Influence of deep level defects on the performance of crystalline silicon solar cells: Experimental and simulation study

Abstract

Introduction of deep level defects during thermal diffusion of phosphorous (P) in silicon (Si) using spin-on-doping (SOD) from phosphosilicate glass (PSG) was studied using deep level transient spectroscopy (DLTS). The structure was utilized as a solar cell and defect-induced-degradation of the cell efficiency was studied and modeled. The light current–voltage (LIV) measurements performed on as-fabricated solar cell yielded open circuit voltage, short-circuit current density, fill factor ( FF) and efficiency to be 540 mV, 24 mA/cm 2, 40% and 5%, respectively. Whilst the simulation of the similar solar cell using AFORS-HET software revealed significantly higher data than the experimental ones. However, by including three deep level defects H 1–H 3 (holes) having activation energies (eV) 0.23, 0.33 and 0.41 in the modeled solar cell, the simulated results were observed in remarkably good agreement with experimental data. Our DLTS measurements practically witnessed H 1–H 3 defect levels in p-layer of the cell.