The {111} Σ3 and {112} Σ3 twin boundaries and their junctions in phosphor-doped cast polycrystalline Si were investigated by EELS using HREM to study the local electrical properties and impurity effects at these boundaries and junctions. FWHMs of the Si plasmon-loss peaks were wider at the grain boundary junctions and {112} Σ3 twin boundary as compared with other area partly because of the overlapped effect of plasmon loss of SiO2 and C. In the inner-shell edge part of EELS spectrum, the grain boundary junction having distorted structure exhibited slightly strong intensity at around 110eV, suggesting the formation of nano-size SiO2, even though the presence of the SiO2 could not be observed by HREM. The effects of C K-edge could be recognized in the EELS spectra acquired at {111} Σ3 and {112} Σ3 boundaries and their junctions, suggesting the grain boundary segregation of C atoms.

EELS Analysis of {111} Σ3 and {112} Σ3 Twin Boundaries and their Junctions in Phosphor-Doped Cast Polycrystalline Silicon. I.Kuchiwaki, K.Sugio, O.Yanagisawa, H.Fukushima: Solar Energy Materials and Solar Cells, 2008, 92[1], 71-5