In this study the Silvaco TCAD software was used for modeling and simulation of two photovoltaic devices with ITO/TiO2/P3HT&PCBM/Ag and ITO/TiO2/CdS/P3HT&PCBM/Ag structures. All the simulation results were compared to experimental measurement data of fabricated solar cells (Chen and Li, 2013) [1]. The current density–voltage (J–V) characteristics and the external quantum efficiency (EQE) were simulated under AM1.5G illumination. The simulated photovoltaic parameters of solar cells, short-circuit current density of 5.80 mA/cm2, open circuit voltage of 0.61 V, the fill factor of 50% and the conversion efficiency 1.8% was obtained for the CdS QDSSC which are in good agreement with the experimental high record data. This improved efficiency is attributed to the increase in light absorption by inserting the CdS QD layer.
