PERC太阳电池退火EL石英舟卡槽印的原因排查与改善措施研究

INVESTIGATION AND IMPROVEMENT MEASURES FOR EL QUARTZ BOAT CARD GROOVE MARKS IN THE ANNEALING PROCESS IN PERC SOLAR CELLS

PERC太阳电池作为目前光伏市场上的主流太阳电池产品,其良品率的稳定及提升受到了太阳电池厂家的高度重视。针对在电致发光(EL)检测时发现PERC太阳电池存在退火EL石英舟卡槽印占比异常的情况,为排查产生原因,对退火工序中使用的石英舟的各个环节进行了分析,并提供了改善措施。分析结果显示:低压石英舟饱和工艺与低压退火工艺过程中的尾气倒灌污染是退火EL石英舟卡槽印太阳电池占比异常的主要原因;通过采用优化变频真空泵设置和加装单向阀的措施,改善了退火工序中尾气倒灌的问题,将生产线退火EL石英舟卡槽印太阳电池月平均占比由0.667%~1.260%降至0.205%,有效提升了PERC太阳电池的良品率。以期为光伏行业改善退火EL石英舟卡槽印问题提供新思路和新方向。

As the mainstream solar cell product in the current PV market,the stability and improvement of the yield of PERC solar cells have been highly valued by solar cell manufacturers.This paper analyzes the various stages of the quartz boat used in the annealing process and provides improvement measures to investigate the abnormal proportion of PERC solar cells with EL quartz boat card groove marks in the annealing process during EL detection.The analysis results show that the main reason for the abnormal proportion of solar cells with EL quartz boat card groove marks in the annealing process is the exhaust backflow pollution during the low-pressure quartz boat saturation process and low-pressure annealing process.By adopting measures such as optimizing the setting of variable frequency vacuum pumps and installing one-way valves,the problem of exhaust backflow in the annealing process has been improved.The monthly average proportion of solar cells with EL quartz boat card groove marks in the annealing process on the production line has been reduced from 0.667%to 1.260%to 0.205%,effectively improving the yield of PERC solar cells.To provide new ideas and directions for the PV industry to improve the EL quartz boat card groove marks in the annealing process.