Simulation of plastic deformation of sculptured diaphragm silicon microstructure

Abstract

Single crystal silicon MEMS microstructures could be plastically deformed during high-temperature manufacturing process. In this paper, an iterative finite element simulation method based on Von Mises yield criterion is proposed to determine the plastic deformation of silicon microstructure. In the proposed method, the critical condition for plastic deformation is that the maximum Von Mises stress of the microstructure equals to the yield stress. Sculptured diaphragm microstructures with different dimensions are designed to verify the method. Plastic deformation of the structure is measured after the annealing process of 1100°C. The simulation value fits the experiment well and the average deviation between the simulation data and experimental data is 2.2%.