Design and Simulation of Low Actuation Voltage RF MEMS Ohmic Switch with Different Flexures

Abstract

RF MEMS switches are microscale devices used in a wide range of applications from military to commercial RF systems. In this paper a design and simulation of RF MEMS ohmic switches with three different spring flexure designs namely Quasi-Concertina, Double Beam Suspension and Rounded Meander flexure was done and a comparison was done on various performance indexes. The flexures exhibited a peak simulated stress well below the ultimate tensile strength of gold. The simulated pull-in voltages are 2.4063V, 1.3789 V, 1.3403V for Quasi-Concertina, Double Beam Suspension, and Rounded Meander flexures respectively. The simulated switching times are 70μs, 101μs and 103μs for the Quasi-Concertina, Double Beam Suspension and the Rounded Meander respectively. The three switch designs have greater than -42dB return loss at 8GHz and greater than -35dB return loss at 40GHz. The three proposed switch designs show less than -0.04dB insertion loss at 40GHz, the three designs show a peak of -77dB isolation at 1MHz frequency and -15dB isolation at 16GHz. The three designed ohmic switches are applicable in the DC-Ku(18GHz) range.