Orientational phase diagram of the epitaxially strained Si(001): Evidence of a singular (105) face

By exploiting the misfit strain of Ge on Si epitaxy, we examine the significant changes induced by surface stress in the polar structural phase diagram of Si(001) surfaces. Under compressive strain, the atomic and mesoscale structures of the vicinal Si(001) surfaces are converted into a new singular (105) face which does not exist on the strain-free equilibrium shape of Si and Ge. The observed structural modifications of substrates have far-reaching implications for the Stranski-Krastanov evolutionary path of three-dimensional islanding. © 2012 American Physical Society