摘要
A reasonably-thick GaNAs/GalnAs superlattice could be an option as a roughly 1 eV subcell to achieve high-effiCiency multi-junction solar cells on a lattice-matched Ge substrate. A detailed consideration of a high- efficiency design for a GaInP/GaAs/1 eV/Ge device is presented. Calculations have been done for this structure to obtain the confined energies of the electrons and holes by utilizing the Kronig-Penney model, as well as the absorption coefficient and thereby the external quantum efficiency. The effect of well layers, GaNAs or GaInAs, on the absorption and photocurrent density under the AM 1.5 condition is discussed in order to realize a requirement of current matching in the four-junction solar cells. The management of these considerations implies the feasibility of the GaNAs/GaInAs superlattice subcell design to improve the overall conversion efficiency of lattice matched GaInP/GaAs/1 eV/Ge cells.
A reasonably-thick GaNAs/GalnAs superlattice could be an option as a roughly 1 eV subcell to achieve high-effiCiency multi-junction solar cells on a lattice-matched Ge substrate. A detailed consideration of a high- efficiency design for a GaInP/GaAs/1 eV/Ge device is presented. Calculations have been done for this structure to obtain the confined energies of the electrons and holes by utilizing the Kronig-Penney model, as well as the absorption coefficient and thereby the external quantum efficiency. The effect of well layers, GaNAs or GaInAs, on the absorption and photocurrent density under the AM 1.5 condition is discussed in order to realize a requirement of current matching in the four-junction solar cells. The management of these considerations implies the feasibility of the GaNAs/GaInAs superlattice subcell design to improve the overall conversion efficiency of lattice matched GaInP/GaAs/1 eV/Ge cells.
基金
supported by the National Natural Science Foundation of China(No.61274134)
the International Cooperation Program of Suzhou
China(No.SH201215)