Patent ID: 7812249

Claim:
A photovoltaic cell, comprising: a GaInP subcell comprising a disordered group-III sublattice base; a GaInAs subcell disposed below the GaInP subcell; and a semiconductor growth substrate disposed below the GaInAs subcell wherein said semiconductor growth substrate is lattice matched to said GaInP subcell, said semiconductor growth substrate comprising a surface misoriented from a (100) plane by an angle from about 8 degrees to about 40 degrees toward a nearest (111) plane, wherein said angle optionally consists of an angle of 15.8 degrees and said surface consists of a (115) surface orientation; wherein the angle produces a bandgap in the GaInP subcell such that the GaInP subcell and the GaInAs subcell exhibit substantially equal current densities, wherein a thickness of said GaInP subcell base is selected to provide current matching to said GaInAs subcell, said thickness corresponding to an increased amount of disorder in the sublattice of said base; and, wherein said semiconductor growth substrate orientation is combined with one or more alternative methods of inducing sublattice disorder in the GaInP sublattice to achieve a selected amount of said sublattice disorder in said GaInP sublattice.