Detailed modeling of the adhesion force between an AFM tip and a smooth flat surface under different humidity levels

Sheng Chao Chen, Jen-Fin Lin

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

Adhesion forces between a probe tip and a flat surface under humid conditions are usually evaluated using the geometric model of the water bridge profile. However, the force equilibrium of the water/air film must exist since the film is in a stationary state and thermodynamic equilibrium. In the present study, a sophisticated numerical model, which is based on both geometry constraints and the force equilibrium of the water/air film, is proposed to compute adhesion forces. The results obtained are in good agreement with the experimental results by pull-off tests presented in the literature. The maximum separation distance can be evaluated using the present model. When the contact angle of the tip equals that of the flat surface, the tip radius, rather than the humidity level, dominates the adhesion force. The capillary pressure force was found to be a major component of the adhesion force at low humidity levels. The surface tension force significantly increased when the relative humidity was increased.

Original languageEnglish
Article number115006
JournalJournal of Micromechanics and Microengineering
Volume18
Issue number11
DOIs
Publication statusPublished - 2008 Nov 1

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Mechanics of Materials
  • Mechanical Engineering
  • Electrical and Electronic Engineering

Fingerprint Dive into the research topics of 'Detailed modeling of the adhesion force between an AFM tip and a smooth flat surface under different humidity levels'. Together they form a unique fingerprint.

  • Cite this