A Numerical Study on Thermal Stress Analysis of A Micro Electro Mechanical Systems (Mems) Bimetallic Actuator

Abstract

Micro Electro Mechanical Systems (MEMS) actuators are capable of obtaining mechanical motion on a very small scale due to the design, materials and fabrication. A bi metallic micro actuator is also one of MEMS device that can perform physical functions at micron meter scale. A bi metallic micro actuator based on thermal sensing is capable of making small displacements due to resultant heating at the end. Because of different thermal expansion coefficients of the bonded strip materials, the actuator undergoes bending and the resultant deformation is a measure of the micro motion. During bending, the stresses generated may cause the beam to undergo staring or deformation. In the present work, MEMS actuator in which a bi metallic strip made up of Silicon dioxide and silicon layers bonded together is modeled and simulated using Finite Element Method for finding the total deformation, stresses and strain. The results are validated with theoretical results and are in good agreement.