Impact of Optimization for Mass Production PERC Solar Cell with Efficiency above 23%

In this work, we demonstrate that p-type PERC solar cells can also improve mass production efficiency and productivity based on the current PERC structure process. By changing the POCl3 parameters in the diffusion process, the productivity of the diffusion process can be effectively increased by 7.5% and the efficiency is slightly improved. For the front anti-reflective layer process, it could be found that the reducing the n value of the anti-reflective multi-layer would increase the light absorption of the solar cells, which can effectively increase the photocurrent of about 25~30mA. In the process of rear side passivation layer, the temperature of CVD process optimization can effectively enhance the passivation effect, and the photocurrent and open circuit voltage are both improved. By applying above three process-optimized parameters to the production line process, it can be found that the conversion efficiency can be increased by 0.15% to 0.2%, and the productivity can be improved as well. Finally, we took the same efficiency level of experiment cells and the reference cells for module testing. It was found that the cell to module (CTM) degradation of the Optimized group was lower than the reference group, which means the quality of solar cells to modules could be effectively improved. The related quality test of all solar cells also complied with IEC specifications.