[Zurück]

S. Barth, J. Holmes:
"Growth Of Germanium Nanowires By Solid-Phase Seeding: Opportunities And Limitations";
Vortrag: 14. Österreichische Chemietage, Johannes Kepler Universität, Linz; 26.09.2011 - 29.09.2011; in: "14. Österreichische Chemietage - Program", (2011), Paper-Nr. OP-42, 1 S.

One-dimensional (1D) semiconductor nano-architectures with tunable morphologies, dimensions, crystallographic phases and orientation are of tremendous interest for a broad range of applications. Metal-seeded growth of 1D semiconductor nanostructures is still a very active field of research, despite the huge progress which has been made in understanding this fundamental phenomenon. However the transfer of crystallographic information from a nanoparticle seed to a growing nanowire has not been described in the literature. We investigated the formation of Ge nanowires using solid metal growth promoters in a supercritical fluid based process. The theoretical requirements for transferring defects from nanoparticle seeds to growing semiconductor nanowires were defined, and we describe why specific metal nanoparticles are ideal candidates for this purpose (alloying, available physico-chemical data etc.).
Significantly, under certain reaction conditions {111} stacking faults in the noble metal seeds can be directly transferred to a high percentage of <112> oriented Ge nanowires, in the form of radial twins in the semiconductor crystals. We will detail the influence of solid growth seeds on the crystal quality of Ge nanowires and demonstrate size-selective growth in the sub-20 nm diameter regime. Controlled defect transfer from nanoparticles to nanowires could open up the possibility of engineering 1D nanostructures with new and tuneable physical properties.