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Microsystem Technologies

, Volume 19, Issue 3, pp 425–431 | Cite as

High aspect ratio metal micro and nano pillars for minimal footprint MEMS suspension

  • Felix GreinerEmail author
  • Helmut F. Schlaak
Technical Paper

Abstract

Vertical nano and micro pillars perpendicularly rising from a substrate offer two lateral translatory–rotatory degrees of freedom. Electroforming allows their production as small footprint integrated suspension elements of micro to nano scale. This paper demonstrates the design of a novel inertial sensor concept with acceleration sensor and gyroscope function using only one inertial mass. Experimental results using UV Direct LIGA with AZ 125 nXT show the feasibility of a technology demonstrator with a copper micro pillar of 400 μm length and 40 μm diameter. Further work using x-ray Direct LIGA is scheduled for the production of the pillar with a length of 100 μm and a diameter of 3–6 μm. Fabrication concepts and pilot tests show promising possibilities for miniaturization towards nano scale pillars for minimal footprint suspension in MEMS.

Keywords

Inertial Sensor Acceleration Sensor Through Silicon Vias Film Photoresist Movable Object 
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.

Notes

Acknowledgments

This work was supported in part by the German Federal Ministry of Education and Research (BMBF) under the grants 16SV5053. The X-ray lithography part of this work will be carried out with the support of the Karlsruhe Nano Micro Facility (KNMF 2010-004-000365, www.knmf.kit.edu), a Helmholtz Research Infrastructure at Karlsruhe Institute of Technology (KIT, www.kit.edu). The support of Technische Universität Darmstadt EMK clean room staff Bernhard Jochem and Darina Riemer is acknowledged. Valuable technical discussions with Wolfgang Ensinger, and Markus Rauber of TUD Material Science, Christina Trautmann of GSI Helmholtz Centre for Heavy Ion Research, Robert Preisser and Xihai Kang of Atotech are greatly appreciated.

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Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  1. 1.Microtechnology and Electromechanical Systems Laboratory (M+EMS), Institute of Electromechanical DesignTechnische Universität DarmstadtDarmstadtGermany

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