Effect of intrinsic instability of cantilevers on static mode Atomic Force Spectroscopy

TL;DR

This paper demonstrates that intrinsic cantilever instability significantly alters static mode Atomic Force Spectroscopy curves, affecting measurements like jump-off-contact, and introduces a model validated by electric field experiments.

Contribution

It reveals the impact of intrinsic cantilever instability on static AFM force curves and proposes a model to explain this effect, validated through electric field experiments.

Findings

Intrinsic cantilever instability modifies force spectroscopy curves

The step-size of sample movement influences the curves

Electric field application validates the proposed model

Abstract

We show that the static force spectroscopy curve is significantly modified due to presence of intrinsic cantilever instability. This instability acts in tandem with such instabilities like water bridge or molecular bond rupture and makes the static force spectroscopy curve (including "jump-off-contact") dependent on the step-size of the movement of sample stage. A model has been proposed to explain the data. This has been further validated by applying an electric field between tip and substrate which modifies the tip-substrate interaction.