We demonstrated mainly some of the different parameters effects -as a function of temperature-as window layers, thickness, and doping of the various layers (emitter, base and BSF) on the performances of InGaP/GaAs solar cell. First, we have varied the molar fraction of different layers; their thickness and the doping of both emitters and bases. We have registered the result of each variation until obtaining optimal parameters. In a second stage, we have simulated the InGaP/GaAs cell without window layers which results in eta = 12.47% and eta = 22.14% for eliminating top and bottom windows respectively. Then, the elimination of layer BSFs(back surface field) on the back face of the considered cell causes a remarkable decrease in open circuit voltage Voc and output eta which reached 1.57 V and 11.95% respectively. In a last stage, we optimized and simulated the performances of the InGaP/GaAs dual-junction solar cell for its optimal parameters while varying its operation temperature from 300 K to 375 K with an increment of 25 degrees C using a virtual wafer fabrication TCAD Silvaco. The optimization at 300 K led to the following results Icc = 15.19 mA/cm(-2), Voc = 2.53 V, FF = 91.32% and eta = 25.43% which are close with those found in literature for In(1-x)Ga(x)P(x is molar fraction: x = 0.5). Therefore, we could determine the critical parameters of the cell and optimize its main parameters to obtain the highest performance for a dual junction solar cell. This work will pave the way with new prospects in the field of the photovoltaic. The structure simulation will simplify the manufacturing processes of solar cells; will thus reduce the costs while producing high outputs of photovoltaic conversion. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.