Design and development of miniaturized high isolation MEMS SPDT switch for Ku-band T/R module application

The design, development and characterization of single-pole-double-through (SPDT) switch using micro electromechanical systems based inline-metal contact switch is presented in this paper. The switch employs electrostatic actuation and is implemented using coplanar waveguide. The design is based on the series-shunt configuration consisting of six cantilever type switches. The main objective of the present study is to achieve high-isolation, good input/output match, low insertion loss and small size to fit into Ku-band transmit/receive module. The device has been fabricated using gold based surface micromachining process. The mechanical, electrical, transient, intermodulation distortion and loss performance of MEMS switch have been experimentally investigated and validated. Measured return loss of better than 22dB with worst case insertion loss of 1.4 dB and isolation greater than 45dB have been experimentally achieved from SPDT switch over 13-17 GHz. The total switch area is 1.25 mm². The performance of the switch is finally compared with the present state-of-the-art.