Room temperature fabrication of titanium nitride thin films as plasmonic materials by high-power impulse magnetron sputtering

High-power impulse magnetron sputtering (HiPIMS) was used to deposit titanium nitride (TiN) thin films with high electron density as alternative plasmonic materials. TiN thin films with thicknesses of 20-40 nm were deposited with different average sputtering powers, and exhibited metallic- and dielectric-like optical properties. When the sputtering power was increased from 80 W to 300 W, denser polycrystalline TiN thin films were obtained at room temperature (RT) with a conductivity 25 times that of the low-sputtering-power film. With sufficient average power (≥ 180 W), the films exhibited metallic-like optical properties, and a conductivity of >10⁵ S/m. By using HiPIMS deposition, good-quality metallic-like TiN thin films could be fabricated at RT without heating the substrate.