A fluoro-ethoxysilane-based stiction-free release process for submicron gap MEMS
 
A fluoro-ethoxysilane-based stiction-free release process for submicron gap MEMS 
 
Bertrand Parvais, A. Pallandre, A. M. Jonas, J. P. Raskin
 
Abstract 

Nowadays, stiction remains one of the biggest reliability problems in the fabrication of micro- electromechanical systems (MEMS), especially when a small gap is used. To avoid the adhesion, a Self-Assembled Monolayer (SAM) could be coated. Main research in that field focuses on aliphatic chloro-silanes. We developed a novel wet-release CMOS compatible process for the fabrication of surface-micromachined beams using a perfluorated SAM. Uniform 9 {\AA} thick monolayers were observed. A static contact angle of 117° up to 300°C was measured. Furthermore, a complete 1μm thick (gap 0.5μm) polysilicon RF MEMS capacitor with aluminium interconnects realized with this process demonstrated the CMOS compatibility.