Abstract: Methods are disclosed for gas-cluster ion-beam deposition of thin films on silicon wafers rendered free of native oxides by termination of the surface bonds and subsequent reactive deposition. Hydrogen termination of the surface of silicon renders it inert to reoxidation from oxygen-containing environmental gasses, even those found as residue in vacuum systems, such as those used to deposit films. Nitrogen termination improves the interface with overlying metal-oxide thin films. The film is formed in intimate contact with the silicon crystal surface forming a nearly ideal interface.