Formation mechanism and properties of twinned structures in (111) seeded directionally solidified solar grade silicon

The growth structure of photovoltaic multicrystalline silicon formed by directional solidification presents a high fraction of Σ3 and higher order twins. Previous studies proposed that these complex structures are formed by a succession of 2D nucleation events of Σ3 twins on {111} growth facets at the triple line formed by their intersection with the crucible wall, another crystal, or the surface. In this work, we report the reproducible...