In this paper, the authors report a high-k samarium oxide (Sm2O3) dielectric grown on the silicon substrate by reactive sputtering. We find that the Sm2O3 gate dielectric after annealing at 700 degrees C exhibits excellent electrical properties such as small equivalent oxide thickness, gate leakage current, frequency dispersion, and stress-induced leakage current. This indicates that annealing at 700 degrees C treatment can prevent the interfacial layer formation, improve the surface roughness, and passivate a large amount of trapped charge at defect sites. (C) 2008 The Electrochemical Society. [DOI: 10.1149/1.2990226] All rights reserved.