Investigation of deposition parameters on the structural properties and hardness of TiAlN films deposited via reactive pulsed DC magnetron sputteringInvestigation of deposition parameters on structural properties and hardness of TiAlN films deposited by reactive pulsed DC magnetron sputtering

Abstract

In this work, titanium aluminum nitride (TiAlN) films were deposited on a silicon substrate via reactive pulsed DC magnetron sputtering. The effect of deposition parameters such as nitrogen gas flow rate, substrate temperature, and bias voltage on the structural and mechanical properties of TiAlN films was investigated. The crystal structure, morphology, and hardness of TiAlN films were characterized via X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM, and nanoindentation. An improved crystallinity of TiAlN films was obtained by varying the substrate temperature and bias voltage. The morphology of the TiAlN film exhibited a columnar structure, and the morphology gradually changed with the increase in bias voltage. The films thickness decreased upon increasing the nitrogen gas flow rate, substrate temperature, and bias voltage. In addition, the hardness of the TiAlN film was enhanced by adjusting the nitrogen gas flow rate, substrate temperature, and bias voltage, and a suitable elemental component ratio was obtained. A maximum hardness of approximately 28.9 GPa was obtained for the TiAlN film with a nitrogen gas flow rate of 4 sccm, substrate temperature of 500ºC, bias voltage of 100 V, and an elemental composition Al/(Al + Ti) of approximately 34.35%.