Integration of tunable capacitors and bonded-wires for contactless RF switch and tunable filter

This paper describes a contactless RF MEMS switch, composed of two surface-micromachined tunable capacitors and two bonded-wire inductors, which can achieve a power isolation ratio of 10 dB with a capacitance variation of mere 4:1 over a narrow bandwidth near 2.4 GHz. This novel approach of using inductors eases the deflection requirement for the deformable bridge for the variable capacitor, and allows piezoelectric ZnO film to be used to deflect the capacitor bridge to vary the air gap, thus yielding a contactless RF switch.