摘要:
A semiconductor emitter, or a precursor therefor, has a substrate and one or more textured semiconductor layers deposited onto the substrate in a nonpolar orientation. The textured layers enhance light extraction, and the use of nonpolar orientation greatly enhances internal quantum efficiency compared to conventional devices. Both the internal and external quantum efficiencies of emitters of the invention can be 70-80% or higher. The invention provides highly efficient light emitting diodes suitable for solid state lighting.
摘要:
A semiconductor emitter, or a precursor therefor, has a substrate and one or more textured semiconductor layers deposited onto the substrate in a nonpolar orientation. The textured layers enhance light extraction, and the use of nonpolar orientation greatly enhances internal quantum efficiency compared to conventional devices. Both the internal and external quantum efficiencies of emitters of the invention can be 70-80% or higher. The invention provides highly efficient light emitting diodes suitable for solid state lighting.
摘要:
A multijunction (MJ) solar cell grown on an InP substrate using materials that are lattice-matched to InP. In an exemplary three-junction embodiment, the top cell is formed from In1-xAlxAs1-ySby (with x and y adjusted so as to achieve lattice-matching with InP, hereafter referred to as InAlAsSb), the middle cell from In1-a-bGaaAlbAs (with a and b adjusted so as to achieve lattice-matching with InP, hereafter referred to as InGaAlAs), and the bottom cell also from InGaAlAs, but with a much lower Al composition, which in some embodiments can be zero so that the material is InGaAs. Tunnel junctions (TJs) connect the junctions and allow photo-generated current to flow. In an exemplary embodiment, an InAlAsSb TJ connects the first and second junctions, while an InGaAlAs TJ connects the second and third junctions.
摘要:
A multijunction (MJ) solar cell grown on an InP substrate using materials that are lattice-matched to InP. In an exemplary three-junction embodiment, the top cell is formed from In1-xAlxAs1-ySby (with x and y adjusted so as to achieve lattice-matching with InP, hereafter referred to as InAlAsSb), the middle cell from In1-a-bGaaAlbAs (with a and b adjusted so as to achieve lattice-matching with InP, hereafter referred to as InGaAlAs), and the bottom cell also from InGaAlAs, but with a much lower Al composition, which in some embodiments can be zero so that the material is InGaAs. Tunnel junctions (TJs) connect the junctions and allow photo-generated current to flow. In an exemplary embodiment, an InAlAsSb TJ connects the first and second junctions, while an InGaAlAs TJ connects the second and third junctions.
摘要:
A laser apparatus configured for epitaxial-side-down mounting on a heat sink. The laser apparatus includes a semiconductor laser structure and at least one post on a substrate where the laser structure and post are separated from each other by a channel. The laser structure and the posts optionally are coated with a heat-spreading material layer and are configured so that the maximum height of the posts is about the same as the maximum height of the laser structure. When the laser apparatus is mounted to a heat sink in an epi-down configuration using solder applied to the top of the laser structure and the at least one post, the channels between the at least one post and the laser structure provide a relief flow path for the solder and ensure that the laser structure does not come directly into contact with the solder.
摘要:
A laser apparatus configured for epitaxial-side-down mounting on a heat sink. The laser apparatus includes a semiconductor laser structure and at least one post on a substrate where the laser structure and post are separated from each other by a channel. The laser structure and the posts optionally are coated with a heat-spreading material layer and are configured so that the maximum height of the posts is about the same as the maximum height of the laser structure. When the laser apparatus is mounted to a heat sink in an epi-down configuration using solder applied to the top of the laser structure and the at least one post, the channels between the at least one post and the laser structure provide a relief flow path for the solder and ensure that the laser structure does not come directly into contact with the solder.