Hydrogen Reactions with Dopants and Impurities in Solar Silicon from First Principles

Abstract

A theoretical account of some of the most likely hydrogen‐related reactions with impurities in n‐ and p‐type solar‐grade silicon is presented. These include reactions with dopants and carbon, which are relevant in the context of lifetime degradation of silicon solar cells, most notably of light‐ and elevated temperature‐induced degradation of the cells. Among the problems addressed, a comparative study of acceptor‐enhanced dissociation of hydrogen molecules in B‐ and Ga‐doped material, their subsequent reaction steps toward formation of acceptor–hydrogen pairs, the proposal of mechanisms which explain the observed kinetics of photo‐/carrier‐induced dissociation of PH and CH pairs in n‐type Si, analysis of reactions involving direct interactions between molecules with P and C, and the assignment of several electron and hole traps with detailed atomistic‐ and wavefunction‐resolved models is highlighted.