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Synthesis of nanocomposite thin films of CrN/Cu on (100) Si and titanium modified stainless steel (D-9 alloy) substrates by pulsed magnetron sputtering from a composite target of Cr-Cu using sputtering gas mixture of argon and nitrogen is investigated. X-ray diffraction analysis of the films deposited at 773 K and 10 sccm of nitrogen flowrate indicated that the films are nanocrystalline and biphasic (fcc CrN and fcc Cu). The films showed a peak hardness of y15 GPa and a Young's modulus of y200 GPa for those with a copper content of 15?1 at-%, and these values were found to decrease significantly with a Cu content of >18?4 at-%. The evaluation of the antibacterial activity as a function of copper content in the range of 15?1-38?5 at-% indicated excellent antibacterial properties for CrN/Cu films with the copper content of 18?4 at-%. The phase stability of CrN of the nanocomposite is also discussed in relation to pure CrN thin films.

Nanocrystalline zinc oxide (nc-ZnO) thin films were grown on p-type silicon substrate through spin coating by sol-gel process using different sol concentrations (10 wt.%, 15 wt.%, and 25 wt.%). These films were characterized by high resolution nondestructive X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDS) attachment, and electron paramagnetic resonance (EPR) techniques to understand variations in structural, morphological, and oxygen vacancy with respect to sol concentration. The film surface morphology changes from nanowall to nanorods on increasing sol concentration. EPR spectra revealed the systematic variation from ferromagnetic to paramagnetic nature in these nc-ZnO films. The broad EPR resonance signal arising from the strong dipolar-dipolar interactions among impurity defects present in nc-ZnO film deposited from 10 wt.% sol has been observed and a single strong narrow resonance signal pertaining to oxygen vacancies is obtained in 25 wt.% sol derived nc-ZnO film. The concentrations of impurity defects and oxygen vacancies are evaluated from EPR spectra, necessary for efficient optoelectronic devices development.