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An accurate computation of electrical force is significant in analyzing the performance of microelectromechanical systems and nanoelectromechanical systems. Many analytical and empirical models are available for computing the forces, especially, for a single set of parallel plates. In general, these forces are computed based on the direct electric field between the overlapping areas of the plates and the fringing field effects. Most of the models, which are based on direct electric field effect, consider only the trivial cases of the fringing field effects. In this paper, we propose different models which are obtained from the numerical simulations. It is found to be useful in computing capacitance as well force in simple and complex configurations consisting of an array of beams and electrodes. For the given configurations, the analytical models are compared with the available models and numerical results. While the percentage error of the proposed model is found to be under 6% with respect to the numerical results, the error associated with the analytical model without the fringing field effects is $\sim 50$ %. The proposed model can be applied to the devices in which the fringing field effects are dominant. [ABSTRACT FROM PUBLISHER]

Micro-electromechanical systems (MEMS) devices contain various mechanical components to have mechanical movement of the MEMS structure, such as the microcantilever beam. In this work, we present the new design of a microcantilever beam based on the regular hexagon shape and the conventional microcantilever beam. Experimental, analytical, and numerical analyses have been carried out for both configurations. Silicon dioxide (SiO 2) based microcantilever beams are fabricated using wet bulk micromachining. The thickness and width of the beams are kept constant at 0. 96 μ m and 35 μ m , respectively. In contrast, the length of the beam varies based on the number of hexagonal unit cells used. Here, we considered single, double, triple, quadruple, and quintuple hexagonal microbeams for the analyses. The new designs are analyzed for natural frequency, maximum deflection, and Q-factor in the first transverse vibration mode and compared with the equivalent uniform rectangular beams. Due to reduced stiffness, the first mode natural frequency of hexagon beams is lower than the equivalent uniform beams. The static deflection analysis has been performed numerically by applying a normal load of 10 nN at a free end of the beams. The maximum deflection of quadruple and quintuple hexagonal beams is found 450% and 438%, respectively, higher than the uniform beams due to a reduction in stiffness. In addition, the quality factor has been obtained for various damping mechanisms in ambient conditions. From the results obtained, it is observed that the quality factor associated with drag force damping is more dominant over other damping mechanisms. The experimentally measured quality factor has been compared with semi-analytical boundary element methods (BEM) and finite element based method in ANSYS. The values were found to be of the same order of magnitude. Due to the higher flexibility and excellent damping characteristics, the proposed hexagonal microbeams have potential applications as MEMS devices. However, its length and number of arrays can be optimized to minimize the sagging of the beam to the bottom substrate at the end. After analyzing the influence of pressure on structures consisting of hexagon beams and square membrane experimentally and numerically, we investigated the potential application of the suggested hexagonal beams as suspension springs in in-plane as well as out-of-plane MEMS accelerometers across different widths of the microbeams. [Display omitted] • Feasibility of fabricating different units of a hexagonal beam and its arrays are analyzed. • Frequency reduces and flexibility increases by around 75% using hexagonal beams. • Frequency change of around 50% can be obtained using inverse hexagonal shape. • Quality factor change of around 70% is found using inverse hexagonal shape. • Arrays of hexagonal units give near similar results as that of uniform beam of same length. [ABSTRACT FROM AUTHOR]