Abstract: The present disclosure generally relates to a solar cell device that a first Bragg reflector disposed below a first solar cell and a second Bragg reflector disposed below the first Bragg reflector, wherein the first solar cell comprises a dilute nitride composition and 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 the second Bragg reflector is operable to reflect a third range of wavelengths back into the first solar cell, and the first Bragg reflector and the second Bragg reflector are 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.

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 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: 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: 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: The present disclosure generally relates to a solar cell device that a first Bragg reflector disposed below a first solar cell and a second Bragg reflector disposed below the first Bragg reflector, wherein the first solar cell comprises a dilute nitride composition and 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 the second Bragg reflector is operable to reflect a third range of wavelengths back into the first solar cell, and the first Bragg reflector and the second Bragg reflector are 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.

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: In one aspect, semiconductor structures are described herein. A semiconductor structure, in some implementations, comprises a first semiconductor layer having a first bandgap and a first lattice constant and a second semiconductor layer having a second bandgap and a second lattice constant. The second lattice constant is lower than the first lattice constant. Additionally, a transparent metamorphic buffer layer is disposed between the first semiconductor layer and the second semiconductor layer. The buffer layer has a constant or substantially constant bandgap and a varying lattice constant. The varying lattice constant is matched to the first lattice constant adjacent the first semiconductor layer and matched to the second lattice constant adjacent the second semiconductor layer. The buffer layer comprises a first portion comprising AlyGazIn(1-y-z)As and a second portion comprising GaxIn(1-x)P.

Abstract: A tunnel junction for a semiconductor device is disclosed. The tunnel junction includes a n-doped tunnel layer and a p-doped tunnel layer. The p-doped tunnel layer is constructed of aluminum gallium arsenide antimonide (AlGaAsSb). A semiconductor device including the tunnel junction with the p-doped tunnel layer constructed of AlGaAsSb is also disclosed.

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: 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: In one aspect, semiconductor structures are described herein. A semiconductor structure, in some implementations, comprises a first semiconductor layer having a first bandgap and a first lattice constant and a second semiconductor layer having a second bandgap and a second lattice constant. The second lattice constant is lower than the first lattice constant. Additionally, a transparent metamorphic buffer layer is disposed between the first semiconductor layer and the second semiconductor layer. The buffer layer has a constant or substantially constant bandgap and a varying lattice constant. The varying lattice constant is matched to the first lattice constant adjacent the first semiconductor layer and matched to the second lattice constant adjacent the second semiconductor layer. The buffer layer comprises a first portion comprising AlyGazIn(1-y-z)As and a second portion comprising GaxIn(1-x)P.

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: A semiconductor device may include a first subassembly and a second subassembly. The first subassembly may include a first bonding layer. The second subassembly may include a second substrate and a second bonding layer directly bonded to the first bonding layer. The first bonding layer and the second bonding layer may be lattice-mismatched to one another. At least one of the following may be selected: the first bonding layer is lattice-mismatched to the first substrate, and the second bonding layer is lattice-mismatched to the second substrate.

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: 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: A semiconductor device may include a first subassembly and a second subassembly. The first subassembly may include a first bonding layer. The second subassembly may include a second substrate and a second bonding layer directly bonded to the first bonding layer. The first bonding layer and the second bonding layer may be lattice-mismatched to one another. At least one of the following may be selected: the first bonding layer is lattice-mismatched to the first substrate, and the second bonding layer is lattice-mismatched to the second substrate.

Abstract: An apparatus and method for making a solar cell assembly. An apparatus in accordance with the present invention comprises a substrate, at least a first solar cell, coupled to a first side of the substrate, the first side of the substrate to be exposed to light such that the at least first solar cell generates a current when exposed to the light, and a bypass diode, formed on a second side of the substrate, the second side of the substrate being substantially opposite the first side of the substrate, such that the bypass diode is monolithically integrated with the at least first solar cell.