Scientists in the US have conducted a study to improve the control they can exert over the growth of nanoscale structures of semiconductor materials.
Researchers typically use trial and error to tune the reaction conditions to yield a certain type of structure, but now Zhong Lin Wang at Georgia Tech university has formalised the process using the optoelectronic material cadmium selenide.
“For the future of nanomanufacturing, we needed a systematic map to show the best conditions for producing these structures reproducibly with high yield,” said Wang.
“Our goal was to determine how to control the conditions to learn how to get close to 100 per cent yield of each structure.”
Wang explored 45 combinations of conditions and found growth of the nanostructures is primarily controlled by the pressure of nitrogen gas inside the reaction chamber and the temperature of the substrate on which the structures are deposited. The image shows a sample of nanoribbons, but ‘nanosaws’ and nanowires can also be produced by varying the conditions.
The work could help research using the structures in applications such as sensors and displays.
www.gatech.edu