Interaction between hydrogen isotopes and damaged structures produced by He+ implantation in SiC

To understand the interaction mechanism between implanted hydrogen isotopes and damaged structures in SiC, helium (He+) ions were pre-implanted into SiC and thereafter implanted by D2+ ions. The chemical behavior of Si and C, and deuterium retention were evaluated by X-ray photoelectron spectroscopy (XPS) and thermal desorption spectroscopy (TDS). It was found that the decreasing rate of retention of D bound to Si was higher than that bound to C by He+ pre-implantation, indicating that He+ mainly interacts with the D trapping site with Si, namely carbon vacancies, and the displacement of C atoms would occur. Some He remained in the carbon vacancies and desorbed by heating. Some displaced C would migrate to the surface and aggregate on the surface by heating above 1300 K, although most of Si–C bond was recovered.