Thermally Tunable Vo2-Sio2 Nanocomposite Thin-Film Capacitors

We present a study of co-sputtered VO2-SiO2 nanocomposite dielectric thin-film media possessing continuous temperature tunability of the dielectric constant. The smooth thermal tunability is a result of the insulator-metal transition in the VO2 inclusions dispersed within an insulating matrix. We present a detailed comparison of the dielectric characteristics of this nanocomposite with those of a VO2 control layer and of VO2/SiO2 laminate multilayers of comparable overall thickness. We demonstrated a nanocomposite capacitor that has a thermal capacitance tunability of similar to 60% between 25 degrees C and 100 degrees C at 1 MHz, with low leakage current. Such thermally tunable capacitors could find potential use in applications such as sensing, thermal cloaks, and phase-change energy storage devices. Published by AIP Publishing.