THE INFLUENCE OF ION MASS AND ENERGY ON THE COMPOSITION OF IBAD OXIDE-FILMS

Dual ion-beam sputtering deposition is a very promising technique for fabricating optical coatings thanks to its very good control of the de position parameters. Unfortunately, the different sputtering yields of the elements composing the films modify the stoichiometry and, conseq uently, may cause an increase of the absorption in the UV range and an undesirable variation of the refractive index. In this work we invest igate the influence of ion-beam assistance on some oxide materials. Si O2, ZrO2, and HfO2. The sputtering yield has been measured by varying the mass (Ar, Xe) and energy (100-1000 eV) of the bombarding ions. The yield measurements were compared with the calculated yields using Sig mund's model. Different screening functions for different characterist ic energy ranges were necessary to fit the experimental results. (C) 1 998 Elsevier Science S.A. All rights reserved.