AVS 47th International Symposium
    Surface Science Tuesday Sessions
       Session SS2+NS+BI+EL-TuM

Paper SS2+NS+BI+EL-TuM10
Growth Process and Thermal Stability of Semifluorinated Alkanethiol Self-Assembled Monolayers on Au(111)

Tuesday, October 3, 2000, 11:20 am, Room 209

Session: Self-Assembled Monolayers
Presenter: M. Hara, Frontier Research System, RIKEN, Japan
Authors: M. Hara, Frontier Research System, RIKEN, Japan
A. Suzuki, Tokyo Institute of Technology, Japan
K. Tamada, National Institute of Materials and Chemistry, Japan
H. Fukushima, Seiko Epson Co., Japan
T.R. Lee, University of Houston
Correspondent: Click to Email
Growth process and thermal stability of semifluorinated alkanethiol (CF@sub 3@(CF@sub 2@)@sub m@(CH@sub 2@)@sub n@SH) self-assembled monolayers (SAMs) on Au(111) have been investigated by thermal desorption spectroscopy (TDS) and scanning tunneling microscopy (STM). The growth kinetics showed nearly the Langmuir adsorption isotherm and the etch pits were formed in the upright phase, while the striped phases were not observed in the initial growth stage for shorter (CH@sub 2@)@sub n@ semifluorinated SAMs. In TDS, no significant peaks can be obtained for dimer molecules and decomposed species, suggesting no associative desorption nor dimerization and thermal stability of the semifluorinated molecules during heating up to 650 K. Since longer (CH@sub 2@)@sub n@ semifluorinated SAMs remained the same chemisorbed state in the monolayer after annealing at around 480 K, it has been confirmed that also the alkyl chain part plays an important role for the thermal stability and the ordering in the semifluorinated alkanethiol SAMs. Following those results, we propose more detailed surface phase transition model of semifluorinated alkanethiol SAMs in the growth and annealing processes.