Design of Novel Capacitive RF MEMS Shunt Switch with Aluminum Nitride (AlN) Dielectric

In this paper, design of novel capacitive RF microelectromechanical systems (MEMS) shunt switch with butterfly structured beam is presented to reduce the actuation voltage. With aluminum nitride (AlN) dielectric layer the RF characteristics of designed switch renders the excellent performance over 5 GHz to 60 GHz frequency. The reported capacitance ratio of switch maximum 125 at 3 um air gap. The realized switch exhibit low actuation voltages, in the range of 3-10 volts, an insertion loss of 0.5 dB, and return loss of greater than 17 dB over operating frequency range 5-60 GHz, and an isolation loss greater than 20 dB over operating frequency range 10-60 GHZ. The characterization of proposed switch actuation voltage has been compared with straight and meander type supported beams and at a different air gap. Improved isolation loss of aluminium dielectric layered based switch has been compared with silicon dioxide (SiO2) and silicon nitride (Si3N4) dielectric layers. The electromechanical analysis and electromagnetic analysis simulations ware carried out by 3D MEMS commercial software package, Intellisuite and full wave electromagnetic simulator, Ansoft HFSS respectively for designed switches.