Dual Membrane Multiport DC-40 GHz RF Microelectromechanical Switches

This article reports unique dual membrane multi-port DC-40 GHz radio frequency (RF) microelectromechanical switches. A single-pole double-throw (SPDT) design is presented with a metal-to-metal contact switch in series with a capacitive membrane to achieve better isolation performance over the entire operational range. The switches are fabricated using a seven-layer UWMEMS microfabrication process on alumina substrate and the electromagnetic modeling of the switches is discussed in detail. Full field 3D model is developed to include conformal thin-film discontinuities and the material database for the simulations are characterized and extracted experimentally. At 20 GHz, the presented switch topology demonstrate better than 0.35 dB of insertion loss and higher than 40 dB isolation performance.