Assessing the defect responsible for LeTID: temperature- and injection-dependent lifetime spectroscopy

Abstract

Temperature- and injection-dependent lifetime spectroscopy (TIDLS) is employed to study the defect responsible for light- and elevated temperature-induced degradation (LeTID). In our previous analyses, titanium (Ti), molybdenum (Mo), and tungsten (W) were identified as potential candidates for LeTID. The addition of temperature dependence further constrains the defect parameters. Assuming constant defect parameters with temperature, we identify two possible sets of defect parameters: $k \pmb{=23.9+5.5}$ at $E_{\mathrm{t}}-E_{\mathrm{i}}=_{-}0.21\pm 0.06\mathrm{eV}$ and $k=23.5\pm 5.6$ at $E_{t-}E_{i}= \pmb{-0.10\pm0.07 \mathbf{eV}}$ . We consider our results in the context of published defect parameters identified by TIDLS in other LeTID samples, and we evaluate our results against reported defect parameter temperature dependencies for Ti and Mo. We conclude that Mo is most consistent with our measurements. Approaches beyond lifetime spectroscopy, including intentional contamination and chemical composition measurements, are required to determine the root cause of LeTID.