From images to interactions: high-resolution phase imaging in tapping-mode atomic force microscopy.

M Stark; C Möller; D J Müller; R Guckenberger

doi:10.1016/s0006-3495(01)76266-2

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PubMed · 11371473

From images to interactions: high-resolution phase imaging in tapping-mode atomic force microscopy.

M Stark·C Möller·D J Müller·R Guckenberger

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Abstract

In tapping-mode atomic force microscopy, the phase shift between excitation and response of the cantilever is used as a material-dependent signal complementary to topography. The localization of information in the phase signal is demonstrated with 1.4-nm lateral resolution on purple membrane of Halobacterium salinarum in buffer solution. In a first-order approximation, the phase signal is found to correlate with modulations of the tip oscillation amplitude, induced by topography. Extending the analysis to contributions of the tip-sample interaction area as a second-order approximation, a method is proposed to extract information about the interaction from the phase signal for surfaces with a roughness in the order of the tip radius.

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Buffers Halobacterium salinarum Image Processing, Computer-Assisted Microscopy, Atomic Force Purple Membrane Sensitivity and Specificity Solutions Thermodynamics Journal Article Research Support, Non-U.S. Gov't

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M Stark, C Möller, D J Müller, R Guckenberger. 2001. From images to interactions: high-resolution phase imaging in tapping-mode atomic force microscopy.. https://doi.org/10.1016/s0006-3495(01)76266-2

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