Numerical modeling of CFTS-based thin film solar cells Effect of substrate and buffer laye

Abstract

Solar cells based on CFTS (Cu2FeSnS4) absorbers are made of earth-abundant low-cost, non-toxic and sustainable elements and are being extensively studied for improved efficiencies. CFTS compound is a semiconductor with a kesterite symmetrical structure. Three different buffer layers (CdS-SnS2-TiO2) in Mo/CTFS/buffers/FTO structure were analyzed. The influence of cell parameters such as the effect of Mo crystalline growth direction and work function, shunt resistance (RSh) and series resistance (RS) on the efficiency is evaluated using a one-dimensional solar cell capacitance simulator (SCAPS) software. In this work, promising optimized results had been achieved with the Mo [110] direction with 4.95 Φ/eV work function, TiO2 buffer layer with the conversion efficiency of 25.62%, fill factor 80.49 %, short-circuit current 33.87 mA/cm2 and open-circuit voltage 0.94 V. The above results will give imperative baselines and feasible directions for the fabrication of higher efficiency CFTS based photovoltaic cells.