Similarity and Difference of the Impact of Ion Implantation and Thermal Oxidation on the Lattice Structure of 4H-SiC Surfaces

摘要

Recently, we reported thermal-oxidation-induced lattice distortion locally at the surface region of 4H-SiC caused by the formation of SiO_2/4H-SiC interface, however, the origin of such anomalous distortion has not been clarified yet. In this report, we investigated the impact of O and Ar implantation on the lattice structure of 4H-SiC (0001) surfaces to compare with that of thermal oxidation, directly from the changes of the interspacing of lattice planes perpendicular to the wafer surfaces by in-plane X-ray diffractometry (XRD) analysis. Since the damaged 4H-SiC structure due to O and Ar implantation have also been reported, we may expect a similar effect on the lattice structure on the surface region as that of thermal oxidation if we assume the interstitial atom is the origin of such anomalous distortion of the lattice.