Modeling of CIGS single–junction solar cell using multiple quantum well structure with enhanced efficiency

Multiple quantum wells (MQWs) are incorporated in the standard CIGS single–junction solar cell. The aim of the present study is to enhance the efficiency of the solar cell by increasing the short circuit current (Jsc) while preserving the open circuit voltage (Voc). The simulation process was initiated by modeling of a standard CIGS solar cell followed by optimization of the thickness for different layers to achieve the highest efficiency. Then, using k.p and QWELL models in ATLAS Silvaco software, a single QW in the cell with different widths is modelled. After that, the concentration of Ga is varied for bandgap tuning. The modelled solar cell with optimized Ga concentration and QW width, showed higher output values than the conventional sample. Addition of more QWs resulted in higher Jsc and the efficiency enhancement. An excellent efficiency of 24.23% along with privileged output parameters were attained for the single–junction CIGS solar cell possessing six back–to–back QWs.