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

(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 00 X 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 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]