Electrical switching in VO 2 sol–gel films

Vanadium dioxide thin films have been made from vanadium oxoalkoxides. The precursor solution is spin-coated onto a silica substrate and heated under a reducing atmosphere. These VO2 films exhibit well known insulator–metal transition at around 67 °C. Electrical switches have been made from such films that reversibly switch from an OFF state to an ON state upon applying a voltage of ca. 50 V. This thermally driven process is fast and highly reversible. More than 108 cycles have been performed without failure.