Surface characterization and electrochemical properties of alkyl, fluorinated alkyl, and alkoxy monolayers on silicon

Citation
Cj. Barrelet et al., Surface characterization and electrochemical properties of alkyl, fluorinated alkyl, and alkoxy monolayers on silicon, LANGMUIR, 17(11), 2001, pp. 3460-3465
Citations number
32
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
LANGMUIR
ISSN journal
07437463 → ACNP
Volume
17
Issue
11
Year of publication
2001
Pages
3460 - 3465
Database
ISI
SICI code
0743-7463(20010529)17:11<3460:SCAEPO>2.0.ZU;2-9
Abstract
Alkyl and fluorinated alkyl monolayers covalently bonded to the silicon (11 1) surface have been prepared by UV illumination of the H-Si(111) surface w hile immersed in a solution of olefin precursor under high vacuum. An alkox y monolayer covalently bonded to the silicon (111) surface is formed by the reaction of the H-Si(111) surface with a heated solution of primary alcoho l precursors under high vacuum. Ellipsometry, X-ray photoelectron spectrosc opy, and atomic force microscopy are used to characterize the three monolay ers. The alkyl monolayer is measured to have the largest number of organic adsorbates per surface silicon atom. Properties of the monolayers on the si licon surface are probed by cyclic voltammetry. The hydrophobic alkyl monol ayer slows the oxidation of the silicon surface by water. The three monolay ers also slow the rate of electron transfer across the silicon-electrolyte interface by acting as a tunneling barrier. The alkyl monolayer in tetrahyd rofuran exhibits a large and reproducible blocking of the electron transfer .