Department of Condensed Matter Physics, Braun Center for Submicron Research , Weizmann Institute of Science , Rehovot 76100 , Israel.
Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute , University of Copenhagen , 2100 Copenhagen , Denmark.
Nano Lett. 2018 Jul 11;18(7):4115-4122. doi: 10.1021/acs.nanolett.8b00853. Epub 2018 Jun 12.
We study the role of gold droplets in the initial stage of nanowire growth via the vapor-liquid-solid method. Apart from serving as a collections center for growth species, the gold droplets carry an additional crucial role that necessarily precedes the nanowire emergence, that is, they assist the nucleation of nanocraters with strongly faceted {111}B side walls. Only once these facets become sufficiently large and regular, the gold droplets start nucleating and guiding the growth of nanowires. We show that this dual role of the gold droplets can be detected and monitored by high-energy electron diffraction during growth. Moreover, gold-induced formation of craters and the onset of nanowires growth on the {111}B facets inside the craters are confirmed by the results of Monte Carlo simulations. The detailed insight into the growth mechanism of inclined nanowires will help to engineer new and complex nanowire-based device architectures.
我们通过汽相-液-固法研究了金滴在纳米线生长初始阶段的作用。除了作为生长物种的收集中心外，金滴还具有另一个关键作用，即在纳米线出现之前，它有助于具有强面心立方{111}B 侧壁的纳米坑的成核。只有当这些面变得足够大和规则时，金滴才开始成核并引导纳米线的生长。我们表明，在生长过程中，高能电子衍射可以检测和监测金滴的这种双重作用。此外，蒙特卡罗模拟的结果证实了金诱导的坑的形成以及坑内{111}B 面纳米线生长的开始。对倾斜纳米线生长机制的深入了解将有助于设计新型和复杂的基于纳米线的器件结构。
