The influence of electrode contact on the anodization of Pt/sol–gel derived SrTiO3 thin film/Al capacitor

Abstract

When the valve metal is used as anode material, the dielectric properties of sol–gel-derived thin film are greatly enhanced. That is because anodized self-healing occurs at the interface of the anode and the thin film. An oxide insulating layer with a good dielectric property is generated. Anodization heals the defects and the breakdown spots of thin film. Other than anodized self-healing, electrode contact is also an important factor, affecting the dielectric characteristics of the thin film capacitor, which cannot be ignored, especially when both factors exist in one film device. In this study, the sol–gel-derived strontium titanate thin film is used as dielectric material in the film capacitor, and platinum and aluminum as electrode materials. We find that the Schottky barrier at the interface of platinum and strontium titanate greatly reduces the leakage current. However the interface barrier restricts the anodizing of aluminum electrode and the further enhancement of the dielectric strength of the thin film capacitor.