On deformation and fracture of semiconductors

Recent experiments on deformation of semiconductors show an abrupt change in the variation of the critical resolved shear stress with temperature. This implies a change in the deformation mechanism at a critical temperature T-c. In the cases examined so far in our laboratory and elsewhere, this critical temperature appears to coincide approximately with the brittle-ductile transition temperature of the material. In this paper, we describe TEM investigations that have been performed on the wide bandgap semiconductor, SiC, deformed at temperatures below and above T-c in order to understand the change of mechanism. Based on these deformation and TEM experiments, suggestions are made as to the different mechanisms operating at low and high temperatures in semiconductors, and a possible relation between T-c and the brittle-ductile transition temperature in these materials.