An Improved Performance and High Efficiency DJ III–V Tandem Solar Cell with the Impact of Quantum Tunneling

The work presented in this paper is part of the current context of research aimed at improving the performance of tandem DJ solar cells and understanding basic materials science based on III–V materials which has become a major field of studies in photovoltaics. This research`s main objective is to highlight the impact of band gap energy of materials used, in forming a quantum well structure (quantum confinement) as well as the correct choice of the tunnel junction (materials, thickness) on improving the electrical conversion efficiency and achieving optimum power of InGaP/GaAs DJ solar cell. In this regard, modeling a solar cell is the powerful tool that will allow us to link the characteristics of this cell with the properties of the material and the manufacturing technology to improve cell performance. To carry out our objectives, a numerical study presented by a numerical model of a GaInP/GaAs tandem cell built in Silvaco software showing the criteria of choosing the best junction tunnel (materials, thickness, doping..) which contribute to higher efficiency of DJ solar cell as well as to limit the various losses and therefore achieve a good compromise between cost and structure. This numerical model emphasizes the use of the III–V compound material of GaAs, ternary Ga1 – xInxP, (AlxGa1 – xAs and quaternary (AlxGa1–x)1 – yInyP), aiming at the potential of the band gap energy of these materials used on absorbing more photon energy from the optical source and then converting the optical energy on more electrical energy. The simulation results presented have enabled us to better understand the contours of the performance of tandem solar cells (single, dual junction) and to understand the need for their optimizations. These by the exploitation of the electrical and optical characteristics J–V, P–V which induced us to extract the photovoltaic parameters (Jsc, Voc, Pmax, FF, η) of tandem cells. Furhermore, the efficiency of carrier confinement is shown in quantum well active layer.