High power impulse magnetron sputtering (HiPIMS) for the fabrication of antimicrobial and transparent TiO₂ thin films

Titanium dioxide thin film has been widely studied and applied because of its excellent photocatalytic, antimicrobial, and optical performance. The application of TiO₂ films as the antibacterial and transparent coatings deposited on touch screens and touch panels by sputtering methods for preventing the infection of microorganisms is required. The high power impulse magnetron sputtering (HiPIMS) technique is characterized by its ability to fabricate oxide thin films with dense microstructure and better film quality. In this work, critical processing parameters including, target poisoning ratio/oxygen gas flow rate, peak power density, substrate bias, substrate heating temperature, and gas pressure for achieving high antimicrobial ability, transparent and anatase rich TiO₂ films with more {001} facets by HiPIMS and by the superimposed HiPIMS and medium frequency (MF) magnetron sputtering techniques were discussed. This review explores the HiPIMS and superimposed HiPIMS-MF deposition approaches to produce the TiO₂ thin films, which exhibit good adhesion (>30 N critical load), high transmittance (>80%), and 100% antimicrobial ability in large-scale production.