Comparative Study on Modeling Approaches of V-Shaped MEMS Temperature Sensors

• Published in: IEEE transactions on instrumentation and measurement 2019-10, Vol.68 (10), p.3766-3775
• Main Authors: Cohen, Yaniv, Ya'akobovitz, Assaf
• Format: Article
• Language: English
• Subjects: Comparative studies; Deflection; Devices; Equations of motion; Finite element method; Iterative methods; Mathematical model; Microelectromechanical systems; Micromechanical devices; Performance evaluation; Reliability analysis; Residual stress; Signal to noise ratio; Stiffness; Substrates; Temperature dependence; Temperature sensors; Thermal expansion; thermal microelectromechanical system (MEMS); Tolerances; V-shaped MEMS devices
• ISSN: 0018-9456; 1557-9662
• DOI: 10.1109/TIM.2018.2879144

Thermal microelectromechanical system (MEMS) devices have gained immensely in popularity due to their good performances, relatively simple fabrication process, and to the availability of modeling tools. In this paper, the modeling results of several models were compared and the ability of each to reliably assess the performances of V-shaped thermal MEMS devices was investigated. The results of several models, in which the governing equations of motion were directly solved, were compared to those obtained from nonlinear large-deflection 3-D finite element analysis that was verified experimentally. The models were modified by including the temperature-dependent properties of the material of the device. In addition, a numerical iterative force control solution scheme was developed and used to predict the performances of V-shaped devices. Important parameters of V-shaped devices, such as apex deflection, stiffness, and output force, were evaluated in terms of the applied temperature and device geometry. In addition, the feasibility of capacitive sensing was demonstrated and high signal-to-noise ratio was calculated. Finally, the influence of microfabrication tolerances and internal stress on the performances of the devices were studied. Therefore, this paper will help future researchers and designers to assess the reliability of models of thermal MEMS devices and better evaluate device performance.