M.Sc Thesis

M.Sc StudentLeus Vitaly
SubjectModeling the Static and Dynamic Responses of Electrostatic
MEMS Switches
DepartmentDepartment of Mechanical Engineering
Supervisor PROF. David Elata


In recent years, Micro-Electro-Mechanical Systems (MEMS) technology has grown rapidly, and has been implemented in many commercial applications. One of the emerging fields is Radio Frequency MEMS (RF-MEMS).

Electrostatic RF-MEMS switches are superior to current IC switches in terms of power consumption, high isolation, and low loss.

Though much progress has been made in the electro-magnetic performance of RF-MEMS switches, there are still many electromechanical issues that limit their functionality and reliability. Novel efficient modeling tools are needed to improve the design process of these components.

The present study focuses on modeling the dynamic electromechanical response of electrostatic switches. Common modeling approaches are often based on analysis of the static response. However, operation of RF-MEMS switches is essentially a dynamic transition between two states. The new modeling approach presented in this work is based on energy methods, and facilitates the prediction of the dynamic response while only considering static states of the system. This enables to avoid time integration of the momentum equations and provides an efficient method for estimating the dynamic pull-in parameters.

Analytic expressions of important response measures are derived for simple model problems. These analytic expressions are also applicable for actual switches with more general geometry, and they can be used as design rules.

The efficient modeling schemes are implemented in finite elements using ANSYS. The extremely high efficiency and accuracy of the implemented algorithms is demonstrated analyzing the 3D model of the typical RF-MEMS switch.