Low Voltage Dual Beam Capacitive Switches For Reconfigurable Microsystems

In this work, the modeling and simulation of a temperature tolerant switch design with improved RF (Radio Frequency) performance is proposed. Simulations are done in HFSS (High Frequency Structure Simulator) and Coventor Ware. Switch is fabricated on a quartz substrate. The simulated value for pull-in voltage is obtained as 27.8 V. RF performance parameters for a switch include insertion loss, return loss and isolation. The concepts of impedance matching and inductive tuning of a temperature tolerant switch are investigated which shows an improvement in RF characteristics of switch in Ka band ie. return loss improved to -45 dB from -15 dB, and isolation improved to -65 dB from -55 dB . Impedance matching involves two switches separated by a high impedance transmission line of a specific length, which is optimized to 600 μm to get minimum return loss. It gives 0.45 μm beam deflection at 500 K.