Probing the role of C + ion energy, thickness and graded structure on the functional and microstructural characteristics of ultrathin carbon films (<2nm)

We report a comprehensive study on the protective, functional and microstructural properties of filtered cathodic vacuum arc (FCVA) deposited ultrathin carbon overcoats (COCs), which are being considered as potential candidates for future media recording technology such as heat-assisted magnetic recording (HAMR). Specifically, the influence of the C+ ion energy (50–345eV) and the film thickness (0.5–3.2nm) on these properties were investigated and supported with Raman and X-ray photoelectron spectroscopy (XPS). Finally, an optimized deposition recipe has been proposed to develop an ultrathin (≤2.0nm) yet continuous COC with improved wear and corrosion resistance compared to thicker conventional COCs (~2.7nm).