Ab-initio calculations and structural studies of (SiTe)2(Sb2Te3)n (n: 1, 2, 4 and 6) phase-change superlattice films

Abstract

(SiTe)2(Sb2Te3)n phase-change superlattices were investigated theoretically and experimentally. Ab-initio first principle simulations predicted that the (SiTe)2(Sb2Te3)n structures are stable and possess a Dirac semimetal-like band structure. Calculation of the Z2 invariant indicated that the structure was topologically nontrivial. (SiTe)2(Sb2Te3)n superlattice structures derived from first-principles were successfully fabricated on a Si substrate by RF-magnetron sputtering. XRD and TEM indicated that the superlattice films were highly oriented with the 00X planes of Sb2Te3 and the superlattice normal to the substrate surface. The (SiTe)2(Sb2Te3)n superlattice is suggested as new material system for interfacial phase-change memory applications. © 2014 The Authors. Phys. Status Solidi RRL is published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim • This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.