Cantilever beam designs for RF MEMS switches

This paper presents the design, modeling, fabrication and measurements of two novel radio frequency microelectromechanical systems (RF MEMS) switches. Two new non-standard cantilever beams have been designed in order to validate the mathematical model developed for the calculation of the spring constant and to verify the fabrication parameters. The mechanical modeling is based on the Euler-Bernoulli beam equations. The fabricated switches using these cantilever beams exhibit 19 V and 23 V actuation voltages. The fabrication consists of a six-mask all-metal process. A unique dry-release technique is also described. The RF simulations and measurements of these switches are finally presented. The isolation is better than 23 dB and 27 dB and the return loss is better than 19 dB and 18 dB, from 0 to 40 GHz. The insertion loss is 1.15 dB and 1.3 dB for the two designs, respectively, for all frequency bands of interest.