Stillinger-Weber potentials for III–V compound semiconductors and their application to the critical thickness calculation for InAs/GaAs

Parameters in the Stillinger-Weber interatomic potentials are obtained for III–V compounds from the cohesive energy, the lattice constant, and the elastic properties. The obtained potentials coincide with the Keating potentials for small distortion (<1%) but are more accurate for larger distortion. Using the SW potentials, the critical thickness of misfit dislocation nucleation is calculated for InAs/(001)GaAs. The critical thickness is 5 ML for a 60° dislocation and 2 ML for an edge dislocation. These thicknesses are smaller than those calculated using the Keating potentials. Results obtained by the classical elastic theory do not agree with the present results.