Metal-insulator transition of VO2 thin films grown on TiO2 (001) and (110) substrates

The effect of uniaxial stress along the c axis on the metal-insulator transition of VO2 has been studied in the form of epitaxial thin films grown on TiO2 (001) and (110) substrates. A large reduction in the transition temperature T-MI from 341 K for a single crystal to 300 K has been observed in the film on TiO2 (001) where the c-axis length is compressed owing to an epitaxial stress, while the T-MI has been increased to 369 K in the film on TiO2 (110) where the c-axis length is expanded. The correlation between the c-axis length and T-MI is suggested: the shorter c-axis length results in the lower T-MI. (C) 2002 American Institute of Physics.