Monolithic MEMS T-type Switch for Redundancy Switch Matrix Applications

This paper presents a novel approach to monolithically implementing RF MEMS T-type switches for redundancy switch matrix applications. The T-type switch performs three operational states: two turning states and one crossover state. A six-mask fabrication process is adapted to fabricate the proposed design. Novel RF circuits were used to implement the entire system, including series contact cantilever beams, RF crossover, 90 degree turns and four-port cross junctions. The measured results for the entire T-type switch demonstrate an insertion loss of 1.5 dB, a return loss of better than -20 dB and an isolation higher than 28 dB for all states for frequencies up to 30 GHz. To our knowledge, this is the first time an RF MEMS T-type switch has ever been reported.