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Microsystem Technologies

, Volume 14, Issue 9–11, pp 1721–1725 | Cite as

Submicron polymer structures with X-ray lithography and hot embossing

  • Timo Mappes
  • Matthias Worgull
  • Mathias Heckele
  • Jürgen Mohr
Technical Paper

Abstract

This article describes the process chain for replication of submicron structures with varying aspect ratios (AR) up to 6 in polymethylmethacrylate (PMMA) by hot embossing to show the capability of the entire LIGA process to fabricate structures with these dimensions. Therefore a 4.7 μm thick layer of MicroChem 950k PMMA A11 resist was spin-coated on a 2.3 μm Ti/TiO x membrane. It was patterned with X-ray lithography at the electron storage ring ANKA (2.5 GeV and λ c ≈ 0.4 nm) at a dose of 4 kJ/cm3 using a Si3N4 membrane mask with 2 μm thick gold-absorbers. The samples were developed in GG/BDG and resulted in AR of 6–14. Subsequent nickel plating at 52°C resulted in a 200 μm thick nickel tool of 100 mm diameter, which was used to replicate slit-nozzles and columns in PMMA. Closely packed submicron cavities with AR 6 in the nickel shim were filled to 60% during hot embossing.

Keywords

PMMA Molding Temperature Residual Layer Packing Time Incomplete Filling 
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.

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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Timo Mappes
    • 1
  • Matthias Worgull
    • 2
  • Mathias Heckele
    • 2
  • Jürgen Mohr
    • 2
  1. 1.Institut für Mikrostrukturtechnik (IMT)Universität KarlsruheKarlsruheGermany
  2. 2.Institut für Mikrostrukturtechnik (IMT)Forschungszentrum Karlsruhe GmbHKarlsruheGermany

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