Abstract: A multijunction solar cell including a metamorphic layer, and particularly the design and specification of the composition, lattice constant, and band gaps of various layers above the metamorphic layer in order to achieve reduction in “bowing” of the semiconductor wafer caused by the lattice mismatch of layers associated with the metamorphic layer.

Abstract: A multijunction solar cell including a metamorphic layer, and particularly the design and specification of the composition, lattice constant, and band gaps of various layers above the metamorphic layer in order to achieve reduction in “bowing” of the semiconductor wafer caused by the lattice mismatch of layers associated with the metamorphic layer.

Abstract: A multijunction solar cell including a metamorphic layer, and particularly the design and specification of the composition, lattice constant, and band gaps of various layers above the metamorphic layer in order to achieve reduction in “bowing” of the semiconductor wafer caused by the lattice mismatch of layers associated with the metamorphic layer.

Abstract: The present disclosure provides a multijunction solar cell comprising: an upper solar subcell having an indirect band gap semiconductor emitter layer composed of greater than 0.7 but less than 1.0 mole fraction aluminum and a base layer, the emitter layer and the base layer forming a heterojunction solar subcell; and a lower solar subcell disposed beneath the upper solar subcell, wherein the lower solar subcell has an emitter layer and a base layer forming a photoelectric junction. In some embodiments, the emitter layer of the upper solar subcell is an n-type AlxGa1-xAs layer with 0.7<x<1.0 and having a band gap of greater than 1.85 eV.

Abstract: A solar cell comprising a bulk germanium silicon growth substrate; a diffused photoactive junction in the germanium silicon substrate; and a sequence of subcells grown over the substrate, with the first grown subcell either being lattice matched or lattice mis-matched to the growth substrate.

Abstract: A multijunction solar cell including a metamorphic layer, and particularly the design and specification of the composition, lattice constant, and band gaps of various layers above the metamorphic layer in order to achieve reduction in “bowing” of the semiconductor wafer caused by the lattice mismatch of layers associated with the metamorphic layer.

Abstract: A solar cell comprising a bulk germanium silicon growth substrate; a diffused photoactive junction in the germanium silicon substrate; and a sequence of subcells grown over the substrate, with the first grown subcell either being lattice matched or lattice mis-matched to the growth substrate.

Abstract: A four junction solar cell having an upper first solar subcell composed of a semiconductor material having a first band gap; a second solar subcell adjacent to said first solar subcell and composed of a semiconductor material having a second band gap smaller than the first band gap and being lattice matched with the upper first solar subcell; a third solar subcell adjacent to said second solar subcell and composed of a semiconductor material having a third band gap smaller than the second band gap and being lattice matched with the second solar subcell; and a fourth solar subcell adjacent to and lattice mismatched from said third solar subcell and composed of a semiconductor material having a fourth band gap smaller than the third band gap; wherein the fourth subcell has a direct bandgap of greater than 0.75 eV, and the average band gap of the solar cell is equal to or greater than 1.35 eV.

Abstract: A solar cell comprising a bulk germanium silicon growth substrate; a diffused photoactive junction in the germanium silicon substrate; and a sequence of subcells grown over the substrate, with the first grown subcell either being lattice matched or lattice mis-matched to the growth substrate.

Abstract: A solar cell comprising a bulk germanium silicon growth substrate; a diffused photoactive junction in the germanium silicon substrate; and a sequence of subcells grown over the substrate, with the first grown subcell either being lattice matched or lattice mis-matched to the growth substrate.