Cross-sectional investigation of radiation damage of 2 MeV proton-irradiated silicon carbide

Cross-sectional investigation is an important method to study ion irradiation effects in the depth direction. In this study, 2 MeV H+ was implanted in 6H-SiC single crystals to investigate the effects of light ion irradiation on SiC. Raman spectroscopy and scanning electronic microscopy (SEM) were carried out on cross-sectional samples to reveal the in-depth damage states and dopant behavior. The most damaged region is a little shallower than that predicted by the SRIM procedure, owing to the uncertainty in SRIM simulations. Layered structures representing zones of varying damage after 2 MeV H ion irradiation are clearly observed. Two bands are observed in SEM images, of which on band corresponds to the damage peak, while the other band at the end of the H ion-affected area is probably a result of H diffusion propelled by a hydrogen-rich layer during irradiation. A charge accumulation effect related with conductivity on the sample surfaces during SEM tests is observed in the H-implanted area. A model is proposed to explain these phenomena.