TITLE:
Performance Enhancement of CZTS Solar Cell with CuSbS2 Back Surface Field: A Numerical Simulation Approach
AUTHORS:
Md. Ferdous Wahid, Nowshad Ahmed, Md. Shahriar Rahman, Abdullah Al Mamun, Md. Nuralam Howlader, Md. Motiur Rahman Tareq
KEYWORDS:
Solar Cell, CZTS, BSF, Defect Density, Doping Concentration, SCAPS-1D
JOURNAL NAME:
Engineering,
Vol.15 No.9,
September
13,
2023
ABSTRACT: Copper Zinc Tin Sulfide (CZTS) solar cell (SC) has garnered significant
attention from researchers in recent years owing to its affordability, less
toxic earth abundant constituents, remarkable conversion efficiency and
promising prospects for the bulk manufacture of thin film solar cells. Moreover, CZTS exhibits a high
absorption coefficient and possesses an optimal adjustable direct band gap,
making it a promising candidate for various photovoltaic applications. Hence, in this study, a new
configuration (CuSbS2/CZTS/CdS/i-ZnO/ Al: ZnO) is introduced for CZTS SC, which was simulated using SCAPS-1D. The
utilization of CuSbS2 as the back surface field (BSF) and CdS as the
buffer layer was investigated to enhance the performance of CZTS SC. Moreover,
a comparative numerical analysis was carried out to contrast the SC configurations
of CZTS/CdS/i-ZnO/Al: ZnO and CuSbS2/CZTS/CdS/i-ZnO/Al: ZnO. In this study, the impact on SC parameters such as open circuit
voltage (Voc), short- circuit
current density (Jsc), Fill-factor (FF), and Power Conversion
Efficiency (PCE) by varying thickness,
doping density, defect density of absorber and buffer layer, thickness and
doping density of BSF, and operating temperature have been thoroughly investigated. The optimum structure consists
of i-ZnO and Al: ZnO for the window layer, CdS for the buffer layer, CZTS for
the absorber layer, and BSF layers with thicknesses of 50 nm, 200 nm, 50 nm,
2000 nm, and 50 nm, respectively. The designed SC with a BSF layer had a PCE of
28.76%, JSC of 32.53 mA/cm2, Voc of 1.01233 V,
and FF of 87.35%. The structure without a BSF layer has a PCE of 24.21%, Voc of 0.898 V, JSC of 31.56 mA/cm2, and FF of 85.32%.
Furthermore, an analysis of temperature, quantum efficiency (QE), C- V characteristics and the J-V curve was conducted, revealing the potential of CuSbS2 as a BSF and CdS as a
buffer layer in high-performance, cost-effective CZTS SC
designs.