In this work, we present a new theoretical model for use in contact resonance atomic force microscopy. This model incorporates the effects of a long, massive sensing tip and is especially useful to interpret operation in the so-called trolling mode. The model is based on traditional Euler–Bernoulli beam theory, whereby the effect of the tip as well as of the sample in contact, modeled as an elastic substrate, are captured by appropriate boundary conditions. A novel interpretation of the flexural and torsional modes of vibration of the cantilever, when not in contact with the sample, is used to estimate the inertia properties of the long, massive tip. Using this information, sample elastic properties are then estimated from the in-contact resonance frequencies of the system. The predictive capability of the proposed model is verified via finite element analysis. Different combinations of cantilever geometry, tip geometry, and sample stiffness are investigated. The model’s accurate predictive ranges are discussed and shown to outperform those of other popular models currently used in contact resonance atomic force microscopy.
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Experimental validation of contact resonance AFM using long massive tips
Abstract In this work, we present an experimental validation of a new contact resonance atomic force microscopy model developed for sensors with long, massive tips. A derivation of a new technique and graphical method for the identification of the unknown system parameters is presented. The technique and contact resonance model are experimentally validated. The agreement between our contact resonance experimental measurements and values obtained from nanoindentation show a minimal error of 1.4%–4.5% and demonstrate the validity of the new contact resonance model and system parameter identification technique.
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- Award ID(s):
- 1934772
- NSF-PAR ID:
- 10440078
- Date Published:
- Journal Name:
- Nanotechnology
- Volume:
- 34
- Issue:
- 36
- ISSN:
- 0957-4484
- Page Range / eLocation ID:
- 365712
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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