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

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. The thermodynamics of several reactions involving atomic and molecular hydrogen with group-III acceptors in silicon has been investigated theoretically. The results offer a first-principles-level account of thermally and carrier-activated processes relevant to light- and elevated temperature-induced degradation of Si-based solar cells.image (c) 2023 WILEY-VCH GmbH