Cu-based nano-multilayer film produced by HiPIMS for antimicrobial properties and its application in photodetector.

This paper reports on the use of high-power impulse magnetron sputtering to deposit Cu-based nano-multilayer films (CuZrTiAl) on Si wafers and AISI 304 stainless steel. Co-sputtering can be performed using multiple simultaneous targets to decrease the cost of manufacturing alloy targets at industrial scales. Co-sputtering mode allows variations in the power supplied to the various targets to control the intensity of the plasma jets and thereby tailor the composition of the deposited films. Our primary aim in this study was to elucidate the effects of Al target power (from 0.3 to 1.3 kW) on the structure and antibacterial properties of the resulting coatings. Varying the Al target power was shown to alter the chemical composition, layer thickness, and structure. EPMA results revealed that increasing the power from 0.3 to 1.3 kW caused a monotonic increase in Al content from 6.1 to 18.3 at%. Dark-field TEM images revealed that decreasing the period thickness from 8.6 to 4.6 nm caused the ultra-thin film Cu to transform into a single isolated nano-crystal, which facilitated the release of Cu ions to improve antibacterial effects (from 84 % to 99 % for Escherichia coli). This study also demonstrated the recycling of the proposed Cu-based nanoscale multilayer films to fabricate metal-doped ZnO nanowires for use in photodetectors. The photodetector achieved a photocurrent-to-dark-current ratio of 150 when using an LED light source with a wavelength of 365 nm. • The period thickness from 8.6 to 4.6 nm caused the Cu layer to transform into isolated nano-crystals. • Nanocrystals facilitated the release of copper ions and reduced the distance to the surface. • The Cu-based nano-scale multilayer coatings as a replacement for metal nitrates. • To achieve the SDGs, Cu-based nano-scale multilayer coatings were recycled to create ZnO NWs for photodetectors. [ABSTRACT FROM AUTHOR]