An attempt was made to grow Si bicrystals having a controlled grain boundary configuration by using a pair of single-crystal seeds purposely designed to have a specific character. The float-zone technique, under ultra-high vacuum, was used to grow bicrystals. The growth rate was found to be important in controlling the grain-boundary configuration. The bicrystals thus grown were useful for fundamental studies of the role played by grain boundaries which might control the overall properties of multi-crystals. As an example, a series of bicrystals were grown using seed crystals having a specified Σ3 misorientation and processed into solar cells. The short-circuit current density was found to be strongly affected by the misorientation of the seed.

Floating Zone Growth of Si Bicrystals Using Seed Crystals with Artificially Designed Grain Boundary Configuration. N.Usami, M.Kitamura, T.Sugawara, K.Kutsukake, K.Ohdaira, Y.Nose, K.Fujiwara, T.Shishido, K.Nakajima: Japanese Journal of Applied Physics, 2005, 44[24], L778-80