IN-SITU OBSERVATION OF META-INDUCED CRYSTALLIZATION OF AMORPHOUS SI_(0.8)GE_(0.2) THIN FILMS

摘要

Polycrystalline SiGe (Poly-SiGe) thin films are of interest for the fabrication of thin film transistors in optoelectronic devices. The crystallization of a-Si_(0.8)Ge_(0.2) thin films induced by Ni was investigated by in-situ transmission electron microscopy. For the Ni-induced crystallization, NiSi_2 precipitates were first formed then migrated along a straight line in a-Si_(0.8)Ge_(0.2). The crystallization of a-Si_(0.8)Ge_(0.2) was induced along the path. The reversal of the growth direction of the needle-like crystallites was also observed. It appeared that the NiSi_2 precipitates migrated along the interface of the crystallized and amorphous regions. The results are different from the branching needle-like structure for Ni-induced crystallization of a-Si.