A MEMS capacitor with improved RF power handling capability

This paper presents a structure of MEMS capacitor providing independence of its nominal capacity and tuning range from the applied RF signal power. The capacitor includes a third parallel plate acting as an electrode to which an extra DC voltage is applied to compensate for the self-actuation effect. This means that the device can be used in many applications working under different RF power conditions, without changing its performance - nominal capacity and tuning range. Capacitor design concept and simulations are provided. It has been manufactured using a standard surface-micromachining MEMS technology. Experimental results are presented, validating the concept and demonstrating its feasibility and advantages.