Iron point defect reduction in multicrystalline silicon solar cells

In this work, we propose and demonstrate an annealing procedure designed to improve the performance of iron-contaminated silicon solar cells. Specifically, we put forward the idea that cells contaminated with iron should be annealed at appropriate times and temperatures to allow for the transformation from supersaturated point defects to distributed iron silicide precipitates. We examine the optimal transformation rate for string ribbon multicrystalline silicon and demonstrate that a 30min annealing can improve the efficiency of cells manufactured from low-purity feedstock.