Optimization of Nanostructured Kesterite Thin Film Solar Cell Performance Enhancement Using Defect Engineering and Multiple Quantum Wells

Abstract

Kesterite materials have recently come to light as an alternative material for CIGS thin film solar cell with the potential to be used as a p-type absorber layer. They are earth-friendly, less-toxicity and cost-effective thin film solar cell. It possesses exceptional optical properties, including a direct band gap and an absorption coefficient. newlineThe Shockley-Queisser limit states that with a band gap of 1.5 eV (CZTS) could achieve an efficiency of 28%, while a solar cell with a low band gap of 1.0eV (CZTSe) can potentially achieve an efficiency of 30%. However, CZTS or CZTSe solar cell has not yet achieved a conversion efficiency of 28%. Low carrier lifetime, interface trap, bulk trap, deeper acceptor defects (CuZn), deeper donor defects (ZnCu), point defects and grain boundaries are some of the issues that reduce the overall efficiency of device. High open circuit voltage (VOC) deficiencies were also claimed to be the cause of the efficiency constraint. Several solution pathways have been investigated to overcome the existing efficiency 12.6% constraint newline