Model of the cantilever used in Atomic Force Microscopy

conference paper

English

New types of weak forces measurements with Atomic Force Microscope (AFM) are very challenging for experimental physics and call for new studies on control strategies operating the AFM. It is thus necessary to first develop a precise model of the cantilever with its sharp tip, in interaction with the scanned sample. This paper presents a model of the cantilever, that is based on beam theory and taking into account the influence of the long distance interaction forces. Developed multi mode cantilever model is capable to describe the behaviour of the real measuring system with good precision. Model is taking into a consideration the influence of higher harmonics and their share on the total tip displacement of the cantilever. Simulated frequency spectra is fully fitting to theoretical expectation and has been successfully confronted with measured data on the real system with a cantilever of same dimensions and properties. For a better understanding of the interaction and its impact on cantilever behaviour a simple interaction model has been build using interaction forces approximations. Simulated approach curve has good match with measured approach curve on Digital Instrument atomic force microscope. The created model reach appropriate accuracy to be helpful tool for further design of control systems improving performance of the AFM.

Atomic Force Microscopy, cantilever, model

HROUZEK, M.

2004

16. 11. 2004

CNRS, CEA

Grenoble

82

82

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