as a whole. 20.

Step 4: Move the transfer device 10 with the prepared MicroLED array 20 to the laser driving platform.

Step 5: Turn on the laser during the transfer process to generate laser light 40 , and drive the dynamic release layer 12 in the transfer device 10 to vaporize, and generate bubbles to push the MicroLED 20 into contact with the receiving substrate 30 .

Step 6: Slowly apply the peeling force 50 and lift the transfer device so that the MicroLED 20 and the transfer device 10 are gradually delaminated

Step 7: The transfer is completed, and the transfer device 10 is lifted.

In this mass transfer method, before picking up the chip, the MicroLED adhered on the stamp is separated from the receiving substrate by a small distance, and the laser is used to generate a bubble height close to the distance between the MicroLED and the substrate, so that the chip and the receiving substrate are separated from the original. The non-contact is turned into a weak contact, and at the same time, the laser is used to generate gas in the bubble, and due to cooling, a rebound force is generated, and the chip is transferred on the circuit substrate.

Further preferably, a tiny distance between the MicroLEDs adhered on the stamp and the receiving substrate may be 10-500 μm.

Further preferably, when the laser acts on the seal, the height of the bubbles generated is generally 10-500 μm.

A是MicroLED芯片和电路基板的接触面积，C是动态释放层的刚度，G_crit是电路基板的粘附能量，v_crit是电路基板的临界剥离速率，v是鼓泡的回弹速度。Further preferably, the resilience needs to satisfy

A is the contact area between the MicroLED chip and the circuit substrate, C is the stiffness of the dynamic release layer, G _crit is the adhesion energy of the circuit substrate, v _crit is the critical peeling rate of the circuit substrate, and v is the rebound speed of the bubbling.

The dynamic release layer 12 can be polyimide (PI), metal films (eg, gold, aluminum), GaN films, triazene polymers, and the like.

The adhesive layer 13 may be a viscoelastic material such as polydimethylsiloxane (PDMS), epoxy resin or the like.

The thickness of the dynamic release layer 12 and the viscous layer 13 can be strictly controlled by spin coating parameters, so that the bubbling of the transfer device can be fully deformed under the action of the laser in the later stage.

The laser in the laser lift-off technology can be 308nm/248nm/266nm excimer laser, 355nm femtosecond laser, etc.

The laser can be: ①When the dynamic release layer is polyimide (PI), it can choose 308nm, 248nm, 355nm laser; ②When the dynamic release layer is a metal film, the laser can choose 1064nm, 808nm and other infrared lasers ; ③ When the dynamic release layer is GaN, the laser can be 533nm, 248nm, 266nm and other lasers at this time.

Those skilled in the art can easily understand that the above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention, etc., All should be included within the protection scope of the present invention.

Claims (10)

1. A laser projection approaching mass transfer device, characterized in that the device comprises a support layer (11), a dynamic release layer (12) and an adhesive layer (13), wherein, The support layer (11) is a base layer, the dynamic release layer (12) is arranged on the base layer, and the adhesive layer (13) is arranged on the dynamic release layer for contacting the MicroLED to be transferred , when the laser is irradiated on the dynamic release layer (12) through the support layer (11), the dynamic release layer (12) undergoes ablation or a phase change, thereby bulging and making the adhesive layer (13) Bubbling is also generated, thereby reducing the contact with the MicroLED to be transferred, and realizing the peeling of the transfer device from the MicroLED to be transferred. 2. The laser projection proximity mass transfer device according to claim 1, wherein the material used for the dynamic release layer (12) is polyimide, GaN, triazene polymer, gold and one of titanium. 3 . The laser projection proximity mass transfer device according to claim 2 , wherein the dynamic release layer has a thickness of 5 μm˜15 μm. 4 . 4. A laser projection proximity mass transfer device according to claim 1 or 2, wherein the adhesive layer (13) is a viscoelastic material, which is polydimethylsiloxane or epoxy resin . 5 . The laser projection proximity mass transfer device according to claim 4 , wherein the thickness of the adhesive layer is 30 μm˜40 μm. 6 . 6. The laser projection proximity mass transfer device according to claim 1 or 2, wherein the material of the support layer (11) is sapphire or quartz. 7 . The laser projection proximity mass transfer device according to claim 6 , wherein the thickness of the support layer is 500 μm˜1000 μm. 8 . 8. A method for carrying out mass transfer by the laser projection approaching mass transfer device according to any one of claims 1-7, wherein the method comprises the following steps: S1 sets the mass transfer device above the MicroLED to be transferred, and corresponds one by one; S2 uses a laser to irradiate the mass transfer device, and the laser passes through the support layer and irradiates the dynamic release layer, so that the dynamic release layer is ablated or phase-change bubbling occurs, and the adhesive layer of the mass transfer device and the MicroLED to be transferred are The interface contact area is reduced; The S3 mass transfer device bubbling to produce a rebound, allowing the MicroLED to be completely peeled from the stamp and successfully transferred to the receiving substrate. 9. A system for performing laser projection on the laser projection proximity mass transfer device according to any one of claims 1-7, characterized in that the system comprises a light source (41), an attenuator (42), a telephoto A unit (43), a light homogenizer (44), a spot projection unit (45) and a motion platform (90), wherein: The attenuator (42) is arranged in front of the light source (41) for adjusting the output energy of the laser light emitted by the light source (41); the telephoto unit (43) is arranged at the attenuator (42) ) rear, for expanding and shaping the light spot from the attenuator (42); the light homogenizer (44) is arranged behind the telephoto unit, for beam expansion and shaping from the attenuator (43) ) to intercept a section of light beam with stable wavelength; the spot projection unit (45) is arranged behind the light homogenizer (44) for patterning and focusing the light from the light homogenizer, so The motion platform (90) is arranged below the light spot projection unit (45), and is used for placing the laser projection proximity type mass transfer device according to any one of claims 1-4. 10. The system for laser projection according to claim 9, wherein the system further comprises a mirror, between the attenuator and the telephoto unit, the light homogenizer and the spot projection unit There are mirrors between them to change the direction of the light path.

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