Functional dependence of resonant harmonics on nanomechanical parameters in dynamic mode atomic force microscopy

We present a combined theoretical and experimental study of the dependence of resonant higher harmonics of rectangular cantilevers of an atomic force microscope (AFM) as a function of relevant parameters such as the cantilever force constant, tip radius and free oscillation amplitude as well as the...

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Detalles Bibliográficos
Autores: Gramazio, Federico, Lorenzoni, Matteo|||0000-0001-5287-8761, Pérez-Murano, Francesc, Rull Trinidad, Enrique, Staufer, Urs, Fraxedas, Jordi|||0000-0002-2821-4831
Tipo de recurso: artículo
Fecha de publicación:2017
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:186241
Acceso en línea:https://ddd.uab.cat/record/186241
https://dx.doi.org/urn:doi:10.3762/bjnano.8.90
Access Level:acceso abierto
Palabra clave:Atomic force microscopy
Metrology
Multifrequency
Nanomechanics
Descripción
Sumario:We present a combined theoretical and experimental study of the dependence of resonant higher harmonics of rectangular cantilevers of an atomic force microscope (AFM) as a function of relevant parameters such as the cantilever force constant, tip radius and free oscillation amplitude as well as the stiffness of the sample's surface. The simulations reveal a universal functional dependence of the amplitude of the 6th harmonic (in resonance with the 2nd flexural mode) on these parameters, which can be expressed in terms of a gun-shaped function. This analytical expression can be regarded as a practical tool for extracting qualitative information from AFM measurements and it can be extended to any resonant harmonics. The experiments confirm the predicted dependence in the explored 3-45 N/m force constant range and 2-345 GPa sample's stiffness range. For force constants around 25 N/m, the amplitude of the 6th harmonic exhibits the largest sensitivity for ultrasharp tips (tip radius below 10 nm) and polymers (Young's modulus below 20 GPa).