Evaluation of large-scale recycled seed for cast monocrystalline silicon: Defect multiplication mechanisms and feasibility

Abstract The casting method is a low-cost technique to fabricate photovoltaic monocrystalline silicon wafers. The development of cast monocrystalline silicon (CM-Si) materials requires high quality and low cost. To further reduce CM-Si's cost, a large-scale recycled seed has become a focused topic. This work compared new seeds and a large-scale recycled seed in the same growth so that the experimental errors in the growth environment were eliminated. Detailed characterizations on defect distribution and performances have shown that seed recycling will generate extra initial defects. However, it becomes influential for solar cell performance only when defect concentration reaches a certain level. Finally, a related defect propagation mechanism was revealed for manufacturers to optimize industrial growth strategies.