Study of the misfit dislocations in semiconductor heterostructures by density functional TB molecular dynamics and path probability methods

The atomic and electronic structures of semiconductor heterostructures are studied using the density-functional tight-binding molecular dynamics simulations. Atomic structures of misfit dislocations both edge type 1/2 <110> (001) and 60degrees dislocations in the semiconductor heterostructures, like Ge/Si(001), InAs/GaAs and InP/GaAs(001) systems are studied by using order of N [O(N)] calculational method. The path probability method in the statistical physics is used to study the influence of the interface disorder on the atomistic properties of the semiconductor heterostructures. It is shown that the compositional intermixing influences quite significantly on the electronic and thermodynamic properties of semiconductor heterostructures, especially on the critical layer thickness h(c) for the generation of misfit dislocations. (C) 2003 Published by Elsevier Science Ltd.