H + implantation-enhanced stress relaxation in c-Si 1−xGe x on SiO 2 during oxidation-induced Ge condensation process

Abstract

Enhancement effects of H + implantation on stress relaxation of c-Si 1− x Ge x layers on SiO 2 during oxidation-induced Ge condensation process have been investigated. Stress relaxation of c-Si 1− x Ge x layers during oxidation (1100 °C) was significantly improved by high-dose (>10 15 cm −2) H + implantation. However, oxidation was also enhanced by implantation. Enhanced oxidation was completely suppressed by the two-step annealing (1st: 500 °C for 30 min, 2nd: 850 °C for 60 min) before oxidation. The enhanced stress relaxation was tentatively assigned to enhanced gliding of c-Si 1− x Ge x layers on SiO 2. This newly developed combination method of H + implantation, two-step annealing, and oxidation-induced Ge condensation will be a powerful tool to fabricate highly relaxed c-Si 1− x Ge x buffer layers for growing strained Si layers.