Kinetics of the 3C-6H polytypic transition in 3C-SiC single crystals: A diffuse X-ray scattering study

International audienceIn this work, the kinetics of the 3C-6H polytypic transition in 3C-SiC single crystals are studied in details by means of diffuse x-ray scattering (DXS) coupled with numerical simulations and transmission electron microscopy and optical birefringence microscopy. Upon high-temperature annealing, spatially correlated stacking faults (SFs), lying in the {111} planes, are generated within the crystal and tend to form bands of partially transformed SiC. It is shown that the numerical simulation of the DXS curves allows to unambiguously deduce the transformation level within these bands, as well as the volume fraction corresponding to these bands. Increasing annealing time results (1) in the growth of the partially transformed regions by the glide of the partial dislocations bounding the SFs and (2) in the generation of new SFs within the crystal by means of a doublecross slip motion. The kinetics of each of these mechanisms are presented and discussed with respect to the annealing temperature, the initial SF density and crystalline quality