Application of the Concept of Lifetime‐Equivalent Defect Density in Defect Systems Comprising a Multitude of Defect Species

Abstract

The specific injection dependence of either excess carrier lifetime or lifetime‐equivalent defect density generally allows for the identification of a single defect species and the analysis of its properties. However, the presence of a multitude of defect species noticeably complicates this endeavor. A temporally different activation/deactivation dynamic of different defect species, as encountered in the context of light‐induced degradation phenomena in crystalline silicon solar cells, in combination with the distinct injection dependence of specific defect species can help to distinguish the involved defect species. Within this simulation‐based contribution, it is shown how injection‐dependent information can be used to reveal the presence of a second defect species in the context of light‐induced degradation and to distinguish clearly whether the formation of deep‐level defects in the bulk or a deterioration in the surface passivation quality is responsible for an observed degradation of effective excess carrier lifetime.