Abstract: A multijunction solar cell assembly and its method of manufacture including first and second discrete semiconductor body subassemblies, each semiconductor body subassembly including first, second and third lattice matched subcells; a graded interlayer adjacent to the third solar subcell and functioning as a lateral conduction layer; and a fourth solar subcell adjacent to said graded interlayer being lattice mismatched with respect to the third solar subcell; wherein the average band gap of all four cells is greater than 1.44 eV.

Abstract: A solar cell assembly for space application comprising a plurality of space-qualified solar cells and a support, the support comprising a conductive layer. The conductive layer is divided into a first conductive portion and a second conductive portion. Each space-qualified solar cell of the plurality of space-qualified solar cells comprising a front surface, a rear surface, and a first contact in correspondence with the rear surface. Each one of the plurality of space-qualified solar cells is placed on the first conductive portion with the first contact electrically connected to the first conductive portion so that the space-qualified solar cells are connected in parallel through the first conductive portion. A second contact of each space-qualified solar cell can be connected to the second conductive portion. The two conductive portions serve as bus bars of the space-qualified solar cell assembly.

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 and its method of fabrication, including an upper and a lower solar subcell each having an emitter layer and a base layer forming a photoelectric junction; a near infrared (NIR) wideband reflector layer disposed below the upper subcell and above the lower subcell for reflecting light in the spectral range of 900 to 1050 nm which represents unused and undesired solar energy and thereby reducing the overall solar energy absorptance in the solar cell and providing thermodynamic radiative cooling of the solar cell when deployed in space outside the atmosphere.

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 and its method of fabrication, having an upper first solar subcell composed of a semiconductor material including aluminum and 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; a first and second DBR structure adjacent to the third solar subcell; and a fourth solar subcell adjacent to the DBR structures and lattice matched with 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.

Abstract: A multijunction solar cell and its method of fabrication, having an upper first solar subcell composed of a semiconductor material including aluminum and 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; a first and second DBR structure adjacent to the third solar subcell; and a fourth solar subcell adjacent to the DBR structures and lattice matched with 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.

Abstract: A multijunction solar cell assembly and its method of manufacture including interconnected first and second discrete semiconductor body subassemblies disposed adjacent and parallel to each other, each semiconductor body subassembly including first top subcell, second (and possibly third) lattice matched middle subcells; a graded interlayer adjacent to the last middle solar subcell; and a bottom solar subcell adjacent to said graded interlayer being lattice mismatched with respect to the last middle solar subcell; wherein the interconnected subassemblies form at least a four junction solar cell by a series connection being formed between the bottom solar subcell in the first semiconductor body and the bottom solar subcell in the second semiconductor body.

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 assembly and its method of manufacture including first and second discrete semiconductor body subassemblies, each semiconductor body subassembly including first, second and third lattice matched subcells; a graded interlayer adjacent to the third solar subcell and functioning as a lateral conduction layer; and a fourth solar subcell adjacent to said graded interlayer being lattice mismatched with respect to the third solar subcell; wherein the average band gap of all four cells is greater than 1.44 eV.

Abstract: A method of manufacturing a multijunction 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; a graded interlayer adjacent to the third solar subcell; and a fourth solar subcell adjacent to said graded interlayer and composed of a semiconductor material having a fourth band gap smaller than the third band gap and being lattice mismatched with respect to the third solar subcell; wherein the fourth subcell has a direct bandgap of greater than 0.75 eV.

Abstract: A multijunction solar cell assembly and its method of manufacture including interconnected first and second discrete semiconductor body subassemblies disposed adjacent and parallel to each other, each semiconductor body subassembly including first top subcell, second (and possibly third) lattice matched middle subcells; a graded interlayer adjacent to the last middle solar subcell; and a bottom solar subcell adjacent to said graded interlayer being lattice mismatched with respect to the last middle solar subcell; wherein the interconnected subassemblies form at least a four junction solar cell by a series connection being formed between the bottom solar subcell in the first semiconductor body and the bottom solar subcell in the second semiconductor body.

Abstract: A multijunction solar cell and its method of fabrication, having an upper first solar subcell composed of a semiconductor material including aluminum and 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; a first and second DBR structure adjacent to the third solar subcell; and a fourth solar subcell adjacent to the DBR structures and lattice matched with 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.

Abstract: A multijunction solar cells that include one or more graded-index structures disposed directly above the growth substrate beneath a base layer of a solar subcells. In some embodiments, the graded-index reflector structure is constructed such that (i) at least a portion of light of a first spectral wavelength range that enters and passes through a solar cell above the graded-index reflector structure is reflected back into the solar subcell by the graded-index reflector structure; and (ii) at least a portion of light of a second spectral wavelength range that enters and passes through the solar cell above the graded-index reflector structure is transmitted through the graded-index reflector structure to layers disposed beneath the graded-index reflector structure. The second spectral wavelength range is composed of greater wavelengths than the wavelengths of the first spectral wavelength range.

Abstract: A multijunction solar cells that include one or more graded-index reflector structures disposed beneath a base layer of one or more solar subcells. The graded-index reflector structure is constructed such that (i) at least a portion of light of a first spectral wavelength range that enters and passes through a solar cell above the graded-index reflector structure is reflected back into the solar subcell by the graded-index reflector structure; and (ii) at least a portion of light of a second spectral wavelength range that enters and passes through the solar cell above the graded-index reflector structure is transmitted through the graded-index reflector structure to layers disposed beneath the graded-index reflector structure. The second spectral wavelength range is composed of greater wavelengths than the wavelengths of the first spectral wavelength range.