RF MEMS switch for Reconfigurable RF-Front End with Improved Hot-Switching Capabilities

This paper reviews the authors' past work on how to improve the hot-switching reliability for RF MEMS switch. Two methods have been proposed to improve the hot-switching reliability. The first method is to place a refractory sacrificial metal contact in parallel with the main low-resistance switch contact. The sacrificial contact will be actuated first to significantly lower the electric field strength across the main contact during hot-switching. Both sacrificial contact and main contact are integrated in a compact single cantilever actuator. The performance is demonstrated experimentally, by showing 100 times improvement of reliability in hot-switching cycle. The second method is to place the sacrificial contact in front of the main switch contact in shunt configuration. The sacrificial contact will be actuated first to block the incoming RF power while the main switch contact is switching. The main switch contact will be immune to hot-switching RF power damage. The proposed method is experimentally verified to yield better reliability. In addition to the improved reliability, the isolation of the switch is also improved, mainly due to the shunt sacrificial switch.