Structural Investigation of Uniform Ensembles of Self-Catalyzed GaAs Nanowires Fabricated by a Lithography-Free Technique.

Nanoscale Res Lett

Optoelectronics Research Centre, Tampere University of Technology, Korkeakoulunkatu 3, FI-33720, Tampere, Finland.

Published: December 2017

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.

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Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5355414PMC
http://dx.doi.org/10.1186/s11671-017-1989-9DOI Listing

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