Determination of the spring constants of probes for force microscopy/spectroscopy

Abstract

A direct, accurate and convenient procedure for calibrating the spring constants of probes used for force microscopy/spectroscopy is described. It amounts to deflecting an `unknown' cantilever with a `standard' lever, where the standard lever has been precalibrated. The absolute and relative accuracies of the procedure are - 30% and - 20%, respectively; the former is limited by uncertainties in the determination of the spring constant for the `standard' lever, as well as that for the `unknown'. The method differs from others of the static deflection variety by its exploitation of the routine features of current instruments. The technique is compared with other static and dynamic methods currently being used.

Force measurements with the atomic force microscope: Technique, interpretation and applications

“…In practice it is often more convenient to calibrate a reference cantilever accurately and then use this reference to calibrate all other cantilevers by pressing them against the reference cantilever (Fig. 7) [100]. Therefore one of the cantilevers is mounted on a piezoelectric translator.…”

Direct observation of self-assembled chain-like water structures in a nanoscopic water meniscus

“…Considering the Page 17 of 25 capability of COIFM method in measuring forces with high resolution and controlling gap-distance with high precision, the water meniscus in air may present unprecedented model systems to study biological functions such as water channels through transmembrane pores. For these studies, the use of a calibrated spring constant instead of using a nominal spring constant would provide more precise force values as the nominal constant may lead to force error by 20-30% on a given wafer 89 . As seen in the transition periodicity increases under the lateral modulation (thus the increases of the effective temperature), 47 oscillatory force measurements at various controlled temperatures would allow better understanding of chain-like water structures and their kinetically activated processes.…”

Surface force spectroscopic point load measurements and viscoelastic modelling of the micromechanical properties of air flow sensitive hairs of a spider (Cupiennius salei)

“…The loss of contact between the two measurements provided a reference point when quantifying the total deflection of the hair during a measurement. The spring constants of the AFM cantilevers were calibrated using the standard 'tip-on-tip' method, as well as the thermal tuning method for softer cantilevers (Hutter & Bechhoefer 1993a,b;Gibson et al 1996;Hazel & Tsukruk 1998.…”