Epitaxial growth of ultra-thin CeO2 layers on Si(100) substrates is studied using reactive DC magnetron sputtering enhanced with an inductively coupled RF plasma. Orientation-selective epitaxial growth of CeO2(100) and CeO2(110) is realized by controlling substrate bias and the growth rate, adopting a two-step growth method: ultrathin metallic Ce layer deposition at room temperature followed by silicidation process at several hundreds degree C, and subsequent reactive sputtering in an Ar/O-2 mixture environment using a Ce metal target at elevated temperature. It is important that epitaxial growth of both directions is realized on practical H-terminated surfaces obtained by the usual wet process. Details on the growth parameter maps for the orientation selection are reported in terms of substrate bias, plasma power and the growth rate. (C) 2004 Elsevier B.V. All rights reserved.