Performance investigation of Sb2S3 and Sb2Se3 earth abundant based thin film solar cells

Abstract

Recently, antimony sulfide (Sb2S3) and antimony selenide (Sb2Se3) materials have received a particular research attention as absorbers in hetero-junction thin film solar cells due to their high optical absorption, low cost, earth abundance, and non-toxic properties. In this work, we investigate numerically Sb2S3 and Sb2Se3 based solar cells and analyze their performance using SILVACO software. A simulation of absorber and buffer layers thickness, radiative recombination coefficient, doping densities in absorbent and buffer regions, defect in absorbent region and at buffer/absorber interface alongside with rear contact metal work function is effectuated in order to optimize these parameters. Absorber's optimal parameters are found to be 1 μm thickness, 10−9 cm3/s radiative recombination coefficient, 5 × 1016 cm−3 acceptor doping density, 1015 cm−3 defect density and 5 eV work function for Sb2S3 and 1.5 μm, 10−9 cm3/s, 1017 cm−3, 1015 cm−3 and 4.5 eV for Sb2Se3. Buffer layer optimal parameters are 20 nm thickness and 1020 cm−3 doping density for Sb2S3 based solar cell and 10 nm and 2 × 1020 cm−3 for Sb2Se3 one. Buffer/absorber interface optimal defect density is 1013 cm−3. PV structures with such optimal parameters give conversion efficiencies of 14.45 and 12.84% for Sb2S3 and Sb2Se3 based solar cells, respectively.