Help Privacy Policy Disclaimer
  Advanced SearchBrowse




Journal Article

Modification of alkanethiolate self-assembled monolayers by free radical-dominant plasma


Grunze,  Michael
Cellular Biophysics, Max Planck Institute for Medical Research, Max Planck Society;

Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available

Liao, J.-D., Wang, M.-C., Weng, C.-C., Klauser, R., Frey, S., Zharnikov, M., et al. (2002). Modification of alkanethiolate self-assembled monolayers by free radical-dominant plasma. The Journal of Physical Chemistry B, 106(1), 77-84. doi:10.1021/jp011119c.

Cite as: https://hdl.handle.net/21.11116/0000-0001-BE28-D
Synchrotron-based high-resolution photoelectron spectroscopy was applied to study the modification of the alkanethiol (AT) self-assembled monolayers on gold and silver substrates by nitrogen−oxygen downstream microwave plasma. Because of the low density and energy of the ionizing particles, the long-lived nitrogen and oxygen radicals provided the major impact of plasma treatment. The treatment resulted in massive damage and disordering of the initially well-ordered and chemically homogeneous AT films. The most pronounced processes are the complete (AT/Au) or partial (AT/Ag) oxidation of the pristine thiolate species, partial desorption of hydrogen and carbon-containing fragments with subsequent cross-linking within the residual hydrocarbon layer, and partial oxidation of this layer, and appearance of the nitrogen-containing entities. The plasma-treatment-induced changes in the alkyl matrix and at the S−substrate interface are only partly correlated. The rate and extent of the oxidation processes at this interface are noticeably larger for C18/Au than for C18/Ag, which suggests a stronger S−metal bond in the latter system. The results demonstrate that a smallest oxygen contamination should be avoided if one wants to perform a soft modification of thin organic layers or definite molecular entities attached to these layers through the exposure to plasma.