Numerical modeling of 3-D comb drive electrostatic accelerometers structure (method of levitation force reduction)

Purpose – The purpose of this paper is to discuss the numerical modelling of 3D structure of micro-electro-mechanical systems (MEMS) accelerometers. The general idea being discussed is the method of levitation force reduction, as the main source of incorrect mathematical model of comb drive structure. Design/methodology/approach – Accelerometers design is a highly interdisciplinary area and, therefore, different methods and tools have to be exploited. Dynamic accelerometer behaviour modelling has been performed by use of a new object-oriented model (NOOM), based on complex computer field and mechanical models. Findings – The paper describes methods of levitation force reduction in electrostatic comb drive structures based on electrostatic structural models and finite elements method. Research limitations/implications – In the present work, the authors limit themselves to the electrostatic energy domains. Practical implications – Both, mechanical and electric models of accelerometers give the input data for defining the object-oriented model, based on Matlab-Simulink platform, fulfilling the general demand of dynamic behaviour simulation of comb drive structure. The proposed by authors methodology could give valuable contribution to MEMS design methodology. Originality/value – A new methodology has been successfully applied to calculation of levitation force in different geometries of comb drive. This methodology could be useful for multidisciplinary MEMS systems.