In this paper a coupled numerical and experimental approach to analyze the mechanical behaviour of series resistive RF M.E.M.Switches produced by Microsystems Division of ITC-irst is demonstrated. The switch consists in a thin gold-chromium membrane suspended on both an interrupted RF line and a pad. In the narrow central part two wings realize the contact with the dimples placed at the end of the underpass line when a difference of potential is applied between the pad and the bridge, generating an electrostatic force that pulls down the structure. The problem of reliability, today, is the principal obstacle for a complete diffusion of these switches in several RF applications. The aim of this work is the study of the influence of the parameters (geometry, material elastic properties, residual stress, physics conditions of the fluid that surrounds the bridge) on the MEMS dynamic. A Finite Element Model has been developed to characterize the mechanical behaviour of the system, with a particular focus to the fluid–structure interactions that strongly affect the motion of the switch. A experimental laser doppler vibrometry based technique has been applied in order to validate the model. Keywords: RF Switch, Dynamic Characterization, Finite Element Modelling, Laser Doppler Microvibrometry.
Dynamic Characterization of Series RF MEMS Switches
Margesin, Benno;Giacomozzi, Flavio
2006-01-01
Abstract
In this paper a coupled numerical and experimental approach to analyze the mechanical behaviour of series resistive RF M.E.M.Switches produced by Microsystems Division of ITC-irst is demonstrated. The switch consists in a thin gold-chromium membrane suspended on both an interrupted RF line and a pad. In the narrow central part two wings realize the contact with the dimples placed at the end of the underpass line when a difference of potential is applied between the pad and the bridge, generating an electrostatic force that pulls down the structure. The problem of reliability, today, is the principal obstacle for a complete diffusion of these switches in several RF applications. The aim of this work is the study of the influence of the parameters (geometry, material elastic properties, residual stress, physics conditions of the fluid that surrounds the bridge) on the MEMS dynamic. A Finite Element Model has been developed to characterize the mechanical behaviour of the system, with a particular focus to the fluid–structure interactions that strongly affect the motion of the switch. A experimental laser doppler vibrometry based technique has been applied in order to validate the model. Keywords: RF Switch, Dynamic Characterization, Finite Element Modelling, Laser Doppler Microvibrometry.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
