The Design And Simulation Of RF MEMS Switches

RF MEMS switches offer a substantially higher performance than p-i-n or field-effect transistor diode switches. RF MEMS application areas are in phase arrays and configusable apertures for defense and telecommunication systems, switching networks for satellite communication, and single-pole N -throw switches for wireless applications.The design and simulation of the RF MEMS switches with low pull-down voltages are the main content of this thesis. We design the contact RF MEMS switches. We first put forward a structure of the contact RF MEMS switches and create the model. Then we perform the electrostatic analysis with different parameters and design the contact RF MEMS switches with pull-down voltages as low as 9V.We design the capacitive RF MEMS switches with the pull-down voltages of 7V. We first put forward six kinds of film switches with different structures and calculate the effective stiffness constant and pull-down voltages. Then we perform the electrostatic analysis and modal simulation, concluding the switches with four connecting beams are comparatively ideal. Finally, we further change the structure of the switches with four connecting beams and perform the electrostatic analysis with different voltages and modal simulation, designing capacitive RF MEMS switches with low pull-down voltages.We estimate the damping force of the RF MEMS switches following the fundamental of the gas motion and Newtonian's mechanics. The results show that the damping force is much smaller than the electrostatic force and thus can be neglected.