Impacts of Indirect Wider Bandgap of Non-Toxic AlxGa1-xAs Buffer in Copper-Indium-Gallium-Diselenide Photovoltaic Cell

• Main Authors: Sadia Islam Shachi, Nusrat Jahan, Ali Newaz Bahar, Md. Asaduzzaman
• Format: Article
• Language: English
• Published: KeAi Communications Co., Ltd. 2020-01-01
• Series: Solid State Electronics Letters
• Subjects: Indirect bandgap; Cd-free; Al0.9Ga0.1 buffer layer; critical thickness; CIGS solar cell
• Online Access: http://www.sciencedirect.com/science/article/pii/S2589208820300181
• ISSN: 2589-2088

A numerical simulation and substantiation have been accomplished to analyze the impact of Al0.9Ga0.1As alloy composite buffer layer band gap and thickness, absorber layer thickness on a ZnO:Al/i-ZnO/Al0.9Ga0.1As/CIGS/Mo/SLG structured non-toxic Cd-free CIGS photovoltaic cell. In this study, the cell output attributes including efficiency (η) and collection efficiency (ηc) have been optimized through short circuit current density (Jsc), open-circuit voltage (Voc) and fill factor (FF) optimization. Our study has been concluded with the maximum efficiency of 24.32% with Voc = 839.76 mV, Jsc = 36.21mA/cm2 and FF=76.96%, ηc = 83.16%. This enhanced efficiency is optimized by determining the bandgap of the buffer through altering the Al concentration to transit it from direct bandgap material to an indirect one. The thickness of the absorber on system performance is also investigated, and its extent is found in between 2 µm to 3 µm.