CN114551324A - Transfer method of micro device - Google Patents
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- CN114551324A CN114551324A CN202210439216.2A CN202210439216A CN114551324A CN 114551324 A CN114551324 A CN 114551324A CN 202210439216 A CN202210439216 A CN 202210439216A CN 114551324 A CN114551324 A CN 114551324A
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
- H01L21/683—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping
- H01L21/6835—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping using temporarily an auxiliary support
- H01L21/6836—Wafer tapes, e.g. grinding or dicing support tapes
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
- H01L21/67005—Apparatus not specifically provided for elsewhere
- H01L21/67011—Apparatus for manufacture or treatment
- H01L21/67144—Apparatus for mounting on conductive members, e.g. leadframes or conductors on insulating substrates
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L25/00—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof
- H01L25/03—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes
- H01L25/04—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers
- H01L25/075—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers the devices being of a type provided for in group H01L33/00
- H01L25/0753—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers the devices being of a type provided for in group H01L33/00 the devices being arranged next to each other
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2221/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof covered by H01L21/00
- H01L2221/67—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere
- H01L2221/683—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere for supporting or gripping
- H01L2221/68304—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere for supporting or gripping using temporarily an auxiliary support
- H01L2221/68363—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere for supporting or gripping using temporarily an auxiliary support used in a transfer process involving transfer directly from an origin substrate to a target substrate without use of an intermediate handle substrate
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2221/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof covered by H01L21/00
- H01L2221/67—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere
- H01L2221/683—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere for supporting or gripping
- H01L2221/68304—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere for supporting or gripping using temporarily an auxiliary support
- H01L2221/68381—Details of chemical or physical process used for separating the auxiliary support from a device or wafer
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Abstract
The application relates to a micro device transfer method, which comprises the following steps: providing a transparent substrate, wherein one side of the transparent substrate is provided with an expandable sacrificial layer, the expandable sacrificial layer is provided with a first adhesive layer, and a plurality of micro devices are adhered to the transparent substrate through the first adhesive layer; aligning one side of the transparent substrate, which is adhered with the micro device, with a carrier substrate; irradiating a target area from the side of the transparent substrate to which the micro devices are not attached by using a laser, acting on the expandable sacrificial layer at the target area to expand, and curing the first adhesive layer at the target area to reduce the viscosity, so that the target micro devices in the target area are transferred onto the carrier substrate. Through the accurate, local inflation effect and the local solidification effect to first viscose layer of carrying out fast to the expandable sacrificial layer in target area of laser, resistance when effectively reducing the miniature device of target and the separation of first viscose layer improves and shifts precision and success rate, and shifts the high-efficient easy operation of process.
Description
Technical Field
The application relates to the technical field of micro devices, in particular to a transfer method of a micro device.
Background
An LED is a semiconductor electronic element capable of emitting light, and has advantages of high energy conversion efficiency, short reaction time, long service life, etc., and a Micro LED (Micro-LED) is a Micro device obtained by making a conventional LED structure into a thin film, a Micro-structure, and an array. The manufacturing of a large-size and high-resolution Micro-LED display screen requires the Transfer assembly of millions or tens of millions of micron-sized Micro-LED chips, and Mass Transfer (MTP) requires the precise Transfer and fixation of the micron-sized Micro-LED chips from a donor wafer onto a target substrate, so that a mobile phone screen using the Micro-LED is mounted at the current mainstream LED die-fixing speed in tens of days. Therefore, a new micro device transfer method needs to be proposed.
Disclosure of Invention
In view of the above technical problems, the present application provides a method for transferring a micro device, which can improve the transferring precision and success rate, and the transferring process is efficient and easy to operate.
In order to solve the above technical problem, the present application provides a method for transferring a micro device, including the following steps:
s1, providing a transparent substrate, wherein one side of the transparent substrate is provided with an expandable sacrificial layer, the expandable sacrificial layer is provided with a first adhesive layer, and a plurality of micro devices are adhered to the transparent substrate through the first adhesive layer;
s2, aligning the side of the transparent substrate adhered with the micro device with a carrier substrate;
irradiating a target area from the side of the transparent substrate to which the micro device is not attached by using a laser, acting the expandable sacrificial layer at the target area to expand, and curing the first adhesive layer at the target area to reduce viscosity, so that the target micro device in the target area is transferred onto the carrier substrate S3.
Optionally, the viscosity of the first adhesive layer in the target area after absorbing the laser energy is 1/10-1/1000 of the initial viscosity.
Optionally, the expandable sacrificial layer is a layer of material comprising at least one of a triazene polymer, a polyimide modified polymer, mica.
Optionally, the step S2 includes:
providing the carrier substrate, wherein one side of the carrier substrate is provided with a second adhesive layer;
and aligning and attaching the side of the transparent substrate, to which the micro device is adhered, to the side of the carrier substrate, to which the second adhesive layer is provided, or aligning the side of the transparent substrate, to which the micro device is adhered, to the side of the carrier substrate, to which the second adhesive layer is provided, according to a preset distance.
Optionally, the second adhesive layer is made of an elastic material, and the viscosity of the second adhesive layer is smaller than the viscosity of the first adhesive layer before the first adhesive layer absorbs the laser energy and is greater than the viscosity of the first adhesive layer after the first adhesive layer absorbs the laser energy.
Optionally, before the step S3, the method further includes:
determining a first target laser energy corresponding to the thickness of the expandable sacrificial layer in the target area, and determining a second target laser energy corresponding to the target viscosity difference of the first adhesive layer in the target area before and after the first adhesive layer absorbs the laser energy;
determining target laser energy for irradiating the target area according to the first target laser energy and the second target laser energy;
and determining at least one of the distance between the focusing spot of the laser and the transparent substrate, the laser frequency and the laser power according to the target laser energy.
Optionally, the target laser energy is greater than or equal to a sum of the first target laser energy and the second target laser energy.
Optionally, after the step of S3, the method further includes:
s4: aligning and attaching one side of the carrier substrate, on which the target micro device is adhered, to a receiving side of a receiving substrate;
s5: reducing the viscosity of the second adhesive layer to transfer the target micro device onto the receiving substrate.
Optionally, the Micro device is a Micro-LED, and before the step S5, the method further includes:
and heating the receiving substrate to bond the target micro device with the welding point on the receiving side of the receiving substrate.
Optionally, alignment marks are respectively disposed on the transparent substrate, the carrier substrate, and the receiving substrate.
The transfer method of the micro device comprises the following steps: providing a transparent substrate, wherein one side of the transparent substrate is provided with an expandable sacrificial layer, the expandable sacrificial layer is provided with a first adhesive layer, and a plurality of micro devices are adhered to the transparent substrate through the first adhesive layer; aligning one side of the transparent substrate, which is adhered with the micro device, with a carrier substrate; irradiating a target area from the side of the transparent substrate to which the micro devices are not attached by using a laser, acting on the expandable sacrificial layer at the target area to expand, and curing the first adhesive layer at the target area to reduce the viscosity, so that the target micro devices in the target area are transferred onto the carrier substrate. Through the accurate, local inflation effect and the local solidification effect to first viscose layer of carrying out fast to the expandable sacrificial layer in target area of laser, resistance when effectively reducing the miniature device of target and the separation of first viscose layer improves and shifts precision and success rate, and shifts the high-efficient easy operation of process.
Drawings
Fig. 1 is a schematic flow chart illustrating a method of transferring a micro device according to a first embodiment.
Fig. 2 is a schematic diagram showing a step S1 in the transfer method of the micro device shown in the first embodiment.
Fig. 3 is an enlarged schematic view of region I in fig. 2.
Fig. 4 is a schematic diagram showing steps S2 and S3 in the transfer method of the micro device according to the first embodiment.
Fig. 5 is an enlarged schematic view of region II in fig. 4.
Fig. 6 is a comparison of before and after laser irradiation, in which (a) is a plan view before laser irradiation and (b) is a plan view after laser irradiation.
Fig. 7 is a schematic view of a structure obtained at step S3 in the transfer method of a micro device shown in the first embodiment.
Detailed Description
The following description of the embodiments of the present application is provided for illustrative purposes, and other advantages and capabilities of the present application will become apparent to those skilled in the art from the present disclosure.
In the following description, reference is made to the accompanying drawings that describe several embodiments of the application. It is to be understood that other embodiments may be utilized and that mechanical, structural, electrical, and operational changes may be made without departing from the spirit and scope of the present application. The following detailed description is not to be taken in a limiting sense, and the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
Although the terms first, second, etc. may be used herein to describe various elements in some instances, these elements should not be limited by these terms. These terms are only used to distinguish one element from another.
Also, as used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context indicates otherwise. It will be further understood that the terms "comprises," "comprising," "includes" and/or "including," when used in this specification, specify the presence of stated features, steps, operations, elements, components, items, species, and/or groups, but do not preclude the presence, or addition of one or more other features, steps, operations, elements, components, species, and/or groups thereof. The terms "or" and/or "as used herein are to be construed as inclusive or meaning any one or any combination. Thus, "A, B or C" or "A, B and/or C" means "any of the following: a; b; c; a and B; a and C; b and C; A. b and C ". An exception to this definition will occur only when a combination of elements, functions, steps or operations are inherently mutually exclusive in some way.
First embodiment
Fig. 1 is a schematic flow chart illustrating a method of transferring a micro device according to a first embodiment. As shown in fig. 1, the transfer method of the micro device of the present application includes the following steps:
s1, providing a transparent substrate, wherein one side of the transparent substrate is provided with an expandable sacrificial layer, the expandable sacrificial layer is provided with a first adhesive layer, and the plurality of micro devices are adhered to the transparent substrate through the first adhesive layer;
s2, aligning the side of the transparent substrate adhered with the micro device with a carrier substrate;
and S3, irradiating the target area from the side of the transparent substrate where the micro devices are not adhered by using a laser, acting the expandable sacrificial layer on the target area to expand, and curing the first adhesive layer on the target area to reduce viscosity, so that the target micro devices in the target area are transferred to the carrier substrate.
Referring to fig. 2, in step S1, the transparent substrate 10 may be a sapphire substrate or other transparent material, one side of the transparent substrate 10 has an expandable sacrificial layer 11, and the expandable sacrificial layer 11 can be expanded volumetrically under laser irradiation, preferably, the expandable sacrificial layer 11 is a cleavable material layer, so that it can be cleaved under laser irradiation to expand directionally, and through energy transfer inside the expandable sacrificial layer 11, a pushing force is generated to the transparent substrate 10. Alternatively, the expandable sacrificial layer 11 is a material layer containing at least one of a triazene polymer, a polyimide modified polymer, and mica, so that it can be cleaved and expanded in volume by laser irradiation.
The side of the expandable sacrificial layer 11 facing away from the transparent substrate 10 is provided with a first adhesive layer 12, and the first adhesive layer 12 can be formed by a coating method such as spin coating or electrostatic spinning. The first adhesive layer 12 may be made of a photosensitive material, such as a photosensitive adhesive material for ultraviolet and infrared, and the first adhesive layer 12 used in this embodiment is made of an ultraviolet-sensitive adhesive material, and optionally, the ultraviolet-sensitive adhesive material includes the following components by weight percent: 20-50% of (methyl) acrylic acid alkyl ester, 15-40% of (methyl) acrylic acid hydroxyalkyl ester, 10-15% of N atom polar monomer, 10-20% of reactive diluent, 0.1-2% of chain transfer agent, 0.5-1% of thermal initiator and 0.5-1% of photoinitiator.
A plurality of micro devices are peeled off from the sapphire substrate by means of transfer and transferred onto the first adhesive layer 12, and the micro devices include non-target micro devices 31 that do not need to be transferred to a carrier substrate and target micro devices 32 that need to be transferred to the carrier substrate. Optionally, the Micro device comprises a Micro-LED. As shown in fig. 3, taking an example of an area where the target micro device 32 is located, when the target micro device 32 is transferred onto the first adhesive layer 12, the first adhesive layer 12 is not in a cured state, and under the action of surface tension of the first adhesive layer 12, corners of the target micro device 32 will sink into the first adhesive layer 12 to form a state that the bottom is wrapped by the first adhesive layer 12, at this time, if the first adhesive layer 12 is cured, the cured first adhesive layer 12 will wrap the bottom of the target micro device 32 to generate resistance to peeling of the target micro device 32.
Referring to fig. 4, in step S2, a carrier substrate 40 is provided, one side of the carrier substrate 40 has a second adhesive layer 41, and the side of the transparent substrate 10 adhered with the micro devices is aligned with the side of the carrier substrate 40 having the second adhesive layer 41 at a predetermined distance, that is, the second adhesive layer 41 is spaced from the micro devices by a distance, for example, 30 to 70nm, which is set according to the thickness difference between the expandable sacrificial layer 11 before and after expansion, so that after the laser 50 irradiates, the target micro devices 32 can be pushed to contact the second adhesive layer 41 and adhered to the second adhesive layer 41, so as to obtain a suitable adhesion force, and reduce the wrapping degree of the first adhesive layer 12 on the bottom corners of the target micro devices 32, thereby facilitating detachment. Alternatively, the side of the transparent substrate 10 to which the micro devices are adhered may be aligned with the side of the carrier substrate 40 having the second adhesive layer 41, that is, the second adhesive layer 41 is in direct contact with the micro devices, so that the target micro devices 32 may be pushed to be adhered to the second adhesive layer 41 more closely after the laser 50 is irradiated, thereby facilitating detachment. Optionally, the transparent substrate 10 and the carrier substrate 40 are provided with alignment marks to enable more accurate alignment between the transparent substrate 10 and the carrier substrate 40.
The viscosity of the second adhesive layer 41 is lower than the viscosity of the first adhesive layer 12 before the laser energy is absorbed and higher than the viscosity of the first adhesive layer 12 after the laser energy is absorbed, so that after the first adhesive layer 12 is irradiated by the laser 50 and the viscosity is reduced, the adhesive force between the target micro device 32 on the first adhesive layer 12 at the position irradiated by the laser 50 and the first adhesive layer 12 is lower than the adhesive force between the target micro device 32 and the second adhesive layer 41, and the target micro device 32 is transferred from the transparent substrate 10 to the carrier substrate 40. Optionally, the second adhesive layer 41 is made of an elastic material, which can fix the micro device, and can also serve as a buffer layer to absorb part of the stress when the micro device contacts the second adhesive layer 41, so as to reduce the breakage of the micro device.
Referring to fig. 4 and 5, in step S3, the expandable sacrificial layer 11 in the target area is irradiated by the laser 50 from the side of the transparent substrate 10 where the micro devices are not adhered, so that the expandable sacrificial layer 11 in the target area expands and protrudes toward the target micro device 32 to lift the target micro device 32, and in the process, the bottom corners of the target micro device 32 are separated from the first adhesive layer 12, so that the first adhesive layer 12 no longer covers the bottom corners of the target micro device 32 or the degree of covering the bottom corners of the target micro device 32 is reduced. As can be seen from fig. 6 (a), when the target micro device 32 is transferred onto the first adhesive layer 12, the first adhesive layer 12 is not in a cured state, under the surface tension of the first adhesive layer 12, the corners of the target micro device 32 will be sunk into the first adhesive layer 12, forming a state where the bottom is wrapped by the first adhesive layer 12, so that the first adhesive layer 12 around the corners of the target micro device 32 is depressed and in an arc-shaped state, as can be seen from (b) of fig. 6, after the laser 50 is irradiated, the depressions of the first adhesive layer 12 around the corners of the target micro device 32 disappear and are no longer in an arc state, this is because the expandable sacrificial layer 11 expands the protrusion toward the target micro device 32, after lifting the target micro device 32, the first adhesive layer 12 no longer encases the bottom corners of the target micro device 32 or reduces the degree of encasing the bottom corners of the target micro device 32. In addition, the surface tension effect of the first adhesive layer 12 on the target micro device 32 is reduced after the target micro device 32 is pushed forward by the expandable sacrificial layer 11.
On the basis, the laser 50 also cures the first adhesive layer 12 in the target area where the target micro device 32 is located, so as to reduce the viscosity of the first adhesive layer 12 in the target area. Thus, under the local expansion of the expandable sacrificial layer 11 and the local curing action of the first adhesive layer 12, the resistance when the target micro device 32 is separated from the first adhesive layer 12 is effectively reduced, the target micro device 32 is transferred onto the carrier substrate 40, the transfer success rate is improved, and when the expandable sacrificial layer 11 is subjected to volume-oriented expansion in a cracking mode, the influence on the surrounding area is small, and the transfer accuracy is higher. By providing the carrier substrate 40 with the second adhesive layer 41 to pick up the target micro device 32 from the transparent substrate 10 in a manner of contacting the target micro device 32, the target micro device 32 can be prevented from shifting during the transfer process, and the positioning accuracy is higher. As shown in fig. 7, the distance between the transferred target micro devices 32 is increased relative to the original distance of the micro devices on the transparent substrate 10, thereby achieving the purpose of extending the wafer array distance.
To more accurately realize the transfer, before the step of S3, the method further includes:
determining first target laser energy corresponding to the thickness of the expandable sacrificial layer located in the target area, and determining second target laser energy corresponding to the target viscosity difference of the first adhesive layer located in the target area before and after the first adhesive layer absorbs the laser energy;
determining target laser energy for irradiating the target area according to the first target laser energy and the second target laser energy;
and determining at least one of the distance between the focusing spot of the laser and the transparent substrate, the laser frequency and the laser power according to the target laser energy.
Wherein the first target laser energy corresponds to the thickness of the expandable sacrificial layer 11 at the target area. In particular, the interaction of the laser photons with the expandable sacrificial layer 11 starts from the interface of the transparent substrate 10 and the expandable sacrificial layer 11, the incident laser pulse causing a sudden local light splitting within the expandable sacrificial layer 11Considering that the intensity of the absorbed light decays with increasing propagation length, whether the volumetric expansion triggered by the laser 50 is sufficient to perforate and ablate the entire expandable sacrificial layer 11, or whether it is sufficient to strip and forward-eject the remaining top layer, depending on the thickness of the expandable sacrificial layer 11 and the energy density of the laser 50, the effect of the pressure thrust released upon expansion is required to be sufficient to overcome the mechanical resistance and cohesion of the remaining covering material. Taking the photolysis process of triazene chromophore as an example, the energy density is 30mJ/cm according to laser2~180mJ/cm2The values of ablation depth d (f) in between, a characteristic ablation curve can be obtained that fits well to the phenomenological equation:
wherein the content of the first and second substances,α eff is the effective absorption coefficient of the water-soluble polymer,α eff ≈56000cm-1；Fis the amount of the injected liquid,F th is the threshold fluence, i.e., the energy density of the laser 50,F th ≈28mJ/cm2. Thus, after the thickness of the expandable sacrificial layer 11 is determined, the ablation depth is determinedd（F) The value and thus the required laser energy can be determinedF。
The second target laser energy corresponds to a target viscosity difference of the first adhesive layer 12 in the target area before and after absorption of the laser energy. The focusing spot of the laser 50 in the minimum spot size of the specific lens is obtained by balancing diffraction and spot effect, so that the laser 50 is used as a polymerization initiator of the light-sensitive material of the first adhesive layer 12 to locally cure the first adhesive layer 12 in the target area where the target micro device 32 with a specific spacing is located, and the viscosity of the first adhesive layer 12 in the target area is reduced. Optionally, the laser 50 may be an active laser such as ultraviolet, infrared, etc., and the viscosity of the first adhesive layer 12 in the target area after absorbing the laser energy is preferably 1/10-1/1000 of the initial viscosity.
Specifically, the second target laser energy may be determined based on a preset model, where the preset model is a model obtained based on experimental data optimization, and is used to characterize a relationship between the laser energy of the laser 50, a viscosity difference of the first adhesive layer 12 before and after absorbing the laser energy, and a transfer result of the target micro device 32 from the transparent substrate 10 to the carrier substrate 40. The target viscosity difference of the first adhesive layer 12 before and after absorbing the laser energy may be determined according to reference factors such as the type of the material of the first adhesive layer 12, the thickness of the first adhesive layer 12, the size of the target micro device 32, and the like, and then the target viscosity difference is input into a preset model, and based on the laser energy and the transfer result output by the preset model, the laser energy that may be selected when the transfer result is successful is determined, that is, the second target laser energy.
Optionally, to obtain the preset model, the method of the present application further includes:
carrying out a plurality of groups of experiments;
collecting a plurality of groups of experimental data, wherein the experimental data comprise laser energy, viscosity difference of the first adhesive layer and a transfer result of the micro device from the transparent substrate to the carrier substrate;
and training the SVM model by taking the multiple groups of experimental data as training data, and optimizing parameters of the SVM model by adopting a PSO algorithm to obtain a preset model.
Alternatively, in order to distinguish whether the result of transferring the micro devices from the transparent substrate 10 to the carrier substrate 40 is successful, a classifier model based on SVM (Support Vector Machine) is required. In the present embodiment, a gaussian kernel function is introduced as a kernel function of the SVM-based classifier model to recognize the characteristic signal, the transfer experiment of the micro device from the transparent substrate 10 to the carrier substrate 40 is repeatedly performed several hundred times, the laser energy and the viscosity difference of the first adhesive layer 12 before and after the absorption of the laser energy are extracted from the experimental data as the characteristic signal, and the training data includes a large amount of laser energy, the viscosity difference of the first adhesive layer 12, and the transfer result of the micro device from the transparent substrate 10 to the carrier substrate 40. In order to improve classification, a PSO (Particle Swarm Optimization) algorithm is adopted to optimize parameters of the SVM model. The PSO algorithm can realize global optimization by iteratively searching for an optimal solution and utilizing a local optimal value. Finally, classification accuracy can be achieved based on the SVM model, and the transfer process is optimized by adjusting the transfer parameters of the model. The transfer process of the micro device can be optimized based on the prediction result of the SVM model, and automatic large-scale transfer of the micro device is facilitated.
Optionally, the laser used in this embodiment is a solid laser, and is composed of a laser working substance, a pump source, a light-gathering cavity and an optical resonant cavity, wherein the working substance is a crystal or glass seed as a matrix material, and a small amount of active ions are uniformly doped in the crystal or glass seed. Tunable Ce is selected in the embodiment3+The laser, which accomplishes focusing the laser beam by means of a mirror, focuses a large beam to a single precise spot, and the spot is extremely dense thermally. Optionally, the laser focusing device may be one or more.
Optionally, considering the thrust of the target micro device 32 when the expandable sacrificial layer 11 is ejected forward, the energy requirement of the first adhesive layer 12 is combined, and the target laser energy is greater than or equal to the sum of the first target laser energy and the second target laser energy, for example, 79 to 125mJ/cm2. Further, at least one of the distance between the focal spot of the laser light 50 and the transparent substrate 10, the laser frequency, and the laser power is determined according to the target laser energy. The laser 50 is used as the expansion excitation energy of the expandable sacrificial layer 11 and the polymerization initiator of the first adhesive layer 12, and the distance between the focal spot of the laser 50 and the transparent substrate 10 is adjusted to adjust the expansion range of the expandable sacrificial layer 11 and the polymerization degree and fluctuation range of the first adhesive layer 12, especially the fluctuation range of the polymerization initiator should not affect the adjacent micro devices, especially the non-target micro devices 31 which do not need to be transferred, so that after the required target laser energy is determined, the optimal distance is adjusted and the corresponding laser frequency and laser power are determined, so that the target micro devices 32 can be guaranteed to be transferred, the adjacent non-target micro devices 31 are not transferred, and the transfer accuracy is improved.
Optionally, after the step of S3, the method further includes:
s4: aligning and attaching one side of the carrier substrate, on which the target micro device is adhered, to a receiving side of the receiving substrate;
s5: the viscosity of the second adhesive layer is reduced to transfer the target micro device to the receiving substrate.
Optionally, alignment marks are respectively disposed on the carrier substrate 40 and the receiving substrate, and the carrier substrate 40 and the receiving substrate are aligned through the alignment marks. Alternatively, the second adhesive layer 41 may be a viscosity-variable material, including but not limited to a heat-sensitive material, a photosensitive material, a single-component polymer, or a multi-component polymer, so that the viscosity of the second adhesive layer 41 can be reduced by subjecting the carrier substrate 40 to heating and/or light irradiation, and the target micro device 32 can be transferred to the receiving substrate when the bonding force between the target micro device 32 and the receiving substrate is greater than the bonding force between the target micro device 32 and the carrier substrate 40.
Optionally, the Micro device is a Micro-LED, and before the step S5, the method further includes:
the receiving substrate is heated to bond the target micro device to the pads on the receiving side of the receiving substrate.
After the target micro device 32 is bonded to the solder pads on the receiving side of the receiving substrate, the bonding force between the target micro device 32 and the receiving substrate will be greater than the adhesion force with the carrier substrate 40, and the target micro device 32 can be transferred to the receiving substrate by separating the carrier substrate 40 from the receiving substrate.
In this way, this application has improved the difficult problem of counterpoint and the success rate that miniature device shifts existence among the laser lift-off technology, under the local solidification effect on the local inflation of expandable sacrificial layer and first viscose layer, resistance when effectively reducing miniature device of target and first viscose layer separation, it still can't break away from first viscose layer smoothly to avoid laser to handle the miniature device of back to first viscose layer, the success rate of shifting has been improved, and utilize the viscose layer to bear the miniature device of target of local solidification, can improve the counterpoint effect, the defective rate of miniature device has been reduced. In addition, the laser local solidification is adopted, a mask pattern does not need to be prepared, the process is simple and easy to operate, the cost is reduced, and the method is an effective method for efficient selective batch transfer of the micro devices.
The transfer method of the micro device comprises the following steps: providing a transparent substrate, wherein one side of the transparent substrate is provided with an expandable sacrificial layer, the expandable sacrificial layer is provided with a first adhesive layer, and a plurality of micro devices are adhered to the transparent substrate through the first adhesive layer; aligning one side of the transparent substrate, which is adhered with the micro device, with a carrier substrate; irradiating a target area from the side of the transparent substrate to which the micro devices are not attached by using a laser, acting on the expandable sacrificial layer at the target area to expand, and curing the first adhesive layer at the target area to reduce the viscosity, so that the target micro devices in the target area are transferred onto the carrier substrate. Through the accurate, local inflation effect and the local solidification effect to first viscose layer of carrying out fast to the expandable sacrificial layer in target area of laser, resistance when effectively reducing the miniature device of target and the separation of first viscose layer improves and shifts precision and success rate, and shifts the high-efficient easy operation of process.
The above embodiments are merely illustrative of the principles and utilities of the present application and are not intended to limit the application. Any person skilled in the art can modify or change the above-described embodiments without departing from the spirit and scope of the present application. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical concepts disclosed in the present application shall be covered by the claims of the present application.
Claims (10)
1. A method for transferring a micro device, comprising the steps of:
s1, providing a transparent substrate, wherein one side of the transparent substrate is provided with an expandable sacrificial layer, the expandable sacrificial layer is provided with a first adhesive layer, and a plurality of micro devices are adhered to the transparent substrate through the first adhesive layer;
s2, aligning the side of the transparent substrate adhered with the micro device with a carrier substrate;
irradiating a target area from the side of the transparent substrate to which the micro device is not attached by using a laser, acting the expandable sacrificial layer at the target area to expand, and curing the first adhesive layer at the target area to reduce viscosity, so that the target micro device in the target area is transferred onto the carrier substrate S3.
2. The method of claim 1, wherein the viscosity of the first adhesive layer in the target area after absorbing the laser energy is 1/10-1/1000 of the initial viscosity.
3. The method of transferring a micro device according to claim 1, wherein the expandable sacrificial layer is a layer of material comprising at least one of a triazene polymer, a polyimide modified polymer, mica.
4. The method for transferring a micro device according to claim 1, wherein the step S2 includes:
providing the carrier substrate, wherein one side of the carrier substrate is provided with a second adhesive layer;
and aligning and attaching the side of the transparent substrate, to which the micro device is adhered, to the side of the carrier substrate, to which the second adhesive layer is provided, or aligning the side of the transparent substrate, to which the micro device is adhered, to the side of the carrier substrate, to which the second adhesive layer is provided, according to a preset distance.
5. The method of claim 4, wherein the second adhesive layer is an elastic material, and the viscosity of the second adhesive layer is less than the viscosity of the first adhesive layer before the first adhesive layer absorbs the laser energy and greater than the viscosity of the first adhesive layer after the first adhesive layer absorbs the laser energy.
6. The method for transferring a micro device according to any one of claims 1 to 5, wherein the step of S3 is preceded by the steps of:
determining a first target laser energy corresponding to the thickness of the expandable sacrificial layer in the target area, and determining a second target laser energy corresponding to the target viscosity difference of the first adhesive layer in the target area before and after the first adhesive layer absorbs the laser energy;
determining target laser energy for irradiating the target area according to the first target laser energy and the second target laser energy;
and determining at least one of the distance between the focusing spot of the laser and the transparent substrate, the laser frequency and the laser power according to the target laser energy.
7. The method of transferring a micro device according to claim 6, wherein the target laser energy is greater than or equal to the sum of the first target laser energy and the second target laser energy.
8. The method for transferring a micro device according to claim 4 or 5, further comprising, after the step of S3:
s4: aligning and attaching one side of the carrier substrate, on which the target micro device is adhered, to a receiving side of a receiving substrate;
s5: and reducing the viscosity of the second adhesive layer to transfer the target micro device to the receiving substrate.
9. The method for transferring a Micro device according to claim 8, wherein the Micro device is a Micro-LED, and before the step S5, the method further comprises:
and heating the receiving substrate to bond the target micro device with the welding point on the receiving side of the receiving substrate.
10. The method of claim 8, wherein the transparent substrate, the carrier substrate and the receiving substrate are respectively provided with alignment marks.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115124261A (en) * | 2022-07-25 | 2022-09-30 | 浙江清华柔性电子技术研究院 | Glass repairing method |
| CN117276172A (en) * | 2023-11-22 | 2023-12-22 | 清华大学 | Micro device transfer device and transfer method |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103597589A (en) * | 2011-04-11 | 2014-02-19 | 北达科他州立大学研究基金会 | Selective laser-assisted transfer of discrete components |
| CN109417065A (en) * | 2017-06-12 | 2019-03-01 | 尤尼卡尔塔股份有限公司 | Parallel composition of the discrete assembly on substrate |
| CN109661122A (en) * | 2018-11-09 | 2019-04-19 | 华中科技大学 | It is a kind of suitable for micro-led selective flood tide transfer method |
| CN110797295A (en) * | 2019-11-15 | 2020-02-14 | 广东省半导体产业技术研究院 | Chip transfer method and device |
| CN113021874A (en) * | 2021-03-01 | 2021-06-25 | 广东工业大学 | Single cell printing method based on annular laser spot induced transfer |
| CN113764548A (en) * | 2021-09-02 | 2021-12-07 | 浙江清华柔性电子技术研究院 | Transfer method of micro device |
| CN113921442A (en) * | 2020-07-09 | 2022-01-11 | 重庆康佳光电技术研究院有限公司 | Chip transfer assembly and manufacturing method thereof, chip transfer method and display back plate |
| CN114050216A (en) * | 2021-10-28 | 2022-02-15 | 华中科技大学 | Flexible electronic device and laser processing method thereof |
-
2022
- 2022-04-25 CN CN202210439216.2A patent/CN114551324A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103597589A (en) * | 2011-04-11 | 2014-02-19 | 北达科他州立大学研究基金会 | Selective laser-assisted transfer of discrete components |
| CN109417065A (en) * | 2017-06-12 | 2019-03-01 | 尤尼卡尔塔股份有限公司 | Parallel composition of the discrete assembly on substrate |
| CN109661122A (en) * | 2018-11-09 | 2019-04-19 | 华中科技大学 | It is a kind of suitable for micro-led selective flood tide transfer method |
| CN110797295A (en) * | 2019-11-15 | 2020-02-14 | 广东省半导体产业技术研究院 | Chip transfer method and device |
| CN113921442A (en) * | 2020-07-09 | 2022-01-11 | 重庆康佳光电技术研究院有限公司 | Chip transfer assembly and manufacturing method thereof, chip transfer method and display back plate |
| CN113021874A (en) * | 2021-03-01 | 2021-06-25 | 广东工业大学 | Single cell printing method based on annular laser spot induced transfer |
| CN113764548A (en) * | 2021-09-02 | 2021-12-07 | 浙江清华柔性电子技术研究院 | Transfer method of micro device |
| CN114050216A (en) * | 2021-10-28 | 2022-02-15 | 华中科技大学 | Flexible electronic device and laser processing method thereof |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115124261A (en) * | 2022-07-25 | 2022-09-30 | 浙江清华柔性电子技术研究院 | Glass repairing method |
| CN117276172A (en) * | 2023-11-22 | 2023-12-22 | 清华大学 | Micro device transfer device and transfer method |
| CN117276172B (en) * | 2023-11-22 | 2024-02-06 | 清华大学 | Micro device transfer device and transfer method |
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