Analysis of magnetic latching mechanism in the application of bi-stable MEMS switches

A magnetic latching mechanism of single cantilever and cross torsion beam in the application of bi-stable MEMS switches is presented in this letter. The analytical results show the relationship between the magnetic force induced by the permanent magnet in the work gap and the elastic force of cantilever in the latching process. When the magnetic force is larger or the stiffness of the cantilever is smaller, the driving power consumption and the contact resistance will be smaller and the response will be faster. A cross torsion beam and a magnetic circuit are made up of the magnetic latching structure which has the capability of controlling the outer circuits. All of the components of the device are fabricated by UV-LIGA technology. The test results reveal the latching process with Nano indent tester and can be explained well with the conclusion.