Characterization of stiction forces in ultra-clean encapsulated MEMS devices

We show that contact between encapsulated MEMS devices and the bare silicon surrounding sidewalls generally results in a reversible adhesion with a consistent adhesion force. This force is small enough (25 mN) to be overcome by the restoring force of the springs in inertial sensors with resonant frequency above 4 kHz. Therefore, it should be possible to design and build stiction-free inertial sensors in this process - a significant advantage over approaches that rely on deposition, tuning and maintenance of chemical coatings for inertial sensors.