Characteristics of Y2O3 films on Si(111) grown by oxygen-ion beam-assisteddeposition

We investigated the dependence of the crystallinity, strain, and morphologi cal characteristics of epitaxial Y2O3 films grown on Si(lll) by ion beam-as sisted deposition. Various characterization tools, such as reflection high- energy electron diffraction, X-ray diffraction, high-resolution transmissio n electron and atomic force microscopy, were used to reveal the physical pr operties which depend on the assisted energy of the oxygen-ion beam. When t he assisted energy of the oxygen-ion beam was applied to grow films, the gr owth temperature for epitaxy was lowered. The crystallinity was improved an d the film was compressed as the assisted energy increased up to 45 eV, whi le the improvement of crystallinity and the strain increment was suppressed as the assisted energy increased further. Moreover, the morphological shap e shows that island growth is induced when ion energy is supplied. That is, when the ion energy is increased, islands are expanded and the surfaces ar e flattened. The surface morphology yields information on film characterist ics. such as crystallinity and strain, both of which depend on the assisted energy of the oxygen ion. (C) 2001 Elsevier Science B.V. All rights reserv ed.