Formation of defect structure on Ge surface by ion irradiation at controlled substrate temperature

Abstract

Ge (001) surface was irradiated by 60 keV Sn ions to a fluence of 8 × 1018 ions/m2 at a controlled substrate temperature, and the formation of defects was investigated. A damaged layer of about 50 nm thickness was formed on the surface at 150K. In the case of irradiation at room temperature, a damaged layer was also created, but voids of about 15 nm diameter were created near the top surface. This result is explained by the high mobility of vacancies during irradiation at room temperature, and it is confirmed that the void formation process is dominated by the migration of induced point detects. © 2011 The Japan Institute of Metals.