Surface contamination on sputter carbon coated disks measured by using low energy photoelectron spectroscopy in an ambient atmosphere

The influence of surface contamination on sputtered carbon films on a rigid thin-film disk was evaluated with LEPS (low-energy photoelectron spectroscopy) and XPS (X-ray photoelectron spectroscopy). LEPS was as sensitive as XPS for detecting the surface contaminant. LEPS had the advantage of operating in an ambient atmosphere, while XPS was useful for the identification of the chemical species of the contaminant. The XPS analysis revealed that the main contaminant was due to water in air. XPS showed that the wettability of the fluorocarbon lubricant decreased with an increase in the exposure time of the sputtered carbon film to air before lubrication or with a surface-contaminant increase on the sputtered carbon film