Growth of self-assembled monolayers on sulfide treated gallium arsenide using predetermined linkage moieties

Article type: Research Article

Authors: Keys, Andrea | Barron, Andrew R.

Affiliations: Department of Chemistry, Department of Mechanical Engineering and Materials Science, and Richard E. Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005, USA

Note: [] Corresponding author. E-mail: [email protected]

Abstract: Hexanethiol (C6H13SH), phenylphosphonic acid [PhP(O)(OH)2], and 3-bromo-benzoic acid (3-BrC6H4CO2H) have been reacted with {100}-GaAs surface which have been pretreated with an acid etch and an ammonium sulfide reactive passivation layer. The chemically reacted surfaces have been characterized by XPS and advancing contact angle measurements. As predicted from simple model compounds, [(tBu)2Ga(µ-X)]2, the thiol and phosphonic acid ligands allow for uniform surface layers, while the carboxylic acid is geometrically unsuited to binding the surface of GaAs. The relative acidity of thiol versus phosphonic acid results in greater coverage for the latter due to a more facile reaction with the sulfide passivated GaAs surface.

Keywords: Gallium arsenide, Self-assembled monolayer, Thiol, Phosphonic acid, Benzoic acid, X-ray photoelectron spectroscopy

DOI: 10.1080/10241220600709671

Journal: Main Group Chemistry, vol. 4, no. 4, pp. 263-271, 2005