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Microsystem Technologies

, Volume 16, Issue 8–9, pp 1665–1671 | Cite as

RMS voltage sensor based on a variable parallel-plate capacitor made of electroplated copper

  • Jan Dittmer
  • Lars Hecht
  • Rolf Judaschke
  • Stephanus Büttgenbach
Technical Paper

Abstract

We present an advanced RMS voltage sensor based on a variable parallel-plate capacitor using the principle of electrostatic force. The device is fabricated in a micromechanical surface process with a high-aspect ratio actuator, reinforced by copper electroplating employing a sacrificial photo-resist layer. Another copper layer with a coplanar waveguide below the actuator provides separated excitation and sensing electrodes. Flip-chip technology is employed for low-loss electrical connectivity. The presented design has a plate area of up to 3 × 3 mm2 and an initial gap distance of only 1.5 μm. We present results achieving a pull-in voltage below 1 V at frequencies from DC up to 1 GHz and sensitivities up to 1 fF/mV.

Keywords

Sacrificial Layer Coplanar Waveguide Stiff Actuator Surface Micromachining Process Copper Seed Layer 
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 research has been undertaken as a joined research project of the Institute of Microtechnology at the Technische-Universität Braunschweig and the High-Frequency Measuring Group of the Physikalisch-Technische Bundesanstalt (PTB).

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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Jan Dittmer
    • 1
    • 2
  • Lars Hecht
    • 1
  • Rolf Judaschke
    • 2
  • Stephanus Büttgenbach
    • 1
  1. 1.Institute for MicrotechnologyTechnische-Universität BraunschweigBraunschweigGermany
  2. 2.Physikalisch-Technische Bundesanstalt (PTB)BraunschweigGermany

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