Practical pressure measurement using MEMS

Early pressure measuring equipment relied on a mechanism to translate the deflection of a structure into the motion of a pointer against a dial. Examples of this are the aneroid barometer and the Bourdon tube pressure gauge. However, with the move towards automated monitoring and control the requirement arose for pressure transducers with an electrical output. Initially this requirement was satisfied by the addition of an electrical position transducer to the mechanical structure, resulting in a complex and expensive assembly. Silicon MEMS is an ideal technology for pressure measurement because the same silicon element performs the two functions of a linear, repeatable mechanical structure and also an electronic strain gauge transducer. Combined with the low production cost afforded by wafer scale manufacture silicon MEMS has developed over the last 30 years to be the technology of choice for pressure measurement.