Capacitance modelling of perforated RF MEMS shunt switch

This paper presents the capacitance modelling of RF MEMS shunt switch by using the parallel plate, fringing field, and parasitic capacitance. The model carried out fringing capacitance due to the etched holes and thickness of the beam. The analytical proposed modelling is evaluated in both up and downstate capacitance of the switch. The proposed switch simulation results are performed in the 3D simulator COMSOL multiphysics tool. The variation of capacitance analysis is evaluated by changing the dielectric thickness, air gap, and ligament efficiency (µ) are taken out and these analytical and simulation results are compared with benchmark models for evaluating capacitances in both up and downstate of the switch. The error percentage contribution of up and downstate is 1.61% and 0.57%, by comparing benchmark models, the proposed empirical model is obtained less percentage with ligament efficiency (µ) 0.7, dielectric thickness is 0.1 µm, and beam thickness is 0.5 µm.