Abstract
CeO2 thin films were prepared on Si(100) and Si(111) substrates from cerium acetate monohydrate via sol-gel process. The thin films were crystallized at approximately 700°C and had polycrystalline microstructure. Scanning electron microscopy (SEM) observation showed that those films consisted of small grains of 60-70nm in diameter and had even surfaces. SrTiO3 films with a platinum top electrode were formed on Pt/Si and Pt/CeO2/Si substrates. Current voltage (I-V) characteristics of the SrTiO3 films were measured on Pt/SrTiO3/Pt/Si and Pt/SrTiO3/Pt/CeO2/Si structures. The leakage current density for the former sample was approximately 6.6×10-6A/cm2 under the applied electric field of 9.4×104V/cm. An increase in the applied electric field above 9.4×104V/cm resulted in a marked increase in the leakage current. The leakage current for the latter sample was 4.1×10-6A/cm2 under 2.5×105V/cm. The I-V characteristics of the SrTiO3 films were improved by the use of the CeO2 film as an intermediate layer.
