Microsystem Technologies

, Volume 14, Issue 9–11, pp 1709–1714 | Cite as

Stiction issues and actuation of RF LIGA-MEMS variable capacitors

  • Darcy T. Haluzan
  • David M. Klymyshyn
  • Martin Börner
  • Sven Achenbach
  • Garth Wells
  • Timo Mappes
  • Jürgen Mohr
Technical Paper

Abstract

High aspect ratio variable capacitors have been fabricated using deep X-ray lithography and electroplating. Stiction phenomena applicable to high aspect ratio devices are presented, including the conditions for stiction to occur and the critical dimensions of structures. Actuation tests at 3 GHz are also presented and show a maximum capacitance of 0.86 pF with no actuation voltage and a minimum capacitance of 0.70 pF with an actuation voltage of 20 V just before pull-in, which gives a tuning range of 1.23:1. Corresponding Q-factor values are 49.3 and 70.8 respectively. After pull-in, the measured capacitance is 0.61 pF, corresponding to a tuning range of 1.41:1, with a maximum Q-factor of 102.9.

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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Darcy T. Haluzan
    • 1
    • 3
  • David M. Klymyshyn
    • 1
    • 3
  • Martin Börner
    • 2
  • Sven Achenbach
    • 1
    • 2
    • 3
  • Garth Wells
    • 1
  • Timo Mappes
    • 4
  • Jürgen Mohr
    • 2
  1. 1.Department of Electrical and Computer EngineeringUniversity of SaskatchewanSaskatoonCanada
  2. 2.Institut für Mikrostrukturtechnik (IMT)Forschungszentrum KarlsruheKarlsruheGermany
  3. 3.TRLabsSaskatoonCanada
  4. 4.Institut für Mikrostrukturtechnik (IMT)Universität KarlsruheKarlsruheGermany

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