New insights into charging in capacitive RF MEMS switches

This paper discusses dielectric charging in electrostatic RF-MEMS switches. We show that more than one charging mechanism can be present and impacts their lifetime. These different mechanisms can cancel, mitigate or enhance each otherpsilas influence on the lifetime, depending on the materials used and on the test conditions. Contrarily to the common understanding of the dielectric charging, we show that charge trapping in the dielectric interposer is not always the dominant charging mechanism leading to the failure. We finally show that bipolar actuation is not a general remedy for charging in electrostatic RF MEMS switches.