4-Terminal MEMS relay with an extremely low contact resistance employing a novel one-contact design

This paper reports a unique 4-terminal MEMS relay (actuation is electrically isolated with signal passage) employing a novel one-contact design to overcome high contact resistance problem of the conventional 4-terminal MEMS relay which utilizes a typical two-contact design. The fabricated 4-terminal MEMS relay with the one-contact design demonstrated a contact resistance of 18 mΩ, which is two order-of-magnitude lower value than that of the conventional two-contact design. To the best of our knowledge, this result is the lowest value in the 4-terminal MEMS relay and comparable value with the state-of-the-art in 3-terminal MEMS relay [14]. In addition, the relay was operated up to 1.1 x 10⁶ cycles at 1 V / 50 mA in an air and hot switching condition with negligible contact resistance variation. The lifetime is 10 times longer than that of the conventional 4-terminal MEMS relay.