Thermally activated reorientation of di-interstitial defects in silicon

TL;DR

This paper introduces a di-interstitial defect model in silicon that explains the thermally activated reorientation of the P6 center, aligning ab initio calculations with experimental observations.

Contribution

The study presents a novel di-interstitial model for the P6 center, linking point defects to defect growth and explaining temperature-dependent symmetry transitions.

Findings

Activation energy of 0.5 eV matches experimental data

Di-interstitials serve as nuclei for defect growth

Model explains symmetry transition from C1h to D2d

Abstract

We propose a di-interstitial model for the P6 center commonly observed in ion implanted silicon. The di-interstitial structure and transition paths between different defect orientations can explain the thermally activated transition of the P6 center from low-temperature C1h to room-temperature D2d symmetry. The activation energy for the defect reorientation determined by ab initio calculations is 0.5 eV in agreement with the experiment. Our di-interstitial model establishes a link between point defects and extended defects, di-interstitials providing the nuclei for the growth.