Resistivity of V2O3 thin films deposited on a-plane (110) and c-plane (001) sapphire by pulsed laser deposition

Thin films of V(2)O(3) with thickness of 215 nm were grown on a- and c-plane sapphire by pulsed laser deposition with (001)V(2)O(3)parallel to(001)Al(2)O(3) and (110)V(2)O(3)parallel to(110)Al(2)O(3) epitaxy. The effects of the growth direction on the electrical resistivity of the films were examined. Films on c-plane sapphire displayed a metal-to-insulator transition at T=180 K compared to T=160 K in single-crystal V(2)O(3). The films on a-plane sapphire, however, showed an insulator-to-insulator transition at T=186 K. The variation in the phase transformation characteristics and the resistivity can be attributed to different levels of strain and commensurate changes in the film morphology. (C) 2008 American Institute of Physics.