Comparison of cavities and extended defects formed in helium-implanted 6H-SiC at room temperature and 750 ℃

The formation of cavities in silicon carbide is vitally useful to “smart-cut” and metal gettering in semiconductor industry. In this study, cavities and extended defects formed in helium (He) ions implanted 6H-SiC at room temperature (RT) and 750 ℃ followed by annealing at 1500 ℃ are investigated by a combination of transmission electron microscopy and high-resolution electron microscopy. The observed cavities and extended defects are related to the implantation temperature. Heterogeneously distributed cavities and extended defects are observed in the helium-implanted 6H-SiC at RT, while homogeneously distributed cavities and extended defects are formed after He-implanted 6H-SiC at 750 ℃. The possible reasons are discussed.