The effect of quantum dot size, interdot distance and indium content on InxGa1−xN/GaN QD-IBSC

In_xGa_1-xN/GaN quantum dot intermediate band solar cell (QD-IBSC) is a promising candidate for the purpose of efficiency improvement of solar cells. In this work, the influences of interdot distance, quantum dot size and indium content of In_xGa_1-xN/GaN QD-IBSC on the position and width of the intermediate bands are investigated by solving Schrödinger equation using Kronig-Penney model. Finally the effects of intermediate band position and width on energy conversion efficiency are analyzed. The results reveal that the In_xGa_1-xN/GaN quantum dot intermediate band solar cell manifests much larger power conversion efficiency than that of conventional solar cells. The maximum efficiency occurs when the intermediate band is at the middle position of barrier material bandgap and bandwidth is wide enough to increase absorption of photons keeping carrier recombination negligible by tuning interdot distance, quantum dot size and indium content.