Design of millimeter-wave reconfigurable bandstop filter using CMOS-MEMS technology

The design of band reconfigurable CMOS-MEMS bandstop filter is proposed in this work. The stopband is switchable when driving comb-fingers mechanical structure to change the open-stub capacitance. The actuator is constructed by numerous parallel beams which are connected by a central pole to create a fishbone-like structure. Therefore, the static electricity force can be increased owing to multiple beams so that the driven voltage can be dramatically reduces. The measurement results show that the resonant frequency is tuned from 60 GHz to 50 GHz and isolation in both cases is better than 35 dB. This device was fabricated using TSMC 0.35-μm CMOS-MEMS process with chip size of 0.765 × 0.98 mm².