Mechanism for room-temperature single-atom lateral manipulations on semiconductors using dynamic force microscopy.
Mechanism for room-temperature single-atom lateral manipulations on semiconductors using dynamic force microscopy.
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DOI：
10.1103/physrevlett.98.106104
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发表时间：
2007-03
影响因子：
8.6
通讯作者：
Y. Sugimoto;P. Jelínek;P. Pou;M. Abe;S. Morita;R. Pérez;O. Custance
中科院分区：
文献类型：
--
作者：
Y. Sugimoto;P. Jelínek;P. Pou;M. Abe;S. Morita;R. Pérez;O. Custance
报道了室温下空位对Si(111)-(7x7)表面内禀吸附原子的横向操纵。操纵过程中的地形信号结合力谱测量表明，这些操纵可以归因于所谓的拉动模式，并且在与操纵设定值相关的相对较低的短程力值下，Si原子是在吸引尖端-表面相互作用的区域被操纵的。第一性原理计算表明，针尖的存在导致了结构弛豫，削弱了吸附原子的表面键，表现为自然扩散势垒局部显著降低到相邻的吸附位置。在接近实验中测得的短程作用力附近，这些屏障被降低到接近允许在室温下进行热激活跳跃的极限。
Vacancy-mediated lateral manipulations of intrinsic adatoms of the Si(111)-(7x7) surface at room temperature are reported. The topographic signal during the manipulation combined with force spectroscopy measurements reveals that these manipulations can be ascribed to the so-called pulling mode, and that the Si adatoms were manipulated in the attractive tip-surface interaction regime at the relatively low short-range force value associated to the manipulation set point. First-principles calculations reveal that the presence of the tip induces structural relaxations that weaken the adatom surface bonds and manifests in a considerable local reduction of the natural diffusion barriers to adjacent adsorption positions. Close to the short-range forces measured in the experiments, these barriers are lowered near the limit that enables a thermally activated hopping at room temperature.