Electro-thermal control of aluminum-doped zinc oxide/vanadium dioxide multilayered thin films for smart-device applications.

ABSTRACT

We demonstrate the electro-thermal control of aluminum-doped zinc oxide (AlZnO) /vanadium dioxide (VO2) multilayered thin films, where the application of a small electric field enables precise control of the applied heat to the VO2 thin film to induce its semiconductor-metal transition (SMT). The transparent conducting oxide nature of the top AlZnO film can be tuned to facilitate the fine control of the SMT of the VO2 thin film and its associated properties. In addition, the AlZnO film provides a capping layer to the VO2 thin film, which inhibits oxidation to a more energetically favorable and stable V2O5 phase. It also decreases the SMT of the VO2 thin film by approximately 5-10 °C because of an additional stress induced on the VO2 thin film and/or an alteration of the oxygen vacancy concentration in the VO2 thin film. These results have significant impacts on technological applications for both passive and active devices by exploiting this near-room-temperature SMT.