Modeling of dual-junction tandem based on InGaP/GaAs heterojunction stacked on a Ge solar cell

Auteurs :  F. Bouzid, F. Pezzimenti, L. Dehimi, F.G. Della Corte, M. HADJAB, A. HADJ LARBI
Année : 2019
Domaine : Physique
Type : Communication
Conférence: 2nd International Conference on Photonics Research (Interphotonics-2019)
Résumé en PDF :  (résumé en pdf)
Fulltext en PDF :  (.pdf)
Mots clés : Analytical modeling, tandem solar cell, Spectral response, conversion efficiency

Résumé : 

In this work, an analytical model is used to describe the elctrical characteristics of a dual-junction tandem solar cell performing a conversion efficiency of 32.56% under air mass 1.5 global (AM1.5G) spectrum. The tandem structure consists of a thin heterojunction top cell made of indium gallium phosphide (InGaP) on gallium arsenide (GaAs), mechanically stacked on a relatively thick germanium (Ge) substrate which acts as bottom cell. In order to obtain the best performance of such a structure, we simulate for both the upper and lower sub-cell the current density-voltage, power density-voltage, and spectral response behaviours taking into account the doping-dependent transport parameters and a wide range of minority carrier surface recombination velocities.For the proposed tandem cell, our calculations predict that optimal photovoltaic (PV) parameters, namely the short-circuit current density (Jsc), open-circuit voltage (Voc), maximum power density (Pmax), and fill factor (FF) are Jsc= 28.25 mA/cm2, Voc= 1.24 V, Pmax = 31.64 mW/cm2, and FF = 89.95%, respectively. The present study could turn useful to support the design of high efficiency dual junction structures by investigating the role of different materials and physical parameters.