Trap wave method for high isolation series RF MEMS switches application

This paper presents a trap wave circuit structure to compensate for the coupled capacitance, to increase the switch isolation. The switch is first accurately modeled using numerical and experimental techniques, and its equivalent capacitance model is derived, then the comb capacitance-spiral inductance trap wave circuit is derived using RF circuit simulation software. The layout of the structure can be realized with no extra fabrication processes. Theoretical analysis shows that the isolation can be improved by 15.6 dB, but the insertion loss is only affected by 0.07 dB, in the frequency range from 2-5 GHz, when this method is applied.