2.0-2.1 eV GaxIn1−xP solar cells grown on relaxed GaAsP step grades

A high quality solar cell with a bandgap in the range of 2.0-2.1 eV may enable the development of four- and five-junction solar cells for terrestrial and space applications. In this paper we describe a set of 2.0-2.1 eV nVp solar cells fabricated from Ga x ln 1-x P and grown on compositional step-grades of GaAs 1-y P y , on GaAs substrates. Cells were grown by atmospheric pressure organometallic vapor phase epitaxy. The tensile grades were designed to achieve nearly complete relaxation of the active layers, and the in-situ stress as monitored during growth showed a residual tensile stress of