Microsystem Technologies

, Volume 15, Issue 5, pp 731–737 | Cite as

Analysis and design of a wide micro beam as a pressure gauge for high sensitivity MEMS fingerprint sensors

  • Mitra DamghanianEmail author
  • Burhanuddin Yeop Majlis
Technical Paper


Sensitivity improvement is a challenging issue in miniature pressure sensors. To improve sensitivity and linearity of the device, a wide micro beam structure has been proposed to gauge capacitance changes caused by the applied pressure in a capacitive MEMS fingerprint sensor. Bending behavior of the device and the effect of the protrusion geometry on partial loading of the micro beam has been analytically investigated. Based on the idea of efficient loading of the wide micro beam, an improved design for the capacitive fingerprint sensor is developed to increase sensitivity. It is shown with FEM simulations that the micro wide beam design is superior to the common membrane based MEMS fingerprint sensors in terms of sensitivity and linearity.


Wide Beam Free Edge Micro Electro Mechanical System Protrusion Material Membrane Shape 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work is financially supported by Malaysian Ministry of Science, Technology and Innovation under the project title “MEMS Devices and Sensing Microstructures”.


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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  1. 1.Institute of Microengineering and NanoelectronicsUniversiti Kebangsaan MalaysiaBangiMalaysia

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