In Situ Preparation of VO2 Films with Controlled Ionized Flux Density in HiPIMS and Their Regulation of Thermal Radiance

Abstract

Vanadium dioxide is a well-known phase-change material on account of its unique changes of optical property, which has seen a great increase in its implementation for the regulation of thermal radiance. However, the fabrication of VO2 needs strict conditions for its narrow sliver in the phase diagram. In this paper, in situ preparation of VO2 films by high-power impulse magnetron sputtering is proposed, in which ionized flux density is used to direct the crystal growth. Besides, the surface structure and thermochromic behaviors of the deposited films are studied in detail. Furthermore, simulations are carried out for the sake of optimizing the thickness of VO2 films with the largest emissivity modulation ability, and the experimental result reveals that their tuning range reaches up to 0.32. It is believed that our work will find wide applications not only in fundamental material science but also in thermal radiance regulation.