Precise control of surface texture on carbon film by ion etching through filter: Optimization of texture size for improving tribological behavior

Surface texture is a potential way to promote the tribological behavior of films with a range of tens to hundreds nanometers, but how to precisely control the texture size and find an optimal size for improving the tribological behavior is still challenging. In this paper, we proposed a method to fabricate pit texture with tunable size on the surface of carbon film by ion etching through a filter. The pit depth (10, 30 and 60 nm) was decided by the etching time and the pit diameter (10, 60 and 120 μm) was equal to the through-hole on the filter. The tribological properties of these carbon films were tested using a pin-on-disk tribometer. The results demonstrated that the friction coefficient and wear life were strongly affected by the texture parameter and there were an optimal pit depth and diameter under which the film exhibited the lowest friction coefficient and the longest wear life. The mechanism of the tribological property promotion was further discussed based on the variation of the transfer film structure and contact condition induced by the texture. These results provided an effective way to choose proper texture parameters for better tribological performance of the surface, which can be expected for expanding the texture techniques.