Dielectric Charging Sensitivity on MEMS Switches

The paper presents the approach used to limit the dielectric charging on an ohmic electrostatic series switch developed by CEA-LETI. The first part focuses on the methodologies used for the dielectric charging identification, in particular, a test protocol based on holding tests is proposed and completes the common protocol based on sweeping tests. The primary results showed that the switch was highly sensitive to dielectric charging. A failure tree analysis applied to the switch identified primary root causes responsible for the dielectric charging: surface contamination on the lower face of the membrane, dielectric properties and in-situ environment. Process optimizations and favorable in-situ environment allowed reducing the dielectric charging.