Solid phase epitaxy of stressed and stress‐relaxed Ge‐Si alloys

Solid phase epitaxy of 3500‐A‐thick GexSi1−x (0.04≤x≤0.12) films on (100) Si substrates has been investigated. The thickness of regrown layers increased linearly with annealing time in the temperature range of 475–575 °C. The regrowth rates of stressed alloys were less than those of pure Si, while stress‐relaxed alloys have larger rates than Si. The difference in regrowth rates was explained by the activation‐strain tensor model (Aziz, Sabin, and Lu, to be published in Phys. Rev. B). The first element of the activation‐strain tensor obtained in this experiment was in excellent agreement with that deduced by Aziz et al. For low Ge concentrations (x<0.08), the recrystallized region was of good crystalline quality. However, threading dislocations were observed in a stressed Ge0.1Si0.9 alloy after complete recrystallization. During the regrowth at 550 °C, the Ge‐Si alloy first regrew coherently up to 300 A, above which threading dislocations started to nucleate. On the other hand, no dislocations were detecte...