Vacancy-type defects produced by 100keV Al+ ion implantation in epitaxial 4H–SiC were studied by positron annihilation spectroscopy. The implantation dose varied from 3 x 1013 to 1015/cm2 and the implantation temperature was 25 to 800C. From the results, it was clear that implantation at high temperatures reduced the number of vacancy-type defects. Furthermore, the defect-cluster size depended upon the implantation temperature; thus suggesting that the vacancies involved were mobile. The positron annihilation experiments also suggested that the defect profile extended deeper into the samples than was expected from the deposited energy distribution and from previous Rutherford back-scattering/channelling measurements.

Vacancy-Type Defects in Al-Implanted 4H–SiC Studied by Positron Annihilation Spectroscopy. J.Slotte, K.Saarinen, A.Y.Kuznetsov, A.Hallén: Physica B, 2001, 308-310, 664-7