Effect of Mid-Frequency and Inductively Coupled Plasma on the Properties of Molybdenum Nitride Thin Films

This study focuses on the characterization of MoN thin films deposited by the direct current magnetron sputtering (dcMS), mid-frequency magnetron sputtering (mfMS), and inductively coupled plasma magnetron sputtering (ICPMS) methods. Two mixed metallic phases, namely, α-Mo and γ-Mo2N, were detected from the film obtained using the dcMS, whereas only single γ-Mo2N phase was detected from the films obtained using the mfMS and ICPMS. Furthermore, the residual stress of the deposited thin films was strongly dependent on the sputtering process. As the mfMS and ICPMS deposition process were introduced, the film morphology changed from a porous columnar to a dense structure with finer grains than film deposited using dcMS. The surface roughness and crystal grain size of coated films were investigated by atomic force microscopy and X-ray diffraction analysis methods. Furthermore, the variation in hardness and electrical resistivity of the MoN thin films deposited by three plasma-enhanced magnetron sputtering was explained on the basis of microstructure and residual stress of the thin films.