Microfabrication issues in constructing freestanding membranes of near-frictionless carbon and diamond-like films

The near-frictionless carbon (NFC) film developed at Argonne National Laboratory has excellent mechanical and tribological properties, such as the super low friction coefficient of 0.001 and the wear rates of 10− 11–10− 10 mm3/N m. In this study, microfabrication procedures are developed to fashion the NFC thin films into freestanding structures which are necessary for many MEMS sensor devices. The entire microfabrication process is outlined in detail for use by other researchers. The NFC membranes were characterized with optical, scanning electron, and atomic force microscopy and Raman spectroscopy both before and after the fabrication process to observe any structural changes. Several surface and bulk micromachining issues, such as reactive ion notching effect and NFC film releasing, were studied and mitigated.