Deposition and patterning of diamondlike carbon as antiwear nanoimprint templates

Abstract

In this work, antiwear nanoimprint templates were made by depositing and patterning diamondlike carbon (DLC) films on Si and quartz. A capacitively coupled plasma enhanced chemical vapor deposition (PECVD) system was configured to deposit $100\mathrm{nm}–1\mu \mathrm{m}$ thick DLC films on Si and quartz substrates. These films were characterized with Raman spectroscopy, electron energy loss spectroscopy, atomic force microscopy, nanoindentation, contact angle measurements, and optical transmission measurements. The rf power and pressure of the PECVD process were varied to obtain uniform coating of DLC films with smooth surface ($\sim 0.2\mathrm{nm}$ rms), low surface energy $(\sim 40\mathrm{mJ}∕{\mathrm{m}}^2)$ , and high hardness $(\sim 22\mathrm{GPa})$ . The resulting films’ wear resistance is more than three times better than quartz. The DLC films were patterned by nanoimprint lithography using polymethylmethacrylate (PMMA) followed by $\mathrm{C}{\mathrm{F}}_4$ plasma etch. Thermal nanoimprint tests with DLC templates were performed in PMMA. Atomic force microscopy measurements indicated excellent pattern-transfer fidelity and template-polymer separation.