Abstract: An automated method causes a terrestrial solar cell array to track the sun. The solar cell system includes motors that adjust a position of the array along different respective axes with respect to the sun, wherein a first motor adjusts the inclination angle of the array relative to the surface of the earth and a second motor rotates the array about an axis substantially perpendicular to that surface. The method includes (a) using a software algorithm to predict a position of the sun at a future time; (b) using a computer model to determine respective positions for the motors corresponding to the solar cell array being substantially aligned with the sun at the future time; and (c) activating and operating the motors at respective particular speeds so that at the future time the solar cell array is substantially aligned with the sun.

Abstract: A method of manufacturing a mounted solar cell by providing a metallic flexible film having a predetermined coefficient of thermal expansion; and attaching the semiconductor solar cell to the metallic film, the coefficient of thermal expansion of the semiconductor body closely matching the predetermined coefficient of thermal expansion of the metallic film.

Abstract: A solar cell including a semiconductor body with a multijunction solar cell and an integral bypass diode, and a pair of vias extending between the upper and lower surfaces, forming determined on the lower surface and electrically coupling the anode of the bypass diode with the conductive grid on the upper surface.

Abstract: A solar cell receiver comprising a solar cell having one or more III-V compound semiconductor layers, a diode coupled in parallel with the solar cell and operable to be forward-biased in instances when the solar cell is not generating above a threshold voltage, a coating substantially encapsulating the diode, an undercoating that substantially eliminates any air gap between the anode and cathode of the diode, and a connector adapted to couple to other solar cell receivers.

Abstract: A process for selectively freeing an epitaxial layer from a single crystal substrate upon which it was grown, by providing a first substrate; depositing a separation layer on the first substrate; depositing on the separation layer a sequence of layers of semiconductor material forming a solar cell; mounting and bonding a thin flexible support having a coefficient of thermal expansion substantially greater than that of the adjacent semiconductor material on top of the sequence of layers at an elevated temperature; and etching the separation layer while the temperature of the support and layers of semiconductor material decrease, so that the support and the attached layer curls away from the first substrate in view of their differences in coefficient of thermal expansion, so as to remove the epitaxial layer from the substrate.

Abstract: A method of forming a multifunction solar cell including an upper subcell, a middle subcell, and a lower subcell by providing a first substrate for the epitaxial growth of semiconductor material; forming a first solar subcell on the substrate having a first band gap; forming a second solar subcell over the first solar subcell having a second band gap smaller than the first band gap; forming a graded interlayer over the second subcell, the graded interlayer having a third band gap greater than the second band gap; forming a third solar subcell over the graded interlayer having a fourth band gap smaller than the second band gap such that the third subcell is lattice mismatched with respect to the second subcell; attaching a surrogate second substrate over the third solar subcell and removing the first substrate; and etching a first trough around the periphery of the solar cell to the surrogate second substrate so as to form a mesa structure on the surrogate second substrate and facilitate the removal of said so

Abstract: A solar cell module to convert light to electricity. The module may include a housing with a first side and an opposing spaced-apart second side. A plurality of lenses may be positioned on the first side of the housing, and a plurality of solar cell receivers may be positioned on the second side of the housing. Each of the plurality of solar cell receivers may include a III-V compound semiconductor multifunction solar cell. Each may also include a bypass diode coupled with the solar cell. At least one optical element may be positioned above the solar cell to guide the light from one of the lenses onto the solar cell. Each of said solar cell receivers may be disposed in an optical path of one of the lenses. The lens and the at least one optical element may concentrate the light onto the respective solar cell by a factor of 1000 or more to generate in excess of 25 watts of peak power.

Abstract: A method of forming a multifunction solar cell including an upper subcell, a middle subcell, and a lower subcell by providing a substrate for the epitaxial growth of semiconductor material; forming a first solar subcell on the substrate having a first band gap; forming a second solar subcell over the first solar subcell having a second band gap smaller than the first band gap; forming a graded interlayer over the second subcell, the graded interlayer having a third band gap greater than the second band gap; forming a third solar subcell over the graded interlayer having a fourth band gap smaller than the second band gap such that the third subcell is lattice mismatched with respect to the second subcell; and forming a contact composed of a sequence of layers over the first subcell at a temperature of 280° C. or less and having a contact resistance of less than 5×10?4 ohms-cm2.

Abstract: Dopant diffusion into semiconductor material is controlled during fabrication of a semiconductor structure by depositing a nucleation layer over a first layer of the semiconductor structure and depositing a device layer containing the dopant over the nucleation layer. The nucleation layer serves as a diffusion barrier by limiting in depth the diffusion of the dopant into the first layer. The dopant can include arsenic (As).

Abstract: A multijunction solar cell including an upper first solar subcell having a first band gap; a middle second solar subcell adjacent to the first solar subcell and having a second band gap smaller than the first band gap and having a base layer and an adjacent emitter layer, wherein the other layer adjacent to the emitter layer has an index of refraction substantially equal to that of the emitter layer; a graded interlayer adjacent to the second solar having a third band gap greater than said second band gap; and a lower solar subcell adjacent to the interlayer, and having a fourth band gap smaller than the second band gap, the third subcell being lattice mismatched with respect to the second subcell.

Abstract: A method of making a multijunction solar cell, including first and second solar cells on a substrate with a bypass diode having an intrinsic layer and operative for passing current when the multijunction solar cell is shaded. In one embodiment, a vertical sequence of solar cells are epitaxially grown on a first portion of the substrate, and the layers of the diode are epitaxially grown on a second portion of the substrate with the layers of the bypass diode being deposited subsequent to the layers of the top solar cell.

Abstract: A method and a multijunction solar device having a high band gap heterojunction middle solar cell are disclosed. In one embodiment, a triple-junction solar device includes bottom, middle, and top cells. The bottom cell has a germanium (Ge) substrate and a buffer layer, wherein the buffer layer is disposed over the Ge substrate. The middle cell contains a heterojunction structure, which further includes an emitter layer and a base layer that are disposed over the bottom cell. The top cell contains an emitter layer and a base layer disposed over the middle cell.