Nucleation in the multicrystalline Polix silicon ingot

Abstract

An analysis of nucleation from solid nuclei in Polix photovoltaic polycrystalline silicon is reported. The bulk texture is studied by neutron diffraction using a transmission method. The crystallographic orientation is determined for three adjacent samples along the growth axis in the lower central part of the ingot. The size and orientation of all crystallites are obtained in the domains showing different morphologies: a nucleation zone with equiaxed crystallites, an upper domain with columnar structure, and an intermediate part where both types of crystallization are present. The crystallites are counted in terms of their volume in the three parts. The mean grain size increases in the columnar domain, but a pronounced elimination of particular crystalline orientations is not observed as the morphology is changed.