Improved interatomic potential for stressed Si, O mixed systems

Abstract We propose an improved formula of a previous interatomic potential for Si, O mixed systems. The new potential is designed so as to more accurately reproduce the structural property of compressively strained SiO 2 structures, by reducing unnatural steric hindrance caused by a long-range part of a three-body term. As the results of the improvement, (1) compressive stress in SiO 2 film, which was highly overestimated to be 13 GPa by the earlier potential, is reduced to 2.7 GPa, and (2) a spurious peak in Si–O pair correlation function of SiO 2 film disappeared. A limitation of the conventional interatomic potentials and its solution are also discussed.