Web Release Date: October 4,
Enhancement of Topographic Images Obtained in Liquid Media by Atomic Force Microscopy
and
Department of Chemical Engineering, Kwangwoon University, 447-1, Wolgye, Nowon, Seoul 139-701, Korea, School of Chemical and Biological Engineering, Seoul National University, San 56-1, Shillim, Kwanak, Seoul 151-742, Korea
Received: June 9, 2006
In Final Form: August 28, 2006
Abstract:
The open liquid-cell atomic force microscope (AFM) has potential for studies of biomaterials and surface
morphology in liquid media, and a variety of fluids can be used as buffer solutions. The dependence of
image distortion on fluid properties (kinematic viscosity) has been studied with edge friction force obtained
in lateral images and will shortly appear elsewhere [Appl. Phys. Lett. 2006, 88, 173121]. Previous studies
indicate that the scan rate should be slower for obtaining a nondistorted image. However, the time required
for the scan is greatly increased. Therefore, we introduced the vector concept to evaluate the net force for
scanning in the y-direction and found two solutions to achieve a zero force difference introduced by the
cantilever-fluid and the tip-surface. When the scan rate approaches zero or a specific velocity (30 
m/s in
this study), the force of the interaction induced by the cantilever-fluid and tip-surface is reduced to a
considerable extent. Among the two solutions, a scan with a specific velocity is an easy, rapid method for
obtaining a nondistorted image, compared to the previously proposed method (scan rate approaches zero).
This proposed model was confirmed in a proof-of-concept test using 2-propanol.
Download the full text: PDF | HTML
