The effect of biaxial stress on the solid phase epitaxial crystallization of GexSi((1-x)) films

Two fully-strained, Si rich, GexSi(1-x) alloys deposited on (100) Si by CVD were amorphized including part of the substrate and recrystallized at different temperatures in the range 500–620°C. The amorphous-crystal interfaces remain flat during crystallization, and the films grow coherently with the substrate producing crystalline, defect-free, strained heteroepitaxial layers. The kinetics of the process, compared with literature data of the corresponding relaxed alloys, are affected by the presence of the in-plane stress at the interface, resulting in a decrease of the velocity, in quantitative agreement with the predictions of the activation strain model in the case of biaxial stress.