Physics-aware macromodels for MEMS switches Aurel-Sorin Lup, Gabriela Ciuprina, Daniel Ioan and Anton Duca Department of Electrical Engineering, Politehnica University of Bucharest, Bucharest, Romania, and Alexandra Nicoloiu and Dan Vasilache IMT-Bucharest, Bucharest, Romania Abstract Purpose – The purpose of this paper is to propose a physics-aware algorithm to obtain radio frequency (RF)- reduced models of micro-electromechanical systems (MEMS) switches and show how, together with multiphysics macromodels, they can be realized as circuits that include both lumped and distributed parameters. Design/methodology/approach – The macromodels are extracted with a robust procedure from the solution of Maxwell’s equations with electromagnetic circuit element (ECE) boundary conditions. The reduced model is extracted from the simulations of three electromagnetic field problems, in full-wave regime, that correspond to three configurations: signal lines alone, switch in the up and down positions. Findings – The technique is exemplified for shunt switches, but it can be extended for lateral switches. Moreover, the algorithm is able take frequency dependence into account both for the signal lines and for the switch model. For the later, the order of the model is increased until a specified accuracy is achieved. Originality/value – The use of ECE as boundary conditions for the RF simulation of MEMS switches has the advantage that the definition of ports is unambiguous and robust as the ports are clearly defined. The extraction approach has the advantage that the simplified model keeps the basic phenomena, i.e. the propagation of the signal along the lines. As the macromodel is realized with a netlist that uses transmission lines models, the lines’ extension is natural. The frequency dependence can be included in the model, if needed. Keywords MEMS modeling, Computational electromagnetics, Multiphysics, Model order reduction, Equivalent circuit models Paper type Research paper 1. Introduction Requirements design of radio frequency (RF) micro-electromechanical systems (MEMS) switches refers to two main aspects. First, their transition from one stable state to the other, characterized by quantities such as the pull-in/out voltages and the commutation time; and second, their electrical characteristics such as the S parameters in the stable states i.e. insertion, isolation and reflection loss (Rebeiz, 2003; Jaafar et al., 2014). These devices, used in many MEMS, involve complex phenomena that make the models obtained from field analysis be too large to be included in system level simulations (Bechtold et al., 2013). That is why model order reduction strategies are needed, so that a discrete model with a reduced complexity is obtained (Schilders et al., 2008). The mathematically oriented reduction techniques are general but the reduced model obtained losses the physics inside and This paper forms part of a special section “12th International Conference on Scientific Computing in Electrical Engineering (SCEE 2018)”, guest edited by Vittorio Romano. The work has been funded by the Operational Programme Human Capital of the Ministry of European Funds through The Financial Agreement 51675/09.07.2019, SMIS code 125125. Macromodels for MEMS switches 497 Received 24 June 2019 Revised 4 October 2019 Accepted 10 December 2019 COMPEL - The international journal for computation and mathematics in electrical and electronic engineering Vol. 39 No. 2, 2020 pp. 497-509 © Emerald Publishing Limited 0332-1649 DOI 10.1108/COMPEL-06-2019-0267 The current issue and full text archive of this journal is available on Emerald Insight at: https://www.emerald.com/insight/0332-1649.htm