Revealing the effect of phosphorus diffusion gettering on industrial silicon heterojunction solar cell

Here we have conducted a comprehensive experimental and theoretical investigation into the impact of the phosphorus diffusion gettering (PDG) process on n-type industrial silicon heterojunction (SHJ) solar cells. Our findings indicate that phosphorus penetrates deeply into the silicon substrate as circular channels. While PDG effectively eliminates Fe from silicon wafers, it also introduces impurities like O, P, and Cu, which are not entirely eradicated during subsequent cleaning and texturing processes. Optimizing the gas flow to 1000 sccm achieved a balance between carrier lifetime and saturated dark current density in SHJ solar cells, resulting in a 0.21 % increase in average efficiency to 25.14 %. Simulated analyses revealed that variations in energy loss due to different gas flows were primarily attributed to bulk recombination and series resistance. Our work provides valuable insights for the application and improvement of the PDG process in industrial SHJ solar cells.