Nanoscale elasticity measurement with in situ tip shape estimation in atomic force microscopy
- 1 June 2000
- journal article
- research article
- Published by AIP Publishing in Review of Scientific Instruments
- Vol. 71 (6), 2403-2408
- https://doi.org/10.1063/1.1150627
Abstract
For a quantitative evaluation of nanoscale elasticity, atomic force microscopy, and related methods measure the contact stiffness (or force gradient) between the tip and sample surface. In these methods the key parameter is the contact radius, since the contact stiffness is changed not only by the elasticity of the sample but also by the contact radius. However, the contact radius is very uncertain and it makes the precision of measurements questionable. In this work, we propose a novel in situ method to estimate the tip shape and the contact radius at the nanoscale contact of the tip and sample. Because the measured resonance frequency sometimes does not depend so sensitively on the contact force as expected from the parabolic tip model, we introduced a more general model of an axial symmetric body and derived an equation for the contact stiffness. Then, the parameters in the model are unambiguously determined from a contact force dependence of the cantilever resonance frequency. We verified that this method is able to provide an accurate prediction of the cantilever thickness, the tip shape, and the effective elasticity of soft and rigid samples.Keywords
This publication has 24 references indexed in Scilit:
- Quantitative elasticity evaluation by contact resonance in an atomic force microscopeApplied Physics A, 1998
- Vibrational dynamics of force microscopy: Effect of tip dimensionsApplied Physics Letters, 1997
- Determination of complex modulus by atomic force microscopyJournal of Applied Physics, 1997
- Vibrations of free and surface-coupled atomic force microscope cantilevers: Theory and experimentReview of Scientific Instruments, 1996
- The Role of Stress in Amorphous Magnetic Materials*Japanese Journal of Applied Physics, 1996
- Plastic Deformation of Nanometer-Scale Gold Connective NecksPhysical Review Letters, 1995
- Acoustic microscopy by atomic force microscopyApplied Physics Letters, 1994
- Atomic force microscopy at MHz frequenciesAnnalen der Physik, 1994
- Imaging viscoelasticity by force modulation with the atomic force microscopeBiophysical Journal, 1993
- Atomic Force MicroscopePhysical Review Letters, 1986