AVS 51st International Symposium
    Surface Science Tuesday Sessions
       Session SS2-TuM

Paper SS2-TuM5
Chemical Engineering of GaAs Surfaces with Aromatic Self-Assembled Monolayers

Tuesday, November 16, 2004, 9:40 am, Room 210C

Session: Self Assembled Monolayers
Presenter: M. Zharnikov, Universität Heidelberg, Germany
Authors: M. Zharnikov, Universität Heidelberg, Germany
A. Shaporenko, Universität Heidelberg, Germany
K. Adlkofer, Technische Universität München, Germany
A. Ulman, Polytechnic University
M. Tanaka, Technische Universität München, Germany
M. Grunze, Universität Heidelberg, Germany
Correspondent: Click to Email
Stochiometric GaAs (100) surfaces were functionalized with monolayers of non-substituted and substituted thiol-derived aromatic compounds and the engineered surfaces were studied by several complementary experimental techniques including synchrotron-based high resolution x-ray photoelectron spectroscopy and near edge x-ray absorption fine structure spectroscopy. The aromatic molecules were found to form well ordered and densely packed self-assembled monolayer on these substrates. The attachment to the substrate occurs over the thiolate headgroup while the intact aromatic chains have an upright orientation with an average tilt angle of about 30°. The functionalization of GaAs was found to prevent an oxidation and contamination of the substrate, keeping the GaAs surface in a pristine state. In addition, the wetting properties of this surface could be controlled by the selection of a suitable substitution, e.g. methyl or hydroxy group. The surface engineering of GaAs with functionalized aromatic monolayers can provide a crucial link for combining GaAs-based heterostructures and devices with bio-organic molecular assemblies.