Numerical modelling and analysis of earth abundant Sb2S3 and Sb2Se3 based solar cells using SCAPS-1D

Antimony chalcogenides, Sb2S3 and Sb2Se3, are the promising candidates for next generation solar cells due to its non-toxicity, earth abundance, low cost and easy availability. In this work, Sb2S3 and Sb2Se3 hetero-junction solar cells are modeled, numerically analyzed and compared by the SCAPS (Solar Cell Capacitance Simulator) software. Initial simulation for configuration optimization was done in detail for absorber layer thickness, buffer layer thickness, acceptor density, radiative recombination coefficient, series-shunt resistance, defect density and the work function of the back contact. A detailed analysis of the junction characteristics like carrier generation and recombination, built-in electric field and capacitance-voltage (C-V) study was also done in the second stage to determine the carrier lifetime, depletion width, built-in potential and doping density. The present study shows that, the optimum thickness for Sb2S3 absorber layer is 2.5 μm and for Sb2Se3 absorber layer is 2 μm to achieve the best efficiency. The buffer layer optimum thickness for Sb2S3 and Sb2Se3 solar cell is in the range of 50 nm to 60 nm. The optimum series and shunt resistance for Sb2S3 and Sb2Se3 based solar cell device is coming in the range of 3–5 Ω-cm2 and 300 - 450 Ω-cm2 respectively. It is also found that metal having work function 5eV or more is better to be used as an electrode in Sb2S3 or Sb2Se3 based solar cell. A maximum efficiency of 9.51% and 12.62% is achieved after optimizing different parameters for the Sb2S3 and Sb2Se3 solar cells respectively.