Effects of helium implantation on hydrogen isotope retention behavior in SiC

To elucidate the interaction between hydrogen isotopes and damaged structures in SiC, deuterium ion (D2+) was implanted into helium ion (He+) implanted SiC. The chemical state of SiC was analyzed by XPS and thermal desorption behaviors of D2 and He were observed by TDS. It was found that D desorption consisted of two stages, namely D bound to Si and that to C. The D was desorbed from both desorption stages for He+ implanted SiC with the low D2+ fluence, although it was preferentially trapped by C for pure SiC. The D retention for He+ implanted SiC was lower than that for pure SiC under the same D2+ fluence. The implanted He mainly forms He blister or remains in the carbon vacancies. The D trapping efficiency was changed by He+ implantation, although the D trapping mechanism was not largely influenced