11 January 2008 RF MEMS switches: design and performance in wireless applications
Author Affiliations +
A road map has been proposed for the design methodology of a RF MEMS switch. The design methodology for RF MEMS is often an interactive process which involves continuous adjustments for the specifications, structure and the fabrication steps. This helps in defining and obtaining the required RF microwave specifications. A novel RF MEMS D shape capacitive shunt switch is proposed. The switch structure is fabricated on a high resistive silicon substrate. This structure consists of coplanar waveguide transmission line, a D shape lower electrode with thin dielectric layer on top and suspended membrane bridge. The lower electrode of the switch is fabricated in D shape using high viscosity and high conductive adhesives. The switch RF path is fabricated on top of silicon dioxide using a thick coplanar waveguide transmission line. The thick transmission line metal connects to the lower electrode and the dielectric material to form the through path of a shunt switch. The suspended metal membrane spans the two coplanar ground lines. With no applied actuation voltage the residual tensile stress keeps the membrane suspended above the RF path. By applying an electrostatic field between membrane and the lower electrode an attractive force causes the floating membrane to pull down and make contact with the lower electrode and dielectric surface to form a low impedance RF path to ground. Main area to which the development aims is lowering the actuation voltage to levels compatible with mainstream IC technologies, while maintaining the RF performance. Proposed switch has shown satisfactory performance between 0-40 GHz frequency range. Paper will present simulation and theoretical results. Experimental results of conductive epoxy fabrication are also presented. This switch could have an important application in the telecommunication network like switching networks.
© (2008) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Hamood Ur Rahman, Jafar Babaei, Rodica Ramer, "RF MEMS switches: design and performance in wireless applications", Proc. SPIE 6800, Device and Process Technologies for Microelectronics, MEMS, Photonics, and Nanotechnology IV, 680027 (11 January 2008); doi: 10.1117/12.769359; https://doi.org/10.1117/12.769359

Back to Top