Structure and Properties of Nanocrystalline (TiZr)_xN_1−xThin Films Deposited by DC Unbalanced Magnetron Sputtering

Abstract

This study aims to investigate the effects of nitrogen flow rate (0–2.5 sccm) on the structure and properties of TiZrN films. Nanocrystalline TiZrN thin films were deposited on Si (001) substrates by unbalanced magnetron sputtering. The major effects of the nitrogen flow rate were on the phase, texture, N/(Ti + Zr) ratio, thickness, hardness, residual stress, and resistivity of the TiZrN films. The nitrogen content played an important role in the phase transition. With increasing nitrogen flow rate, the phase changed from mixed TiZr and TiZrN phases to a single TiZrN phase. The X-ray diffraction results indicated that (111) was the preferred orientation for all TiZrN specimens. The N/(Ti + Zr) ratio of the TiZrN films first increased with increasing nitrogen flow rate and then stabilized when the flow rate further increased. When the nitrogen flow rate increased from 0.4 to 1.0 sccm, the hardness and residual stress of the TiZrN thin film increased, whereas the electrical resistivity decreased. None of the properties of the TiZrN thin films changed with nitrogen flow rate above 1.0 sccm because the films contained a stable single phase (TiZrN). At high nitrogen flow rates (1.0–2.5 sccm), the average hardness and resistivity of the TiZrN thin films were approximately 36 GPa and 36.5 μ Ω·cm, respectively.