Researchers at the University of Copenhagen have grown nanowires with perfectly uniform electronic structure.

PhD student Peter Krogstrup, Niels Bohr Institute, in collaboration with a number of well-known researchers and the company SunFlake A/S, is behind the breakthrough. The new findings have recently been published in the journal NanoLetters.

Ultra clean means that the electronic structure is perfectly uniform throughout the nanowires, which is a very important part in obtaining nano-electronic devices of high performance. This is achieved by growing the wires without the use of a metal catalysis like gold, and at the same time having a perfect crystal of only one single structural phase which until now have been impossible for these types of nanowires.

- The ultra-clean wires are grown on a silicon substrate with an extremely thin layer of natural oxide. The element Gallium, which is a part of the nanowire material, reacts with the oxide and makes small holes in the oxide layer, and here the gallium collects into small droplets of a few nanometers in thickness. These droplets capture the element Arsenic – the other material in the nanowire and through a self-catalytic effect starts the growth of the nanowires without interference from other substances, explains Peter Krogstrup. The breakthrough is the result of a year’s work in connection with his PhD.

Read more at the Nano-Science Center website

Link to the article in Nano Letters