DC-contact RF MEMS switches with bias physically insulated from RF signal

Cantilever beam DC-contact RF MEMS switches, with bias electrodes physically insulated from the RF/microwave transmission line (t-line), have been developed for broadband communication system applications. The paper presents the design, optimization and equivalent circuit model for the MEMS switches. The beam is composed of multilayer thin films formed by a slightly tensile stressed dielectric and metal layer. A MEMS switch sample has been fabricated based on a low temperature surface micromachining process. On-wafer measurement results are as follows: insertion loss less than 0.8 dB; isolation more than 26 dB at 0.1-26 GHz; applied voltage 30-80 V.