Strain Effects on Auger-Meitner Recombination in Silicon

TL;DR

This study investigates how biaxial strain influences Auger-Meitner recombination in silicon, revealing that strain generally increases recombination rates but can suppress specific processes, thereby affecting carrier lifetimes and device efficiency.

Contribution

It provides first-principles insights into strain-dependent AMR rates and phonon contributions, highlighting potential for strain engineering in silicon device optimization.

Findings

Most AMR processes have increased rates under strain.

Tensile strain suppresses certain hole-electron recombination processes by 38%.

Strain enhances anisotropy in phonon-assisted mechanisms.

Abstract

We study the effects of compressive and tensile biaxial strain on direct and phonon-assisted Auger-Meitner recombination (AMR) in silicon using first-principles calculations. We find that the application of strain has a non-trivial effect on the AMR rate. For most AMR processes, the application of strain increases the AMR rate. However, the recombination rate for the AMR process involving two holes and one electron is suppressed by 38% under tensile strain. We further analyze the specific phonon contributions that mediate the phonon-assisted AMR mechanism, demonstrating the increased anisotropy under strain. Our results indicate that the application of tensile strain increases the lifetime of minority electron carriers in p-type silicon, and can be leveraged to improve the efficiency of silicon devices.