Fabrication and Physical Properties of Thin Films TiNx for Infrared Absorption

This paper reports fabrication, electrical and optical characterization of TiNx thin films formed by reactive magnetron sputtering. The optimized resistivity of the films is applied to build a resonant structure for enhancing infrared absorptivity. The resistivity with 13% N2 at 200 °C is close to the theoretical value 377 Ω/square. The light absorptivity of a multilayer structure (TiNx/ SiNx/Al, SiNx/Al) has been recorded by Fourier Transform Infrared Spectroscopy (FTIR). A dramatic increase has been obtained as compared with the pristine SiNx. The offset of optimal sheet resistance is about 70 Ω/square compared to the theoretical value in the FTIR measurements. The thickness of TiNx and absorption of silicon nitride caused by Si-N vibration are major factors leading to the differences.