Molecular‐dynamics study of SiGe epitaxy on a Si substrate

Abstract

Depositions of Ge, SiGe, and Si atoms onto a Si(001) substrate are simulated by means of the classical molecular-dynamics method. The Tersoff potential is employed to calculate the interatomic interactions. In the first kind of simulation, Ge atoms with the velocity corresponding to an energy of 0.2 eV are deposited one by one onto the equilibrated substrate every 200 ps. In the second kind of simulation, Si and Ge atoms are alternately deposited one by one onto the substrate. In the third kind of simulation, Si atoms are deposited. In each simulation, breakdown of epitaxy is observed after several monolayers have been epitaxially deposited. It is concluded that breakdown of heteroepitaxy is delayed due to the increase of the potential energy of the system. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)