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Title: Phosphonate self-assembled monolayers on aluminum surfaces

Abstract

Substrates of aluminum (Al) deposited by physical vapor deposition onto Si substrates and then chemically reacted with perfluorodecylphosphonic acid (PFDP/Al/Si), decylphosphonic acid (DP/Al/Si), and octadecylphosphonic acid (ODP/Al/Si) were studied by x-ray photoelectron spectroscopy (XPS), contact angle measurements, atomic force microscopy (AFM), and friction force microscopy, a derivative of AFM, to characterize their surface chemical composition, roughness, and micro-/nanotribological properties. XPS analysis confirmed the presence of perfluorinated and nonperfluorinated alkylphosphonate molecules on the PFDP/Al/Si, DP/Al/Si, and ODP/Al/Si. The sessile drop static contact angle of pure water on PFDP/Al/Si was typically more than 130 deg. and on DP/Al/Si and ODP/Al/Si typically more than 125 deg. indicating that all phosphonic acid reacted Al/Si samples were very hydrophobic. The surface roughness for PFDP/Al/Si, DP/Al/Si, ODP/Al/Si, and bare Al/Si was approximately 35 nm as determined by AFM. The surface energy for PFDP/Al/Si was determined to be approximately 11 mN/m by the Zisman plot method compared to 21 and 20 mN/m for DP/Al/Si and ODP/Al/Si, respectively. Tribology involves the measure of lateral forces due to friction and adhesion between two surfaces. Friction, adhesion, and wear play important roles in the performance of micro-/nanoelectromechanical systems. PFDP/Al/Si gave the lowest adhesion and coefficient of friction values while baremore » Al/Si gave the highest. The adhesion and coefficient of friction values for DP/Al/Si and ODP/Al/Si were comparable.« less

Authors:
; ; ; ; ;  [1];  [2];  [2];  [2];  [3]
  1. LMCH, IMX, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)
  2. (EPFL), CH-1015 Lausanne (Switzerland)
  3. (NLIM), Ohio State University, 650 Ackeman Road, Suite 255, Columbus, Ohio 43202 (United States)
Publication Date:
OSTI Identifier:
20783272
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 124; Journal Issue: 17; Other Information: DOI: 10.1063/1.2186311; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 36 MATERIALS SCIENCE; ADHESION; ALUMINIUM; ATOMIC FORCE MICROSCOPY; CHEMICAL ANALYSIS; CHEMICAL REACTIONS; FRICTION; PHOSPHONIC ACIDS; PHYSICAL VAPOR DEPOSITION; SILICON; SURFACE ENERGY; TRIBOLOGY; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Hoque, E., DeRose, J.A., Hoffmann, P., Mathieu, H.J., Bhushan, B., Cichomski, M., LTCM, ISE, Ecole Polytechnique Federale de Lausanne, LOA, IOA, Ecole Polytechnique Federale de Lausanne, LMCH, IMX, Ecole Polytechnique Federale de Lausanne, and Nanotribology Laboratory for Information Storage and MEMS/NEMS. Phosphonate self-assembled monolayers on aluminum surfaces. United States: N. p., 2006. Web. doi:10.1063/1.2186311.
Hoque, E., DeRose, J.A., Hoffmann, P., Mathieu, H.J., Bhushan, B., Cichomski, M., LTCM, ISE, Ecole Polytechnique Federale de Lausanne, LOA, IOA, Ecole Polytechnique Federale de Lausanne, LMCH, IMX, Ecole Polytechnique Federale de Lausanne, & Nanotribology Laboratory for Information Storage and MEMS/NEMS. Phosphonate self-assembled monolayers on aluminum surfaces. United States. doi:10.1063/1.2186311.
Hoque, E., DeRose, J.A., Hoffmann, P., Mathieu, H.J., Bhushan, B., Cichomski, M., LTCM, ISE, Ecole Polytechnique Federale de Lausanne, LOA, IOA, Ecole Polytechnique Federale de Lausanne, LMCH, IMX, Ecole Polytechnique Federale de Lausanne, and Nanotribology Laboratory for Information Storage and MEMS/NEMS. Sun . "Phosphonate self-assembled monolayers on aluminum surfaces". United States. doi:10.1063/1.2186311.
@article{osti_20783272,
title = {Phosphonate self-assembled monolayers on aluminum surfaces},
author = {Hoque, E. and DeRose, J.A. and Hoffmann, P. and Mathieu, H.J. and Bhushan, B. and Cichomski, M. and LTCM, ISE, Ecole Polytechnique Federale de Lausanne and LOA, IOA, Ecole Polytechnique Federale de Lausanne and LMCH, IMX, Ecole Polytechnique Federale de Lausanne and Nanotribology Laboratory for Information Storage and MEMS/NEMS},
abstractNote = {Substrates of aluminum (Al) deposited by physical vapor deposition onto Si substrates and then chemically reacted with perfluorodecylphosphonic acid (PFDP/Al/Si), decylphosphonic acid (DP/Al/Si), and octadecylphosphonic acid (ODP/Al/Si) were studied by x-ray photoelectron spectroscopy (XPS), contact angle measurements, atomic force microscopy (AFM), and friction force microscopy, a derivative of AFM, to characterize their surface chemical composition, roughness, and micro-/nanotribological properties. XPS analysis confirmed the presence of perfluorinated and nonperfluorinated alkylphosphonate molecules on the PFDP/Al/Si, DP/Al/Si, and ODP/Al/Si. The sessile drop static contact angle of pure water on PFDP/Al/Si was typically more than 130 deg. and on DP/Al/Si and ODP/Al/Si typically more than 125 deg. indicating that all phosphonic acid reacted Al/Si samples were very hydrophobic. The surface roughness for PFDP/Al/Si, DP/Al/Si, ODP/Al/Si, and bare Al/Si was approximately 35 nm as determined by AFM. The surface energy for PFDP/Al/Si was determined to be approximately 11 mN/m by the Zisman plot method compared to 21 and 20 mN/m for DP/Al/Si and ODP/Al/Si, respectively. Tribology involves the measure of lateral forces due to friction and adhesion between two surfaces. Friction, adhesion, and wear play important roles in the performance of micro-/nanoelectromechanical systems. PFDP/Al/Si gave the lowest adhesion and coefficient of friction values while bare Al/Si gave the highest. The adhesion and coefficient of friction values for DP/Al/Si and ODP/Al/Si were comparable.},
doi = {10.1063/1.2186311},
journal = {Journal of Chemical Physics},
number = 17,
volume = 124,
place = {United States},
year = {Sun May 07 00:00:00 EDT 2006},
month = {Sun May 07 00:00:00 EDT 2006}
}
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