Ion beam induced excess vacancies in Si and SiGe and related Cu gettering

Implantation-induced excess vacancies and the related Cu gettering was studied in Si and in the solid solution Si0.93Ge0.07. The excess vacancy and interstitial generation during normal and inclined ion implantation can be simulated by a simple binary collision process. The excess defects are shown to control the Cu gettering observed in Si after rapid thermal annealing at a temperature of 900oC. The vacancy concentration in the SiGe layer is higher than in Si. An additional vacancy concentration of about 3.15´1018cm-3 was determined in the SiGe layer beside the implantation-generated excess vacancies. These vacancies are presumably incorporated by the SiGe layer deposition on Si substrate. Vacancies agglomerate and form cavities during annealing. The cavities in SiGe were found to be significantly larger than in Si.