Simulation d’une cellule solaire en couche mince à base de Cuivre-Zinc-Étain Sulfure/Séléniure Cu2ZnSn(S,Se)4

Abstract

The aim of this work is to do a simulation of a Cu2ZnSn(S,Se)4 thin film photovoltaic solar cell in order to link the characteristics of this cell to the materials parameters in order to improve its performances. It is found that, to spread the space charge zone on both layers of the junction, the doping concentrations of the CdS window layer and the Cu2ZnSn(S,Se)4 absorber layer should be in order of 1015cm-3 and 1014cm-3 respectively. Furthermore, the cell performances are almost invariables while the thickness of the window layer is equal to or less than the width of the space charge zone. But, as soon as it exceeds this width, a slight reduction in these performances is observed. However, the absorber layer has an optimal value of the thickness in the order of 3μm, which equal to the width of the depletion zone of its side that corresponds to the values of doping concentrations given above. An optimum value of the absorber gap of around 1.5 eV is obtained. This value is the compromise between the decreases of the short circuit current density and the increases of the open circuit voltage with the increases of the gap. This leads to a maximum cell efficiency of 12.3%.