We report on the epitaxial deposition of Sm2O3, Dy2O3, and Ho2O3 films on Si (111) substrates as progress towards developing a predictive model for gate oxide selection. To date, films,have been characterized by reflection high-energy electron diffraction, x-ray diffraction (XRD), and x-ray photoemission spectroscopy (XPS). In the case of Sm2O3, difficulty was encountered in achieving the growth of phase pure films; growth of the desired bixbyite oxide phase was accompanied by significant amounts of monoclinic oxide as detected by XRD. Dy2O3 and Ho2O3 films can be produced free of unwanted phases when deposited using a background pressure of 1 x 10(-6) torr O-2/O-3 and a substrate temperature between 425 and 550 degrees C. Dy2O3 films with an x-ray peak width of 0.6 degrees in to were obtained. XPS studies of the Dy2O3/Si interface are in progress, and verify the phase purity of the films. (c) 2006 American Vacuum Society.