Study on microstructure, optical and tribological properties of self-formed Ta oxide films

Ta2O5 films were deposited on glass and silicon substrates by magnetron sputtering with different power. The microstructure of Ta2O5 films was studied by XRD, SEM, EDS, XPS and AFM. The mechanical and tribological properties of Ta2O5 thin films were studied by ultraviolet-visible spectrophotometer, nanoindentation and friction and wear tester. The sputtering power has a significant effect on the surface morphology of Ta2O5 films. The transmittance of the film decreases with the increase of sputtering power. The optical band gap of the film fluctuates with the change of sputtering power. This is related to the packing density of the sputtered particles and the oxygen vacancies in the film. The wear forms of Ta2O5 films prepared under different sputtering power conditions are mainly fatigue wear and adhesive wear. The optical properties of Ta2O5 films are more sensitive to the change of sputtering power. Ta2O5 films with good optical and tribological properties can be obtained under appropriate process conditions.