All-metal high-isolation series and series/shunt MEMS switches

This paper presents a novel all-metal series switch with several different pull-down electrode geometries. The switch results in an up-state capacitan ce of 5-9 fF and an isolation of - 25 to -30 dB at 10 GHz. The fabrication process is completely compatible with the standard capacitive (or de-contac t) shunt switch. A dc-40 GHz series/shunt switch is also presented with an isolation of -60 dB at 5 GHz and -42 dB at 10 GHz. This is the highest isol ation switch available to-date. The performance is limited by radiation in the CPW lines and not by the series/shunt switch characteristics. The appli cation areas are in high-isolation switches for basestations and satellite systems.