Effects of Surface Free Energy and Relative Humidity on Friction and Image Contrast Measured with Lateral Force Microscopy

Published

March 3, 2010

Author(s)

Tinh Nguyen, Lijiang Chen, Xiaohong Gu

Abstract

Effects of sample surface free energy (s) and relative humidity (RH) of the tip-sample environment on image contrast and friction characteristics measured with lateral force microscopy (LFM) have been investigated. Samples having a wide range of surface free energies were fabricated by combining microcontact printing, silane vapor deposition, and UV/O3 treatment. Humidity in the tip-sample environment was controlled using a chamber enclosing the AFM head. The friction difference between two chemically-different domains increases slightly at low RH, reaches a maximum at elevated RH, and then decreases. This friction behavior is proportional to the s difference of the two domains. The LFM image contrast between domains follows closely with their s difference. By optimizing RH, LFM is found to be capable of discerning two domains having a difference in their surface free energy as small as 6.4 mJ/m2. The enhanced image contrast at elevated RHs is attributed to the capillary force, which is a function of surface free energy of the sample.

Proceedings Title

Adhesion Society Meeting

Conference Dates

February 21-24, 2010

Conference Location

Daytona Beach , FL

Pub Type

Conferences

Keywords

AFM, friction, chemical, humidity, imaging, surface free energy

Citation

Nguyen, T. , chen, L. and Gu, X. (2010), Effects of Surface Free Energy and Relative Humidity on Friction and Image Contrast Measured with Lateral Force Microscopy, Adhesion Society Meeting, Daytona Beach , FL (Accessed April 24, 2024)