Microsystem Technologies

, Volume 14, Issue 9–11, pp 1715–1719 | Cite as

Submicron-scale surface acoustic wave resonators fabricated by high aspect ratio X-ray lithography and aluminum lift-off

  • Sven Achenbach
  • David Klymyshyn
  • Timo Mappes
  • Anton Kachayev
  • Venkat Subramanian
  • Garth Wells
  • Jürgen Mohr
Technical Paper

Abstract

A submicron-scale surface acoustic wave (SAW) resonator fabricated by high-aspect-ratio X-ray lithography (XRL) and metal lift-off that operates at microwave frequencies is presented. We demonstrate that XRL is especially well suited for SAW device templating, as long submicron-scale interdigitated transducer structures can be batch patterned with excellent structure quality. 0.4–2.0 μm thick PMMA layers were structured by X-ray lithography shadow projection using silicon nitride-based X-ray masks. Structures with a critical lateral feature size of down to 200–700 nm were processed. The polymer structures served as templates in a subsequent aluminum lift-off process. The metal electrodes were successfully tested as SAW resonators for high frequency applications, e.g. around 1.3 GHz, using calibrated 1-port RF wafer probing measurements. Compared with standard fabrication techniques, the high structure quality of submicron-scale polymer templates made of unusually thick PMMA layers offers additional possibilities to fabricate thicker metal transducers.

References

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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Sven Achenbach
    • 1
    • 2
    • 3
  • David Klymyshyn
    • 1
    • 3
  • Timo Mappes
    • 4
  • Anton Kachayev
    • 5
    • 3
  • Venkat Subramanian
    • 1
  • Garth Wells
    • 1
  • 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
  5. 5.Vecima NetworksSaskatoonCanada

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