Integration of VO2 Thin Films on Si(100) for Thermal Switching Devices Applications

Abstract

AbstractThin films of vanadium dioxide (VO2) exhibit an interesting semiconductor to metal transition (SMT) when heated above ˜680C in which its resistivity changes by 3-4 orders of magnitude and its transmittance for IR wavelengths drops drastically. Integration of these thin films with Si (100) substrate is of immense technological importance due to its potential applications in sensor and memory based devices. Using pulsed laser deposition (PLD) we have demonstrated in this study that thin films of VO2 can be grown epitaxially on Si (100) substrate using an intermediate tetragonal Yttrium-Stabilized Zirconia (YSZ) layer without any further annealing. X-ray diffraction (XRD) and cross-section transmission electron microscopy studies were performed on the films and they are found to be of highly epitaxial nature. Electrical resistivity measurement were carried out using the four-point probe method and SMT parameters were extracted using Gaussian fit of the data. The S-M transition parameters are in close proximity with parameters obtained from vanadium oxide films deposited on oxide based substrates such as Al2O3 or TiO2.