Measurement of Mechanical Properties of VO2 Films by Nanoindentation

The present work reported the intrinsic mechanical behavior of vanadium dioxide (VO2) thin film deposited on a SiO2 substrate using a combination of nanoindentation tests and a theoretical model. The effect of phase transition on mechanical parameters was studied by adjusting the test temperature. A new model that can simultaneously extract the elastic modulus and hardness was derived by introducing a dimensional analysis. The results showed that the thin film exhibits a hardness of 9.43 GPa and a Young's modulus of about 138.5 GPa at room temperature, compared with the values of 5.71 GPa and 126.9 GPa at a high temperature, respectively. It can be seen that the intrinsic mechanical parameters decrease to a certain extent after a phase transition. Finally, the numerical simulation results were consistent with those of the experiments, which verified the effectiveness of the new method. In addition, this study also provided useful guidance for mechanical tests on other ultra-thin films.

Automated summary

This work investigates the mechanical behavior of vanadium dioxide (VO2) thin film on a SiO2 substrate through nanoindentation tests and a theoretical model. The effect of phase transition on mechanical parameters was examined by varying the test temperature. A new model that can extract both the elastic modulus and hardness was developed. The results show a decrease in the intrinsic mechanical parameters after the phase transition. Numerical simulation results are consistent with experimental findings, validating the effectiveness of the new method. This study also provides valuable guidance for mechanical testing of other ultra-thin films.