Thermal grafting of fluorinated molecular monolayers on doped amorphous silicon surfaces

Journal Article · Sun Mar 15 00:00:00 EDT 2009 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3095474· OSTI ID:21190109

Sabbah, H; Zebda, A; Ababou-Girard, S; Solal, F; Godet, C ^[1]; Conde, J P; Chu, V ^[2]

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1. Institut de Physique de Rennes (CNRS UMR 6251), Universite Rennes 1, 35042 Rennes (France)
2. INESC Microsistemas e Nanotechnologias and IN-Institute of Nanoscience and Nanotechnology, Rua Alves Redol, 9, 1000-029 Lisboa (Portugal)

Thermally induced (160-300 deg. C) gas phase grafting of linear alkene molecules (perfluorodecene) was performed on hydrogenated amorphous silicon (a-Si:H) films, either nominally undoped or doped with different boron and phosphorus concentrations. Dense and smooth a-Si:H films were grown using plasma decomposition of silane. Quantitative analysis of in situ x-ray photoelectron spectroscopy indicates the grafting of a single layer of organic molecules. The hydrophobic properties of perfluorodecene-modified surfaces were studied as a function of surface coverage. Annealing experiments in ultrahigh vacuum show the covalent binding and the thermal stability of these immobilized layers up to 370 deg. C; this temperature corresponds to the Si-C bond cleavage temperature. In contrast with hydrogenated crystalline Si(111):H, no heavy wet chemistry surface preparation is required for thermal grafting of alkene molecules on a-Si:H films. A threshold grafting temperature is observed, with a strong dependence on the doping level which produces a large contrast in the molecular coverage for grafting performed at 230 deg. C.

• OSTI ID: 21190109
• Journal Information: Journal of Applied Physics, Vol. 105, Issue 6; Other Information: DOI: 10.1063/1.3095474; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALKENES
ANNEALING
BORON
CHEMICAL BONDS
CLEAVAGE
DECOMPOSITION
DISSOCIATION
DOPED MATERIALS
HYDROGEN
LAYERS
PHOSPHORUS
PLASMA
SEMICONDUCTOR MATERIALS
SILANES
SILICON
SURFACE TREATMENTS
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0400-1000 K
THIN FILMS
X-RAY PHOTOELECTRON SPECTROSCOPY