Structural and dielectric properties of ion beam deposited titanium oxynitride thin films

Titanium oxynitride (TiO _xN _y) thin films were fabricated by ion beam-assisted sputtering deposition. Effects of oxygen contribution, assisting ion energy (E_a), assisting ion beam current (I_a) on the microstructure and dielectric behavior of the films were analyzed. The results show that increasing O content made the films to turn from fcc-TiN (111)-oriented to fcc TiO _xN _y (220)-oriented. Proper E_a and low I_a can enhance the (220) orientation in TiO _xN _y thin films. The increase in oxygen content leads to the red-shift of plasmonic resonant frequency and makes the films more dielectric. Higher E_a and I_a make the TiO _xN _y films more metallic. Atomic composition is an important factor underlying the results. The study provides a method to control the plasmonic properties of oxynitride films in a wide range by atomic composition and assisting ions.