Design and simulation of a piezoelectric transducer by finite element

Abstract

One of the problems encountered in the manufacture of microstructures (MEMS) is the presence of residual stress caused by high temperatures during the manufacturing process. Residual stress generates deformation (ε) in materials, which consists of fractional changes in their dimensions (linear, surface or volume). The application of amorphous materials in the manufacture of MEMS is carried out at a lower temperature than those used with Polysilicon, so it is an alternative to reduce residual stress. The objective of the work is to analyze the mechanical behavior of thin films of amorphous Silicon germanium (a-SiGe). The analysis is carried out through the behavior of springboard type resonant structures and using the simulation of the finite element method (FEM). The resonance frequency of a trampoline-type structure depends only on its geometric dimensions, its density, and its Young's modulus. The simulation results show that the behavior of the resonance frequency and the Young's Modulus of thin films of a-SiGe, placed on a trampoline-type structure changes linearly whit Germanium content.