Abstract

This paper presents two methods for counteracting the unwanted de flection due to warping or buckling e effects,which are serious potential problems in many fabrication processes f micro electromechanical (MEMS)structures due to thin film phenomena.This study is primarily suited for electrostatically actuated RF MEMS switches whose RF and DC performance can be signi ficantly deteri rated by out of plane warping.It can also be applied to MEMS acceler meters,resonators and other similar systems.The first technique of cuses on modifying the support structure and the spring constant of the switch,while the second in volves a more complicated fabrication pr cess, which selectively increases the switch thickness. Both these techniques yield switches with tw to ten times less warping under the same fabrication conditions.The second method,however, presents the additional advantage f maintaining the actuation voltage almost una effected.