Wurtzite SiC Formation in Plastic Deformed 3C and 6H

Abstract

Single side clamped 3C and 6H single crystal silicon carbide beams were elastic deformed using a special designed deformation stage in an electron microscope and subjected to high temperatures. The structural transitions occurring during the plastic relaxation process were recorded in situ in the electron microscope using reflection high energy electron diffraction in {110} azimuthal direction. For both polytypes, a polytype phase transition into the wurtzite silicon carbide polytype was observed independent on the surface polarity. The critical initial elastic deformation of the polytype phase transition into the wurtzite phase for the cubic silicon carbide polytype is larger compared to the 6H-SiC. This is due to the higher partial dislocation densities needed to transform the cubic modification into the wurtzite phase.