Study of solar silicon multicrystals by SEM and EPMA methods

Abstract

Multisilicon crystals grown from refined metallurgical silicon are studied by scanning electron microscopy (SEM) and electron probe microanalysis (EPMA). The varieties of intergranular boundaries are revealed. Impurities are found to be contained in inclusions in multisilicon. The intergranular boundaries contain no impurities, and they do not concentrate the elements present in multisilicon. It is proved experimentally that, in the homogeneous areas of the crystal the lifetime of minor charge carriers is maximum, whereas its minimum value corresponds to the areas with numerous intergranular boundaries.