Cantilever signature of tip detachment during contact resonance AFM

Beilstein Journal of Nanotechnology

article

Devin Kalafut¹  Ryan Wagner¹  Maria Jose Cadena¹  Anil Bajaj¹  Arvind Raman¹ 

[1] School of Mechanical Engineering, Purdue University

关键词: atomic force microscopy (AFM);    contact resonance;    nonlinear normalmode (NNM);    tip–sample detachment;    photothermal excitation;   

DOI  :  10.3762/bjnano.12.96

学科分类：环境监测和分析

来源: Beilstein - Institut zur Foerderung der Chemischen Wissenschaften

【 摘 要 】

Contact resonance atomic force microscopy, piezoresponse force microscopy, and electrochemical strain microscopy are atomicforce microscopy modes in which the cantilever is held in contact with the sample at a constant average force while monitoring thecantilever motion under the influence of a small, superimposed vibrational signal. Though these modes depend on permanent contact, there is a lack of detailed analysis on how the cantilever motion evolves when this essential condition is violated. This is not anuncommon occurrence since higher operating amplitudes tend to yield better signal-to-noise ratio, so users may inadvertentlyreduce their experimental accuracy by inducing tip–sample detachment in an effort to improve their measurements. We shed lighton this issue by deliberately pushing both our experimental equipment and numerical simulations to the point of tip–sample detachment to explore cantilever dynamics during a useful and observable threshold feature in the measured response. Numerical simulations of the analytical model allow for extended insight into cantilever dynamics such as full-length deflection and slope behavior,which can be challenging or unobtainable in a standard equipment configuration. With such tools, we are able to determine the cantilever motion during detachment and connect the qualitative and quantitative behavior to experimental features.

【 授权许可】

CC BY