Inhomogeneous Si-doping of gold-seeded InAs nanowires grown by molecular beam epitaxy

TL;DR

This study explores in-situ silicon doping of InAs nanowires grown via molecular beam epitaxy, revealing inhomogeneous doping profiles and their effects on nanowire growth and electrical properties.

Contribution

It demonstrates the inhomogeneous Si doping in InAs nanowires and its impact on growth dynamics and electrical characteristics, providing insights into doping mechanisms during MBE growth.

Findings

Electron density increases with Si flux.

Doping is inhomogeneous along the nanowire length.

Si doping influences lateral growth without significant tapering.

Abstract

We have investigated in-situ Si doping of InAs nanowires grown by molecular beam epitaxy from gold seeds. The effectiveness of n-type doping is confirmed by electrical measurements showing an increase of the electron density with the Si flux. We also observe an increase of the electron density along the nanowires from the tip to the base, attributed to the dopant incorporation on the nanowire facets whereas no detectable incorporation occurs through the seed. Furthermore the Si incorporation strongly influences the lateral growth of the nanowires without giving rise to significant tapering, revealing the complex interplay between axial and lateral growth.