Research On RF MEMS Switch Reliability

Due to its excellent isolation and insertion loss，good linearity, RF MEMS switchis having been widely used in wireless communication and phase control radar. Thereliability of RF MEMS switch is key to the industrialization, while, this article isgoing to research and analysis direct contact and capacitive switch reliability, whichproviding technical reserves for further development of RF MEMS.Based on the analyze of electromagnetic model and mechanical model of directcontact of the switch, the paper focuses on the influence of the reliability of contactswitch of contact resistance, power and other factors as well as analysis the influenceof variation of structure dimension to the MEMS switch pull-in voltage, switchingtime, recovery stress and contact stress by aids of the Intellisuite software. To thehigher driving voltage problem, this paper puts forward a method by changing thethickness of the Si3N Si3N4beam, lowing the driving voltage by reduction thebending angle. This method does not need to change the switch structure, whenreducing the driving voltage the switch contact force and restoring force decreased less,the switch performance only slightly decreased, and the simulation results show that itcan effectively improve the switch reliability.Then according to the analysis of the failure mechanism of the RF MEMS capacitiveswitch reliability, this article establishes and analyses a charging model on based of theMSEM data switch, and classifies the switch failure. Finally it gives the design of abending type capacitive RF switch to make low voltage drive, which effectiveness isshowed by C-V test.In this paper, the reliability of two kinds of switch the direct contact and capacitancetype is studied, and achieved initial progress. As the factors of influencing the RFMEMS reliability are in many aspects, the development of reliable RF MEMS switchneed to accumulate more research and technology.