Symmetric and Compact Single-Pole Multiple-Throw (SP7T, SP11T) RF MEMS Switches

Abstract

This paper presents extremely compact single-pole multiple-throw radio frequency (RF) microelectromechanical system switches, SP7T and SP11T, based on a symmetric circular switch topology. The switch dimensions are 0.61 mm × 0.61 mm, which is smaller than typical CMOS Si-on-insulator switches. The SP7T and SP11T switches, which are insensitive to stress gradient effects, achieve simulated contact and restoring forces of 0.3-0.4 mN (per a switch) at 90-100 V. The SP7T and SP11T switches also achieve isolation levels of 50-19 dB and 50-17 dB, respectively, and insertion loss of 0.3-1.2 dB and 0.3-1.7 dB, respectively, at 0.1-10 GHz. The measured ON-resistance is 4.5-2.5 at 75-100 V, respectively, in an open environment and limited by contact contamination. The measured switching time is 7-10 μs. Cold-switched reliability tests of SP7T and SP11T switches show greater than 10 8 Hz with an RF power of 0.1-1 W, which is sufficient power handling capability for 3G and 4G systems.[ 2014-0001]Index Terms-Radio frequency microelectromechanical systems (RF MEMS), contact switch, switching networks, metal-contact, electrostatic relay. Fig. 1. (a) Conceptual and (b) cross-sectional view of a symmetric circular switch with a shared center post and shared anchors. 1057-7157

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