Analysis And Design Of Micro-switch Based On MEMS

MEMS switches based on metal-metal contact are useful in a variety of power management information processing and communication systems because their on resistance is lower than that of semiconductor switches and their off resistance and transmission frequency are higher than that of semiconductor switches.Typically,there are three kinds of different structures of micro-switch:cantilever beam,fixed-fixed beam (Air Bridge) and torsion beam,all of these are actuated by electrostatic force.The former two structures still have two different modes:series mode and bypass mode. Usually series mode is used in low frequency circuit while bypass mode is used in high frequency circuit,series mode micro-switch with cantilever structure is similar to an FET,when voltage is applied on gate,and the FET will be turned on between source and drain.This thesis gives an analysis of a kind of micro-switch with cantilever structure;Analyzes and calculates the defection of cantilever in detail;presents the fabrication process of micro-switch with cantilever beam;the performance of this thesis is as following:Chapter one:Outlined the MEMS technology and micro-switch. Analyzed different structures of micro-switch and presented the main task of this thesis.Chapter two:Analyzed deformation and calculated the deflection,internal forces,and touch force of uniform cantilever beam and non-uniform cantilever. And also calculated the basal frequency of these two kinds of cantilever beam. Analyzed the characters of this two-micro-switch with different structures at the end.Chapter three:Presents the fabrication process of micro-switch with cantilever beam and designed the masks.Chapter four:Designed circuit to actuate the micro-switch,analyzed the dynamic and static property of voltage doublers circuit. In the end,this chapter also described and analyzed the features of switched-capacitor DC-DC converter.Chapter five:Conclusion of this thesis.