The 3C -6H polytypic transition in SiC as revealed by diffuse X-ray scattering

International audienceThe 3C-6H polytypic transition in SiC single crystals is studied by means of diffuse X-ray scattering. Based on numerical simulations of the diffuse scattering intensity distribution we unambiguously prove that the 3C-6H transition in SiC occurs through the glide of partial dislocations and not by the "layer displacement" mechanism (i.e. local diffusional rearrangement of the Si and C atoms). The technique is extremely sensitive and can be used as a non-destructive mean to obtain statistically relevant values of the transition level down to ~0.05%