Device Performance Enhancement Using CTSe/CTSSe Bilayer Structure: A Numerical Analysis

The proposed work focuses on the performance assessment of a stacked bilayer structure, copper tin selenide (CTSe) and copper tin sulphur selenide (CTSSe) based thin film solar cell which are novel materials and has been investigated numerically using wx-AMPS software. Depending on the device structure, different optimizations have been carried out and the impact of top and bottom absorber layer thickness, carrier concentration and its defect density on the performance of CTSe/CTSSe based bilayer thin film solar cell (TFSC) was studied. The structure shows efficiency (
$\eta$
) of 14.23 % with open circuit voltage (Voc) as 0.74 V, short circuit current (Jsc) of 22.93 mA/cm
²
and fill factor (FF) of 84.50 % using molybdenum as back metal contact. Effect of using different back metal contact replacing molybdenum has been also studied and simulated with the proposed structure for which we got the highest efficiency of 18.24 % with Voc as 0.91 V, Jsc of 22.96 mA/cm
²
and FF of 86.89%.