An active heat-based restoring mechanism for high reliability RF-MEMS switches

An active mechanism to retrieve the functionality of RF-MEMS ohmic switches after stiction takes place is discussed. The mechanism exploits a micro-heater, embedded within the switch topology, to induce restoring forces on the stuck membrane, triggered by thermal expansion, when an electric current is driven through it. The experimental investigations prove that driving pulsed (rather than DC) current into the heater enables a successful release of the tested RF-MEMS stuck devices. The release of stuck RF-MEMS ohmic switches is demonstrated for a cantilever-type micro-relay. The mechanism is suitable for a large variety of switch topologies, and can be embedded with small changes and effort within most of the already existing RF-MEMS ohmic switches, increasing, in turn, their reliability.