Abstract: Device structures, apparatuses, and methods are disclosed for photovoltaic cells that may be a single-junction or multijunction solar cells, with at least a first layer comprising a group-IV semiconductor in which part of the cell comprises a second layer comprising a III-V semiconductor or group-IV semiconductor having a different composition than the group-IV semiconductor of the first layer, such that a heterostructure is formed between the first and second layers.

Abstract: A solar cell includes a first layer having a first-layer lattice parameter, a second layer having a second-layer lattice parameter different from the first-layer lattice parameter, wherein the second layer includes a photoactive second-layer material; and a third layer having a third-layer lattice parameter different from the second-layer lattice parameter, wherein the third layer includes a photoactive third-layer material. A transparent buffer layer extends between and contacts the second layer and the third layer and has a buffer-layer lattice parameter that varies with increasing distance from the second layer toward the third layer, so as to lattice match to the second layer and to the third layer. There may be additional subcell layers and buffer layers in the solar cell.

Abstract: A solar cell includes a first layer having a first-layer lattice parameter, a second layer having a second-layer lattice parameter different from the first-layer lattice parameter, wherein the second layer includes a photoactive second-layer material; and a third layer having a third-layer lattice parameter different from the second-layer lattice parameter, wherein the third layer includes a photoactive third-layer material. A transparent buffer layer extends between and contacts the second layer and the third layer and has a buffer-layer lattice parameter that varies with increasing distance from the second layer toward the third layer, so as to lattice match to the second layer and to the third layer. There may be additional subcell layers and buffer layers in the solar cell.

Abstract: The present disclosure generally relates to a solar cell device that includes a substrate comprising a front side surface and a backside surface; an epitaxial region overlying the substrate, wherein the epitaxial region comprises a first Bragg reflector disposed below a first solar cell, wherein the first solar cell has a first bandgap, wherein the first Bragg reflector is operable to reflect a first range of radiation wavelengths back into the first solar cell, and is operable to cool the solar cell device by reflecting a second range of radiation wavelengths that are outside the photogeneration wavelength range of the first solar cell or that are weakly absorbed by the first solar cell, and may additionally comprise a second Bragg reflector operable to reflect a third range of radiation wavelengths back into the first solar cell.

Abstract: In one aspect, optoelectronic devices are described herein. In some implementations, an optoelectronic device comprises a photovoltaic cell. The photovoltaic cell comprises a space-charge region, a quasi-neutral region, and a low bandgap absorber region (LBAR) layer or an improved transport (IT) layer at least partially positioned in the quasi-neutral region of the cell.

Abstract: In one aspect, optoelectronic devices are described herein. In some implementations, an optoelectronic device comprises a photovoltaic cell. The photovoltaic cell comprises a space-charge region, a quasi-neutral region, and a low bandgap absorber region (LBAR) layer or an improved transport (IT) layer at least partially positioned in the quasi-neutral region of the cell.

Abstract: Photovoltaic (PV) cell structures are disclosed. In one example embodiment, a PV cell includes an emitter layer, a base layer adjacent to the emitter layer, and a back surface field (BSF) layer adjacent to the base layer. The BSF layer includes a first layer, and a second layer adjacent to the first layer. The first layer includes a first material and the second layer includes a second material different than the first material.

Abstract: Methods and apparatuses for a dual heterojunction multijunction solar cell are disclosed. A method in accordance with the present invention comprises growing a base material for a solar cell, growing at least one dual heterojunction on the base material, and growing an emitter on the at least one dual heterojunction. An apparatus in accordance with the present invention comprises a substrate, and a first subcell, coupled to the substrate, wherein the first subcell comprises a base region, coupled to the substrate, an emitter region, and at least one dual heterojunction, coupled between the base region and the emitter region, wherein the at least one dual heterojunction has a lower bandgap than the emitter region.

Abstract: Photovoltaic (PV) cell structures are disclosed. In one example embodiment, a PV cell includes an emitter layer, a base layer adjacent to the emitter layer, and a back surface field (BSF) layer adjacent to the base layer. The BSF layer includes a first layer, and a second layer adjacent to the first layer. The first layer includes a first material and the second layer includes a second material different than the first material.

Abstract: Systems, methods, and apparatus for light collection and conversion to electricity are disclosed herein. The disclosed method involves receiving, by at least one concentrating element (e.g., a lens), light from at least one light source, where the light comprises direct light and diffuse light. The method further involves focusing, by at least one concentrating element, the direct light onto at least one concentrator photovoltaic cell. Also, the method involves passing, by at least one concentrating element, the diffuse light onto at least one solar cell of an array of solar cells arranged on a flat plate, where at least one concentrator photovoltaic cell is bonded on top of at least one of the solar cells in the array. In addition, the method involves collecting, by at least one concentrator photovoltaic cell, the direct light. Further, the method involves collecting, by at least one solar cell, the diffuse light.

Abstract: A semiconductor device structure having increased photogenerated current density, and increased current output is disclosed. The device includes low bandgap absorber regions that increase the range of wavelengths at which photogeneration of charge carriers takes place, and for which useful current can be collected. The low bandgap absorber regions may be strain balanced by strain-compensation regions, and the low bandgap absorber regions and strain-compensation regions may be formed from the same ternary semiconductor family. The device may be a solar cell, subcell, or other optoelectronic device with a metamorphic or lattice-mismatched base layer, for which the low bandgap absorber region improves the effective bandgap combination of subcells and current balance within the multijunction cell, for higher efficiency conversion of the solar spectrum.

Abstract: Methods and apparatuses for a dual heterojunction multijunction solar cell are disclosed. A method in accordance with the present invention comprises growing a base material for a solar cell, growing at least one dual heterojunction on the base material, and growing an emitter on the at least one dual heterojunction. An apparatus in accordance with the present invention comprises a substrate, and a first subcell, coupled to the substrate, wherein the first subcell comprises a base region, coupled to the substrate, an emitter region, and at least one dual heterojunction, coupled between the base region and the emitter region, wherein the at least one dual heterojunction has a lower bandgap than the emitter region.

Abstract: Device structures, apparatuses, and methods are disclosed for photovoltaic cells that may be a single-junction or multijunction solar cells, with at least a first layer comprising a group-IV semiconductor in which part of the cell comprises a second layer comprising a III-V semiconductor or group-IV semiconductor having a different composition than the group-IV semiconductor of the first layer, such that a heterostructure is formed between the first and second layers.

Abstract: Methods and apparatuses for a dual heterojunction multijunction solar cell are disclosed. A method in accordance with the present invention comprises growing a base material for a solar cell, growing at least one dual heterojunction on the base material, and growing an emitter on the at least one dual heterojunction. An apparatus in accordance with the present invention comprises a substrate, and a first subcell, coupled to the substrate, wherein the first subcell comprises a base region, coupled to the substrate, an emitter region, and at least one dual heterojunction, coupled between the base region and the emitter region, wherein the at least one dual heterojunction has a lower bandgap than the emitter region.

Abstract: A method of disordering a layer of an optoelectronic device including; growing a plurality of lower layers; introducing an isoelectronic surfactant; growing a layer; allowing the surfactant to desorb; and growing subsequent layers all performed at a low pressure of 25 torr.

Abstract: Device structures, apparatuses, and methods are disclosed for photovoltaic cells that may be a single-junction or multijunction solar cells, with at least a first layer comprising a group-IV semiconductor in which part of the cell comprises a second layer comprising a III-V semiconductor or group-IV semiconductor having a different composition than the group-IV semiconductor of the first layer, such that a heterostructure is formed between the first and second layers.

Abstract: Device structures, apparatuses, and methods are disclosed for photovoltaic cells that may be a single-junction or multijunction solar cells, with at least a first layer comprising a group-IV semiconductor in which part of the cell comprises a second layer comprising a III-V semiconductor or group-IV semiconductor having a different composition than the group-IV semiconductor of the first layer, such that a heterostructure is formed between the first and second layers.

Abstract: Device structures, apparatuses, and methods are disclosed for photovoltaic cells that may be a single-junction or multijunction solar cells, with at least a first layer comprising a group-IV semiconductor in which part of the cell comprises a second layer comprising a III-V semiconductor or group-IV semiconductor having a different composition than the group-IV semiconductor of the first layer, such that a heterostructure is formed between the first and second layers.

Abstract: Device structures, apparatuses, and methods are disclosed for photovoltaic cells that may be a single junction or multijunction solar cells, with at least a first layer comprising a group-IV semiconductor in which part of the cell comprises a second layer comprising a III-V semiconductor or group-IV semiconductor having a different composition than the group-IV semiconductor of the first layer, such that a heterostructure is formed between the first and second layers.

Abstract: Device structures, apparatuses, and methods are disclosed for photovoltaic cells that may be a single junction or multijunction solar cells, with at least a first layer comprising a group-IV semiconductor in which part of the cell comprises a second layer comprising a III-V semiconductor or group-IV semiconductor having a different composition than the group-IV semiconductor of the first layer, such that a heterostructure is formed between the first and second layers.