Structural, plasmonic and electronic properties of zirconium carbonitride thin films prepared by dual ion beam deposition

Metal carbonitride is a new type of tunable plasmonic materials and can be tuned by nitrogen and carbon content. In this work, zirconium carbonitride (ZrCXNy) thin films are prepared by dual ion beam deposition. The effects of C content and assisting ions on the structure and plasmonic properties of the films are studied. The results show that all the films are in B1-structure. C content increasing can reduce the shielding plasma frequency h?( c) and the carrier concentration of the film. Appropriate assisting ion beam energy E-a and current density J(a) can promote the crystallinity of the film. As E-a and Ja increases, h? (c) increases initially and then decreases. The effects of the assisting ions can be attributed to the C content and the C-related defects, which is confirmed by the calculation of electronic states. The calculated density of state of the electrons shows that increasing C-substitute defects can decrease the threshold energy of interband transition, and the interstitial C defects lead to the similar effect. The study shows that metal carbonitride is a more tunable plasmonic material in visible and infrared region, and can also be modulated by the assisting ions.