Structural and plasmonic properties of Ti _x Zr _1−x N _y ternary nitride thin films

Nitride is a kind of alternative promising plasmonic material, and ternary nitride can provide the high diversity and tunability of the plasmonic performance. In this work, Ti _x Zr _1−x N _y ternary nitride films were prepared by magnetron co-sputtering method, and the effects of metal content and nitrogen content on the structural and plasmonic properties of the films were investigated. The results show that the films are fcc-structured and (1 1 1)-orientated. The alloying of the ZrN and TiN can enlarger the grain size of the films, while the over-stoichiometric nitrogen atoms can depress the crystallinity. The crossover frequency ω _c and energy loss of the Ti _x Zr _1−x N _y ternary nitride films are lower than those of the binary TiN _y and ZrN _y . Increasing N-content can also reduce the energy loss of films. For the films with moderate N-content, the plasma factors Q _SPP and the Q _LSPR of ternary nitride films is comparable to that of TiN films. An increase in nitrogen content reduces the Q _LSPR and Q _SPP factors. The absorption edge and optical band-gap can be narrowed by the increasing of Ti or N-content. These results demonstrate that Ti _x Zr _1−x N _y ternary nitride film can be used as an alternative plasma material and their plasmonic properties can be modulated over a wide range by composition.