Effects of temperature on the ion-induced bending of germanium and silicon nanowires
Effects of temperature on the ion-induced bending of germanium and silicon nanowires
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DOI：
10.1088/2053-1591/aa7e05
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发表时间：
2017-07
影响因子：
2.3
通讯作者：
Osmane Camara;I. Hanif;M. Tunes;R. Harrison;G. Greaves;S. Donnelly;J. Hinks
中科院分区：
文献类型：
--
作者：
Osmane Camara;I. Hanif;M. Tunes;R. Harrison;G. Greaves;S. Donnelly;J. Hinks
纳米线可以使用离子束通过一种称为离子诱导弯曲（IIB）的现象来操纵。虽然IIB背后的机制仍然是争论的主题，但点缺陷或非晶化的积累通常被认为是可能的驱动机制。在文献中关于Ge和Si纳米线的IIB的先前结果已经表明，在照射之后，对准的纳米线是完全非晶的。最近报道的实验中，结晶种子被保存在否则非晶离子束弯曲的硅纳米线，然后促进固相外延生长（SPEG）在随后的退火。然而，离子诱导的纳米线的排列在SPEG过程中丢失。在这项工作中，在400 °C和500 °C的透射电子显微镜中分别对Ge和Si纳米线进行原位离子辐照，以抑制非晶化和点缺陷的积累。发现Ge和Si纳米线在辐照过程中发生弯曲，从而质疑在这种条件下基于损伤累积的机制的作用。这些实验首次展示了通过IIB重新排列单晶Ge和Si纳米线同时保持其晶体结构的简单方法。
Nanowires can be manipulated using an ion beam via a phenomenon known as ion-induced bending (IIB). While the mechanisms behind IIB are still the subject of debate, accumulation of point defects or amorphisation are often cited as possible driving mechanisms. Previous results in the literature on IIB of Ge and Si nanowires have shown that after irradiation the aligned nanowires are fully amorphous. Experiments were recently reported in which crystalline seeds were preserved in otherwise-amorphous ion-beam-bent Si nanowires which then facilitated solid-phase epitaxial growth (SPEG) during subsequent annealing. However, the ion-induced alignment of the nanowires was lost during the SPEG. In this work, in situ ion irradiations in a transmission electron microscope at 400 °C and 500 °C were performed on Ge and Si nanowires, respectively, to supress amorphisation and the build-up of point defects. Both the Ge and Si nanowires were found to bend during irradiation thus drawing into question the role of mechanisms based on damage accumulation under such conditions. These experiments demonstrate for the first time a simple way of realigning single-crystal Ge and Si nanowires via IIB whilst preserving their crystal structure.