AVS 46th International Symposium
    Organic Electronic Materials Topical Conference Tuesday Sessions
       Session OE+EM+AS-TuA

Paper OE+EM+AS-TuA7
Self-Assembled Monolayers on Indium Tin Oxide

Tuesday, October 26, 1999, 4:00 pm, Room 616/617

Session: Organic Thin Film Growth
Presenter: A. Gölzhäuser, Universität Heidelberg, Germany
Authors: C. Yan, Universität Heidelberg, Germany
M. Zharnikov, Universität Heidelberg, Germany
A. Gölzhäuser, Universität Heidelberg, Germany
M. Grunze, Universität Heidelberg, Germany
Correspondent: Click to Email
Self-Assembled Monolayers (SAMs) of functionalized alkanethiols X(CH@sub 2@)@sub n@SH (X=CH@sub 3@, COOH) and carboxylic acid CH@sub 3@(CH@sub 2@)@sub n@COOH were prepared on indium tin oxide (ITO) surfaces and have been characterized by X-ray photoelectron (XPS) and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopies as well as by Atomic Force Microscopy (AFM). Thiols as well as carboxylic acids form homogeneous, ordered films on ITO. NEXAFS data suggest that the films are molecularly oriented with average alkyl chain tilt angles between ~34° for thiolate and ~31° for bifunctional SH(CH@sub 2@)@sub 15@COOH. From coadsorption experiments we find that on ITO the COOH group adsorbs preferentially over the SH group. AFM and LFM images indicate a smoothing of the relatively rough ITO surface by the adsorbed films. These results suggest that ITO surfaces can be passivated with Self-assembled monolayers and that SAMs can be utilized to covalently attach specific chemical functionalities to ITO electrodes.