Growth, characterization and interfacial reaction of magnetron sputtered Pt/CeO2 thin films on Si and Si3N4 substrates

Abstract

Growth of magnetron sputtered Pt/CeO2 thin films on Si and Si3N4 were characterized by X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) and X‐ray photoelectron spectroscopy (XPS). Interaction of Pt/CeO2 films with Si on Si and Si3N4 substrates was extensively investigated by XPS. XRD studies show that films are oriented preferentially to (200) direction of CeO2. XPS results show that Pt is mainly present in +2 oxidation state in Pt/CeO2/Si film, whereas Pt4+ predominates in Pt/CeO2/Si3N4 film. Concentration of Pt4+ species is more than four times on Si3N4 substrate as compared with that on Si. Ce is present as both +4 and +3 oxidation states in Pt/CeO2 films deposited on Si and Si3N4 substrates, but concentration of Ce3+ species is more in Pt/CeO2/Si film. Interfacial reaction between CeO2 and Si substrate is controlled in the presence of Pt. Pt/Ce concentration ratio decreases in Pt/CeO2/Si3N4 film upon successive sputtering, whereas this ratio decreases initially and then increases in Pt/CeO2/Si film. Copyright © 2015 John Wiley & Sons, Ltd.