Authors: P.M. Nieva
Affilation: University of Waterloo, Canada
Pages: 5 - 8
Keywords: MEMS, sensors, harsh environment
Micro Electro Mechanical Systems (MEMS) for harsh environment applications are becoming increasingly important. They are recognized as essential for reducing weight and volume in strategic market sectors such as automotive, aerospace, turbomachinery, oil well/logging equipment, industrial process control, nuclear power and communications. For example, typical temperatures for automotive and aerospace systems range from 200∞C to 600∞C. Higher temperatures up to and above 900∞C can be found in extremely harsh environments, such as gas turbine engines, nuclear power generators, etc. The use of silicon (Si) has enabled the development of a broad range of MEMS sensor systems. However, when the environment temperature is too high (>250∞C), the electronics must reside in cooler areas, either remotely located or actively cooled. The additional components in the form of longer wires, more connectors, and/or bulky and expensive cooling systems, add undesired size and weight to the system. In general, optical signal detection has major advantages for safe signal transmission in high temperature environments. It can also be effectively integrated into Fabry-Perot (FP) microcavity-based sensors which can be readily manufactured using MEMS technology to form Micro-Opto Electro Mechanical Systems (MOEMS). In this paper, MEMS sensors for harsh environments are reviewed and the application of Fabry-Perot structures to a new MOEMS displacement sensor is studied. Simulations and experimental results are presented to show the sensitivity and accuracy of the sensors.