Dependence of quantum dot solar cell parameters on the number of quantum dot layers

We report the theoretical results of improved solar cell efficiency form InAs quantum dots (QDs) embedded in the intrinsic region of n-i-p GaAs structure. The effect of QD layers on the QD solar cell parameters is explained in detail. For QD layers of 250, we obtained a maximum efficiency of 27.4%. Increasing the number of layers beyond the optimum value resulted in the decrease of efficiency. The presence of InAs QD layers in the cell structure results in a significant rise of the short circuit current density from 33.4 mA/cm2 without InAs QD to 45.4 mA/cm2 in the presence of InAs QD. At the same time, the efficiency of the cell increased from 20.5% without InAs QD to 27.4% with InAs QD.