Role of Impurities in Silicon Solidifica

All silicon (Si) ingot fabrication processes share challenges to control grain structure, defect and impurity contamination during the solidification step to improve the material properties. The final grain structure and inherent structural defects issued from the solidification step are responsible for the photovoltaic (PV) properties for a large part, all the more as they are often associated with impurity distribution. This study explores how impurities affect the solidification of silicon and its electrical properties using complementary in situ and ex situ methods. We analyze the implications of various defect types and impurity concentrations on the quality of silicon ingots, particularly focusing on metallic impurities such as copper. Experimental results demonstrate that the concentration of impurities significantly influences the development of structural defects, directly impacting the photovoltaic efficiency of the material. The insights gained from this research are critical for optimizing silicon solidification processes and enhancing material performance in photovoltaic applications.