Design and Simulation of RF MEMS Switched Parallel Plate Capacitors

In wireless communication systems, passive elements like tunable capacitors are needed in a variety of applications, such as Voltage Controlled Oscilla- tors (VCO), tunable matching networks and filters. In this books, the design and modeling of a Switched RF-MEMS parallel plate (air-gap) capacitor is presented. The feasibility of realizing switched RF MEMS capacitors in some technology constrains is considered with a targeted specifications given prior to design such as: low actuation voltage (< 3 Volts), capacitance ratio of 20, upstate capacitance of 20fF and electrical quality factor of 100. The design of low stiffness suspensions, to achieve the low actuation voltage, is discussed in detail.