Accuracy of tip-sample interaction measurements using dynamic atomic force microscopy techniques: Dependence on oscillation amplitude, interaction strength, and tip-sample distance
Accuracy of tip-sample interaction measurements using dynamic atomic force microscopy techniques: Dependence on oscillation amplitude, interaction strength, and tip-sample distance
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DOI：
10.1063/1.5089634
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发表时间：
2019-03-01
影响因子：
1.6
通讯作者：
Schwarz, Udo D.
中科院分区：
文献类型：
--
作者：
Dagdeviren, Omur E.;Schwarz, Udo D.
原子力显微镜(AFM)是一种多功能的表面表征方法，它可以以高空间分辨率绘制样品的表面形貌，同时通过对样品和探针尖端之间的作用力进行特定位置的高分辨率量化来询问其表面化学。由于原子力显微镜测量技术的长足进步，这种化学性质的局部测量在近年来得到了很大的普及。为此，实现了动态原子力显微镜方法，其中记录作为尖端-样品距离的函数的振动悬臂梁的振荡频率或振荡幅度和相位，并随后转换为反映尖端-样品力或相互作用势。然而，当应用最常用的数学转换程序时，如果振荡幅度是相互作用的衰减长度的量级，则这种转换已被证明产生了不可忽略的误差。在这些早期发现的基础上，本文提出的计算研究表明，偏离实际值的程度还可能关键地取决于尖端-样品相互作用的总体强度和获得相互作用的距离。然而，这些系统误差可以通过使用足够大于相互作用势的衰减长度的振荡幅度来有效地消除。由AIP出版公司授权出版。
Atomic force microscopy (AFM) is a versatile surface characterization method that can map a sample's topography with high spatial resolution while simultaneously interrogating its surface chemistry through the site-specific high-resolution quantification of the forces acting between the sample and the probe tip. Thanks to considerable advances in AFM measurement technology, such local measurements of chemical properties have gained much popularity in recent years. To this end, dynamic AFM methodologies are implemented where either the oscillation frequency or the oscillation amplitude and phase of the vibrating cantilever are recorded as a function of tip-sample distance and subsequently converted to reflect tip-sample forces or interaction potentials. Such conversion has, however, been shown to produce non-negligible errors when applying the most commonly used mathematical conversion procedures if oscillation amplitudes are of the order of the decay length of the interaction. Extending on these earlier findings, the computational study presented in this paper reveals that the degree of divergence from actual values may also critically depend on both the overall strength of tip-sample interaction and the distance at which the interaction is obtained. These systematic errors can, however, be effectively eliminated by using oscillation amplitudes that are sufficiently larger than the decay length of the interaction potential. Published under license by AIP Publishing.