Modeling and Analysis of DC-contact RF MEMS Switch Considering Crosstalk between DC and RF Signals

This paper presents a lumped parameter model of the DC-contact RF MEMS switch considering DC and RF crosstalk in millimeter wave. The crosstalk is caused by the capacitor between the actuator and cantilever, and the overlap area between ground line of transmission line (TML) and bias line, which can result in a resonance at around 40 GHz. The model is verified using two kinds of different switches. To diminish the leakage of RF signal and decrease the area of the device, we suggest that the isolation resistor should be put under the ground line. With the help of modified lumped parameter model, the resistance and position of the isolation resistor are simulated and studied. The analysis shows that the isolation resistance under ground line should be higher than 10 k Ω, and the resistor needs to be as close to the actuator as possible, which is important for switch with low area consumption and high RF performance.