The effects of humidity and surface free energy on adhesion force between atomic force microscopy tip and a silane self-assembled monolayer film

2010 ◽  
Vol 25 (3) ◽  
pp. 556-562 ◽  
Author(s):  
Chien-Chao Huang ◽  
Lijiang Chen ◽  
Xiaohong Gu ◽  
Minhua Zhao ◽  
Tinh Nguyen ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Free Energy ◽  
Surface Free Energy ◽  
Adhesion Force ◽  
Capillary Condensation ◽  
Self Assembled Monolayer ◽  
Force Microscopy ◽  
Atomic Force ◽  
Rate Of Increase ◽  
Self Assembled

The relationship between atomic force microscopy probe-sample adhesion force and relative humidity (RH) at five different levels of surface free energy (γs) of an organic self-assembled monolayer (SAM) has been investigated. Different γs levels were achieved by exposing a patterned SiO2/CH3-terminated octyldimethylchlorosilane SAM sample to an ultraviolet (UV)/ozone atmosphere. A model consisting of the Laplace-Kelvin theory for capillary condensation for nanosized probe and probe-sample molecular interaction was derived to describe the adhesion force as a function of RH from 25 to 90% for different SAM γs values. The equations were solved analytically by using an equivalent curvature of the probe tip shape. Experimental results show that the adhesion force increases slightly with RH for nonpolar SAM. However, for polar SAM surfaces, it increases at first, reaches a maximum, and then decreases. Both the rate of increase and the maximum of the adhesion force with humidity are γs-dependent, which is in good agreement with theoretical prediction. The large rise in the adhesion force in this RH range is due to the capillary force.

Comparative Study of Field Emission-Scanning Electron Microscopy and Atomic Force Microscopy to Assess Self-assembled Monolayer Coverage on Any Type of Substrate

1999 ◽  
Vol 5 (6) ◽  
pp. 413-419 ◽  
Author(s):  
Bernardo R.A. Neves ◽  
Michael E. Salmon ◽  
Phillip E. Russell ◽  
E. Barry Troughton
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Atomic Force Microscopy ◽  
Comparative Study ◽  
Field Emission ◽  
Self Assembled Monolayer ◽  
Force Microscopy ◽  
Atomic Force ◽  
Self Assembled ◽  
Scanning Electron

Abstract: In this work, we show how field emission–scanning electron microscopy (FE-SEM) can be a useful tool for the study of self-assembled monolayer systems. We have carried out a comparative study using FE-SEM and atomic force microscopy (AFM) to assess the morphology and coverage of self-assembled monolayers (SAM) on different substrates. The results show that FE-SEM images present the same qualitative information obtained by AFM images when the SAM is deposited on a smooth substrate (e.g., mica). Further experiments with rough substrates (e.g., Al grains on glass) show that FE-SEM is capable of unambiguously identifying SAMs on any type of substrate, whereas AFM has significant difficulties in identifying SAMs on rough surfaces.

Adhesion and Friction at Graphene/Self-Assembled Monolayer Interfaces Investigated by Atomic Force Microscopy

2017 ◽  
Vol 121 (10) ◽  
pp. 5635-5641 ◽  
Author(s):  
Meagan B. Elinski ◽  
Benjamin D. Menard ◽  
Zhuotong Liu ◽  
James D. Batteas
Keyword(s):  
Atomic Force Microscopy ◽  
Self Assembled Monolayer ◽  
Force Microscopy ◽  
Atomic Force ◽  
Self Assembled

Atomic Force Microscopy of Self-Assembled Nanostructures of TPPS4 on SAM Substrates

2004 ◽  
Vol 97-98 ◽  
pp. 195-200 ◽  
Author(s):  
R. Augulis ◽  
R. Valiokas ◽  
B. Liedberg ◽  
R. Rotomskis
Keyword(s):  
Atomic Force Microscopy ◽  
Substrate Surface ◽  
Self Assembled Monolayer ◽  
Force Microscopy ◽  
Polar Groups ◽  
Atomic Force ◽  
Adsorption Of Organic Molecules ◽  
J Aggregates ◽  
Self Assembled ◽  
Highly Correlated

The adsorption of organic molecules on solid surfaces is one of the fundamental processes for the development of molecular-based nanodevices. Here we focus on the adsorption and ordering of the TPPS4-based J-aggregates on silicon and gold as well as on self-assembled monolayer (SAM) surfaces. The SAMs used for the experiments were based on the chemisorption of thiol containing compounds onto gold. Long ω-substituted alkanethiols are spontaneously assembled on gold to form highly ordered and densely packed layers with controllable chemical and physical properties. TPPS4 J-aggregates were dispersed on SAM surfaces, and on plain gold and silicon substrates for comparison. The dimensions of aggregates, measured by means of atomic force microscopy, varied depending on the type of substrate. Long stripe-like aggregates were flattened on the substrate surface, and the height and width of aggregates highly correlated with the polarity of surface groups. For example, the J-aggregates were narrower on hydrophobic substrates (with non-polar groups) and wider on hydrophilic substrates (with polar groups). These observations support the hypothesis, that TPPS4 forms .soft. cylindrical aggregates, that appear flattened on the substrate.

Production of Nanopatterns by a Combination of Electron Beam Lithography and a Self-Assembled Monolayer for an Antibody Nanoarray

2007 ◽  
Vol 7 (2) ◽  
pp. 410-417 ◽  
Author(s):  
Guo-Jun Zhang ◽  
Takashi Tanii ◽  
Yuzo Kanari ◽  
Iwao Ohdomari
Keyword(s):  
Atomic Force Microscopy ◽  
Electron Beam ◽  
Electron Beam Lithography ◽  
High Specificity ◽  
Nonspecific Binding ◽  
Self Assembled Monolayer ◽  
Incubation Condition ◽  
Force Microscopy ◽  
Atomic Force ◽  
Self Assembled

We report on a flexible method of producing antibody (IgG) nanopatterns by combining electron beam (EB) lithography and a perfluorodecyltriethoxysilane (FDTES) self-assembled monolayer (SAM). Using EB lithography of the FDTES SAM, we easily fabricated IgG patterns with feature sizes on the order of 100 nm. The patterned IgG retained its ability to interact specifically with an anti-IgG. The influence of different concentrations of the IgG and anti-IgG on the resulting fluorescent IgG arrays was investigated. These IgG nanopatterns appeared to be remarkably well controlled and showed almost no detectable nonspecific binding of proteins on a hydrophobic SAM under a suitable incubation condition, characterized by atomic force microscopy, and epi-fluorescence microscopy. The technique enables the realization of high-throughput protein nanoscale arrays with high specificity.

Sign in / Sign up

Export Citation Format

Share Document