InP/InGaAsP thin films based solar cells: Lattice mismatch impact on efficiency

Abstract

In this study, the optical proprieties and the performance of based indium gallium arsenide phosphide (InGaAsP) quaternary solar cells were investigated, the absorption and the bandgap energy of the InGaAsP quaternary epitaxy on the InP substrate were studied for different temperatures and pressure. Also, the lattice mismatch effect was introduced to investigate the change in the absorption coefficient and on the bandgap energy. We demonstrate that the physical parameters are more related to the variation of pressure than the temperature variation. An increase in absorption peaks is manifested by decreasing the pressure. This study allows us to explore the extrinsic conditions and the configuration of the deformations leading to the desired optoelectronic properties. Furthermore, the results found show that the rates of variation of the bandgap energy Eglh relating to the light holes, bandgap energy Eghh relating to the heavy holes, and of the bandgap energy Eg as a function of the pressure are more related to the rate of change of these energies as a function of temperature. The absorption coefficient α is important for materials with low bandgap energy, the peaks increase by increasing the temperature and by lowering the pressure. We exploited the results found to simulate a p-n junction cell based on the deformed InGaAsP alloy using the SCAPS software, we found that the deformation makes it possible to obtain a current Jsc equal to 47.03 mA/cm2, and it leads to a transition from the maximum current density to low voltages with conservation of its maximum value (36.03 mW/m2).