Abstract: A semiconductor laser includes: a first semiconductor layer part including a semiconductor layer of a first conductivity type; an active layer disposed on the first semiconductor layer part; a second semiconductor layer part disposed on the active layer and including a semiconductor layer of a second conductivity type; a third semiconductor layer p100415-0433art disposed on the second semiconductor layer part and including a semiconductor layer containing a first concentration of an impurity of the first conductivity type; and a fourth semiconductor layer part disposed on the third semiconductor layer part and including a semiconductor layer containing a second concentration of the impurity of the first conductivity type, the second concentration being lower than the first concentration. The third semiconductor layer part is directly bonded to the fourth semiconductor layer part. At least one of the third semiconductor layer part or the fourth semiconductor layer part includes a photonic crystal.

Abstract: A light-emitting element includes: a first conductive semiconductor layer; a plurality of rods disposed on the first conductive semiconductor layer, the rods comprising a first conductive semiconductor; a first insulating film disposed on a surface of the first conductive semiconductor layer while being absent under the rods; a plurality of light-emitting layers disposed on lateral surfaces of the rods; a plurality of second conductive semiconductor layers disposed on outer sides of the light-emitting layers; and a plurality of second insulating films disposed at upper ends of the rods.

Abstract: A light emitting element includes: a substrate; a base layer disposed on the substrate; at least one rod-shaped light emitting portion comprising: a first conductivity type semiconductor rod disposed on the base layer and having a plurality of side surfaces arranged to form a polygonal column shape, an active layer formed of a semiconductor and covering the side surfaces of the first conductivity type semiconductor rod, and a second conductive type semiconductor layer covering the active layer. The active layer includes a plurality of well layers respectively disposed over at least two adjacent side surfaces among the plurality of side surfaces of the first conductivity type semiconductor rod. Adjacent well layers among the plurality of well layers are separated from each other along a ridge line where the at least two adjacent side surfaces are in contact with each other.

Abstract: A light-emitting element includes: a first conductive semiconductor layer; a plurality of rods disposed on the first conductive semiconductor layer, the rods comprising a first conductive semiconductor; a first insulating film disposed on a surface of the first conductive semiconductor layer while being absent under the rods; a plurality of light-emitting layers disposed on lateral surfaces of the rods; a plurality of second conductive semiconductor layers disposed on outer sides of the light-emitting layers; and a plurality of second insulating films disposed at upper ends of the rods.

Abstract: A method of manufacturing a light-emitting element includes: forming a plurality of masks on a surface of a first conductive semiconductor layer; forming a plurality of rods comprising a first conductive semiconductor by partially removing, in a depth direction, a portion of the first conductive semiconductor layer exposed from the masks by etching; forming an insulating film on the rods and a surface of a the remaining first conductive semiconductor layer; performing wet etching, in a state in which a mask covering the insulating film is not formed, to remove a first portion of the insulating film on lateral surfaces of the rods but retaining a second portion of the insulating film on a surface of the first conductive semiconductor layer; forming a plurality of light-emitting layers covering the lateral surfaces of the rods; and forming a plurality of second conductive semiconductor layers covering outer peripheries of the light-emitting layers.

Abstract: A light emitting element includes: a substrate; a base layer disposed on the substrate; at least one rod-shaped light emitting portion comprising: a first conductivity type semiconductor rod disposed on the base layer and having a plurality of side surfaces arranged to form a polygonal column shape, an active layer formed of a semiconductor and covering the side surfaces of the first conductivity type semiconductor rod, and a second conductive type semiconductor layer covering the active layer. The active layer includes a plurality of well layers respectively disposed over at least two adjacent side surfaces among the plurality of side surfaces of the first conductivity type semiconductor rod. Adjacent well layers among the plurality of well layers are separated from each other along a ridge line where the at least two adjacent side surfaces are in contact with each other.

Abstract: A light emitting element includes: a first conductivity type semiconductor rod having a plurality of side surfaces arranged to form a polygonal column shape; an active layer formed of a semiconductor and covering the side surfaces; and a second conductive type semiconductor layer covering the active layer. The active layer includes a plurality of well layers respectively disposed over at least two adjacent side surfaces among the plurality of side surfaces. Adjacent well layers among the plurality of well layers are separated from each other along a ridge line where the at least two adjacent side surfaces are in contact with each other. The active layer further includes a ridge portion formed of a semiconductor and disposed on the ridge line, the ridge portion connecting the adjacent well layers. A bandgap of the ridge portion is wider than a bandgap of each of the plurality of well layers.

Abstract: A method of manufacturing a light-emitting element includes: forming a plurality of masks on a surface of a first conductive semiconductor layer; forming a plurality of rods comprising a first conductive semiconductor by partially removing, in a depth direction, a portion of the first conductive semiconductor layer exposed from the masks by etching; forming an insulating film on the rods and a surface of a the remaining first conductive semiconductor layer; performing wet etching, in a state in which a mask covering the insulating film is not formed, to remove a first portion of the insulating film on lateral surfaces of the rods but retaining a second portion of the insulating film on a surface of the first conductive semiconductor layer; forming a plurality of light-emitting layers covering the lateral surfaces of the rods; and forming a plurality of second conductive semiconductor layers covering outer peripheries of the light-emitting layers.

Abstract: A method of manufacturing a light-emitting element includes: forming a plurality of rod-shaped layered structures by performing steps including: forming a first conductive-type semiconductor layer on a substrate, forming, on the first conductive-type semiconductor layer, an insulating film defining a plurality of openings and a plurality of rods of a first conductive-type semiconductor, wherein each of the rods is disposed through a respective one of the plurality of openings, forming a light-emitting layer covering outer surfaces of the plurality of rods, and forming a second conductive-type semiconductor layer covering outer surfaces of the light-emitting layer; forming a photoresist pattern covering a portion of the plurality of the rod-shaped layered structures; removing a portion of the insulating film in a region that is not covered by the photoresist pattern; and removing a portion of the plurality of rod-shaped layered structures in the region that is not covered by the photoresist pattern.

Abstract: A method of manufacturing a light-emitting element includes: forming a plurality of rod-shaped layered structures by performing steps including: forming a first conductive-type semiconductor layer on a substrate, forming, on the first conductive-type semiconductor layer, an insulating film defining a plurality of openings and a plurality of rods of a first conductive-type semiconductor, wherein each of the rods is disposed through a respective one of the plurality of openings, forming a light-emitting layer covering outer surfaces of the plurality of rods, and forming a second conductive-type semiconductor layer covering outer surfaces of the light-emitting layer; forming a photoresist pattern covering a portion of the plurality of the rod-shaped layered structures; removing a portion of the insulating film in a region that is not covered by the photoresist pattern; and removing a portion of the plurality of rod-shaped layered structures in the region that is not covered by the photoresist pattern.

Abstract: A light emitting element includes: a first conductivity type semiconductor rod having a plurality of side surfaces arranged to form a polygonal column shape; an active layer formed of a semiconductor and covering the side surfaces; and a second conductive type semiconductor layer covering the active layer. The active layer includes a plurality of well layers respectively disposed over at least two adjacent side surfaces among the plurality of side surfaces. Adjacent well layers among the plurality of well layers are separated from each other along a ridge line where the at least two adjacent side surfaces are in contact with each other. The active layer further includes a ridge portion formed of a semiconductor and disposed on the ridge line, the ridge portion connecting the adjacent well layers. A bandgap of the ridge portion is wider than a bandgap of each of the plurality of well layers.

Abstract: A method for producing a nitride semiconductor device. The method comprises providing a substrate made of a material other than a nitride semiconductor. The material has a hexagonal crystal structure. An upper face of the substrate has at least one flat section. The method further comprises growing a first nitride semiconductor layer on the upper face of the substrate. The first nitride semiconductor layer is made of monocrystalline AlN. The first nitride semiconductor layer has an upper face that is a +c plane. The first nitride semiconductor layer has a thickness in a range of 10 nm to 100 nm. The method further comprises growing a second nitride semiconductor layer on the upper face of the first nitride semiconductor layer. The second nitride semiconductor layer is made of InXAlYGa1?X?YN (0?X, 0?Y, X+Y<1).

Abstract: A method for producing a nitride semiconductor device. The method comprises providing a substrate made of a material other than a nitride semiconductor. The material has a hexagonal crystal structure. An upper face of the substrate has at least one flat section. The method further comprises growing a first nitride semiconductor layer on the upper face of the substrate. The first nitride semiconductor layer is made of monocrystalline AlN. The first nitride semiconductor layer has an upper face that is a +c plane. The first nitride semiconductor layer has a thickness in a range of 10 nm to 100 nm. The method further comprises growing a second nitride semiconductor layer on the upper face of the first nitride semiconductor layer. The second nitride semiconductor layer is made of InXAlYGa1?X?YN (0?X, 0?Y, X+Y<1).

Abstract: A method for producing a nitride semiconductor device. The method comprises providing a substrate made of a material other than a nitride semiconductor. The material has a hexagonal crystal structure. An upper face of the substrate has at least one flat section. The method further comprises growing a first nitride semiconductor layer on the upper face of the substrate. The first nitride semiconductor layer is made of monocrystalline AlN. The first nitride semiconductor layer has an upper face that is a +c plane. The first nitride semiconductor layer has a thickness in a range of 10 nm to 100 nm. The method further comprises growing a second nitride semiconductor layer on the upper face of the first nitride semiconductor layer. The second nitride semiconductor layer is made of InXAlYGa1-X-YN (0?X, 0?Y, X+Y<1).

Abstract: A method for producing a nitride semiconductor device. The method comprises providing a substrate made of a material other than a nitride semiconductor. The material has a hexagonal crystal structure. An upper face of the substrate has at least one flat section. The method further comprises growing a first nitride semiconductor layer on the upper face of the substrate. The first nitride semiconductor layer is made of monocrystalline AlN. The first nitride semiconductor layer has an upper face that is a +c plane. The first nitride semiconductor layer has a thickness in a range of 10 nm to 100 nm. The method further comprises growing a second nitride semiconductor layer on the upper face of the first nitride semiconductor layer. The second nitride semiconductor layer is made of InXAlYGa1-X-YN (0?X, 0?Y, X+Y<1).

Abstract: A method for producing a nitride semiconductor device. The method comprises providing a substrate made of a material other than a nitride semiconductor. The material has a hexagonal crystal structure. An upper face of the substrate has at least one flat section. The method further comprises growing a first nitride semiconductor layer on the upper face of the substrate. The first nitride semiconductor layer is made of monocrystalline AlN. The first nitride semiconductor layer has an upper face that is a +c plane. The first nitride semiconductor layer has a thickness in a range of 10 nm to 100 nm. The method further comprises growing a second nitride semiconductor layer on the upper face of the first nitride semiconductor layer. The second nitride semiconductor layer is made of InXAlYGa1-X-YN (0?X, 0?Y, X+Y<1).

Abstract: A nitride semiconductor light-emitting element includes an n-side layer; a p-side layer; and a light-emitting layer having a multiple quantum well structure, the light-emitting layer being located between the n-side layer and the p-side layer. The light-emitting layer includes: an n-side first barrier layer, a plurality of well layers, including an n-side first well layer, an n-side second well layer, and one or more additional well layers, and a plurality of intermediate layers, including an n-side first intermediate barrier layer and one or more additional intermediate barrier layers. A band gap of the n-side first intermediate barrier layer is smaller than a band gap of the n-side first barrier layer. A band gap of each of the one or more additional intermediate barrier layers is larger than a band gap of the n-side first intermediate barrier layer.

Abstract: A method of manufacturing a semiconductor device includes: forming a ridge on a semiconductor layer stacked on a substrate by removing a part of the semiconductor layer; forming an electrode on the ridge so as to have a flat portion having a flat surface substantially parallel to the upper surface of the ridge and sloped portions on both sides of the flat portion with each of the sloped portions having a sloped surface that is sloped with respect to the upper surface of the ridge; forming a protective film disposed on each side of the ridge to cover a region from the side surface of the ridge to the sloped surface of the sloped portion of the electrode; and forming a pad electrode at least on an upper surface of the electrode and the protective film.

Abstract: A method for producing a nitride semiconductor device. The method comprises providing a substrate made of a material other than a nitride semiconductor. The material has a hexagonal crystal structure. An upper face of the substrate has at least one flat section. The method further comprises growing a first nitride semiconductor layer on the upper face of the substrate. The first nitride semiconductor layer is made of monocrystalline AlN. The first nitride semiconductor layer has an upper face that is a +c plane. The first nitride semiconductor layer has a thickness in a range of 10 nm to 100 nm. The method further comprises growing a second nitride semiconductor layer on the upper face of the first nitride semiconductor layer. The second nitride semiconductor layer is made of InXAlYGa1-X-YN (0?X, 0?Y, X+Y<1).

Abstract: A method for producing a nitride semiconductor device. The method comprises providing a substrate made of a material other than a nitride semiconductor. The material has a hexagonal crystal structure. An upper face of the substrate has at least one flat section. The method further comprises growing a first nitride semiconductor layer on the upper face of the substrate. The first nitride semiconductor layer is made of monocrystalline AlN. The first nitride semiconductor layer has an upper face that is a +c plane. The first nitride semiconductor layer has a thickness in a range of 10 nm to 100 nm. The method further comprises growing a second nitride semiconductor layer on the upper face of the first nitride semiconductor layer. The second nitride semiconductor layer is made of InXAlYGa1-X-YN (0?X, 0?Y, X+Y<1).