Structural, mechanical and corrosion properties of NbN films deposited using dc and pulsed dc reactive magnetron sputtering

NbN thin films were deposited onto silicon wafer and M2 tool steel substrates using dc and pulsed dc reactive magnetron sputtering at 1.5, 2.5 and 3.5 A of target currents. The films were characterised using X-ray diffraction, scanning electron microscopy, microhardness, scratch adhesion tester and potentiodynamic polarisation techniques. The analysis revealed that the structural characteristics, mechanical and corrosion properties of NbN films depend on both deposition mode and target current. With increase in target current, all the films exhibited better structural, mechanical and corrosion properties for both modes. The results indicated that NbN films deposited using pulsed dc magnetron sputtering consistently outperform those deposited using dc magnetron sputtering.