Department of Materials Science, S N Bose National Centre for Basic Sciences, Kolkata, India.
Nanotechnology. 2010 Jan 29;21(4):045706. doi: 10.1088/0957-4484/21/4/045706. Epub 2009 Dec 16.
We show that the static force spectroscopy curve taken in an atomic force microscope is significantly modified due to presence of intrinsic cantilever instability which occurs as a result of its movement in a nonlinear force field. This instability acts in tandem with such instabilities as water bridge or molecular bond rupture and makes the static force spectroscopy curve (including 'jump-off-contact') dependent on the step size of data collection. A theoretical model has been proposed to explain the data. We emphasize the necessity of taking care of this fundamental instability of the microcantilever in calculating the adhesive force and also in the interpretation of data taken using an atomic force microscope.
我们表明，原子力显微镜中获取的静态力谱曲线由于存在固有悬臂梁不稳定性而发生显著变化，这种不稳定性是由于其在非线性力场中的运动而产生的。这种不稳定性与水桥或分子键断裂等不稳定性协同作用，使得静态力谱曲线（包括“脱离接触”）取决于数据采集的步长。已经提出了一个理论模型来解释这些数据。我们强调在计算粘附力时以及在解释使用原子力显微镜获取的数据时，必须注意微悬臂梁的这种基本不稳定性。
