Materials Engineering, The University of Queensland, St Lucia, Queensland 4072, Australia.
Nanotechnology. 2018 Nov 16;29(46):465601. doi: 10.1088/1361-6528/aadedd. Epub 2018 Sep 4.
Impurity addition is a crucial aspect for III-V nanowire growth. In this study, we demonstrated the effect of the Sn addition on GaAs nanowire growth by metal-organic chemical vapor deposition. With increasing the tetraethyltin flow rate, the nanowire axial growth was suppressed while the nanowire lateral growth was promoted, as well as planar defects were increased. Systematic electron microscopy characterizations suggested that the Sn addition tuned the catalyst composition, changed the vapor-solid-liquid surfaces energies and hindered the Ga atoms diffusion on nanowire sidewalls, which is responsible for the observed changes in morphology and structural quality of grown GaAs nanowires. This study contributes to understanding the role of impurity dopants on III-V nanowires growth, which will be of benefit for the design and fabrication of future nanowire-based devices.
杂质添加是 III-V 纳米线生长的一个关键方面。在这项研究中，我们通过金属有机化学气相沉积（MOCVD）展示了 Sn 添加对 GaAs 纳米线生长的影响。随着四乙基锡（TEtin）流速的增加，纳米线的轴向生长受到抑制，而纳米线的横向生长得到促进，同时平面缺陷也增加了。系统的电子显微镜表征表明，Sn 添加调整了催化剂的组成，改变了固-液-气界面的表面能，并阻碍了 Ga 原子在纳米线侧壁上的扩散，这是导致所观察到的 GaAs 纳米线形貌和结构质量变化的原因。这项研究有助于理解杂质掺杂剂在 III-V 纳米线生长中的作用，这将有助于未来基于纳米线的器件的设计和制造。
