Microsystem Technologies

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

Submicron polymer structures with X-ray lithography and hot embossing

  • Timo MappesEmail author
  • Matthias Worgull
  • Mathias Heckele
  • Jürgen Mohr
Technical Paper


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.


PMMA Molding Temperature Residual Layer Packing Time Incomplete Filling 
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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Timo Mappes
    • 1
    Email author
  • 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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