In this paper, epitaxial gadolinium oxide (Gd2O3) is reviewed as a potential high-K gate dielectric, both "as deposited" by molecular beam epitaxy as well as after integration into complementary metal oxide semiconductor (CMOS) processes. The material shows promising intrinsic properties, meeting critical ITRS targets for leakage current densities even at subnanometer equivalent oxide thicknesses. These epitaxial oxides can be integrated into a CMOS platform by a "gentle" replacement gate process. While high temperature processing potentially degrades the material, a route toward thermally stable epitaxial Gd2O3 gate dielectrics is explored by carefully controlling the annealing conditions. (C) 2009 American Vacuum Society. [DOI: 10.1116/1.3054350]