Parallel averaging for thermal noise mitigation in MEMS electrothermal displacement sensors

Ali Mohammadi, Seyed O Reza Moheimani, Mehmet Yuce

Research output: Contribution to journalArticleResearchpeer-review

5 Citations (Scopus)


The sensitivity of an electrothermal displacement sensor increases with its temperature, whereas a higher temperature range leads to higher thermal noise level, which imposes a tradeoff on the sensor's achievable resolution. We have developed a multiple sensor displacement measurement technique on a 1-degree-of-freedom silicon-on-insulator microelectromechanical systems nanopositioner that mitigates the mentioned tradeoff. To obtain maximum improvement, it is necessary to supply equal power to all of the sensors to ensure equal sensitivity. By combining three identical sensors, we have successfully achieved a 4-dB improvement in signal-to-noise ratio, which is in a good agreement with the averaging theory. Experiments show that the displacement resolution is improved from 0.3 to 0.15 nm/(Hz) in the prototype nanopositioner. Furthermore, improvement is possible by increasing the number of sensors around the stage. [2014-0120]

Original languageEnglish
Article number6954426
Pages (from-to)4-6
Number of pages3
JournalJournal of Microelectromechanical Systems
Issue number1
Publication statusPublished - 1 Feb 2015


  • averaging
  • Electrothermal sensor
  • microelectromechanical systems (MEMS)
  • nanopositioning
  • thermal noise

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