Nano Lett. http://doi.org/43t (2015)

Credit: AMERICAN CHEMICAL SOCIETY

Metal seed particles have been regularly used in the fabrication of semiconductor nanowires, as they provide a means to control the nanowire properties, such as growth rate and geometry. However, the incompatibility of materials commonly used (such as Au), with conventional processing techniques, and the need for control over desirable doping profiles of the nanowires, have led to the investigation of alternative materials. Kimberly Dick and colleagues now explore the potential of Sn as a seed particle for GaAs nanowires, grown by metal–organic vapour phase epitaxy. The nanowires are found to be free of stacking defects, while behaving similarly to highly doped p–n junctions (Esaki diodes). The doping is likely to be due to the incorporation of Sn in the core of the nanowire. Achieving such characteristics during a single-step growth process, without additional doping is rather unexpected. This work highlights the potential of alternative elements as metal seed particles for the fabrication of nanowires with new material properties.