Abstract: A nitride semiconductor laser device of one embodiment of the present disclosure includes a single-crystal substrate, a base layer, a sheet-shaped structure, a light emitting layer, and a resonator mirror. The single-crystal substrate extends in one direction. The base layer is provided on the single-crystal substrate and includes a nitride semiconductor. The sheet-shaped structure is provided on the base layer to stand in a direction perpendicular to the base layer. The sheet-shaped structure has an area of a side surface that is greater than an area of an upper surface. The side surface extends in a longitudinal direction of the single-crystal substrate. The sheet-shaped structure includes a nitride semiconductor. The light emitting layer is provided at least on the side surface of the sheet-shaped structure. The light emitting layer includes a nitride semiconductor. The resonator mirror is provided by a pair of end surfaces of the sheet-shaped structure that oppose each other in the longitudinal direction.

Abstract: A semiconductor optical device has a multilayer structure 30 including a first compound semiconductor layer 31, an active layer 33, and a second compound semiconductor layer 32. A second electrode 42 is formed on the second compound semiconductor layer 32 through a contact layer 34. The contact layer 34 has a thickness of four or less atomic layers. When an interface between the contact layer 34 and the second compound semiconductor layer 32 is an xy-plane, a lattice constant along an x-axis of crystals constituting an interface layer 32A which is a part of the second compound semiconductor layer in contact with the contact layer 34 is x2, a lattice constant along a z-axis is z2, a length along an x-axis in one unit of crystals constituting the contact layer 34 is xc?, and a length along the z-axis is zc?, (zc?/xc?)>(z2/x2) is satisfied.

Abstract: A semiconductor optical device has a multilayer structure 30 including a first compound semiconductor layer 31, an active layer 33, and a second compound semiconductor layer 32. A second electrode 42 is formed on the second compound semiconductor layer 32 through a contact layer 34. The contact layer 34 has a thickness of four or less atomic layers. When an interface between the contact layer 34 and the second compound semiconductor layer 32 is an xy-plane, a lattice constant along an x-axis of crystals constituting an interface layer 32A which is a part of the second compound semiconductor layer in contact with the contact layer 34 is x2, a lattice constant along a z-axis is z2, a length along an x-axis in one unit of crystals constituting the contact layer 34 is xc?, and a length along the z-axis is zc?, (zc?/xc?)>(z2/x2) is satisfied.

Abstract: A semiconductor optical device has a multilayer structure 30 including a first compound semiconductor layer 31, an active layer 33, and a second compound semiconductor layer 32. A second electrode 42 is formed on the second compound semiconductor layer 32 through a contact layer 34. The contact layer 34 has a thickness of four or less atomic layers. When an interface between the contact layer 34 and the second compound semiconductor layer 32 is an xy-plane, a lattice constant along an x-axis of crystals constituting an interface layer 32A which is a part of the second compound semiconductor layer in contact with the contact layer 34 is x2, a lattice constant along a z-axis is z2, a length along an x-axis in one unit of crystals constituting the contact layer 34 is xc?, and a length along the z-axis is zc?, (zc?/xc?)>(z2/x2) is satisfied.

Abstract: A semiconductor optical device has a multilayer structure 30 including a first compound semiconductor layer 31, an active layer 33, and a second compound semiconductor layer 32. A second electrode 42 is formed on the second compound semiconductor layer 32 through a contact layer 34. The contact layer 34 has a thickness of four or less atomic layers. When an interface between the contact layer 34 and the second compound semiconductor layer 32 is an xy-plane, a lattice constant along an x-axis of crystals constituting an interface layer 32A which is a part of the second compound semiconductor layer in contact with the contact layer 34 is x2, a lattice constant along a z-axis is z2, a length along an x-axis in one unit of crystals constituting the contact layer 34 is xc?, and a length along the z-axis is zc?, (zc?/xc?)>(z2/x2) is satisfied.

Abstract: A semiconductor optical device has a multilayer structure 30 including a first compound semiconductor layer 31, an active layer 33, and a second compound semiconductor layer 32. A second electrode 42 is formed on the second compound semiconductor layer 32 through a contact layer 34. The contact layer 34 has a thickness of four or less atomic layers. When an interface between the contact layer 34 and the second compound semiconductor layer 32 is an xy-plane, a lattice constant along an x-axis of crystals constituting an interface layer 32A which is a part of the second compound semiconductor layer in contact with the contact layer 34 is x2, a lattice constant along a z-axis is z2, a length along an x-axis in one unit of crystals constituting the contact layer 34 is xc?, and a length along the z-axis is zc?, (zc?/xc?)>(z2/x2) is satisfied.

Abstract: A multi-junction solar cell that is lattice-matched with a base, and that includes a sub-cell having a desirable band gap is provided. A plurality of sub-cells are laminated, each including first and second compound semiconductor layers. At least one predetermined sub-cell is configured of first layers and a second layer. In each of the first layers, a 1-A layer and a 1-B layer are laminated. In the second layer, a 2-A layer and a 2-B layer are laminated. A composition A of the 1-A layer and the 2-A layer is determined based on a value of a band gap of the predetermined sub-cell. A composition B of the 1-B layer and the 2-B layer is determined based on a difference between a base lattice constant of the base and a lattice constant of the composition A. Thicknesses of 1-B layer and 2-B layer are determined based on difference between base lattice constant and a lattice constant of composition B, and on thickness of the 1-A layer and thickness of 2-A layer.

Abstract: A semiconductor optical device has a multilayer structure 30 including a first compound semiconductor layer 31, an active layer 33, and a second compound semiconductor layer 32. A second electrode 42 is formed on the second compound semiconductor layer 32 through a contact layer 34. The contact layer 34 has a thickness of four or less atomic layers. When an interface between the contact layer 34 and the second compound semiconductor layer 32 is an xy-plane, a lattice constant along an x-axis of crystals constituting an interface layer 32A which is a part of the second compound semiconductor layer in contact with the contact layer 34 is x2, a lattice constant along a z-axis is z2, a length along an x-axis in one unit of crystals constituting the contact layer 34 is xc?, and a length along the z-axis is zc?, (zc?/xc?)>(z2/x2) is satisfied.

Abstract: There is provided a multi-junction solar cell that reduces contact resistance of a junction portion and is capable of performing energy conversion with high efficiency. The multi-junction solar cell includes a plurality of sub-cells 11, 12, 13, and 14 that are laminated, the plurality of sub-cells 11, 12, 13, and 14 being configured of a plurality of compound semiconductor layers 11A, 11B, 11C, 12A, 12B, 12C, 13A, 13B, 13C, 14A, 14B, and 14C that are laminated. Amorphous connection layers 20A and 20B made of electrically-conductive material are provided in at least one place between the sub-cells 12 and 13 adjacent to each other.

Abstract: A multi-junction solar cell that is lattice-matched with a base, and that includes a sub-cell having a desirable band gap is provided. A plurality of sub-cells are laminated, each including first and second compound semiconductor layers. At least one predetermined sub-cell is configured of first layers and a second layer. In each of the first layers, a 1-A layer and a 1-B layer are laminated. In the second layer, a 2-A layer and a 2-B layer are laminated. A composition A of the 1-A layer and the 2-A layer is determined based on a value of a band gap of the predetermined sub-cell. A composition B of the 1-B layer and the 2-B layer is determined based on a difference between a base lattice constant of the base and a lattice constant of the composition A. Thicknesses of 1-B layer and 2-B layer are determined based on difference between base lattice constant and a lattice constant of composition B, and on thickness of the 1-A layer and thickness of 2-A layer.

Abstract: The present invention relates to a semiconductor laser device capable of reliably suppressing degradation of an end face due to interface oxidation and distortion application, and to a manufacturing method of the same. The semiconductor laser device has a laser structure portion 107 having opposite resonator faces 108 and 109, and protecting films 110 and 120 formed on at least one of the opposite resonator end faces, wherein the protecting films 110 and 120 are formed of nitride dielectric films having a multistage structure including amorphous layers 111 and 121 and polycrystal layers 112 and 122 in crystal structure, respectively, from aside in contact with the resonator faces.

Abstract: A light-emitting diode with (a) a substrate having at least one recessed portion on one main surface; (b) a sixth nitride-based III-V group compound semiconductor layer grown on the substrate without forming a space in the recessed portion; and (c) a third nitride-based III-V group compound semiconductor layer of a first conduction type, an active layer and a fourth nitride-based III-V group compound semiconductor layer of a second conduction type formed over the sixth nitride-based III-V group compound semiconductor layer, wherein, a dislocation occurring, in the sixth nitride-based III-V group compound semiconductor layer, from an interface with a bottom surface of the recessed portion in a direction vertical to the one main surface arrives at an inclined face or its vicinity of a triangle having the bottom surface of the recessed portion as a base and bends in a direction parallel to the one main surface.

Abstract: A method for making a light-emitting diode, which including the steps of: providing a substrate having at least one recessed portion on one main surface and growing a first nitride-based III-V group compound semiconductor layer through a state of making a triangle in section having a bottom surface of the recessed portion as a base thereby burying the recessed portion; laterally growing a second nitride-based III-V group compound semiconductor layer from the first nitride-based III-V group compound semiconductor layer over the substrate; and successively growing a third nitride-based III-V group compound semiconductor layer of a first conduction type, an active layer and a fourth nitride-based III-V group compound semiconductor layer of a second conduction type on the second nitride-based III-V group compound semiconductor layer.

Abstract: A method for making a light-emitting diode, which including the steps of: providing a substrate having at least one recessed portion on one main surface and growing a first nitride-based III-V group compound semiconductor layer through a state of making a triangle in section having a bottom surface of the recessed portion as a base thereby burying the recessed portion; laterally growing a second nitride-based III-V group compound semiconductor layer from the first nitride-based III-V group compound semiconductor layer over the substrate; and successively growing a third nitride-based III-V group compound semiconductor layer of a first conduction type, an active layer and a fourth nitride-based III-V group compound semiconductor layer of a second conduction type on the second nitride-based III-V group compound semiconductor layer.