Stress, strain and elastic energy at nanometric Ge dots on Si(001)

We perform molecular dynamics simulations to obtain the stress and strain distributions for Ge pyramids with {105} facets on Si(001). We show that the strain induced in the substrate is large and increasing with the pyramid size: up to 0.7% for the 22 nm in base, and corresponds to substrate bending below the pyramid, (C) 2002 Elsevier Science B.V. All rights reserved.

Stress, strain and elastic energy at nanometric Ge dots on Si(0 0 1) were obtained using molecular dynamics simulations. The model was composed by a 43 nm wide and 8.1 nm thick silicon substrate, covered by a Ge wetting layer. The configuration at equilibrium was achieved by a simulated annealing at 600 K and quenching at 0 K. Results indicated that stress induced in the substrate by Ge pyramids played an important role in the energetics of the dot and in possible Si band gap modulations.