Abstract: A method of forming a multijunction solar cell comprising an upper subcell, a middle subcell, and a lower subcell comprising providing first substrate for the epitaxial growth of semiconductor material; forming a first solar subcell on said substrate having a first band gap; forming a second solar subcell over said first subcell having a second band gap smaller than said first band gap; and forming a grading interlayer over said second sub cell having a third band gap larger than said second band gap forming a third solar subcell having a fourth band gap smaller than said second band gap such that said third subcell is lattice mis-matched with respect to said second subcell.

Abstract: A method of forming a plurality of discrete, interconnected solar cells mounted on a carrier by providing a first semiconductor substrate; depositing on the first substrate a sequence of layers of semiconductor material forming a solar cell structure; forming a metal back contact layer over the solar cell structure; mounting a carrier on top of the metal back contact; removing the first substrate; and lithographically patterning and etching the solar cell structure to form a plurality of discrete solar cells mounted on the carrier.

Abstract: A method of forming a multijunction solar cell comprising an upper subcell, a middle subcell, and a lower subcell comprising providing first substrate for the epitaxial growth of semiconductor material; forming a first solar subcell on said substrate having a first band gap; forming a second solar subcell over said first subcell having a second band gap smaller than said first band gap; and forming a grading interlayer over said second subcell having a third band gap larger than said second band gap forming a third solar subcell having a fourth band gap smaller than said second band gap such that said third subcell is lattice mismatched with respect to said second subcell.

Abstract: A multijunction solar cell including a window layer with a gradation in doping from the region in the window layer adjacent to the emitter region to the region in the window layer adjacent to the surface layer overlying the window layer, so that minority carriers in the window layer experience an electric field which would tend to drive them in the direction of the emitter layer, thereby increasing the efficiency of the solar cell.

Abstract: A system for generating electrical power from solar radiation utilizing a thin film III-V compound multijunction semiconductor solar cell mounted on a support in a non-planar configuration.

Abstract: A multijunction solar cell including a window layer with a gradation in doping; an upper first solar subcell having a first band gap adjacent to the window layer; a second solar subcell adjacent to said first solar subcell; a first graded interlayer adjacent to said second solar subcell, said first graded interlayer having a third band gap greater than said second band gap; a third solar subcell adjacent to said first graded interlayer; a second interlayer adjacent to said third solar subcell, said second graded interlayer having a fifth band gap greater than said fourth band gap; a fourth solar subcell adjacent to said second graded interlayer, such that said fourth subcell is lattice mismatched with respect to said third subcell.

Abstract: A method of forming a plurality of discrete, interconnected solar cells mounted on a carrier by providing a first semiconductor substrate; depositing on the first substrate a sequence of layers of semiconductor material forming a solar cell structure; forming a metal back contact layer over the solar cell structure; mounting a carrier on top of the metal back contact; removing the first substrate; and lithographically patterning and etching the solar cell structure to form a plurality of discrete solar cells mounted on the carrier.

Abstract: A photovoltaic solar cell for producing energy from the sun including a germanium substrate including a first photoactive junction and forming a bottom solar subcell; a gallium arsenide middle cell disposed on said substrate; an indium gallium phosphide top cell disposed over the middle cell; and a surface grid including a plurality of spaced apart grid lines, wherein the grid lines have a thickness greater than 7 microns, and each grid line has a cross-section in the shape of a trapezoid with a cross-sectional area between 45 and 55 square microns.

Abstract: The present disclosure provides a process for manufacturing a solar cell by selectively freeing an epitaxial layer from a single crystal substrate upon which it was grown. In some embodiments the process includes, among other things, providing a first substrate; depositing a separation layer on said first substrate; depositing on said separation layer a sequence of layers of semiconductor material forming a solar cell; mounting and bonding a flexible support on top of the sequence of layers; etching said separation layer while applying an agitating action to the etchant solution so as to remove said flexible support with said epitaxial layer from said first substrate.

Abstract: A system for the generation of electrical power from sunlight includes a solar cell assembly with at least two sets of solar cells, each of these sets being adapted to a set-specific light frequency spectrum so as to convert light having said set-specific frequency spectrum into electrical energy with an optimized energy conversion efficiency. The system is arranged to respond to changes in the frequency spectrum of the sunlight, for example, in accordance with the time of the day, by causing the sunlight to selectively impinge on one or another of the different sets of solar cells. Thus, an enhanced energy conversion efficiency of the system is obtained.

Abstract: Inverted metamorphic multijunction solar cells having a heterojunction middle subcell and a graded interlayer, and methods of making same, are disclosed herein. The present disclosure provides a method of manufacturing a solar cell using an MOCVD process, wherein the graded interlayer is composed of (InxGa1-x)y Al1-yAs, and is formed in the MOCVD reactor so that it is compositionally graded to lattice match the middle second subcell on one side and the lower third subcell on the other side, with the values for x and y computed and the composition of the graded interlayer determined so that as the layer is grown in the MOCVD reactor, the band gap of the graded interlayer remains constant at 1.5 eV throughout the thickness of the graded interlayer.

Abstract: A method of forming a plurality of discrete, interconnected solar cells mounted on a carrier by providing a first semiconductor substrate; depositing on the first substrate a sequence of layers of semiconductor material forming a solar cell structure; forming a metal back contact layer over the solar cell structure; mounting a carrier on top of the metal back contact; removing the first substrate; and lithographically patterning and etching the solar cell structure to form a plurality of discrete solar cells mounted on the carrier.

Abstract: Apparatus and Method for Optimizing the Efficiency of a Bypass Diode in Solar Cells. In a preferred embodiment, a layer of TiAu is placed in an etch in a solar cell with a contact at a doped layer of GaAs. Electric current is conducted through a diode and away from the main cell by passing through the contact point at the GaAs and traversing a lateral conduction layer. These means of activating, or “turning on” the diode, and passing the current through the circuit results in greater efficiencies than in prior art devices. The diode is created during the manufacture of the other layers of the cell and does not require additional manufacturing.

Abstract: A method of manufacturing a solar cell by providing a first substrate; depositing sequentially on the first substrate a plurality of semiconductor layers, the plurality of semiconductor layers comprising a first layer and a last layer in the direction of deposition; forming a backside contact layer on the last semiconductor layer; forming on the last semiconductor layer a back cathode contact isolated from at least a first portion of the backside contact layer, the first portion forming the anode contact; attaching a second substrate on the backside contact layer and removing the first substrate to expose the first semiconductor layer and to define a front surface and an opposite back surface of a solar cell; forming a front cathode contact on the front surface of the solar cell; etching a first trench through the plurality of semiconductor layers to define an active portion of the solar cell with a first mesa structure including the front cathode contact and the anode contact and being surrounded by the firs

Abstract: A multijunction solar cell including an upper first solar subcell having a first band gap; a second solar subcell adjacent to the first solar subcell and having a second band gap smaller than the first band gap; a graded interlayer adjacent to the second solar subcell, the first graded interlayer having a third band gap greater than the second band gap; and a third solar subcell adjacent to the graded interlayer, the third subcell 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. A lower fourth solar subcell is provided adjacent to the third subcell and lattice matched thereto, the lower fourth subcell having a fifth band gap smaller than the fourth band gap.

Abstract: A multijunction solar cell including an upper first solar subcell, and the base-emitter junction of the upper first solar subcell being a homojunction; a second solar subcell adjacent to said first solar subcell; a third solar subcell adjacent to said second solar subcell. A first graded interlayer is provided adjacent to said third solar subcell. A fourth solar subcell is provided adjacent to said first graded interlayer, said fourth subcell is lattice mismatched with respect to said third subcell. A second graded interlayer is provided adjacent to said fourth solar subcell; and a lower fifth solar subcell is provided adjacent to said second graded interlayer, said lower fifth subcell is lattice mismatched with respect to said fourth subcell.

Abstract: A method of forming a multijunction solar cell string by mounting first and second multijunction solar cells on a first side of a perforated carrier; attaching a first electrical interconnect to the contact pad of said first multijunction solar cell, the electrical interconnect extending through said perforated carrier; attaching a second electrical interconnect to the metal contact layer of said second multijunction solar cell, the electrical interconnect extending through said perforated carrier; and connecting said first electrical interconnect to said second electrical interconnect.

Abstract: A method of manufacturing a solar cell by providing a first semiconductor substrate and depositing a first sequence of layers of semiconductor material to form a first solar subcell, including a first bond layer disposed on the top of the first sequence of layers. A second semiconductor substrate is provided, and on the top surface of the second substrate a second sequence of layers of semiconductor material is deposited forming at least a second solar subcell. A second bond layer is disposed on the top of said second sequence of layers. The first solar subcell is mounted on top of the second solar subcell by joining the first bond layer to the second bond layer in an ultra high vacuum chamber, and the first semiconductor substrate is removed.