A systematic investigation was made of the microstructures in particular zones of Si multicrystals which exhibited a strong local variation in minority carrier diffusion length. It was found that 3 typical regions, having distinct microstructures, corresponded to the microscopic origins of the local minority carrier diffusion length difference. A region with a perfect twin structure (Σ3 boundaries) had a high minority carrier diffusion length, while regions with either high-angle grain boundaries (Σ9 or Σ27) or sub-grain boundaries (high-density dislocations) exhibited lower minority carrier diffusion.

Microstructures of Si Multicrystals and their Impact on Minority Carrier Diffusion Length. H.Y.Wang, N.Usami, K.Fujiwara, K.Kutsukake, K.Nakajima: Acta Materialia, 2009, 57[11], 3268-76