AVS 50th International Symposium
    Processing at the Nanoscale Thursday Sessions
       Session PN-ThA

Paper PN-ThA10
Imaging of Monomolecular Lithographic Patterns by X-ray Photoelectron Spectromicroscopy and X-ray Absorption Spectromicroscopy

Thursday, November 6, 2003, 5:00 pm, Room 317

Session: Molecular Monolayers
Presenter: M. Zharnikov, Universität Heidelberg, Germany
Authors: M. Zharnikov, Universität Heidelberg, Germany
R. Klauser, National Synchrotron Radiation Research Center, Taiwan
A. Paul, Universität Heidelberg, Germany
A. Gölzhäuser, Universität Heidelberg, Germany
A. Scholl, Lawrence Berkeley National Laboratory
Correspondent: Click to Email
The development of novel approaches for the fabrication of nanostructures and, in particular, chemical and biological patterns is an important technological and scientific issue. One of perspective methods applies electron-beam patterning of chemisorbed monomolecular films (so-called self-assembled monolayers - SAMs), with the major advantage to tailor the resist properties through the exact architecture and packing of the molecular constituents. We have utilized scanning soft X-ray photoelectron and X-ray absorption spectromicroscopy to image and characterize different electron-beam patterned SAMs on gold substrates. Both techniques rely on characteristic spectroscopic features, which makes them chemically sensitive. The XPM measurements have been performed with a scanned zone-plate-focused X-ray beam and a 16 channels photoelectron spectrometer while the XAM images were collected with a X-ray PEEM working in a total electron yield (TEY) acquisition mode. The lateral structures in all SAM-based patterns could be clearly distinguished by both XPM and XAM. Chemical and physical changes in some of the resists could be directly monitored. The strength and limits of XPM and XAM to image monomolecular lithographic patterns are discussed. The major constrains of XPM are a strong inelastic background at the position of characteristic emissions and a rather limited (at present) lateral resolution. The major constrain of XAM is a rather poor surface sensitivity due to a large probing depth in the TEY acquisition mode. Ways to overcome the experimental constrains are considered, along with the issue of X-ray damage, which might be relevant at an X-ray exposure required for the acquisition of high-quality XPM and XAM images.