We report the creation of two novel complementary metal oxide semiconductor CMOS -compatible platforms: strained-silicon onsilicon SSOS and strained-silicon on silicon-germanium on silicon SGOS . SSOS substrate has an epitaxially defined, strained-silicon layer directly on silicon wafer without an intermediate SiGe or oxide layer. SSOS is a homochemical heterojunction, i.e.,a heterojunction defined by strain state only and not by an accompanying compositional change. SGOS has an epitaxially definedSiGe layer between the strained-silicon channel and the Si substrate, which may prove necessary to prevent excessive off-stateleakage in metal oxide semiconductor MOS devices due to overlap of source-drain contacts and the interfacial misfit array© 2005 The Electrochemical Society. DOI: 10.1149/1.2139951 All rights reserved.Manuscript submitted May 14, 2005; revised manuscript received September 23, 2005.Available electronically December 30, 2005.