Recombination Activity and Impact of the Boron--Oxygen-Related Defect in Compensated N-Type Silicon

摘要

In this paper, we present experimental data regarding the recombination activity and concentration of the boron--oxygen complex in compensated n-type silicon, doped with phosphorus and boron, when subjected to illumination. Unlike the data of Bothe $et al.$ in n-type silicon compensated with thermal donors, our results suggest the dominant defect level in our doping range to be a shallow level ($E_C$--$E_T$ = 0.15 eV), with a capture cross-section ratio $sigma_n$/$sigma_p$ of around 0.006, suggesting a negatively charged center. We also confirm previous results showing an increasing defect density with bias light intensity. Due to the strong lifetime reduction observed, we suggest that this material might not be suited to make high-efficiency n-type solar cells, unless practical strategies to reduce the defect concentration can be developed.