EVOLUTION OF DIFFUSE-SCATTERING DURING 2H TO 6H DIRECT TRANSFORMATIONIN SIC

We discuss the limitations of the earlier models in explaining the evo lution of diffuse scattering during the 2H to 6H direct transformation in single crystals of SiC above 2000 degrees C. Monte Carlo technique is employed to predict the diffuse scattering along c using a nuclea tion and growth model. The results obtained by simulation are compared with those obtained analytically, assuming sequential insertion of st acking faults. The predicted diffraction effects are found to be in ag reement with those observed experimentally. It is shown that the short range and long range correlations are in conflict for the arrest stat e of the 2H to 6H 'direct' transformation.