Raman spectroscopy and electrical properties of InAs nanowires with local oxidation enabled by substrate micro-trenches and laser irradiation

TL;DR

This study demonstrates localized oxidation of InAs nanowires using substrate micro-trenches and laser irradiation, enabling precise control of their electrical and structural properties for potential nanoelectronic applications.

Contribution

It introduces a novel method combining micro-trenches and laser irradiation for localized oxidation of nanowires, with detailed Raman and electrical characterization.

Findings

Localized oxidation confirmed by micro-Raman mapping.

Oxidized nanowires remain conductive with reduced conductance.

Numerical simulations match temperature profiles during oxidation.

Abstract

The thermal gradient along indium-arsenide nanowires was engineered by a combination of fabricated micro- trenches in the supporting substrate and focused laser irradiation. This allowed local control of thermally activated oxidation reactions of the nanowire on the scale of the diffraction limit. The locality of the oxidation was detected by micro-Raman mapping, and the results were found consistent with numerical simulations of the temperature profile. Applying the technique to nanowires in electrical devices the locally oxidized nanowires remained conducting with a lower conductance as expected for an effectively thinner conducting core.