A Low Actuation Voltage Capacitive RF MEMS Switch

A low actuation voltage capacitive RF MEMS switch is demonstrated in this paper Compared with ordinary bending deflection RF MEMS switch, this switch has folded suspending beams and torsion springs, which can make the actuation voltage of the RF MEMS capacitive switches depressed obviously. The simulation results show that the actuation voltage can be affected by the t(1) (the thickness of the top membrane), to (the thickness of the Si3N4 layer) and go (the initial height between the top membrane and dielectric). Additionally, the holes on the membrane can affect the property of the switch, such as the actuation voltage, the insertion loss and the isolation. Finally, a length 300um, width 120um RF MEMS switch with 5umx5um holes on the 60umx120um membrane is designed and simulated. The simulation results show that the actuation voltage of RF MEMS switch is about 4V with t(1)=0.8 urn, t(0)=0.3 um and g(0)=2 um, the resonant frequency is as high as 10(4)Hz.