The diffusion behaviours of vanadium implanted P-and n-type 4H-SiC are investigated by using the secondary ion mass spectrometry(SIMS).Significant redistribution,especially out-diffusion of vanadium towards the sample surfaceis not observed after 1650°C annealing for both P-and n-type samples.Atomic force microscopy(AFM)is applied to the characterization of surface morphology,indicating the formation of continuous long furrows running in one direction across the wafer surface after 1650°C annealing.The surface roughness results from the evaporation and re-deposition of Si species on the surface during annealing.The chemical compositions of sample surface are investigated using x-ray photoelectron spectroscopy(XPS).The results of C 1s and Si 2p core-level spectra are presented in detail to demonstrate the evaporation of Si from the wafer and the deposition of SiO2 on the sample surface during annealing.