Evaluation of mechanical and antibacterial properties of Cu-DLC composite films

Diamond-like carbon (DLC) films had been formed as a surface treatment for intracorporal device for decreasing the coefficient of friction. DLC film showed significant stability without being damaged during acid immersion and high-pressure steam sterilization. However, bacteria that adhere to medical devices lead to the induction of infectious diseases associated with therapeutic actions. Therefore, maintenance of a hygienic surface condition has been strictly required. This study demonstrated the fabrication of DLC films (gas source: CH4), which incorporated Cu (Cu-DLC). The Cu-DLC films were synthesized on a Si (100) substrate via plasma-enhanced chemical vapor deposition and magnetron sputtering. The surface morphology, microstructure, element contents, wear resistance, hardness, and antibacterial properties of the films were experimentally analyzed. Cu particles were considered not uniformly distributed in the DLC film, they embedded in DLC films formed a three-dimensional structure led to higher roughness. The Cu-DLC exhibited wear resistance and higher hardness compared to Cu. After inoculation, Cu-DLC films showed higher antibacterial activity against E. coli than pure DLC. It is expected that the hygienic films with excellent mechanical properties demonstrated in the present study will be utilized in various medical and industrial sectors.