LIGA uses deep X-ray lithography with synchrotron radiation for the production of high aspect ratio polymer microstructures. By shadow printing an X-ray mask is copied into an X-ray sensitive resist. A chemical developer dissolves the irradiated areas. Free lateral shape, structures heights from 20 µm up to several millimetres, vertical sidewalls with optical quality (Ra < 20 nm) and sub µm structure details are the basic characteristics of this process step.
The microstructure laboratory at ANKA consists of three beamlines for deep x-ray lithography, each dedicated to a specific task in the LIGA-process. In this chapter we present the LIGA3 beamline, dedicated to ultra deep X-ray lithography (UDXRL). The typical data for the structural height ranges from 400 to 2000 microns.