0026-2714/$ - see front matter Ó 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.microrel.2005.07.095 Microelectronics Reliability 45 (2005) 1790–1793 www.elsevier.com/locate/microrel Thermal and electrostatic reliability characterization in RF MEMS switches Q.-H. Duong a, b, , L. Buchaillot a , D. Collard a , P. Schmitt c , X. Lafontan c , P. Pons d , F. Flourens d , F. Pressecq b a IEMN, ISEN Dpt , UMR CNRS 8520, Cité Scientifique, Av. H. Poincaré, BP60069, 59652 Villeneuve d’Ascq, FRANCE b CNES, 18 av. E. Belin, 31401 Toulouse, FRANCE c NOVAMEMS, 14 quai du 19 mars 1962, 09700 Saverdun, FRANCE d LAAS, 7 av. Col. Roche 31077 Toulouse, FRANCE Abstract The reliability of RF MEMS switches is closely linked to their operational and environmental conditions. This paper examines the reliability of five different capacitive switch designs by a combined use of modeling and experimental tools. Three-dimensional multiphysics finite element analysis was performed to estimate the actuation voltage and deflection vs. temperature variations of the micro-switches. The effect of temperature and temperature cycles on switch dilatation and pull-in voltage are studied, as well as the influence of different operational signals on switch reliability. Corresponding author. quynh-huong.duong@isen.iemn.univ-lille1.fr Tel: +33 (0) 5612 83559; Fax: +33 (0) 5612 74732 1. Introduction RF MEMS switches have demonstrated useful performance due to their low insertion loss and high isolation. Many universities and companies have developed RF MEMS switches in the last decade. Most of these switches rely on electrostatic actuation because of the low power consumption. Despite of these advantages, one important failure mechanism in electrostatic capacitive MEMS switches linked to operational conditions is dielectric charging. It causes stiction between the bridge and the dielectric layer covering the bottom electrode [1,2]. This charge build-up is closely related to the actuation voltage. And the actuation voltage amplitude is usually correlated with the device geometry, the stiffness and the residual stress state. Electromechanical modeling and experimentation are essential to improve performance of these devices [3]. Beside the operational conditions, RF MEMS switches used in space applications, have to work under harsh environmental conditions (low and high operational temperature, thermal cycles, vacuum, and shocks during launch …). One of the obstacles in the application of these devices in space is their reliability at different temperatures and when they are submitted to big temperature variations. Therefore, different switch designs able to compensate thermal dilatation and to develop reliability in temperature of RF MEMS switches were investigated in this article. Ó 2005 Elsevier Ltd. All rights reserved.