Abstract—In this survey paper, we describe and contrast three different approaches for extending circuit simulation to include micromachined devices. The most commonly used method, that of using physical insight to develop parameterized macromodels, is presented first. The issues associated with fitting the parameters to simulation data while incorporating design attribute dependencies are considered. The numerical model order reduction approach to macromodeling is presented second, and some of the issues associated with fast solvers and model reduction are summarized. Lastly, we describe the recently developed circuit-based approach for simulating micromachined devices, and describe the design hierarchy and the use of a catalog of parts. Index Terms—Extraction, macromodeling, MEMS, micromachining, microsystems, model-order reduction, simulation.

In this paper, we present a new technique by combining the Taylor series expansion with the Arnoldi method to automatically develop reduced-order models for coupled energy domain nonlinear microelectromechanical devices. An electrostatically actuated fixed-fixed beam structure with squeeze-film damping effect is examined to illustrate the model-order reduction method. Simulation results show that the reduced-order nonlinear models can accurately capture the device dynamic behavior over a much larger range of device deformation than the conventional linearized model. Compared with the fully meshed finite-difference method, the model reduction method provides accurate models using orders of magnitude less computation. The reduced MEMS device models are represented by a small number of differential and algebraic equations and thus can be conveniently inserted into a circuit simulator for fast and efficient system-level simulation.

The long term impact of MEMS technology will be in its ability to integrate novel sensing and actuation functionality on traditional computing and communication devices enabling the ubiquitous digital computer to interact with the world around it. The design and verification of such integrated systems will occur at the system level, driven primarily by the application. Application-driven system-level design methodologies that ease the integration of the digital domain to the real world using mixed domain technologies are therefore needed. A hierarchical structured approach that is compatible with standard IC design is outlined. It starts with schematic capture of a design topology, followed by behavioral simulation, layout generation, parasitic extraction, and final verification.

The use of MEMs technology has enabled the fabrication of micro-optical and micro-electro-mechanical systems on a common substrate. This has led to new challenges in computer aided design of optical micro-electro-mechanical systems. We have extended our opto-electronic system CAD tool, Chatoyant, to attempt to meet the needs of optical MEMS designers. This paper presents new component models and analysis techniques which extend our tool to support optical MEMS design. We demonstrate these extensions with the analysis of a micro-optical high speed FFT engine and a 1x2 optical MEM interferometer switch. Keywords: MEMS-CAD, optical MEMS, MOEMS, micro-optics 1. INTRODUCTION Applications for optical MEMS (micro-electrical-mechanical systems) are growing to include scanning, projection, display, switching, printing, sensing, modulating, and data storage. 24 As these applications are quickly evolving from abstract ideas to marketable products, it is essential to have CAD tools to model t...

Abstract. This paper describes a computationally efficient method to simulate mixed-domain systems under the requirements of a system-level framework. The approach is the combined use of Modified Nodal Analysis (MNA) for the representation of a mixed-technology device and piecewise linear (PWL) techniques to overcome the costly numerical evaluation found in conventional circuit or device simulators. This approach makes the simulation computationally fast, as well as more stable when compared with traditional circuit simulation. The PWL solver, based in the frequency domain, is more robust to inconsistencies in initial conditions and impulse changes when compared to integration based solvers in the time domain. The advantage of this method is that the same solver enables the integration of multi-domain devices (e.g., electrical, optical, and mechanical) in the same simulation framework. The use of this technique for the simulation of multi-domain systems has proven to give better performance in simulation time when compared to traditional circuit simulators with a relatively small decrease in the level of accuracy. Comparisons with traditional solvers, such as SPICE, show two to three orders of magnitude speedup with less than 5 % relative error. The ability to adjust the level of accuracy, either by varying the sampling rate or the number of regions of operation in the models, allows for both computationally fast and in-depth analysis in the same CAD framework. Key Words: MEM simulation, modified nodal analysis (MNA), optical MEM CAD tool, piecewise linear simulation (PWL), optoelectronic simulation, microsystem modeling and simulation 1.

The use of MEMs technology has enabled the fabrication of micro-optical and micro-electro-mechanical systems on a common substrate. This has led to new challenges in computer aided design of optical micro-electro-mechanical systems. We have extended our opto-electronic system CAD tool, Chatoyant, to attempt to meet the needs of optical MEMS designers. This paper presents new component models and analysis techniques which extend our tool to support optical MEMS design. We demonstrate these extensions with the analysis of a micro-optical high speed FFT engine and a 1x2 optical MEM interferometer switch. Keywords: MEMS-CAD, optical MEMS, MOEMS, micro-optics 1.

I thank my advisor Dr. Tamal Mukherjee for his constant guidance and encouragement. I am also thankful to Prof. Gary Fedder for his useful suggestions in a number of aspects of the work. I thank Steve Eagle for releasing the fabricated devices, Hasnain Lakdawala for help with the measurements and all the other students in the MEMS research group for stimulating discussions from time to time. elsewhere. I also acknowledge the invaluable support of my family and my friends in Pittsburgh and