We present a modified valence force field model for the structure and energetics of amorphous silicon suboxides (a-SiOx, 0 ≤ x ≤ 2). The parameters are optimized to fit the results from cluster and periodic density-functional theory (DFT) calculations of various model structures. The potential model well reproduces the DFT energetics of various a-SiOx systems for all O:Si composition ratios. We also examine how the choice of force fields affects the atomic-level description of phase separation in a-SiO x and a-Si/a-SiO2 interfaces using a continuous random network model-based Monte Carlo approach. The results highlight the critical role of the relative rigidity between Si and SiO2 matrices in determination of the structural properties of the Si/SiO2 composite system, such as interface bond topology, degree of phase separation, and abruptness of the interface.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - 6 Jul 2011|