Efficiency enhacement of CIGS/CIGS tandem solar cell by ZnSe as buffer layer and optimizing the thickness of the absorber layer

In this paper, we investigated the numerical simulation of the CIGS/CIGS tandem solae cells using the two-dimensional Device simulator Silvaco-Atlas under standard AM۱.۵G.we considered the CIGS absorbing layer thicknwss , type of buffer layer and varying the electrode metal as key parameters to optimize the performance of the CIGS/CIGS tandem solar cell. The electrical parameters of the best CIGS/CIGS tandem solar cell structure were a short circuit current density (Jsc) of ۱۰۹ mA/cm^۲ , an open-circuit voltage (Voc) of ۱.۸V , a Fill factor (FF) of ۱۰۰% , and the conversion efficiency (ŋ) of ۳۹.۷۲%.