A Design Method for Electret MEMS Devices using Electrical Circuit Simulator

Abstract

In this paper, we propose a novel method to simulate the behavior of the energy harvester based on the permanent electret by using mechano-electrical equivalent circuits on an electrical circuit simulator. The electric field distributions made by the electret trapped in the electrical insulator are considered to build the electrostatic force by using the principle of virtual work. Electrostatically induced charge on the electrodes is also included in the model to handle the mechano-electric coupling between the electret device and the peripheral circuits. The developed equivalent circuit is implemented on the circuit simulator, and crosschecked against the experimental results in terms of the built-in electret potential. The behavior as an energy harvester is also studied to numerically present the output power as a function of the load resistance.