Effect of post-deposition annealing temperature on CeO2 thin film deposited on silicon substrate via RF magnetron sputtering technique

Physical and electrical properties of CeO2 thin film deposited on p-type silicon substrate via the RF magnetron sputtering technique after treating in argon ambient at different annealing temperatures has been investigated and reported. Thickness of the CeO2 thin film was in the range of 30–40 nm measured by an ellipsometer at 5 different points for each sample. Post-deposition annealing was executed in argon ambient for 30 min at four different temperatures (400, 600, 800, and 1000 °C). The physical results demonstrated that the thin film was free of physical defects and root-mean square surface roughness decreased as the annealing temperature increased. X-ray diffraction indicated the occurrence of CeO2 phase with four diffraction planes [(1 1 1), (2 0 0), (2 2 0), and (3 1 1)]. All samples showed negative flat band voltage shift owing to the existence of positive effective oxide charges. Samples annealed at 1000 °C showed the lowest interface trap density, total interface trap density, effective oxide charge, and the highest barrier height. This attributed to the lowest leakage current density (∼1×10−9 A cm−2) and the highest electric breakdown voltage (∼30 V) of the sample when a comparison was made.