Influence of nitrogen content on the thermal diffusivity of TiN films prepared by magnetron sputtering

ABSTRACT

TiN films with various nitrogen content were deposited using reactive magnetron sputtering system and the influence of TiN film’s microstructure on thermal diffusivity was investigated. The results showed that the titanium nitride film with 40.6–64.0at.% N exhibited a single face-centered cubic (fcc) structure. The density of states calculations of TiNx showed that excess N atoms in TiN matrix weaken the Ti-N bonds. The thermal diffusivity of TiN thin films decreased gradually and reached a stable range with an increase of N content. The minimum thermal diffusivity value was 2.291×10⁻⁶m²/s at 60.2at.% N. This reduction of thermal diffusivity could be attribute to the films’ microstructure, including the increased grain boundaries due to the decrease of grain size, the change of preferential orientation and the increased lattice distortion.

KEYWORDS:

• Magnetron sputtering
• TiN films
• microstructure
• thermal diffusivity

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (51374115, 51574131); and National Key R&D Program of China (2016YFB1100103).