An analytical capacitance modeling of step structured perforated RF MEMS switch

In this paper, we have developed an analytical model for capacitance measurement of step structure perforated RF MEMS Switch. Capacitance model plays an important role to design and fabricate a high-performance of RF MEMS switches. Modelling signifies the validation of the proposed switch to design before fabrication by comparing the analytical and simulated results. Here, an analytical capacitance model for step structure perforated RF MEMS Switch is proposed based on ligament efficiency. The total capacitance of the switch is formulated with the parallel-plate capacitance developed by the total surface area of the electrodes and fringing field capacitance developed by sidewalls of the beam edges and perforations. The percentage of error is calculated to analyse the accuracy of the proposed model. The proposed capacitance model is verified by varying the switch design parameters such as dielectric thickness, the gap between electrodes, beam thickness and ligament efficiency. The percentage of error by the proposed model is compared with the two benchmark models and the obtained results shows good agreement than the benchmark models.