Growth of ultra thin vanadium dioxide thin films using magnetron sputtering

Fangfang Song; B. E. White

paper

Growth of ultra thin vanadium dioxide thin films using magnetron sputtering

arXiv:1608.03911

Abstract

In this work, the results of fabricating ultra thin VO $_{2}$ films on the technologically relevant amorphous SiO $_{2}$ surface using reactive DC magnetron sputtering are presented. Results indicate that a post deposition anneal in low partial pressures of oxygen is an effective way at stabilizing the VO $_{2}$ (M $_{1}$ ) phase on the SiO $_{2}$ surface. VO $_{2}$ films with a thickness of 42nm show a continuous microstructure, and undergo a resistivity change of more than a factor of 200 as the temperature of the film increases above 72 $^{o} C$ . The film shows hysteresis in the metal-insulator transition temperature upon heating and cooling with a width of approximately 8 $^{o}$ C. The resistivity of the low temperature semiconducting phase is found to be thermally activated with an activation energy 0.16 $\pm$ 0.03 $e v$ . Stress measurements using X-ray diffraction indicate that the ultra thin VO $_{2}$ film has a large tensile stress of 2.0 $\pm$ 0.2 $GP a$ . This value agrees well with the calculated thermal stress due to differential thermal expansion between the VO $_{2}$ thin film and silicon substrate. The stress leads to a shift of the metal-insulator transition temperature by approximately 4 $^{o} C$ .