Investigation of the ZnSe Layer, a Promising Buffer Layer Compared to the Reference CdS Buffer Layer

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Résumé

In a context where access to electricity is a key issue to improve the satisfaction of the basic needs of populations, such as health, education, communication, etc., the need to find available, abundant energy production sources of energy is more than an obligation. This is why researchers in the field of renewable energies in general and in particular of photovoltaic solar energy (PV) investigate on different materials to considerably improve the stability and the conversion yield of PV solar cells. Therefore, in addition to the numerical simulation, we analytically simulate our photovoltaic (PV) solar cell model based on assumptions that simplify the basic equations. Thus, we simulate the opto-electrical parameters that we compare with those obtained from the numerical simulation. Our investigations show that the open-circuit voltage (VOC) and the fill factor (FF) as a function of the thickness of the CIGS absorber simultaneous increase. Concerning the gap, we note an increase in FF for 1 < Eg < 1.3 eV and a decrease for Eg > 1.3 eV and VOC increases. The study carried out using alternative buffer layers shows good performances which are close to those of the standard buffer layer (CdS) and highlights the possibility of substituting the CdS buffer layer. The major advantage of these diapers comes from the fact that they are also non-toxic, the main raw material zinc is abundant and cheap. As for the space charge region (SCR), the study also shows good agreement between the numerical models and analytical models based on Equations (1) and (2). However, the analytical model presents a strategic issue which will allow us to further optimize the stability and opto-electrical performance of the CIGS-based solar cell using variables not accessible with the simulation software.

Mots-clés

PV Solar Energy, CIGS Solar Cell, Analytical Simulation, ZnSe Buffer Layer, Electrical Parameters