Articles techniques et présentations

The silicon diaphragm is one of the most common structures in Micro-Electromechanical Systems (MEMS). However, it is susceptible to creep deformation at elevated temperatures. This paper presents a transient finite element model which simulates the mechanical behavior of the micromachined silicon diaphragms at the temperature of 900 °C. The constitutive equations proposed by Alexander and Hassen are employed in COMSOL Multiphysics®. The results show that the larger the diaphragm radius, the larger the density of the moving dislocation is. There is good agreement between the model prediction and the experiment data for the diaphragms with a radius in the range of 1.5mm to 2mm.