Composition and stress of SiGe nanostructures on curved substrates

Abstract

Recent experimental studies of Ge nanoislands on silicon-on-insulator (SOI) substrates have provided a defect-free strain relaxation mechanism through the bending of the substrate. Here, using atomistic Monte Carlo simulations and analytical modeling, we couple this relaxation mechanism with interdiffusion and alloying and observe composition profiles that are completely different from those observed in flat nanoislands. Moreover, for comparable SOI and island thicknesses, intermixing can be greatly reduced and Ge content in the islands is highly preserved.