How to measure energy dissipation in dynamic mode atomic force microscopy

Citation
B. Anczykowski et al., How to measure energy dissipation in dynamic mode atomic force microscopy, APPL SURF S, 140(3-4), 1999, pp. 376-382
Citations number
18
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Material Science & Engineering
Journal title
APPLIED SURFACE SCIENCE
ISSN journal
01694332 → ACNP
Volume
140
Issue
3-4
Year of publication
1999
Pages
376 - 382
Database
ISI
SICI code
0169-4332(199902)140:3-4<376:HTMEDI>2.0.ZU;2-I
Abstract
When studying a mechanical system like an atomic force microscope (AFM) in dynamic mode it is intuitive and instructive to analyse the forces involved in tip-sample interaction. A different but complementary approach is based on analysing the energy that is dissipated when the tip periodically inter acts with the sample surface. This method does not require solving the diff erential equation of motion for the oscillating cantilever, but is based en tirely on the analysis of the energy flow in and out of the dynamic system. Therefore the problem of finding a realistic model to describe the tip-sam ple interaction in terms of non-linear force-distance dependencies and damp ing effects is omitted. Instead, it is possible to determine the energy dis sipated by the tip-sample interaction directly by measuring such quantities as oscillation amplitude, frequency, phase shift and drive amplitude. The method proved to be important when interpreting phase data obtained in tapp ing mode, but is also applicable to a variety of scanning probe microscopes operating in different dynamic modes. Additional electronics were designed to allow a direct mapping of local energy dissipation while scanning a sam ple surface. By applying this technique to the cross-section of a polymer b lend a material specific contrast was observed. (C) 1999 Elsevier Science B .V. All rights reserved.