Reliability of MEMS capacitive switches

Abstract

This paper reviews the progress over the past decade in improving the reliability of MEMS capacitive switches. The emphasis is on mitigating the dielectric-charging problem as it currently limits the lifetime of these switches. The most critical is to distinguish charging of the dielectric surface from that of the dielectric bulk, and then mitigate them separately. Once surface charging is eliminated and bulk charging is greatly reduced, the switch lifetime can be prolonged almost indefinitely by using an intelligent closed-loop CMOS control circuit. This will facilitate the use of MEMS capacitive switches in military and commercial systems.