Hybrid Electrothermal Model for Insulator-to- Metal Transition in VO2 Thin Films

Comprehensive model for the insulator to metal phase transition in vanadium dioxide thin film in the presence of external electrical stimulus is proposed. This model divides the film layer into several segments and solves the Joule heating equations due to current flow and heat exchange with the environment and Poole–Frankel equation to obtain carrier concentration in response to the applied voltage, and transition is checked for each cell separately. The model follows the experimental results and exhibits both switching and hysteresis effect in planar structures and
${S}$
-shaped current–voltage characteristics in sandwich metal–insulator–metal structure based on the vanadium dioxide thin film. This model shows that by reducing the vanadium dioxide layer thickness, the electric field-assisted transition plays the dominant role in the transition, and therefore, it is a promising tool for the design and analysis of vanadium dioxide structures with various electrode distances.