Influence of sputtering atmosphere on crystal quality and electrical properties of zirconium aluminum nitride thin film

• ZrAlN films were prepared by unbalanced DC reactive magnetron co-sputtering.
• Sputtering atmosphere greatly influences ZrAlN microstructure and properties.
• ZrAlN film shows superior insulating and dielectric properties than pure AlN.

Zirconium aluminum nitride thin films (Zr0.11Al0.89N) were prepared on different substrates using unbalanced DC reactive magnetron co-sputtering. The influence of sputtering atmosphere, including N2/Ar-flow ratio and their total pressure, on the crystalline structure and the electrical properties of the Zr0.11Al0.89N films has been investigated. In this work, the optimal N2/Ar-flow ratio is 1:1 and the optimal total pressure is 0.5 Pa. The resultant Zr0.11Al0.89N films have a wurtzite structure that is preferentially oriented along the c-axis and have uniform grains. The dielectric constant, dielectric loss, leakage current density and resistivity of the Zr0.11Al0.89N films reach ~ 16, ~ 0.01 (in a frequency range of 103–106 Hz), 3.0 × 10− 8 A/cm2 and 1.92 × 1012 Ω·cm, respectively, which are all superior to those under suboptimal conditions. Moreover, the Zr0.11Al0.89N films exhibit higher dielectric constants, as well as much lower dielectric loss and leakage current density compared to that of pure AlN films.