Residue-Free Dry Etching of Polymer Sacrificial Layer for Microelectromechanical-System Device Fabrication

Residue-free dry etching of a photosensitive-polymer sacrificial layer using O-2/CF4/CO-plasma exposure is described for the fabrication of microelectromechanical-system (MEMS) devices. Energy dispersive X-ray spectroscopy reveals that O-2/CF4/CO-plasma exposure removes polymer sacrificial layers without leaving residue and severely damaging Au structures. Since the O-2/CF4/CO-plasma exposure hardly damages Au structures, this process is applicable for the removal of sacrificial layers for MEMS with Au structures.