DC-Contact RF MEMS Switches using Thin-Film Cantilevers

This paper describes the development of DC-contact RF-MEMS SPST, SP3T, and SP4T switches implemented with a thin-film cantilever. Using aluminium as the sacrificial layer in the fabrication process, flat cantilevers are realized with a measured actuation voltage of 50~70 V. The SPST switch is used as a building block to realize more complicated SP3T and SP4T switches for use in true-time delay phase shifters. The preliminary measurements of the SP3T and SP4T switches demonstrate isolation of 20 dB and insertion loss less than 2 dB up to 50 GHz.