09:15 〜 09:30
▲
[23a-E106-2] Impact of quasi-fermi level splitting and sub-bandgap absorptivity on the VOC loss in
CIGS solar cells
キーワード:CIGS solar cells, Quasi-fermi level splitting, Open-circuit voltage loss
The Shockley and Queisser principle of detailed balance (SQ model) between absorbed and emitted radiative fluxes from a photovoltaic absorber is the most common method used to evaluate the loss mechanisms in solar cells. The model assumed a step-like absorption coefficient thus neglecting the effect of band tailing for material with non-abrupt band edges wherein the electron-hole quasi fermi level splitting (QFLS) can modify both the absorption and emission spectrum. Here, we analyze the impact of the QFLS and sub-bandgap absorptivity on the VOC loss mechanism in CIGS solar cell devices using full-spectrum fitting of the photoluminescence (PL) emission.