Numerical Simulation of the Influence of an Sb layer on a Cu(In, Ga)Se₂ Solar Cells Performance

A comprehensive study of adding an antimony (Sb) layer on top of the Mo layer in a low cost CIGS solar cell is presented. It was found that adding Sb layer improves the solar cell efficiency which was attributed to the reduction of defects at the CdS/CIGS interface. To elucidate this phenomenon, numerical simulation is used to evaluate a CIGS thin film solar cell figures of merits with and without an Sb layer. The cell performance is evaluated by introducing defects at the interface CdS/CIGS. An improvement of the conversion efficiency from 12.08 to 13.6% is reached. The short circuit current density J_sc improved from 25.74 to 26.46 mAcm^-2, the open circuit voltage V_OC is reduced from 0.674 to 0.670 V and the fill factor FF increases from 69.57 to 77.13%. The calculated figures of merit are in good agreement with the measurement.