Phosphorus-Controlled Nanoepitaxy in the Asymmetric Growth of GaAs-InP Core-Shell Bent Nanowires

TL;DR

This paper demonstrates phosphorus-controlled nanoepitaxy in bent GaAs-InP nanowires, revealing growth regimes and enabling the fabrication of complex nanowire structures for advanced device applications.

Contribution

It introduces a novel phosphorus-controlled nanoepitaxial growth method for bent nanowires, elucidating growth regimes and enabling complex nanostructure fabrication.

Findings

Identification of indium-diffusion limited and phosphorous-limited growth regimes

Controlled synthesis of connected nanowire pairs and nano-arches

Insights into the role of adatom diffusion and flux shadowing in nanoepitaxy

Abstract

Breakthroughs extending nanostructure engineering beyond what is possible with current fabrication techniques will be crucial for enabling next-generation nanotechnologies. Nanoepitaxy of strain-engineered bent nanowire heterostructures presents a promising platform for realizing bottom-up and scalable fabrication of nanowire devices. The synthesis of these structures requires the selective asymmetric deposition of lattice-mismatched shells-a complex growth process which is not well understood. We present the nanoepitaxial growth of GaAs-InP core-shell bent nanowires and connecting nanowire pairs to form nano-arches. Compositional analysis of nanowire cross-sections reveals the critical role of adatom diffusion in the nanoepitaxial growth process, which leads to two distinct growth regimes: indium-diffusion limited growth and phosphorous-limited growth. The highly controllable phosphorous-limited growth mode is employed to synthesize connected nanowire pairs and quantify the role of flux shadowing on the shell growth process. These results provide important insight into three-dimensional nanoepitaxy and enable new possibilities for nanowire device fabrication.