SPUTTERING TARGETS AND ANTIMICROBIAL NANOPOWDER THIN LAYERS MADE OF SILVER-DOPED ZINC OXIDE AND PROCESS FOR PREPARING THE SAME

摘要

The invention relates to sputtering targets, to a process for preparing the same and to the use thereof in a process for obtaining antimicrobial nanostructured thin layers on steel carrier, for medical applications. According to the invention, the targets consist of antimicrobial nanopowders of ZnO with hexagonal crystalline structure and average crystallite size of 67 nm, doped with up to 2.8% spherical Ag nanoparticles with an average diameter of 10...20 nm. The process, as claimed by the invention, consists in spark plasma sintering under vacuum for 5...30 min, at the temperature of 600...750°C, at a compression pressure of 30...50 MPa, to obtain sputtering targets as discs with a diameter of 50.8±0.1 mm, a density of 4.8...5.5 g/cm, Vickers micro hardness HV2/15 of 102...280, Young modulus of 30...87 GPa. According to the process, the targets are radio-frequency magnetron sputtered on a stainless steel carrier, in a sputtering enclosure with a start vacuum pressure of 10Pa and a working pressure of 2...4 Pa, at a power of 50 W, with a power growth rate of 10 W/min up to a power value of 100...300 W which is maintained for 30...60 min, at a distance of 10 cm between the target and the carrier, to result in 200...1000 nm-thick antimicrobial nanostructured layers.