Low Actuation Voltage, Good RF Characteristics RF MEMS Switch with Using Π-Structure

This paper presents design of an electrostatic capacitive shunt coupling RF microelectromechanical system (MEMS) switch with low actuation voltage suitable for Q-V band application. Design and analysis of the RF MEMS switch are based on both the finite element method and the full wave electromagnetic simulation. According to the electrical model, a single beam switch and double beam switch with serpentine folded suspensions are proposed to achieve improve RF characteristics. The simulation results at 35-60 GHz show an isolation of 10-16 dB for single beam and 20-36 dB for double beam switch. Insertion and return losses in up-state position for double switch were less than −0.1 dB and better than −24 dB, respectively. Due to the low effective spring constant of the serpentine folded suspensions and two actuation areas only 8.2 V of pull-down voltage is required. The mechanical characteristics of the RF MEMS switch including displacement, switching time, and Von Mises stress are studied.

Keywords:

RF MEMS switch , actuation voltage , isolation , meander beams , transmission line.