Optical properties at the metal-insulator transition in thermochromic VO2−xFx thin films

Thermochromic VO2−xFx thin films were prepared by reactive rf magnetron sputtering followed by annealing post-treatment. Electrical and optical properties were measured as a function of temperature. The transmittance and reflectance were essentially wavelength independent at 65 °C, i.e., at the metal-insulator transition.