Electromechanical Modeling and Simulation of RF MEMS Switches

The design of RF MEMS switches involves several disciplines: mechanics, materials science and electrical engineering. While significant progress has been made in the RF design of the switches, mechanical and material studies are required for mass commercialization of reliable devices. Senturia and co-workers at MIT have presented a closed form solution to describe the electromechanical behavior of a fixed-fixed switch. However, in some practical applications, multi-domain simulations are required to account for membrane shape, non-uniform state of residual stress, temperature and other effects. In this presentation, we will describe the modeling and simulation of MEMS switches and discuss their electromechanical performances. The switch, bottom electrode and surrounding air were all included and meshed in the model. Iterations between the electrostatic and structural analyses were performed until the solution converged. The developed method is applicable to all types of electrostatic switches, though the design of a capacitive coupling shunt switch has been examined.

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