Effects of grown-in stress on the metastable solid solubility limits in Sb implanted Ge_0.1Si_0.9 alloys

Solid phase epitaxy and metastable solubility limits of implanted Sb atoms have been investigated in stressed and stress-relaxed Ge0.1Si 0.9 thin films. For a 5×1015 cm-2 Sb implantation, complete recrystallization is achieved for both samples after a 60 min furnace annealing at 600°C. In the case of stress-relaxed alloy, 91% of the Sb atoms are located at the substitutional sites of the Ge-Si matrix. For the stressed sample, however, only 60% of the Sb atoms occupy the substitutional sites of the matrix. A defect-free regrown layer is observed for the relaxed sample, while twins are formed near the location of the Sb concentration peak in the stressed Ge-Si. The maximum solid solubilities of Sb are estimated to be 1.6×1021 and 8×1020 cm-3 for the relaxed and the stressed Ge0.1Si0.9, respectively.