Variation risk analysis: MEMS fabrication tolerance for a micro CMM probe

  • Yunfei SunEmail author
  • Clifford R. Fowkes
  • Nabil Gindy
  • Richard K. Leach


This paper describes a methodology of variation risk analysis for microsystems using analytical modelling and simulation, a key characteristic (KC) method and statistical analysis considering MEMS fabrication tolerances. This methodology is applied to an innovative design for a micro co-ordinate measuring machine (CMM) probe utilising piezoelectric actuation and sensing currently being developed at the National Physical Laboratory. Analytical modelling is used to investigate the individual effects of dimensional parameters on the sensors’ open-circuit voltage output, which is a KC of the micro CMM probe. A computer simulation is performed using the finite-element method and compared with the analytical model. The KC variation is predicted and the variation contribution of the probe manufacturing processes is presented. This KC is mainly influenced by the thickness of the piezoelectric layer associated with the composite sol gel deposition process. Variation risk analysis results can be used to implement a variation risk mitigation strategy.


Variation risk analysis MEMS fabrication tolerance Analytical modelling and simulation Key characteristics Statistical variation analysis Micro CMM probe 


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Copyright information

© Springer-Verlag London Limited 2009

Authors and Affiliations

  • Yunfei Sun
    • 1
    Email author
  • Clifford R. Fowkes
    • 2
  • Nabil Gindy
    • 1
  • Richard K. Leach
    • 3
  1. 1.School of Mechanical, Materials and Manufacturing EngineeringUniversity of NottinghamNottinghamUK
  2. 2.Integrated Products ManufacturingKnowledge Transfer NetworkLondonUK
  3. 3.National Physical LaboratoryLondonUK

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