Efficient reworking method and device for BC battery coating defective products
By combining infrared thermal imager and fiber optic spectrometer detection with laser pretreatment, organic solvents, and ultrasonic array film removal, the problem of severe silicon wafer damage and low utilization rate of defective BC battery coating products was solved, achieving efficient rework and cost reduction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SICHUAN GOKIN SOLAR TECHNOLOGY CO LTD
- Filing Date
- 2026-02-24
- Publication Date
- 2026-05-26
AI Technical Summary
Existing technologies for handling defective BC battery coatings suffer from problems such as low silicon wafer utilization, severe damage, and significant safety hazards. Traditional methods are unable to achieve selective and gentle film peeling.
Defective areas were identified by a combination of infrared thermal imager and fiber optic spectrometer. Laser pretreatment was used to weaken the bonding force. The film was removed by a combination of heated organic mixed solvent and multi-band ultrasonic array. The silicon wafers were then repaired through multi-stage cleaning to ensure that the quality of the silicon wafers met the requirements for reintroduction into the production line.
It achieves selective and gentle peeling of defective films, allowing silicon wafers to be reused on the production line with extremely low loss, improving material utilization and production efficiency, and reducing production costs.
Smart Images
Figure CN122094221A_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of BC battery production technology, and specifically relates to an efficient rework method and apparatus for defective BC battery coating products. Background Technology
[0002] In the large-scale production of BC batteries, the preparation of silicon nitride antireflective coatings by chemical vapor deposition (PECVD) is a key process to ensure the photoelectric conversion efficiency of the batteries. However, due to various factors such as fluctuations in process parameters, malfunctions in production equipment, and defects in incoming materials, a certain proportion of defective coated products are inevitable. If the silicon nitride film covering the surface of these defective products is not effectively treated, it cannot be directly returned to the previous processes such as diffusion and etching for reprocessing, resulting in a significant waste of silicon wafer resources.
[0003] Currently, the traditional rework methods for defective BC battery coatings in the industry are mainly divided into two categories: one is physical grinding or polishing, which easily causes uneven silicon wafer thickness, severe surface damage, and generates a large amount of waste, significantly reducing silicon wafer utilization; the other is highly corrosive wet etching, represented by hot phosphoric acid etching. While etching the silicon nitride film layer, it also causes severe corrosion to the underlying silicon substrate, resulting in a single wafer thinning of up to several micrometers. This cannot meet the stringent requirements of BC batteries for silicon wafer thickness uniformity and may even directly render the silicon wafer unusable. In addition, highly corrosive wet etching requires the use of large amounts of high-temperature concentrated acid, which generates highly polluting waste liquid containing phosphorus and fluorine. This not only has high treatment costs but also poses significant operational safety hazards. Furthermore, for silicon wafers that have already formed a PN junction, the strong corrosion will destroy the junction structure, leading to permanent failure of the battery's electrical performance. Summary of the Invention
[0004] In view of this, the purpose of this application is to provide an efficient rework method and apparatus for defective BC battery coatings, which can selectively and gently peel off the defective coating, so that the silicon wafers can be put back into the production line with extremely low loss and improve material utilization.
[0005] In a first aspect, this application provides an efficient rework method for defective BC battery coating products, the method comprising the following steps: Information is entered into the coating process of BC battery production to identify defective silicon wafers. The silicon wafer is inspected using a combination of infrared thermal imager and fiber optic spectrometer to determine the type, location, and severity of defective areas and generate a digital map. Laser irradiation pretreatment is performed on severely defective areas of the silicon wafer in the digital map to weaken the adhesion between the film layer and the silicon substrate; The pre-treated silicon wafer is delaminated using an organic mixed solvent heated to a set temperature in conjunction with a multi-band ultrasonic array; wherein the organic mixed solvent includes a main solvent and a co-solvent, the main solvent being one or more of DMSO, NMP, and DMF, and the co-solvent being an alcohol; The silicon wafers after film removal are sequentially subjected to primary buffer rinsing, adaptive buffer etching, secondary ultrasonic cleaning and repair, dehydration and drying to remove residual silicon oxides on the silicon wafer surface and repair the silicon surface. The dried silicon wafers are sorted into qualified wafers and scrap wafers; the qualified wafers are returned to BC cell production.
[0006] In some embodiments, defective silicon wafers generated during the coating process in BC battery production are transported via baskets; the information entered includes the type of silicon wafer, and different types of silicon wafers correspond to different pretreatment, film removal, and etching parameters.
[0007] In some embodiments, the silicon wafer is first scanned comprehensively using an infrared thermal imager. The contrast formed in the thermal image by the temperature difference caused by uneven film thickness or contamination is used to locate the macroscopic defect area. Then, the micro-area reflectance spectrum of the located macroscopic defect area is measured by a fiber optic spectrometer integrated on the infrared thermal imager. By analyzing the spectral curve, the type, location and severity of the defect area are determined.
[0008] In some embodiments, the location of severely defective areas is determined from the digital map, and a short-pulse laser is used to scan and irradiate the areas according to laser parameters matched to the defect type, thereby weakening the adhesion between the film and the silicon substrate; the laser energy density in the laser parameters is higher than the silicon nitride film ablation threshold but lower than the silicon damage threshold.
[0009] In some embodiments, the process of removing the film from the pretreated silicon wafer using an organic mixed solvent heated to a set temperature in conjunction with a multi-band ultrasonic array includes the following steps: The pretreated silicon wafer carrier basket is transferred into the preheated organic solvent dynamic circulation stripping main cavity; the basket rotates within the organic solvent dynamic circulation stripping main cavity. Depending on the type of silicon wafer, the organic mixed solvent in the main cavity is heated to a set temperature and forms a uniform upward laminar flow that washes over the silicon wafer surface. Ultrasonic waves emitted by a multi-band ultrasonic array are used to assist the penetration of the organic mixed solvent. The organic mixed solvent containing film debris is filtered and recycled.
[0010] In some embodiments, the sequential treatment of the silicon wafer after film removal, including primary buffer rinsing, adaptive buffer etching, secondary ultrasonic cleaning and repair, and dehydration and drying, comprises the following steps: After the film is removed, the silicon wafer is transferred to the first-level buffer rinsing chamber and rinsed with deionized water overflow to remove residual solvent and loose particles. After overflow rinsing, the silicon wafer is transferred into an adaptive buffer etching tank and etched using a fluoride buffer solution to remove residual silicon oxide; the fluoride buffer solution is HF or a buffer solution of NH4F and HF. The etched silicon wafer is transferred into a secondary ultrasonic cleaning chamber, where SC-1 standard cleaning solution is used in conjunction with mega-sonic waves to clean it, remove residual organic matter and repair the silicon surface. The cleaned silicon wafers are transferred into the dehydration and drying chamber, where they are first dehydrated by isopropyl alcohol (IPA) vapor and then dried by nitrogen hot air.
[0011] In some embodiments, the dried silicon wafers are subjected to automatic optical inspection and electrical performance evaluation, and are sorted into qualified wafers and scrap wafers according to the inspection results; silicon wafers with no visible defects on the surface and minority carrier lifetime decay less than a set threshold are classified as qualified wafers.
[0012] Secondly, this application also provides an efficient rework device for defective BC battery coatings, the device comprising: The information entry module is used to enter information about defective silicon wafers generated during the coating process in BC battery production. The refined inspection module is used to perform joint inspection of silicon wafers using an infrared thermal imager and a fiber optic spectrometer to determine the type, location, and severity of defective areas and generate a digital map. The laser preprocessing module is used to perform laser irradiation preprocessing on severely defective areas of the silicon wafer in the digital map, in order to weaken the adhesion between the film layer and the silicon substrate. An organic stripping module is used to remove the film from a pre-treated silicon wafer using an organic mixed solvent heated to a set temperature in conjunction with a multi-band ultrasonic array; wherein the organic mixed solvent includes a main solvent and a co-solvent, the main solvent being one or more of DMSO, NMP, and DMF, and the co-solvent being an alcohol; The multi-stage cleaning and repair module is used to sequentially perform first-stage buffer rinsing, adaptive buffer etching, second-stage ultrasonic cleaning and repair, dehydration and drying on the silicon wafer after film removal, in order to remove residual silicon oxide on the silicon wafer surface and repair the silicon surface. The sorting module is used to separate the dried silicon wafers into qualified wafers and scrap wafers; among them, the qualified wafers are returned to BC cell production.
[0013] Thirdly, this application also provides an electronic device, including: a processor, a memory, and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor communicates with the memory via the bus, and when the machine-readable instructions are executed by the processor, the steps of the efficient rework method for defective BC battery coating products described in any of the first aspects are executed.
[0014] Fourthly, this application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, performs the steps of the efficient rework method for defective BC battery coating products as described in any one of the first aspects.
[0015] This application describes an efficient rework method for defective BC battery coating products. The method involves: recording information on defective silicon wafers generated during the coating process in BC battery production; using a combined infrared thermal imager and fiber optic spectrometer to detect the silicon wafers, determining the type, location, and severity of defective areas, and generating a digital map; pre-treating severely defective areas of the silicon wafers in the digital map with laser irradiation to weaken the adhesion between the coating layer and the silicon substrate; removing the coating from the pre-treated silicon wafers using an organic mixed solvent heated to a set temperature in conjunction with a multi-band ultrasonic array; sequentially performing a primary buffer rinsing, adaptive buffer etching, a secondary ultrasonic cleaning and repair, dehydration, and drying treatments to remove residual silicon oxide and repair the silicon surface; sorting the dried silicon wafers into qualified wafers and scrap wafers; and returning the qualified wafers to BC battery production. By precisely detecting and locating silicon substrates, performing targeted pretreatment, gently organic peeling, and adaptive cleaning and repair, silicon wafers can be reused on the production line with minimal loss, significantly reducing production costs and improving material utilization and overall economic efficiency of the production line. Attached Figure Description
[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 A flowchart of the efficient rework method for defective BC battery coating products described in this application embodiment is shown; Figure 2 This document illustrates a flowchart of the film removal process for a pre-treated silicon wafer according to an embodiment of this application. Figure 3This document illustrates a flowchart of the sequential processes performed on the silicon wafer after film removal, including primary buffer rinsing, adaptive buffer etching, secondary ultrasonic cleaning and repair, dehydration, and drying, according to an embodiment of this application. Figure 4 This paper shows a schematic diagram of the structure of the high-efficiency rework device for defective BC battery coating products according to an embodiment of this application; Figure 5 A schematic diagram of the structure of the electronic device described in an embodiment of this application is shown. Detailed Implementation
[0018] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the accompanying drawings in this application are for illustrative and descriptive purposes only and are not intended to limit the scope of protection of this application. Furthermore, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application illustrate operations implemented according to some embodiments of this application. It should be understood that the operations in the flowcharts may not be implemented in sequence, and steps without logical contextual relationships may be reversed or implemented simultaneously. In addition, those skilled in the art, guided by the content of this application, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts.
[0019] Furthermore, the described embodiments are merely some, not all, of the embodiments of this application. The components of the embodiments of this application described and illustrated herein can typically be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0020] It should be noted that the term "comprising" will be used in the embodiments of this application to indicate the presence of the features declared thereafter, but does not exclude the addition of other features.
[0021] To address the shortcomings of existing technologies, this application provides an efficient rework method and apparatus for defective BC battery coatings, which can selectively and gently peel off defective coatings, enabling silicon wafers to be reintroduced into the production line with extremely low loss and improving material utilization.
[0022] See the instruction manual appendix Figure 1 This application provides an efficient rework method for defective BC battery coatings, the method comprising the following steps: S1. Input information on defective silicon wafers generated during the coating process in BC battery production. S2. Use an infrared thermal imager and a fiber optic spectrometer to jointly inspect the silicon wafer, determine the type, location and severity of defective areas, and generate a digital map. S3. Perform laser irradiation pretreatment on the severely defective areas of the silicon wafer in the digital map to weaken the bonding force between the film layer and the silicon substrate; S4. Using an organic mixed solvent heated to a set temperature and in conjunction with a multi-band ultrasonic array, the pre-treated silicon wafer is delaminated; wherein, the organic mixed solvent includes a main solvent and a co-solvent, the main solvent being one or more of DMSO, NMP, and DMF, and the co-solvent being an alcohol; S5. After the film removal process, the silicon wafer is subjected to a first-level buffer rinsing, adaptive buffer etching, a second-level ultrasonic cleaning and repair, and dehydration and drying treatment in sequence to remove residual silicon oxide on the silicon wafer surface and repair the silicon surface. S6. The dried silicon wafers are sorted into qualified wafers and scrap wafers; among them, the qualified wafers are returned to BC battery production.
[0023] Specifically, step S1 mainly involves recording defective product information, which is the starting point of the efficient rework process for defective BC battery coating products. This step is used to establish a digital archive of the silicon wafers to be reworked, laying the foundation for subsequent fully automated and differentiated rework. The recorded information includes battery structure information and traceability information. The battery structure information specifies the silicon wafer type (P-type / N-type), wafer size, and original wafer thickness, which directly determine the core process parameters such as subsequent pretreatment, film removal, and etching conditions. The traceability information specifies the defective product batch number, production time, and production number, ensuring that the reworked product can be linked with the original production process to achieve full lifecycle traceability, facilitating production process optimization and quality problem localization.
[0024] In addition, this application uses a special basket to standardize the carrying of silicon wafers. The basket has positioning slots inside, and the spacing between the slots matches the size of the silicon wafers to ensure that the silicon wafers are inserted at a uniform depth without overlapping or squeezing. This avoids secondary damage and contamination of the silicon wafers during the transfer process, while ensuring high efficiency of subsequent processes.
[0025] Step S2 mainly uses a detection logic that combines macroscopic positioning and micro-area classification to accurately locate and distinguish the types of defective coated products, thereby ensuring the targeted nature of subsequent pre-processing and preventing damage to good product areas.
[0026] In one embodiment, a high-resolution infrared thermal imager is first used to perform a comprehensive scan of the silicon wafer. By utilizing the temperature difference caused by uneven film thickness or contamination in the thermal image, the location range of macroscopic defective areas is quickly located. Then, a miniature fiber optic spectrometer integrated on the scanning head of the high-resolution infrared thermal imager emits probe light to the located area and collects reflectance spectral data. Through spectral analysis, the type (such as film thickness deviation, impurity contamination, or loose film layer), location, and severity of good areas are determined. This generates a digital map with defect type markings and coordinates, providing accurate data for subsequent laser preprocessing of severely defective areas.
[0027] It should be noted that infrared imaging technology and spectral detection technology are technical means well known to those skilled in the art, and their principles and specific detection processes will not be elaborated here.
[0028] Step S3 mainly targets the severely defective areas (stubborn stains, abnormally thick film areas) marked on the digital map. Through precise parameter matching and targeted laser action, the adhesion between the defective film layer and the silicon substrate is weakened in a directional manner, so as to prevent these areas from becoming anchor points for the subsequent main peeling process. This ensures that the overall peeling process is uniform and thorough, while maximizing the protection of the good areas of the silicon wafer and its internal electrical structure.
[0029] The safety thresholds for laser parameters are defined based on the silicon wafer type and defect type. In this embodiment, a short-pulse 355nm ultraviolet laser is used. The laser beam is precisely irradiated onto the severely defective area through a galvanometer system. By precisely controlling the laser energy density (slightly higher than the silicon nitride film ablation threshold and much lower than the silicon damage threshold), the adhesion of the film in the severely defective area is reduced through photothermal and micro-explosion effects without breaking through the film layer. This creates conditions for solvent penetration and film detachment in the subsequent main stripping process.
[0030] In S4, the overall and gentle peeling of defective silicon nitride films is mainly achieved through a special organic mixed solvent.
[0031] See the instruction manual appendix Figure 2 The method of removing the film from a pretreated silicon wafer using an organic mixed solvent heated to a set temperature in conjunction with a multi-band ultrasonic array includes the following steps: S401. The pre-treated basket carrying the silicon wafer is transferred into the preheated organic solvent dynamic circulation stripping main cavity; wherein, the basket rotates in the organic solvent dynamic circulation stripping main cavity; S402. According to the type of silicon wafer, the organic mixed solvent in the main cavity of the dynamic circulating stripping organic solvent is heated to a set temperature and forms a uniform upward laminar flow to wash the surface of the silicon wafer. The ultrasonic waves emitted by the multi-band ultrasonic array are used to assist the penetration of the organic mixed solvent. The organic mixed solvent containing film debris is filtered and recycled.
[0032] In step S401, the organic solvent dynamic circulation stripping main chamber is a chemically resistant, sealed chamber with a rotating support capable of accommodating multiple baskets, ensuring the silicon wafers are arranged vertically and at intervals, and allowing for low-speed rotation controlled within the program. Preheating the organic solvent dynamic circulation stripping main chamber ensures the activity of the stripping solution and guarantees uniform film stripping. In this application, the stripping solution uses an organic mixed solvent (the main solvent is one or a mixture of DMSO / NMP / DMF; the co-solvent is an alcohol), designed to address the differences in characteristics between the silicon nitride film and the silicon substrate, ensuring that only the film is stripped without damaging the silicon.
[0033] In step S402, the prepared stripping solution is heated to a set temperature (adjustable from 60-120°C, e.g., 85°C for N-type silicon wafers and 95°C for P-type silicon wafers) by an external heater. The heated stripping solution is then injected from the bottom of the main chamber by a circulating pump, forming a uniform upward laminar flow through a porous distribution plate. This laminar flow vertically washes the silicon wafer surface, and the rotating bracket drives the basket to rotate, ensuring that each silicon wafer and each area receives uniform liquid flow. The waste liquid (including stripping solution containing film debris) flows out from the overflow port at the top of the main chamber and enters the circulation pipeline. It passes through a multi-stage precision filter to prevent the stripped solid particles from re-adhering to the silicon wafer surface. The filtered waste liquid enters the molecular sieve dehydration module to remove trace amounts of water generated during the stripping process. Finally, it returns to the heater to complete the circulation, achieving online purification and recycling of the solvent.
[0034] Furthermore, ultrasonic assistance can be used to enhance the permeability of the stripping fluid and the efficiency of membrane detachment. For example, ultrasonic waves emitted by a multi-band ultrasonic array can induce high-frequency micro-vibrations, causing fatigue damage to the membrane layer. At the same time, it can accelerate the permeation of the stripping fluid into the membrane pores, shortening the detachment time. It can also form a large number of microbubbles in the stripping fluid. The rapid generation, expansion and rupture of these bubbles generate local instantaneous high pressure, which destroys the bonding force between the membrane layer and the substrate, promoting membrane detachment.
[0035] Step S5 mainly addresses the residual impurities on the silicon wafer surface after stripping in step S4 by adaptive multi-level cleaning and repair, achieving the required cleanliness, micro-repair of damage, and dryness without residue on the silicon wafer surface, thus providing a near-original silicon wafer surface for subsequent quality re-inspection and recoating.
[0036] See the instruction manual appendix Figure 3 The process of sequentially performing primary buffer rinsing, adaptive buffer etching, secondary ultrasonic cleaning and repair, and dehydration and drying on the silicon wafer after film removal includes the following steps: S501. Transfer the silicon wafer after film removal into the first-level buffer rinsing chamber and rinse it with deionized water overflow to remove residual solvent and loose particles. S502. After overflow rinsing, the silicon wafer is transferred into an adaptive buffer etching tank and etched using a fluoride buffer solution to remove residual silicon oxide; the fluoride buffer solution is HF or a buffer solution of NH4F and HF. S503. Transfer the etched silicon wafer into the secondary ultrasonic cleaning chamber, use SC-1 standard cleaning solution, and use mega-sonic waves to clean it, remove residual organic matter and repair the silicon surface. S504. The cleaned silicon wafers are transferred into the dehydration and drying chamber, first dehydrated by isopropyl alcohol (IPA) vapor, and then dried by nitrogen hot air.
[0037] Step S501 mainly utilizes the high cleanliness of deionized water and the strong carrying capacity of overflow rinsing to quickly remove easily detachable residues adhering to the silicon wafer surface, preventing residual substances from reacting with the silicon wafer surface or forming stubborn adhesions in subsequent etching / cleaning processes.
[0038] Step S502 primarily utilizes the gentle etching properties of a low-concentration fluoride buffer solution (such as dilute HF or NH4F / HF buffer) to selectively remove residual silicon oxides from the silicon wafer surface, preventing them from affecting the adhesion of subsequent re-coating layers. Specifically, the concentration, temperature, and immersion time of the etching solution are automatically adjusted according to the silicon wafer type (e.g., for pre-existing polycrystalline silicon TBC semi-finished products, a very dilute HF solution is used for a short treatment; for wafers with only a silicon substrate, a slightly concentrated NH4F buffer solution can be used) to maximize the protection of the silicon substrate and existing electrical structures.
[0039] Step S503 primarily utilizes the synergistic effect of the chemical action of the SC-1 standard cleaning solution and the physical action of megasonic waves to thoroughly remove stubborn residues while simultaneously performing minor etching repair on the silicon wafer surface. The SC-1 standard cleaning solution (a mixture of NH4OH, H2O2, and deionized water in a specific ratio) possesses strong oxidizing and weak alkaline properties, capable of oxidizing and decomposing organic residues on the silicon wafer surface while simultaneously performing minor etching. The megasonic waves, transmitted via high-frequency pressure waves to the silicon wafer surface, accelerate the reaction between the SC-1 cleaning solution and the residual substances, while simultaneously peeling off reaction products and microparticles from the silicon wafer surface. Compared to low-frequency ultrasound, megasonic waves have more concentrated energy and no significant cavitation effect, avoiding micro-damage to the silicon wafer surface.
[0040] Step S504 mainly uses a combination of isopropyl alcohol IPA vapor dehydration and nitrogen hot air drying to thoroughly remove moisture and IPA residue from the silicon wafer surface, ensuring that the surface is free of watermarks and stains and meets the cleanliness standards.
[0041] Step S6 mainly involves online quality re-inspection and sorting to achieve a comprehensive quality assessment and precise grading of reworked silicon wafers, ensuring that qualified reworkable wafers meet the surface and electrical requirements for recoating, and preventing unqualified silicon wafers from flowing into subsequent production lines.
[0042] In one embodiment, automated optical inspection is first performed to screen silicon wafers with no visible defects and acceptable residual impurities, preventing surface defects from affecting the adhesion, uniformity, and photoelectric conversion efficiency of subsequent coatings. Then, electrical performance testing is conducted, with minority carrier lifetime as the core indicator. This directly reflects the integrity of the internal crystal structure, the integrity of electrical structures such as the PN junction, and the presence of hidden damage. Based on preset standards (e.g., minority carrier lifetime decay <8%), qualified wafers are automatically sorted into qualified and unqualified wafers. Qualified wafers are then directed back to the production process, while unqualified wafers are uniformly recycled and processed.
[0043] This application provides an efficient rework method for defective BC battery coatings. Through precise detection and positioning, targeted pretreatment, gentle organic peeling, and adaptive cleaning and repair, it greatly improves the quality and efficiency of rework while accurately protecting the silicon substrate and electrical structure.
[0044] Based on the same inventive concept, this application also provides an efficient rework device for defective BC battery coating products. Since the principle of the device in this application is similar to the efficient rework method for defective BC battery coating products described above, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be described again.
[0045] As per the instruction manual Figure 4 As shown in the illustration, this application also provides an efficient rework device for defective BC battery coatings, the device comprising: The information entry module 401 is used to enter information about defective silicon wafers generated during the coating process in the production of BC batteries. The fine inspection module 402 is used to perform joint inspection of silicon wafers using an infrared thermal imager and a fiber optic spectrometer to determine the type, location and severity of defective areas and generate a digital map. The laser preprocessing module 403 is used to perform laser irradiation preprocessing on the severely defective areas of the silicon wafer in the digital map, in order to weaken the bonding force between the film layer and the silicon substrate. The organic stripping module 404 is used to remove the film from a pre-treated silicon wafer by using an organic mixed solvent heated to a set temperature in conjunction with a multi-band ultrasonic array; wherein the organic mixed solvent includes a main solvent and a co-solvent, the main solvent being one or more of DMSO, NMP, and DMF, and the co-solvent being an alcohol; The multi-stage cleaning and repair module 405 is used to sequentially perform first-stage buffer rinsing, adaptive buffer etching, second-stage ultrasonic cleaning and repair, dehydration and drying on the silicon wafer after film removal, in order to remove residual silicon oxide on the silicon wafer surface and repair the silicon surface. The sorting module 406 is used to sort the dried silicon wafers into qualified wafers and scrap wafers; among them, the qualified wafers are returned to BC cell production.
[0046] In some embodiments, the fine detection module 402 first performs a full scan of the silicon wafer using an infrared thermal imager, and uses the temperature difference caused by uneven film thickness or contamination to form a contrast in the thermal image to locate macroscopic defective areas; then, it uses a fiber optic spectrometer integrated on the infrared thermal imager to perform micro-area reflectance spectral measurements on the located macroscopic defective areas, and determines the type, location, and severity of the defective areas by analyzing the spectral curves.
[0047] In some embodiments, the laser preprocessing module 403 determines the location of severely defective areas from the digital map and uses a short-pulse laser to scan and irradiate the area according to laser parameters matched to the defect type, thereby weakening the adhesion between the film and the silicon substrate; the laser energy density in the laser parameters is higher than the silicon nitride film ablation threshold and lower than the silicon damage threshold.
[0048] In some embodiments, the organic stripping module 404 uses an organic mixed solvent heated to a set temperature in conjunction with a multi-band ultrasonic array to remove the film from a pretreated silicon wafer, including: transferring the basket carrying the pretreated silicon wafer into a preheated organic solvent dynamic circulation stripping main cavity; wherein the basket rotates within the organic solvent dynamic circulation stripping main cavity; heating the organic mixed solvent in the organic solvent dynamic circulation stripping main cavity to a set temperature according to the silicon wafer type, forming a uniform upward laminar flow that washes over the silicon wafer surface, and using ultrasonic waves emitted by the multi-band ultrasonic array to assist the penetration of the organic mixed solvent; wherein the organic mixed solvent containing film debris is filtered and recycled.
[0049] In some embodiments, the multi-stage cleaning and repair module 405 sequentially performs a first-stage buffer rinsing, an adaptive buffer etching, a second-stage ultrasonic cleaning and repair, and dehydration and drying on the silicon wafer after film removal. This includes: transferring the silicon wafer after film removal into the first-stage buffer rinsing chamber, where it is rinsed with deionized water overflow to remove residual solvents and loose particles; transferring the overflow-rinsed silicon wafer into the adaptive buffer etching tank, where it is etched with a fluoride buffer solution to remove residual silicon oxides; the fluoride buffer solution is HF or a buffer solution of NH4F and HF; transferring the etched silicon wafer into the second-stage ultrasonic cleaning chamber, where it is cleaned with SC-1 standard cleaning solution in conjunction with megasonite to remove residual organic matter and repair the silicon surface; and transferring the cleaned silicon wafer into the dehydration and drying chamber, where it is first dehydrated with isopropyl alcohol (IPA) vapor and then dried with nitrogen hot air.
[0050] In some embodiments, the sorting module 406 performs automatic optical inspection and electrical performance evaluation on the dried silicon wafers, and sorts them into qualified wafers and scrap wafers according to the inspection results; silicon wafers with no visible defects on the surface and minority carrier lifetime decay less than a set threshold are classified as qualified wafers.
[0051] The efficient rework device for defective BC battery coating products described in this application includes: an information input module for inputting information on defective silicon wafers generated during the coating process in BC battery production; a refined detection module using an infrared thermal imager and a fiber optic spectrometer to jointly detect the silicon wafers, determine the type, location, and severity of defective areas, and generate a digital map; a laser pretreatment module using laser irradiation to pretreat severely defective areas of the silicon wafers in the digital map to weaken the adhesion between the film layer and the silicon substrate; an organic stripping module using an organic mixed solvent heated to a set temperature in conjunction with a multi-band ultrasonic array to remove the film from the pretreated silicon wafers; a multi-stage cleaning and repair module sequentially performing a first-stage buffer rinsing, adaptive buffer etching, a second-stage ultrasonic cleaning and repair, dehydration, and drying treatment on the silicon wafers to remove residual silicon oxide and repair the silicon surface; and a sorting module sorting the dried silicon wafers into qualified wafers and scrap wafers; wherein the qualified wafers are returned to BC battery production. By precisely detecting and locating silicon substrates, performing targeted pretreatment, gently organic peeling, and adaptive cleaning and repair, silicon wafers can be reused on the production line with minimal loss, significantly reducing production costs and improving material utilization and overall economic efficiency of the production line.
[0052] Based on the same concept of the present invention, as shown in the appendix to the specification. Figure 5 As shown in the embodiment of this application, an electronic device 500 is provided. The electronic device 500 includes: at least one processor 501, at least one network interface 504 or other user interface 503, a memory 505, and at least one communication bus 502. The communication bus 502 is used to enable communication between these components. The electronic device 500 may optionally include a user interface 503, including a display (e.g., touchscreen, LCD, CRT, holographic imaging, or projector), a keyboard, or a clicking device (e.g., mouse, trackball, touchpad, or touchscreen).
[0053] Memory 505 may include read-only memory and random access memory, and provides instructions and data to processor 501. A portion of memory 505 may also include non-volatile random access memory (NVRAM).
[0054] In some implementations, memory 505 stores executable modules or data structures, or subsets thereof, or extended sets thereof: The 5051 operating system contains various system programs used to implement various basic business functions and handle hardware-based tasks. Application module 5052 contains various applications, such as launchers, media players, and browsers, to implement various application functions.
[0055] In this embodiment of the application, by calling the program or instructions stored in the memory 505, the processor 501 is used to execute the steps of an efficient rework method for defective BC battery coating products.
[0056] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, performs steps such as those in an efficient rework method for defective BC battery coatings.
[0057] Specifically, the storage medium can be a general-purpose storage medium, such as a portable disk or hard drive. When the computer program on the storage medium is run, it can selectively and gently peel off the defective film layer, allowing the silicon wafer to be reused on the production line with extremely low loss, thereby improving material utilization.
[0058] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and there may be other division methods in actual implementation. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the mutual coupling or direct coupling or communication connection shown or discussed may be through some communication interface, and the indirect coupling or communication connection of the apparatus or units may be electrical, mechanical, or other forms.
[0059] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0060] In addition, the functional units in the embodiments provided in this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.
[0061] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.
[0062] Finally, it should be noted that the above embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The protection scope of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the scope of the technology disclosed in this application; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application. All should be covered within the protection scope of this application. Therefore, the protection scope of this application should be determined by the protection scope of the claims.
Claims
1. A highly efficient rework method for defective BC battery coatings, characterized in that, The method includes the following steps: Information is entered into the coating process of BC battery production to identify defective silicon wafers. The silicon wafer is inspected using a combination of infrared thermal imager and fiber optic spectrometer to determine the type, location, and severity of defective areas and generate a digital map. Laser irradiation pretreatment is performed on severely defective areas of the silicon wafer in the digital map to weaken the adhesion between the film layer and the silicon substrate; The pre-treated silicon wafer is delaminated using an organic mixed solvent heated to a set temperature in conjunction with a multi-band ultrasonic array; wherein the organic mixed solvent includes a main solvent and a co-solvent, the main solvent being one or more of DMSO, NMP, and DMF, and the co-solvent being an alcohol; The silicon wafers after film removal are sequentially subjected to primary buffer rinsing, adaptive buffer etching, secondary ultrasonic cleaning and repair, dehydration and drying to remove residual silicon oxides on the silicon wafer surface and repair the silicon surface. The dried silicon wafers are sorted into qualified wafers and scrap wafers; the qualified wafers are returned to BC cell production.
2. The efficient rework method for defective BC battery coatings according to claim 1, characterized in that, in, Defective silicon wafers generated during the coating process in BC battery production are transported via baskets; the information entered includes the type of silicon wafer, and different types of silicon wafers correspond to different pretreatment, film removal, and etching parameters.
3. The efficient rework method for defective BC battery coatings according to claim 2, characterized in that, in, First, the silicon wafer is scanned comprehensively using an infrared thermal imager. The temperature difference caused by uneven film thickness or contamination is used to identify macroscopic defect areas by contrasting the images. Then, the micro-area reflectance spectrum of the identified macroscopic defect areas is measured using a fiber optic spectrometer integrated on the infrared thermal imager. By analyzing the spectral curves, the type, location, and severity of the defect areas are determined.
4. The efficient rework method for defective BC battery coating products according to claim 3, characterized in that, in, The location of severely defective areas is determined from the digital map, and a short-pulse laser is used to scan and irradiate the areas according to the laser parameters matched to the defect type, thereby weakening the adhesion between the film and the silicon substrate; the laser energy density in the laser parameters is higher than the silicon nitride film ablation threshold but lower than the silicon damage threshold.
5. The efficient rework method for defective BC battery coating products according to claim 4, characterized in that, The method of removing the film from a pre-treated silicon wafer using an organic mixed solvent heated to a set temperature in conjunction with a multi-band ultrasonic array includes the following steps: The pretreated silicon wafer carrier basket is transferred into the preheated organic solvent dynamic circulation stripping main cavity; the basket rotates within the organic solvent dynamic circulation stripping main cavity. Depending on the type of silicon wafer, the organic mixed solvent in the main cavity is heated to a set temperature and forms a uniform upward laminar flow that washes over the silicon wafer surface. Ultrasonic waves emitted by a multi-band ultrasonic array are used to assist the penetration of the organic mixed solvent. The organic mixed solvent containing film debris is filtered and recycled.
6. The efficient rework method for defective BC battery coatings according to claim 5, characterized in that, The process of sequentially performing primary buffer rinsing, adaptive buffer etching, secondary ultrasonic cleaning and repair, and dehydration and drying on the silicon wafer after film removal includes the following steps: After the film is removed, the silicon wafer is transferred to the first-level buffer rinsing chamber and rinsed with deionized water overflow to remove residual solvent and loose particles. After overflow rinsing, the silicon wafer is transferred into an adaptive buffer etching tank and etched using a fluoride buffer solution to remove residual silicon oxide; the fluoride buffer solution is HF or a buffer solution of NH4F and HF. The etched silicon wafer is transferred into a secondary ultrasonic cleaning chamber, where SC-1 standard cleaning solution is used in conjunction with mega-sonic waves to clean it, remove residual organic matter and repair the silicon surface. The cleaned silicon wafers are transferred into the dehydration and drying chamber, where they are first dehydrated by isopropyl alcohol (IPA) vapor and then dried by nitrogen hot air.
7. The efficient rework method for defective BC battery coatings according to claim 6, characterized in that, in, The dried silicon wafers are subjected to automatic optical inspection and electrical performance evaluation, and are sorted into qualified wafers and scrap wafers according to the test results; silicon wafers with no visible defects on the surface and minority carrier lifetime decay less than a set threshold are classified as qualified wafers.
8. A high-efficiency rework device for defective BC battery coatings, characterized in that, The device includes: The information entry module is used to enter information about defective silicon wafers generated during the coating process in BC battery production. The refined inspection module is used to perform joint inspection of silicon wafers using an infrared thermal imager and a fiber optic spectrometer to determine the type, location, and severity of defective areas and generate a digital map. The laser preprocessing module is used to perform laser irradiation preprocessing on severely defective areas of the silicon wafer in the digital map, in order to weaken the adhesion between the film layer and the silicon substrate. An organic stripping module is used to remove the film from a pre-treated silicon wafer using an organic mixed solvent heated to a set temperature in conjunction with a multi-band ultrasonic array; wherein the organic mixed solvent includes a main solvent and a co-solvent, the main solvent being one or more of DMSO, NMP, and DMF, and the co-solvent being an alcohol; The multi-stage cleaning and repair module is used to sequentially perform first-stage buffer rinsing, adaptive buffer etching, second-stage ultrasonic cleaning and repair, dehydration and drying on the silicon wafer after film removal, in order to remove residual silicon oxide on the silicon wafer surface and repair the silicon surface. The sorting module is used to separate the dried silicon wafers into qualified wafers and scrap wafers; among them, the qualified wafers are returned to BC cell production.
9. An electronic device, characterized in that, include: The device includes a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the electronic device is running, the processor communicates with the memory via the bus. When the machine-readable instructions are executed by the processor, they perform the steps of an efficient rework method for defective BC battery coatings as described in any one of claims 1 to 7.
10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, performs the steps of an efficient rework method for defective BC battery coatings as described in any one of claims 1 to 7.