Improving the performance of ZnO/CdS/CZTS thin film solar cell by AMPS-1D numerical tool: effect of the absorber, buffer and window layer parameters

In this work, a simulation of non-toxic Cu₂ZnSnS₄ (CZTS) thin film solar cell with Al/ZnO/CdS/CZTS/Pd structure is performed utilizing the Analysis of Microelectronic and Photonic Structures (AMPS-1D) device simulator. Here, the effect of thickness, doping concentration, band gap energy of current ZnO/CdS/CZTS structures and the Mo, Si, Au and Ni back contact materials on the cell performances are investigated and evidenced. The best doping concentration (cm⁻³) is found to be around 10¹⁸, 10²⁰and 10¹⁹for CZTS, CdS, and ZnO layers respectively, and the most effective thicknesses (µm) are found to be approximately 6 for the absorber layer, 0.38 for the buffer layer, and 0.05 for the window layer. Additionally, the CZTS, CdS, and ZnO layers have the best band gap (eV) energies of 1.6, 2.57 and 3.3 respectively. The most results are power conversion efficiency (PCE) of 33.716%, with open circuit voltage (VOC) of1.241 V, short circuit current density (JSC) of 30.302 mA/cm² and FF of 89.7% are obtained with barrier height of 1.14 eV and Ni as back contact.