Thin film gallium arsenide cell stripping and transferring system and method based on thermal / light regulation and control

Abstract

The invention relates to the technical field of advanced semiconductor manufacturing equipment, in particular to a thin film gallium arsenide cell stripping and transferring system and method based on thermal / light regulation and control. The target substrate bearing table bears and fixes a target substrate, and a heater is arranged in the target substrate bearing table; the visual positioning module is used for identifying and positioning the thin film battery unit and the bonding area and outputting coordinate information; the laser lift-off module carries out scanning irradiation on the sacrificial layer according to the coordinate information; the flexible carrier film processing module attaches a flexible carrier film to the surface of the thin film battery unit; and the central control module generates a laser scanning path control instruction, controls the multi-degree-of-freedom transfer robot, and peels the thin film battery unit from the growth substrate and transfers the thin film battery unit to a target substrate for combination. According to the method, the processing steps are simplified, the dependence on chemicals is reduced, the accuracy and the production efficiency are improved through automatic operation, and the possibility and the reliability of the thin-film solar cell in flexible application are expanded.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of advanced semiconductor manufacturing equipment, in particular to a thin film gallium arsenide battery stripping and transferring system and method based on thermal / optical regulation. BACKGROUND

[0002] The thin film gallium arsenide battery stripping and transferring is an automated technology for efficiently and safely separating the thin film gallium arsenide solar cell from the growth substrate of GaAs, Ge or Si, and transferring it to the flexible target substrate of polyimide or titanium foil. The thin film gallium arsenide battery has great application potential in space solar energy and wearable devices due to its high efficiency, high power-to-weight ratio and excellent radiation resistance. However, in order to realize the flexibility and portability of the battery, the several-micron-thick epitaxial functional layer of the battery must be stripped from the original substrate and precisely transferred to the lightweight flexible substrate.

[0003] In the prior art, the thin film gallium arsenide battery stripping technology is mostly achieved by introducing a sacrificial layer of AlAs on the substrate and dissolving the sacrificial layer by chemical wet etching to separate the thin film. However, in actual application process, waste liquid is generated during production by using strong corrosive chemicals, which increases the environmental burden, and it is also difficult to avoid the large-area non-uniformity in chemical etching, which also causes low stripping efficiency, slow etching speed and other problems. At the same time, the thin film is prone to breakage, curling or contamination during stripping, transferring and drying, and the process relies heavily on manual operation, making it difficult to achieve high yield automation. As a dry process, laser stripping technology avoids chemical pollution, but it requires very high control of laser energy, and slight deviation in the stripping process will cause damage to the functional layer or incomplete stripping. At the same time, the stripped thin film is difficult to be reliably picked up and precisely transferred in a suspended state, and the thermal stress generated by high-speed laser scanning often causes micro-cracks in the thin film, reducing the overall performance of the thin film.

[0004] Therefore, in view of the above technical problems, there is an urgent need for an improved technical solution to weaken the stripping layer by using the combined action of light and heat, and to complete the non-destructive pickup and reliable transfer of the thin film by combining with the mechanical platform, to ensure the efficiency of the stripping process, thereby improving the yield and environmental friendliness. SUMMARY

[0005] In view of at least one of the above technical problems, the present application provides a thin film gallium arsenide battery stripping and transferring system and method based on thermal / optical regulation, which uses the combined action of light and heat to realize the efficiency of the stripping process and improve the yield and environmental friendliness.

[0006] According to a first aspect of the present application, a thin film gallium arsenide battery stripping and transferring system based on thermal / optical regulation is provided, comprising:

[0007] A growth substrate carrier for carrying and fixing a growth substrate on which thin film battery cells are grown, the growth substrate and the thin film battery cells having a sacrificial layer therebetween;

[0008] A target substrate carrier for carrying and fixing a target substrate having a bonding area thereon, the target substrate carrier having a built-in heater for heat treating the target substrate during the transfer and bonding of the thin film battery cells;

[0009] A visual positioning module for identifying and locating the thin film battery cells on the growth substrate and the bonding area on the target substrate and outputting coordinate information;

[0010] A laser lift-off module for selectively scanning and irradiating the sacrificial layer around the thin film battery cells according to the coordinate information;

[0011] A flexible carrier film processing module including an unwinding mechanism, a winding mechanism, a tension controller, and a mounting head including a force sensor and a roller pressing assembly, for attaching a flexible carrier film to the surface of the thin film battery cells;

[0012] A central control module connected to the visual positioning module, the laser lift-off module, and the flexible carrier film processing module, for coordinating and controlling the operation of the modules of the system and generating laser scanning path control instructions;

[0013] A multi-degree-of-freedom transfer robot including an end effector integrated with the mounting head, the central control module controlling the multi-degree-of-freedom transfer robot to lift off the thin film battery cells from the growth substrate and transfer them to the target substrate for bonding.

[0014] In some embodiments of the present application, the laser lift-off module includes a laser, a scanning galvanometer for pattern scanning of the laser beam emitted by the laser in the X-Y plane, and a coaxial cooling element for locally cooling the growth substrate during laser scanning.

[0015] In some embodiments of the present application, the wavelength of the laser is 248 nm, 355 nm, or 532 nm, the laser energy density is lower than the damage threshold of the gallium arsenide epitaxial layer of the thin film battery cells and higher than the decomposition threshold of the sacrificial layer material, and the scanning path is a closed loop path along the inside 1-10 μm of the battery cell boundary.

[0016] In some embodiments of the present application, the flexible polymer carrier film in the flexible carrier film processing module is an ultraviolet curing adhesive film or a heat curing release adhesive film, and the adhesion of the flexible polymer carrier film to the battery layer in the uncured state is the residual adhesion of the sacrificial layer to the battery layer after laser irradiation between the following: wherein is a safety factor of 1.2-3.0; the adhesion of the flexible high polymer carrier film to the battery layer after curing is the final bonding force between the battery layer and the target substrate bonding area between the following: wherein is a peeling factor of 1.5-5.0.

[0017] In some embodiments of the present application, the central control module controls the multi-degree-of-freedom transfer robot to perform the following operations:

[0018] Based on the coordinate information, the flexible carrier film is attached to the surface of the thin-film battery cell after laser irradiation by driving the mounting head;

[0019] The thin-film battery cell is separated from the growth substrate and attached to the flexible carrier film by moving along a preset peeling trajectory;

[0020] The flexible carrier film with the attached thin-film battery cell is transferred and laminated to the corresponding bonding area of the target substrate.

[0021] In some embodiments of the present application, the preset peeling trajectory is an arc trajectory or an involute trajectory with an angle of 30° to 80° with the plane of the growth substrate, and the instantaneous speed of the multi-degree-of-freedom transfer robot during peeling is negatively related to the peeling force value fed back by the force sensor.

[0022] In some embodiments of the present application, the multi-degree-of-freedom precision transfer robot is a six-axis robot, and the end effector is further integrated with an ultraviolet light source or a hot air nozzle for activating the curing and releasing of the flexible carrier film.

[0023] In some embodiments of the present application, the central control module includes a process recipe database for storing and calling laser parameters, peeling trajectory parameters, and bonding parameters for different combinations of thin-film battery cell sizes, sacrificial layer materials, and target substrate materials.

[0024] According to the second aspect of the present application, a method for transferring thin-film gallium arsenide battery by peeling based on thermal / light regulation is also provided, which includes the following steps:

[0025] Identifying the position information of the thin-film battery cell to be peeled on the growth substrate and the bonding area on the target substrate;

[0026] According to the position information of the thin-film battery cell, a laser beam is used to scan the sacrificial layer region surrounding the battery cell to be peeled, so that the bonding force of the sacrificial layer region is reduced to below a first threshold value;

[0027] The flexible carrier film processing module provides a flexible carrier film, controls the flexible carrier film to adhere to the surface of the thin-film battery cell with a first adhesion force, and applies a peeling force along a first direction to separate the thin-film battery cell from the sacrificial layer and transfer it to the flexible carrier film, wherein the first adhesion force is greater than a first threshold.

[0028] The flexible carrier film with the thin-film battery cell attached is aligned with the bonding area on the target substrate and pressed together. At the same time, the adhesion force between the flexible carrier film and the thin-film battery cell is reduced to a second adhesion force, and the bonding force between the battery cell and the bonding area is increased to be greater than the second adhesion force, thus completing the transfer of the battery cell to the target substrate.

[0029] In some embodiments of the present invention, the first direction is an arc or involute direction with an angle of 30° to 80° to the growth substrate plane, and the peeling force is monitored in real time during the peeling process, and the peeling force is maintained within a preset safe range by adjusting the peeling angle and / or speed.

[0030] The beneficial effects of this invention are as follows: This invention uses a visual positioning module to accurately identify and locate the positions of the battery cells and the target substrate, and provides coordinate information to the central control module. This ensures that the laser stripping module can scan the irradiated sacrificial layer with high precision and selectivity, achieving non-destructive weakening stripping. The laser stripping process uses selective scanning, avoiding damage to the functional layer and improving processing uniformity. The flexible carrier film processing module, through the loading force sensor and the mounting head of the roller pressing assembly, can reliably pick up the stripped film, preventing micro-cracks or damage caused by thermal deformation or excessive stress. The heating function of the target substrate carrier stage further enhances the adhesion between the film and the target substrate, and the controlled heat treatment promotes the stable formation of bonding strength, making it particularly suitable for applications requiring high-reliability connections. This invention integrates visual positioning, thermal / optical control, flexible carrier film processing, and precision mechanical transfer. It not only avoids the pollution and low efficiency problems of wet chemical etching, but also utilizes the combined effect of light and heat to weaken the stripping layer, and combines a mechanical platform to complete the non-destructive picking and reliable transfer of the film, ensuring the high efficiency of the stripping process, thereby improving yield and environmental friendliness. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1This is a schematic diagram of the structure of the thin-film gallium arsenide battery stripping and transfer system based on thermal / optical modulation in an embodiment of the present invention;

[0033] Figure 2 This is a flowchart illustrating the steps of the thin-film gallium arsenide battery stripping and transfer method based on thermal / optical modulation in an embodiment of the present invention. Detailed Implementation

[0034] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0035] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0037] Example 1

[0038] like Figure 1 The thermal / optical controlled thin-film gallium arsenide cell lift-off and transfer system shown includes:

[0039] The growth substrate support stage is used to support and fix the growth substrate on which thin-film battery cells are grown. There is a sacrificial layer between the growth substrate and the thin-film battery cells. The sacrificial layer fixes the thin-film battery on the growth substrate. The sacrificial layer is destroyed by laser to reduce the bonding force between the thin-film battery and the growth substrate. Then, the thin-film battery is separated from the growth substrate by tearing.

[0040] The target substrate support stage is used to support and fix the target substrate. The target substrate has a bonding area. The target substrate support stage has a built-in heater for heat treatment of the target substrate during the transfer and pressing of the thin film battery cells. After the thin film battery is transferred to the target substrate, it is necessary to press the thin film battery and the target substrate together. The heater can enhance the bonding force between the two.

[0041] The visual positioning module is used to identify and locate the thin-film battery cells on the growth substrate and the bonding area on the target substrate, and output coordinate information. It should be noted that the visual positioning module can take many forms, such as a CCD camera, a line scan camera, or other structures capable of visual recognition. It can also analyze and calculate the images acquired by the camera through image processing algorithms or other software algorithms to obtain more specific coordinate information.

[0042] The laser lift-off module selectively scans and irradiates the sacrificial layer surrounding the thin-film battery cell based on coordinate information. By selectively irradiating the sacrificial layer, laser lift-off effectively reduces the adhesion between the thin-film battery and the growth substrate without complete removal, creating more stable processing conditions for subsequent mechanical pickup and precise transfer. This reduces thermal damage to the functional layer caused by the laser and avoids problems such as film floating, deformation, or runaway that may occur with complete removal, ensuring the stability of the thin-film battery cell on the growth substrate and improving the controllability of the pickup and transfer process. The high precision and selective weakening of adhesion by laser lift-off ensure the uniformity and reliability of large-area thin-film battery lift-off, improving overall production efficiency. Compared to traditional chemical etching processes, this invention does not rely on highly corrosive chemicals, avoiding environmental problems caused by waste liquid treatment, simplifying the process flow, and achieving higher automation and flexibility.

[0043] The flexible carrier film processing module, including an unwinding mechanism, a rewinding mechanism, a tension controller, and a mounting head comprising a force sensor and a roll forming assembly, is used to attach the flexible carrier film to the surface of the thin-film battery cell. By precisely controlling the attachment, tension, and rewinding processes of the flexible carrier film, high efficiency and reliability are achieved in the peeling, picking, transfer, and release processes of the thin-film battery cell. Using the flexible carrier film as a temporary carrier, the laser-peeled thin-film battery cell is safely picked up from the growth substrate and protected, preventing cracking, warping, or damage caused by stress concentration or deformation during transport. Simultaneously, the mounting head with force sensors and a roll forming assembly ensures uniform adhesion and precise control of the adhesion force between the carrier film and the thin film, avoiding excessive mechanical stress on the film structure. Dynamic tension control of the unwinding and rewinding mechanisms ensures that the carrier film remains flat throughout the operation, preventing wrinkles and loosening. During transfer to the target substrate, a flexible release method achieves precise bonding of the thin-film battery, increasing adhesion and transfer accuracy, while also improving the automation level of the entire process. Compared to traditional manual operation methods, the flexible carrier film processing module significantly improves the protection performance, efficiency, and precision during the peeling and transfer of thin-film batteries, and can better meet the needs of large-scale industrial production of flexible electronics and solar cells.

[0044] The central control module is connected to the visual positioning module, the laser stripping module, and the flexible carrier film processing module, respectively. It is used to coordinate and control the collaborative operation of the various modules of the system and generate laser scanning path control commands.

[0045] The multi-degree-of-freedom transfer robot includes an end effector with an integrated mounting head. A central control module controls the robot to peel off thin-film battery cells from a growth substrate and transfer them to a target substrate for bonding. Its flexible multi-degree-of-freedom motion capability enables peeling and transfer operations in complex paths. The mounting head at its end integrates force sensors and rolling components, allowing real-time monitoring of mechanical changes during peeling and adhesion. Feedback is used to adjust the peeling angle and movement speed, ensuring that the peeling and transfer forces of the thin-film battery remain within a safe range, preventing damage to the functional layers.

[0046] This invention utilizes a visual positioning module to accurately identify and locate the positions of battery cells and the target substrate, providing coordinate information to the central control module. This ensures that the laser stripping module can scan the irradiation sacrificial layer with high precision and selectivity, achieving non-destructive weakening stripping. The laser stripping process employs selective scanning, avoiding damage to the functional layer and improving processing uniformity. The flexible carrier film processing module, through a force sensor and a roller pressing assembly's mounting head, enables reliable pickup of the stripped film, preventing micro-cracks or damage caused by thermal deformation or excessive stress. The heating function of the target substrate support stage further enhances the adhesion between the film and the target substrate, promoting stable bonding strength formation through controlled heat treatment, making it particularly suitable for applications requiring high-reliability connections. This invention integrates visual positioning, thermal / optical control, flexible carrier film processing, and precision mechanical transfer. It not only avoids the pollution and low efficiency problems of wet chemical etching but also utilizes the combined effect of light and heat to weaken the stripping layer, combined with a mechanical platform to complete non-destructive pickup and reliable transfer of the film, ensuring high efficiency in the stripping process, thereby improving yield and environmental friendliness.

[0047] The laser lift-off module effectively weakens the adhesion between the thin-film battery cells and the growth substrate by selectively irradiating the sacrificial layer, thus providing reliable support for subsequent mechanical pickup and transfer. Traditional laser lift-off processes typically rely solely on the high energy density of the laser for direct lift-off, which not only requires extremely precise control of the laser power but also easily damages the functional layers of the thin film. Because thermal stress cannot be effectively relieved, the peeled film is prone to cracking or warping due to thermal shock, reducing yield. In large-area lift-off, due to the non-uniformity of energy distribution, existing technologies struggle to ensure consistency in the lift-off process. The laser lift-off module includes a laser, a scanning galvanometer that controls the laser beam emitted by the laser to perform pattern scanning in the XY plane, and a coaxial cooling component for localized cooling of the growth substrate during laser scanning. The laser provides precisely controlled laser beam energy and wavelength, and the scanning galvanometer enables the laser beam to flexibly perform high-precision patterned scanning in the XY plane, thereby directionally weakening the adhesion according to the layout and shape of the thin-film battery cells and the sacrificial layer, avoiding unnecessary effects on non-target areas. Precise path planning enables the peeling of complex geometries, effectively improving peeling uniformity and avoiding unnecessary energy waste. The coaxial cooling component integrated during laser scanning dynamically cools localized areas, promptly removing excess heat and reducing the risk of thermal damage to the thin film functional layer and surrounding materials from laser irradiation. This also minimizes the impact of thermal stress on film integrity, further ensuring the quality of the peeled film.

[0048] Slightly higher laser energy may damage the functional layer of the battery, while slightly lower energy may result in incomplete peeling. Inaccurate scanning paths can lead to uneven peeling or even cracks at the film edges, ultimately affecting product yield and performance stability. The laser wavelength is 248nm, 355nm, or 532nm. The laser energy density is below the damage threshold of the gallium arsenide epitaxial layer in the thin-film battery cell but above the decomposition threshold of the sacrificial layer material. The scanning path is a closed loop 1-10μm along the inner side of the battery cell boundary. This invention, by precisely selecting the laser wavelength, uses a specific wavelength to target the sacrificial layer around the thin-film battery cell, effectively absorbing and converting energy to bring the sacrificial layer material to the decomposition threshold while remaining below the damage threshold of the gallium arsenide epitaxial layer. This not only ensures selectivity in the peeling process, avoiding any thermal or optical damage to the core functional layer, but also optimizes the energy utilization efficiency of the laser, making the peeling process more precise and safer. Setting the scanning path as a closed loop 1-10μm along the inner side of the battery cell boundary maximizes the integrity of the film boundary, preventing structural damage or displacement due to improper laser operation.

[0049] After laser ablation, the thin-film battery needs to be separated from the growth substrate. To ensure a more stable ablation process, the flexible polymer carrier film in the flexible carrier film processing module is either a UV-curable adhesive film or a thermosetting release adhesive film. The adhesion of the flexible polymer carrier film to the battery layer in its uncured state is crucial. The residual bonding force between the sacrificial layer and the battery layer after laser irradiation The following conditions must be met: ,in A safety factor of 1.2 to 3.0 is provided. This ensures that the carrier film can stably pick up the thin-film battery cell without applying excessive external force, avoiding film deformation or damage to the functional layer structure due to peel stress. The adhesion of the flexible polymer carrier film to the battery layer after curing is also considered. The final bonding force between the battery layer and the bonding region of the target substrate The following conditions must be met: ,in With a peel coefficient of 1.5 to 5.0, it provides ample assurance for subsequent precise release and reliable bonding, preventing film residue on the carrier film and ensuring a strong and uniform bond between the battery and the target substrate. The carrier film uses UV-curable adhesive film or thermosetting release adhesive film. By precisely controlling the adhesion force under different conditions, safe pickup and accurate transfer of thin-film batteries are achieved, avoiding the high damage and instability in the pickup and transfer process caused by uncontrollable adhesion force in traditional methods.

[0050] In some embodiments of the present invention, the central control module controls the multi-degree-of-freedom transfer robot to perform the following operations:

[0051] Based on coordinate information, the mounting head is driven to attach a flexible carrier film to the surface of the thin-film battery cell after laser irradiation.

[0052] The thin-film battery cells are separated from the growth substrate and attached to the flexible carrier film by moving along a preset peeling trajectory.

[0053] The flexible carrier film with the thin-film battery cells attached is transferred and pressed onto the corresponding bonding area of ​​the target substrate.

[0054] The central control module controls the operations performed by the multi-degree-of-freedom transfer robot, ensuring the stability and precision of the thin-film battery cells during peeling, picking, transfer, and lamination processes, effectively avoiding film damage caused by uneven mechanical stress or accidental misalignment. The introduction of the central control module not only significantly improves the automation level of the entire peeling-transfer process but also fully optimizes the overall performance of the thin-film battery. By coordinating the multi-degree-of-freedom transfer robot, complex peeling and lamination operations are completed smoothly under precise control, improving process safety and efficiency. Precise peeling trajectories and seamless docking with the target substrate ensure high-quality bonding of the thin-film battery and improved yield. The central control module, combined with the multi-degree-of-freedom robot, possesses strong adaptability, allowing for flexible handling of thin-film batteries and target substrates of different sizes and materials—an advantage unmatched by traditional methods.

[0055] Improper peeling angle and speed can lead to mechanical damage to the functional layers of thin-film batteries, such as warping, stretching, or cracking. This risk is particularly pronounced when dealing with complex or extremely thin film materials. Relying on fixed mechanical operation paths makes it difficult to adapt to real-time feedback, hindering precise optimization of mechanical stress control during peeling. This can result in incomplete peeling, edge residue, or uneven separation, reducing product yield and quality consistency. The preset peeling trajectory is an arc-shaped or involute trajectory at an angle of 30° to 80° to the growth substrate plane, and the instantaneous speed of the multi-degree-of-freedom transfer robot during peeling is negatively correlated with the peeling force value fed back by the force sensor. During peeling, the arc-shaped or involute trajectory planning minimizes stress concentration as the film leaves the growth substrate, maintaining the integrity and uniformity of the film edges. The arc-shaped trajectory allows for gradual stress release, while the involute trajectory provides a smooth mechanical transition, effectively avoiding the negative impact of abrupt stress changes on the film structure. The multi-degree-of-freedom transfer robot adjusts its instantaneous speed during peeling in real time based on the peeling force value fed back by the force sensor, making the two inversely correlated. This ensures that when the peeling force increases, the robot automatically reduces its speed to prevent the film from being damaged due to excessive force; when the peeling force decreases, the robot can accelerate appropriately to improve peeling efficiency, enhance the accuracy and stability of the operation, reduce the risk of damage during the peeling of thin-film batteries, and effectively expand its adaptability to different thin-film materials and process requirements.

[0056] In some embodiments of the present invention, the multi-degree-of-freedom precision transfer robot is a six-axis robot, and the end effector also integrates an ultraviolet light source or hot air nozzle for activating the curing and release of the flexible carrier film. Through the integrated ultraviolet light source or hot air nozzle, real-time curing and controlled release of the flexible carrier film can be achieved, making the film transfer process smoother and eliminating the need to pause or add extra steps to achieve a firm bond or safe release operation. The high flexibility and precise positioning of the six-axis robot ensure that carrier film processing and film positioning are completed quickly and stably without affecting the integrity of the film or target substrate, greatly improving process efficiency.

[0057] The varying sizes, sacrificial layer materials, and target substrate materials of different thin-film battery cells necessitate frequent adjustments to the manufacturing process. This not only increases production complexity and uncertainty but also raises the risk of errors, leading to reduced production efficiency and difficulty in ensuring quality stability. Furthermore, manually adjusting parameter combinations is time-consuming and labor-intensive, making it difficult to maintain flexibility and efficiency in large-scale production. In some embodiments of this invention, the central control module includes a process recipe database for storing and retrieving combinations of laser parameters, peeling trajectory parameters, and bonding parameters for different thin-film battery cell sizes, sacrificial layer materials, and target substrate materials. When different sizes or materials need to be converted during production, the central control module can quickly access and apply pre-optimized parameter combinations, thereby automatically adjusting the processing path and process settings without human intervention. This not only accelerates response speed and production flexibility but also reduces quality fluctuations caused by human error.

[0058] According to a second aspect of the present invention, a method for peeling and transferring thin-film gallium arsenide solar cells based on thermal / optical modulation is also provided, such as... Figure 2 As shown, the steps include:

[0059] S10: Identify the location information of the thin-film battery cells to be peeled off on the growth substrate and the bonding area on the target substrate;

[0060] S20: Based on the position information of the thin-film battery cell, control the laser beam to scan the sacrificial layer region surrounding the battery cell to be peeled off, so that the adhesion of the sacrificial layer region decreases to below the first threshold.

[0061] S30: The flexible carrier film processing module provides a flexible carrier film, controls the flexible carrier film to adhere to the surface of the thin film battery cell with a first adhesion force, and applies a peeling force along a first direction to separate the thin film battery cell from the sacrificial layer and transfer it to the flexible carrier film. The first adhesion force is greater than a first threshold.

[0062] S40: Align the flexible carrier film with the thin-film battery cell attached to the bonding area on the target substrate and press them together. At the same time, reduce the adhesion force between the flexible carrier film and the thin-film battery cell to the second adhesion force and increase the bonding force between the battery cell and the bonding area to be greater than the second adhesion force, thus completing the transfer of the battery cell to the target substrate.

[0063] By cleverly combining thermal / light regulation and meticulously adjusting the adhesion and bonding forces at different operational stages, the damage and instability issues of thin-film batteries during the transfer process have been solved. Automation and precise control have improved production efficiency and reduced human error and uncertainty that depend on the process. The controllable peeling and transfer process not only improves the quality consistency of the final product but also significantly reduces the complexity of production operations, providing strong technical support and guarantee for the large-scale industrial production of flexible electronics and solar cells.

[0064] In some embodiments of the present invention, the first direction is an arcuate or involute direction forming an angle of 30° to 80° with the growth substrate plane. The peeling force is monitored in real time during the peeling process, and the peeling angle and / or speed are adjusted to maintain the peeling force within a preset safety range. This effectively improves the force transmission method during peeling, allowing stress to be distributed more evenly on the film surface, reducing local stress concentration, and smoothly releasing the internal stress generated during peeling. This reduces the risk of mechanical damage to the functional layer. By monitoring the peeling force in real time, the system can precisely adjust the peeling angle and / or speed to maintain the peeling force within a preset safety range. This instant adjustment capability ensures the stability and safety of the peeling process, further protecting the integrity of the film.

[0065] Example 2

[0066] A 4-inch GaAs growth substrate with a thin-film gallium arsenide (GaAs) solar cell array is placed on a loading stage. A flexible polyimide target substrate coated with pre-coated thermosetting adhesive is mounted on a target substrate support stage and fixed by vacuum adsorption. The high-resolution camera of the visual positioning module takes pictures of the high-precision alignment marks on the two substrates, establishes a global coordinate system and a local coordinate mapping, and achieves a positioning accuracy better than ±3μm.

[0067] The central control module retrieves the process formula and sets the laser parameters for the current AlAs sacrificial layer to a wavelength of 355 nm, a pulse frequency of 30 kHz, and an energy density of 150 mJ / cm². Based on the cell contour coordinates provided by the vision positioning module, the scanning galvanometer of the laser lift-off module controls the laser beam to perform a closed-loop scan along the inner 5 μm of the cell boundary. The coaxial cooling system blows out low-temperature nitrogen gas to prevent heat accumulation and damage to the cell. After this step, the sacrificial layer adhesion force F2 in the scanned area decreases from an initial >1 N / cm² to approximately 0.3 N / cm².

[0068] A multi-degree-of-freedom precision transfer robot moves above the growth substrate, and its end effector draws out the UV-release adhesive film from the unwinding mechanism of the flexible carrier film processing module. The initial adhesion force F1 is approximately 1.0 N / cm², satisfying F1 > 1.2 × F2. The mounting head rolls and attaches the adhesive film to the surface of the target battery cell with a constant pressure of 0.1 MPa, and a miniature force sensor ensures uniform and bubble-free attachment.

[0069] The robot performs the peeling action. The control program presets the initial peeling angle to be 60°, the initial speed to be 10 mm / s, and the target peeling force upper limit to be 0.5 N / cm. The robot's end effector moves along an involute trajectory. During this process, a miniature force sensor provides real-time feedback on the peeling force f. The central control module dynamically adjusts the robot's movement based on the value of f. If f is close to 0.5 N / cm, the peeling angle is slightly increased or the speed is decreased; if f is too small, the speed is appropriately increased to improve efficiency, ensuring that the peeling process is always under low stress.

[0070] The robot carries the carrier film with the attached battery film to the target substrate. The vision system performs a second fine alignment. After alignment, the robot presses the film onto the predetermined bonding area of ​​the target substrate at a pressure of 0.2 MPa. The target substrate support stage is rapidly heated to 180°C, and after 30 seconds of pressing, a 365nm UV LED array integrated on the end effector is turned on to irradiate the flexible carrier film for 3 seconds.

[0071] Heat activates the adhesive on the target substrate, causing it to flow, wet, and form a strong bond with the back of the battery. The bonding force F4 rapidly increases to greater than 2.0 N / cm². UV irradiation causes the adhesive layer of the flexible carrier film to undergo a curing reaction, and its adhesion force F3 decreases to about 0.2 N / cm². Since F4 > k2×F3, the battery film is released and bonded to the target substrate.

[0072] The robot moves away smoothly, the solidified flexible carrier film is retrieved by the winding mechanism, the central control module updates the coordinates, and the command system begins processing the next battery cell.

[0073] This system and method achieve automated, low-damage, and high-precision transfer of thin-film gallium arsenide (GaAs) solar cells to flexible substrates. Experimental data comparison shows that the solar cell array using this invention exhibits over 70% lower dispersion in its electrical performance parameters compared to traditional wet processing, providing a reliable equipment and process solution.

[0074] Those skilled in the art should understand that this invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to this invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A thin-film gallium arsenide solar cell stripping and transfer system based on thermal / optical modulation, characterized in that, include: A growth substrate support stage is used to support and fix a growth substrate on which thin-film battery cells are grown, and a sacrificial layer is provided between the growth substrate and the thin-film battery cells. A target substrate support stage is used to support and fix a target substrate, the target substrate having a bonding area, and the target substrate support stage has a built-in heater for heat treatment of the target substrate during the transfer and pressing of the thin-film battery cell. A visual positioning module is used to identify and locate the thin-film battery cells on the growth substrate and the bonding area on the target substrate, and output coordinate information; The laser stripping module is used to emit a laser beam to selectively scan and irradiate the sacrificial layer around the periphery of the thin-film battery cell according to the coordinate information. The flexible carrier film processing module includes an unwinding mechanism, a winding mechanism, a tension controller, and a mounting head including a force sensor and a roll forming assembly, for attaching the flexible carrier film to the surface of the thin-film battery cell. The central control module is connected to the visual positioning module, the laser stripping module, and the flexible carrier film processing module, respectively, and is used to coordinate and control the collaborative operation of the various modules of the system and generate laser scanning path control commands. A multi-degree-of-freedom transfer robot includes an end effector integrated with the mounting head. The central control module controls the multi-degree-of-freedom transfer robot to peel the thin-film battery cell from the growth substrate and transfer it to the target substrate for bonding.

2. The thin-film gallium arsenide solar cell stripping and transfer system based on thermal / optical modulation according to claim 1, characterized in that, The laser lift-off module includes a laser, a scanning galvanometer for controlling the laser beam emitted by the laser to perform pattern scanning in the XY plane, and a coaxial cooling component for locally cooling the growth substrate during laser scanning.

3. The thin-film gallium arsenide solar cell stripping and transfer system based on thermal / optical modulation according to claim 2, characterized in that, The wavelength of the laser is 248nm, 355nm or 532nm, the laser energy density is lower than the damage threshold of the gallium arsenide epitaxial layer of the thin-film battery cell and higher than the decomposition threshold of the sacrificial layer material, and the scanning path is a closed loop path 1-10μm along the inner side of the battery cell boundary.

4. The thin-film gallium arsenide solar cell stripping and transfer system based on thermal / optical modulation according to claim 1, characterized in that, The flexible polymer carrier film in the flexible carrier film processing module is a UV-curable adhesive film or a thermosetting release adhesive film. The adhesion of the flexible polymer carrier film to the battery layer in its uncured state is... The residual bonding force between the sacrificial layer and the battery layer after laser irradiation The following conditions must be met: ,in The safety factor is 1.2 to 3.0; the adhesion force of the flexible polymer carrier film to the battery layer after curing. The final bonding force between the battery layer and the bonding region of the target substrate The following conditions must be met: ,in The stripping coefficient is 1.5 to 5.

0.

5. The thin-film gallium arsenide solar cell stripping and transfer system based on thermal / optical modulation according to claim 1, characterized in that, The central control module controls the multi-degree-of-freedom transfer robot to perform the following operations: Based on the coordinate information, the mounting head is driven to attach the flexible carrier film to the surface of the thin-film battery cell after laser irradiation. The thin-film battery cell is separated from the growth substrate and attached to the flexible carrier film by moving along a preset peeling trajectory. The flexible carrier film with the attached thin-film battery cell is transferred and pressed onto the corresponding bonding area of ​​the target substrate.

6. The thin-film gallium arsenide solar cell stripping and transfer system based on thermal / optical modulation according to claim 5, characterized in that, The preset peeling trajectory is an arc-shaped trajectory or an involute trajectory with an angle of 30° to 80° to the plane of the growth substrate, and the instantaneous speed of the multi-degree-of-freedom transfer robot when performing peeling is negatively correlated with the peeling force value fed back by the force sensor.

7. The thin-film gallium arsenide solar cell stripping and transfer system based on thermal / optical modulation according to claim 1, characterized in that, The multi-degree-of-freedom precision transfer robot is a six-axis robot, and the end effector is also integrated with an ultraviolet light source or hot air nozzle for activating the curing and release of the flexible carrier film.

8. The thin-film gallium arsenide solar cell stripping and transfer system based on thermal / optical modulation according to claim 1, characterized in that, The central control module includes a process recipe database for storing and retrieving combinations of laser parameters, peeling trajectory parameters, and bonding parameters for different thin-film battery cell sizes, sacrificial layer materials, and target substrate materials.

9. A method for peeling and transferring thin-film gallium arsenide solar cells based on thermal / optical modulation, characterized in that, The method using the thermally / optically controlled thin-film gallium arsenide cell stripping and transfer system as described in any one of claims 1 to 8 includes the following steps: Identify the location information of the thin-film battery cells to be peeled off on the growth substrate and the bonding area on the target substrate; Based on the position information of the thin-film battery cell, the laser beam is controlled to scan the sacrificial layer region surrounding the battery cell to be peeled off, so that the adhesion of the sacrificial layer region is reduced to below a first threshold. The flexible carrier film processing module provides a flexible carrier film, controls the flexible carrier film to adhere to the surface of the thin-film battery cell with a first adhesion force, and applies a peeling force along a first direction to separate the thin-film battery cell from the sacrificial layer and transfer it to the flexible carrier film, wherein the first adhesion force is greater than a first threshold. The flexible carrier film with the thin-film battery cell attached is aligned with the bonding area on the target substrate and pressed together. At the same time, the adhesion force between the flexible carrier film and the thin-film battery cell is reduced to a second adhesion force, and the bonding force between the battery cell and the bonding area is increased to be greater than the second adhesion force, thus completing the transfer of the battery cell to the target substrate.

10. The thin-film gallium arsenide solar cell stripping and transfer system based on thermal / optical modulation according to claim 9, characterized in that, The first direction is an arc or involute direction with an angle of 30° to 80° to the growth substrate plane, and the peeling force is monitored in real time during the peeling process, and the peeling force is maintained within a preset safe range by adjusting the peeling angle and / or speed.

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