Influence of Yttrium Addition on the High Capacitance of ZrO2-SiO2 Nanocomposite Anodic Oxide Films

Abstract

The sputter-deposited Zr-Si-Y film was anodized to form a high capacitance composite anodic film, comprising a tetragonal ZrO2 nanocrystalline phase and a silicon-enriched amorphous phase. It was found that the nanocomposite anodic film, as well as the yttrium-free ZrO2-SiO2 anodic film, showed markedly increased capacitance compared with the anodic film ZrO2 film on zirconium. The incorporation of yttrium species to the anodic ZrO2-SiO2 film did not change the thickness and permittivity of the anodic oxide film, although a thicker anodic film was formed on zirconium by the incorporation of yttrium, which may introduce oxygen vacancies in the crystalline ZrO2. The findings suggest that in the composite ZrO2-SiO2 anodic films the film thickness is mainly controlled by the silicon-enriched amorphous phase.