Abstract
Local elastic compliance of organic monolayers (octadecyltriethoxysilane/mica and alkanethiol/gold) has been investigated with nanometer resolution by applying a force modulation technique to an atomic force microscope. Systematic measurements were taken as a function of modulation frequency and amplitude, as well as the local environment surrounding the surface. The topography and local elasticity of the monolayers are contrasted to the bare substrate created by the tip of the atomic force microscope at high imaging force. Under ambient laboratory conditions, the Young's modulus of mica calculated from the elasticity images is lower than the organic monolayer. Such an observation is not intuitive and can be explained by the thin film of water adsorbed on mica. Water adsorption can change the microscope tip surface interaction. As a result, mica appears as a softer surface than the organic layers. In addition, the elasticity is dramatically enhanced if the modulation frequency coincides with or is close to the natural resonance frequency of the tips of the atomic force microscope. Measurements taken under liquid provide more reproducible and accurate results because the resonance frequency is damped out and capillary interactions are avoided. The measured Young's modulus is also found to increase slightly with increasing modulation amplitude.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 383-389 |
| Number of pages | 7 |
| Journal | Surface and Interface Analysis |
| Volume | 25 |
| Issue number | 6 |
| State | Published - Jun 1997 |
| Externally published | Yes |
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Keywords
- Atomic force microscopy (AFM)
- Elastic compliance
- Elasticity
- Force modulation microscopy
- Self-assembled monolayers
ASJC Scopus subject areas
- Colloid and Surface Chemistry
- Physical and Theoretical Chemistry
Cite this
Nanometer-scale elasticity measurements on organic monolayers using scanning force microscopy. / Kiridena, Waruna; Jain, Vijay; Kuo, P. K.; Liu, Gang-yu.
In: Surface and Interface Analysis, Vol. 25, No. 6, 06.1997, p. 383-389.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Nanometer-scale elasticity measurements on organic monolayers using scanning force microscopy
AU - Kiridena, Waruna
AU - Jain, Vijay
AU - Kuo, P. K.
AU - Liu, Gang-yu
PY - 1997/6
Y1 - 1997/6
N2 - Local elastic compliance of organic monolayers (octadecyltriethoxysilane/mica and alkanethiol/gold) has been investigated with nanometer resolution by applying a force modulation technique to an atomic force microscope. Systematic measurements were taken as a function of modulation frequency and amplitude, as well as the local environment surrounding the surface. The topography and local elasticity of the monolayers are contrasted to the bare substrate created by the tip of the atomic force microscope at high imaging force. Under ambient laboratory conditions, the Young's modulus of mica calculated from the elasticity images is lower than the organic monolayer. Such an observation is not intuitive and can be explained by the thin film of water adsorbed on mica. Water adsorption can change the microscope tip surface interaction. As a result, mica appears as a softer surface than the organic layers. In addition, the elasticity is dramatically enhanced if the modulation frequency coincides with or is close to the natural resonance frequency of the tips of the atomic force microscope. Measurements taken under liquid provide more reproducible and accurate results because the resonance frequency is damped out and capillary interactions are avoided. The measured Young's modulus is also found to increase slightly with increasing modulation amplitude.
AB - Local elastic compliance of organic monolayers (octadecyltriethoxysilane/mica and alkanethiol/gold) has been investigated with nanometer resolution by applying a force modulation technique to an atomic force microscope. Systematic measurements were taken as a function of modulation frequency and amplitude, as well as the local environment surrounding the surface. The topography and local elasticity of the monolayers are contrasted to the bare substrate created by the tip of the atomic force microscope at high imaging force. Under ambient laboratory conditions, the Young's modulus of mica calculated from the elasticity images is lower than the organic monolayer. Such an observation is not intuitive and can be explained by the thin film of water adsorbed on mica. Water adsorption can change the microscope tip surface interaction. As a result, mica appears as a softer surface than the organic layers. In addition, the elasticity is dramatically enhanced if the modulation frequency coincides with or is close to the natural resonance frequency of the tips of the atomic force microscope. Measurements taken under liquid provide more reproducible and accurate results because the resonance frequency is damped out and capillary interactions are avoided. The measured Young's modulus is also found to increase slightly with increasing modulation amplitude.
KW - Atomic force microscopy (AFM)
KW - Elastic compliance
KW - Elasticity
KW - Force modulation microscopy
KW - Self-assembled monolayers
UR - http://www.scopus.com/inward/record.url?scp=0031166821&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0031166821&partnerID=8YFLogxK
M3 - Article
VL - 25
SP - 383
EP - 389
JO - Surface and Interface Analysis
JF - Surface and Interface Analysis
SN - 0142-2421
IS - 6
ER -