Koivusalo Eero, Hakkarainen Teemu, Guina Mircea
Optoelectronics Research Centre, Tampere University of Technology, Korkeakoulunkatu 3, FI-33720, Tampere, Finland.
Nanoscale Res Lett. 2017 Dec;12(1):192. doi: 10.1186/s11671-017-1989-9. Epub 2017 Mar 16.
Structural analysis of self-catalyzed GaAs nanowires (NWs) grown on lithography-free oxide patterns is described with insight on their growth kinetics. Statistical analysis of templates and NWs in different phases of the growth reveals extremely high-dimensional uniformity due to a combination of uniform nucleation sites, lack of secondary nucleation of NWs, and self-regulated growth under the effect of nucleation antibunching. Consequently, we observed the first evidence of sub-Poissonian GaAs NW length distributions. The high phase purity of the NWs is demonstrated using complementary transmission electron microscopy (TEM) and high-resolution X-ray diffractometry (HR-XRD). It is also shown that, while NWs are to a large extent defect-free with up to 2-μm-long twin-free zincblende segments, low-temperature micro-photoluminescence spectroscopy reveals that the proportion of structurally disordered sections can be detected from their spectral properties.
描述了在无光刻氧化物图案上生长的自催化砷化镓纳米线（NWs）的结构分析，并深入探讨了其生长动力学。对生长不同阶段的模板和纳米线进行统计分析表明，由于均匀的成核位点、纳米线二次成核的缺乏以及成核反聚束效应下的自调节生长，纳米线具有极高的尺寸均匀性。因此，我们首次观察到亚泊松分布的砷化镓纳米线长度分布的证据。利用互补透射电子显微镜（TEM）和高分辨率X射线衍射仪（HR-XRD）证明了纳米线的高相纯度。研究还表明，虽然纳米线在很大程度上无缺陷，具有长达2μm的无孪晶闪锌矿段，但低温微光致发光光谱显示，可以从其光谱特性中检测到结构无序部分的比例。
