Heteroepitaxial strains and interface structure of Ge–Si alloy layers on Si (100)

A study is presented of the strains and misfit dislocations in Ge_xSi_{1 −x} strained layers grown epitaxially on (100)Si. Plan-view TEM is used to study dislocation arrays in layers of several thicknesses at two different compositions. The misfit dislocations are demonstrated to be predominantly a/2<011> edge type and the critical thickness is compared with the predictions of various theoretical models.