Thickness and Doping Optimization of CdS/CIGS P-i-N Photovoltaic Cell: Envisioned for Enhanced Conversion Efficiency

摘要

In this work, a high efficiency CdS/CIGS P-i-N solar cell has been proposed and delineated incorporating CIGS as an intrinsic layer and an immensely doped CIGS as a graded p-type layer. As ensued from our simulation, a conversion efficiency of 20.94% is attained with the coalescence of highly doped TCO layer (ZnO), n-type CdS window layer, CIGS as intrinsic layer and an ungraded (fixed doping concentration) CIGS absorber layer. It is construed that after introducing the graded (several doping concentrations) p-type absorber layer, the efficiency conspicuously amplified to a significant extent. At AM 1.5 solar radiation, the proposed graded cell structure yields an open circuit voltage ($V_{oc}$) of 0.726 V, a short circuit current density ($J_{sc}$) of 57.72 mAcm⁻², a maximum power density of 35.27 mWcm⁻² and a fill factor (FF) of 84%, conforming to an overall efficiency ($eta$) of 29.69%.