Million-atom molecular dynamics simulation of flat InAs overlayers with self-limiting thickness on GaAs square nanomesas

Large-scale molecular dynamics simulations are performed to investigate the mechanical stresses in InAs/GaAs nanomesas with {101}-type sidewalls. The in-plane lattice constant of InAs layers parallel to the InAs/GaAs(001) interface starts to exceed the InAs bulk value at the twelfth monolayer (ML) and the hydrostatic stresses in InAs layers become tensile above ∼12 ML. As a result, it is not favorable to have InAs overlayers thicker than 12 ML. This may explain the experimental findings of the growth of flat InAs overlayers with self-limiting thickness of ∼11 ML on GaAs nanomesas. © 2001 American Institute of Physics.