Controllable phase transition temperature by regulating interfacial strain of epitaxial VO2 films

Abstract

Modulation of the vanadium oxide epitaxial film metal insulator transition process through interfacial strain is a novel approach for controlling the properties of epitaxial vanadium oxide films, improving its scope for device applications. In this work, vanadium oxide films of various thickness were prepared and the effects of strains on the transition temperature were investigated. The vanadium oxide films exhibited compressive or tensile interfacial strain along their c-axis, the transition temperature varied in a range of 310–370 K owing to the effects of the interfacial strains. The tensile strain along the c-axis is correlated with an increase in transition temperature; however, the compressive strain along the c-axis leads to a decrease in transition temperature. The results show that the metal insulator transition process of vanadium oxide thin films can be regulated by interfacial strain. This work shows the feasibility of engineering the phase transition of epitaxial vanadium oxide films or the related devices through strain manipulating, which may be of great importance in practical applications.