Bending of nanoscale thin Si film induced by growth of Ge islands: hut vs. dome

We perform atomistic simulations to compute bending of freestanding nanoscale thin Si film induced by strained Ge islands. We show that a larger Ge dome island can induce smaller bending than a smaller hut island and explain the surprising experimental observation for growth of Ge islands on patterned silicon-on-insulator substrate (SOI) with Si template layer thinned down to nanometer scale. This counterintuitive bending behavior is caused by strain sharing between the film and the ultra thin substrate.