Dopant diffusion and surface morphology of vanadium implanted 4H-silicon carbide

The diffusion behaviours of vanadium implanted p- andn-type 4H-SiC are investigated by using the secondaryion mass spectrometry (SIMS).Significant redistribution, especially out-diffusion of vanadium towards thesample surface is not observed after 1650℃ annealing for both p-and n-type samples. Atomic force microscopy (AFM) is applied to thecharacterization ofsurface morphology, indicating the formation of continuous long furrowsrunning in one direction across the wafer surface after 1650℃ annealing. The surface roughness results from theevaporation and re-deposition ofSi species on the surface during annealing. The chemical compositions ofsample surface are investigated using x-ray photoelectron spectroscopy (XPS).The results of C 1s and Si 2p core-level spectra are presented in detail todemonstrate the evaporation of Si from the wafer and the deposition of SiO₂on the sample surface during annealing.