Some investigations on electrostatic microbeam actuators for optical switching applications

Abstract

In the recent past, developments in the field of Micro Electro Mechanical Systems (MEMS) have seen many technological revolutions. The microsensors and microactuators have witnessed more advancement and posed many challenges. Due to the rapid growth of internet, data traffic has been enabled by optical telecommunication networks. Most of the MEMS switches are designed by trail and error method. MEMS structures are slightly modified after fabrication to meet the required characteristics. So a thorough understanding is required before fabrication, which is done through extensive simulations and analysis. Clamped-clamped beams, cantilever beams and fixed guided beams of length l ranging from 75µm to 100 µm, width from 1 µm to 15 µm and height of 2 µm are analyzed. Finite Element Method (FEM) has been used to model and analyze the beam characteristics. Eigen values and Eigen vectors are analyzed to get the mode shapes of the beams which give better understanding of the performance of the beams. Natural frequencies are estimated to find its suitability for optical switching applications. Simulations are carried out through Finite Element Software ANSYS. Further to optimize the parameters of the beams, genetic algorithms (GA), simulated annealing (SA) and hybrid GA-SA have been used which includes weight of the beams. The maximum displacement was estimated as 2.9390and#956;m and 3.3612and#956;m for fixed guided clamped and cantilever beam respectively. The natural frequencies have been estimated to vary between 0.102 MHz to 0.91635 MHz and 0.27524 MHz to 7.633MHz for fixed guided clamped beams and cantilever beams respectively. After examining the results obtained, it was clear that the maximum displacement varies with the dimensions of the beams and not with the materials used, but the pull-in voltage varies with materials of the beams as well as with the dimensions of the beams. newline newline newline