Atomic-scale sharpening of silicon tips in noncontact atomic force microscopy -: art. no. 016101
Atomic-scale sharpening of silicon tips in noncontact atomic force microscopy -: art. no. 016101
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DOI：
10.1103/physrevlett.96.016101
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发表时间：
2006-01-13
影响因子：
8.6
通讯作者：
Fuchs, H
中科院分区：
文献类型：
--
作者：
Caciuc, V;Hölscher, H;Fuchs, H
非接触原子力显微镜 (NC-AFM) 中使用的清洁硅尖端的原子尺度稳定性是通过基于密度泛函理论的从头计算来模拟的。尖端结构由具有[111]和[001]端接的硅簇建模。对于通常假设的 Si(111) 型尖端，我们在第一次接近和缩回循环期间观察到通过短程化学力使最初钝的尖端变得锋利。与这种内在过程相对应的结构变化是不可逆的，并导致稳定的 NC-AFM 成像条件。与文献中使用的图片相反，Si(001) 型尖端并未表现出所谓的“双悬挂键”特征，如块状终端所暗示的那样。
The atomic-scale stability of clean silicon tips used in noncontact atomic force microscopy (NC-AFM) is simulated by ab initio calculations based on density functional theory. The tip structures are modeled by silicon clusters with [111] and [001] termination. For the often assumed Si(111)-type tip we observe the sharpening of the initially blunt tip via short-range chemical forces during the first approach and retraction cycle. The structural changes corresponding to this intrinsic process are irreversible and lead to stable NC-AFM imaging conditions. In opposition to the picture used in literature, the Si(001)-type tip does not exhibit the so-called "two-dangling bond" feature as a bulklike termination suggests.