Preliminary results at the ultradeep x-ray lithography beamline at CAMD

The Center for Advanced Micro structures and Devices (CAMD) at Louisiana State University supports one of the strongest programs in synchrotron radiation micro fabrication in the USA and, in particular, in deep x-ray lithography. Synchrotron radiation emitted form CAMD's bending magnets has photon energies in the range extending from the IR to approximately 20 keV. CAMD operates at 1.3 and 1.5 GeV, providing characteristic energies of 1.66 and 2.55 keV, respectively. CAMD bending magnets provide a relatively soft x-ray spectrum that limits the maximal structure height achievable within a reasonable exposure time to approximately 500 micrometers . In order to extend the x-ray spectrum to higher photon energies, a 5 pole 7T superconducting wiggler was inserted in one of the straight sections. A beam line and exposure station designed for ultra deep x-ray lithography was constructed and connected to the wiggler. First exposures into 1 mm and 2 mm thick PMMA resist using a graphite mask with 40 micrometers thick gold absorber has been completed.