A novel structure for the capacitive micromachined switches with low actuation voltage is proposed. In this structure both contact plates of the switch are designed as displaceable membranes. Two structures with similar dimensions and conditions, differing on only the number of the displaceable beams are analytically investigated as well as simulated using ANSYS software. The obtained results indicate about 30% reduction in actuation voltage from the conventional single beam to our proposed double beam structure. The stress on the beam due to the actuation voltage is also reduced increasing the switching life time. The dynamic simulation results in switching time of 6.5 μsec compared to the 8.9 μsec of the analytical results. It can be implemented by the well established surface micromachining for RF applications.
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