Abstract: The technology relates to producing an optoelectronic device. A method for forming an optoelectronic device on a substrate may include growing an epitaxial structure on the substrate, wherein the substrate comprises a semiconductor material having a lattice constant between 5.7 and 6.0 Angstroms, and wherein the epitaxial structure includes an epitaxial device layer, then depositing a metal layer on the epitaxial structure, and selectively removing the epitaxial layer, thereby separating the optoelectronic device from the substrate. An optoelectronic device may include an optoelectronic device structure including an epitaxial device layer having a lattice constant between 5.7 and 6.0 Angstroms, a metal layer deposited onto a surface of the optoelectronic device structure, and a carrier structure, wherein the optoelectronic device comprises a thin film, single crystal device.

Abstract: Tunnel junctions for multijunction solar cells are provided. According to an aspect of the invention, a tunnel junction includes a first layer including p-type AlGaAs, a second layer including n-type GaAs, wherein the second layer is a quantum well, and a third layer including n-type AlGaAs or n-type lattice matched AlGaInP. The quantum well can be GaAs or AlxGaAs with x being more than about 40%, and lattice matched GaInAsNSb in the Eg range of from about 0.8 to about 1.4 eV.

Abstract: Aspects of the disclosure relate to processes for epitaxial growth of III-V compound of (Al)GaInP material at high rates, such as about 8 ?m/hr, 10 ?m/hr, 20 ?m/hr, 30 ?m/hr, 40 ?m/hr, and 8-120 ?m/hr deposition rates. The high growth-rate deposited (Al)InGaP materials or films may be utilized in solar, semiconductor, or other electronic device applications. The Group III/V materials may be formed or grown on a sacrificial layer disposed on or over the support substrate during a chemical vapor deposition process. Subsequently, the Group III/V materials may be removed from the support substrate during an epitaxial lift off (ELO) process. The Group III/V materials are thin films of epitaxially grown layers containing gallium aluminum indium phosphide, gallium indium phosphide, derivatives thereof, alloys thereof, or combinations thereof.

Abstract: Tunnel junctions for multijunction solar cells are provided. According to an aspect of the invention, a tunnel junction includes a first layer including p-type AlGaAs, a second layer including n-type GaAs, wherein the second layer is a quantum well, and a third layer including n-type AlGaAs or n-type lattice matched AlGaInP. The quantum well can be GaAs or AlxGaAs with x being more than about 40%, and lattice matched GaInAsNSb in the Eg range of from about 0.8 to about 1.4 eV.