Understanding of the Retarded Oxidation Effects in Silicon Nanostructures

TL;DR

This paper investigates the complex retarded oxidation behavior in silicon nanostructures, modeling the mechanical stress and oxidation kinetics to explain the phenomena observed during wet thermal oxidation.

Contribution

It presents a novel model that explains retarded oxidation in silicon nanostructures by incorporating stress relaxation effects and predicts oxidation behavior at nanometer scales.

Findings

Model accurately describes oxidation kinetics of silicon nanowires.

Predicts realistic stress levels at the Si/SiO2 interface.

Explains the retarded oxidation phenomenon in various nanostructures.

Abstract

In-depth understanding of the retarded oxidation phenomenon observed during the oxidation of silicon nanostructures is proposed. The wet thermal oxidation of various silicon nanostructures such as nanobeams, concave/convex nanorings and nanowires exhibits an extremely different and complex behavior. Such effects have been investigated by the modeling of the mechanical stress generated during the oxidation process explaining the retarded regime. The model describes the oxidation kinetics of silicon nanowires down to a few nanometers while predicting reasonable and physical stress levels at the Si/SiO$_{2}$ interface by correctly taking into account the relaxation effects in silicon oxide through plastic flow.