Novel analytical model for optimizing the pull-in voltage in a flexured MEMS switch incorporating beam perforation effect

Abstract This paper presents a new method for the design, modelling and optimization of a uniform serpentine meander based MEMS shunt capacitive switch with perforation on upper beam. The new approach is proposed to improve the Pull-in Voltage performance in a MEMS switch. First a new analytical model of the Pull-in Voltage is proposed using the modified Mejis-Fokkema capacitance model taking care of the nonlinear electrostatic force, the fringing field effect due to beam thickness and etched holes on the beam simultaneously followed by the validation of same with the simulated results of benchmark full 3D FEM solver CoventorWare in a wide range of structural parameter variations. It shows a good agreement with the simulated results. Secondly, an optimization method is presented to determine the optimum configuration of switch for achieving minimum Pull-in voltage considering the proposed analytical mode as objective function. Some high performance Evolutionary Optimization Algorithms have been utilized to obtain the optimum dimensions with less computational cost and complexity. Upon comparing the applied algorithms between each other, the Dragonfly Algorithm is found to be most suitable in terms of minimum Pull-in voltage and higher convergence speed. Optimized values are validated against the simulated results of CoventorWare which shows a very satisfactory results with a small deviation of 0.223 V. In addition to these, the paper proposes, for the first time, a novel algorithmic approach for uniform arrangement of square holes in a given beam area of RF MEMS switch for perforation. The algorithm dynamically accommodates all the square holes within a given beam area such that the maximum space is utilized. This automated arrangement of perforation holes will further improve the computational complexity and design accuracy of the complex design of perforated MEMS switch.

[1]  H Shahraki,et al.  DESIGN AND SIMULATION OF AN RF MEMS SWITCH FOR REMOVING THE SELF-ACTUATION AND LATCHING PHENOMENA USING PSO METHOD , 2013 .

[2]  Mojgan Daneshmand,et al.  RF-MEMS switches with new beam geometries: improvement of yield and lowering of actuation voltage , 2007, SPIE Micro + Nano Materials, Devices, and Applications.

[3]  Jill C. Blecke Control design and genetic algorithm optimization for electrostatic MEMS , 2011 .

[4]  Xiuhan Li,et al.  Effect of etch holes on the capacitance and pull-in voltage in MEMS tunable capacitors , 2010 .

[5]  Anirban Bhattacharya,et al.  Analysis of the Pull-In Phenomenon in Microelectromechanical Varactors , 2012, 2012 25th International Conference on VLSI Design.

[6]  Andrew Lewis,et al.  The Whale Optimization Algorithm , 2016, Adv. Eng. Softw..

[7]  Roshdy AbdelRassoul,et al.  Analysis and Simulation of Serpentine Suspensions for MEMS Applications , 2013 .

[8]  Xiao-Feng Xie,et al.  DEPSO: hybrid particle swarm with differential evolution operator , 2003, SMC'03 Conference Proceedings. 2003 IEEE International Conference on Systems, Man and Cybernetics. Conference Theme - System Security and Assurance (Cat. No.03CH37483).

[9]  Zlatica Marinkovic,et al.  Artifical neural networks in RF MEMS switch modelling , 2016 .

[10]  John L. Volakis,et al.  Robust Design of RF-MEMS Cantilever Switches Using Contact Physics Modeling , 2009, IEEE Transactions on Industrial Electronics.

[11]  M. Ahmadi,et al.  Pull-in voltage study of electrostatically actuated fixed-fixed beams using a VLSI on-chip interconnect capacitance model , 2006, Journal of Microelectromechanical Systems.

[12]  A. Bendali,et al.  Holes Effects on RF MEMS Parallel Membranes Capacitors , 2006, 2006 Canadian Conference on Electrical and Computer Engineering.

[13]  Ashish Kumar Sharma,et al.  Investigation of actuation voltage for non-uniform serpentine flexure design of RF-MEMS switch , 2014 .

[14]  Cevher Ak,et al.  An Inversely Designed Model for Calculating Pull-In Limit and Position of Electrostatic Fixed-Fixed Beam Actuators , 2014 .

[15]  Gang Xu,et al.  Human Behavior-Based Particle Swarm Optimization , 2014, TheScientificWorldJournal.

[16]  K. A. Jose,et al.  RF MEMS and Their Applications , 2002 .

[17]  N. P. van der Meijs,et al.  VLSI circuit reconstruction from mask topology , 1984, Integr..

[18]  H. Wikle,et al.  The design, fabrication and evaluation of a MEMS PZT cantilever with an integrated Si proof mass for vibration energy harvesting , 2008 .

[19]  Gabriel M. Rebeiz RF MEMS: Theory, Design and Technology , 2003 .

[20]  Ghader Rezazadeh,et al.  Pull-In Voltage of Fixed-Fixed End Type MEMS Switches with Variative Electrostatic Area , 2006 .

[21]  James Kennedy,et al.  Particle swarm optimization , 2002, Proceedings of ICNN'95 - International Conference on Neural Networks.

[22]  Xinjie Yu,et al.  Introduction to evolutionary algorithms , 2010, The 40th International Conference on Computers & Indutrial Engineering.

[23]  Jacopo Iannacci Practical Guide to RF-MEMS , 2013 .

[24]  Igor L. Markov,et al.  VLSI Physical Design - From Graph Partitioning to Timing Closure , 2011 .

[25]  Singiresu S. Rao Engineering Optimization : Theory and Practice , 2010 .

[26]  Jugdutt Singh,et al.  Modelling and analysis of fringing and metal thickness effects in MEMS parallel plate capacitors , 2006, SPIE Micro + Nano Materials, Devices, and Applications.

[27]  Stephen D. Senturia,et al.  The effect of release-etch holes on the electromechanical behaviour of MEMS structures , 1997, Proceedings of International Solid State Sensors and Actuators Conference (Transducers '97).

[28]  Kalaiarasi Arcot Ramakrishnan,et al.  Closed form Models for Pull-In Voltage of Electrostatically Actuated Cantilever Beams and Comparative Analysis of Cantilevers and Microgripper , 2012 .