Tailoring the phase transition of VO2 thin films via cobalt doping and secondary phase incorporation

Vanadium dioxide (VO2) is a prominent phase transition material with strongly correlated electron behavior, exhibiting unique physical properties and significant potential for electronic applications. Tuning the phase transition characteristics of VO2 is one of the major directions for such a material. In this study, ferromagnetic transition metal element cobalt (Co) has been introduced into VO2, in the form of direct doping or incorporation as a secondary phase, to fine-tune the critical temperature (TC) of VO2 films, which results in a wide tuning range of 341.94–327.35 K for the former and 342.16–315.09 K for the latter. Comprehensive characterizations, including structural and spectroscopic analyses, were conducted to explore the intricate relationship between the structural modifications and the resulting phase transition behaviors. The insights gained from these investigations provide a deeper understanding of phase transition tuning in VO2 thin films and broaden the material's potential for advanced device integration.