Abstract: The semiconductor light-emitting element includes an n-type semiconductor layer; an active layer on the n-type semiconductor layer; a p-type semiconductor layer on the active layer; a p-side contact electrode in contact with the p-type semiconductor layer; a p-side current diffusion layer on the p-side contact electrode; an n-side contact electrode in contact with the n-type semiconductor layer; and an n-side current diffusion layer that includes a first current diffusion layer on the n-side contact electrode, and a second current diffusion layer on the first current diffusion layer, and including a TiN layer. A height difference between upper surfaces of the p-side contact electrode and the first current diffusion layer is 100 nm or smaller; and a height difference between upper surfaces of the p-side current diffusion layer and the second current diffusion layer is 100 nm or smaller.

Abstract: A nitride semiconductor light-emitting element includes a light-emitting layer comprising a well layer comprising AlGaN and emitting ultraviolet light; an electron blocking layer being located on the light-emitting layer and comprising AlGaN with a first Al composition ratio higher than an Al composition ratio of the well layer; and a p-type cladding layer being located on the electron blocking layer, comprising AlGaN with a second Al composition ratio higher than the Al composition ratio of the well layer and lower than the first Al composition ratio, and being doped with a predetermined concentration of a p-type dopant. An interface between the electron blocking layer and the p-type cladding layer is doped with not less than a predetermined amount of an n-type dopant.

Abstract: A method of manufacturing a semiconductor light-emitting element includes: forming an active layer of an AlGaN-based semiconductor material on an n-type semiconductor layer of an n-type AlGaN-based semiconductor material; forming a p-type semiconductor layer on the active layer; removing a portion of the p-type semiconductor layer and the active layer by dry etching to expose an upper surface of the n-type semiconductor layer; treating the upper surface of the n-type semiconductor layer with a plasma in an atmosphere including an N2 gas and an NH3 gas; and forming a n-side contact electrode on the upper surface of the n-type semiconductor layer treated with the plasma.

Abstract: A semiconductor light-emitting element includes: a first protective layer made of SiO2 and a second protective layer made of SiNx. The first protective layer covers the n-type semiconductor layer, the active layer, the p-type semiconductor layer, the p-side contact electrode, the n-side contact electrode, the p-side current diffusion layer, and the n-side current diffusion layer in portions different from portions of the first p-side pad opening and the first n-side pad opening. The second protective layer covers the first protective layer in a portion different from portions of the second p-side pad opening and the second n-side pad opening, covers an inner circumferential surface of the first protective layer that defines the first p-side pad opening, and covers an inner circumferential surface of the first protective layer that defines the first n-side pad opening.

Abstract: A nitride semiconductor light-emitting element includes a light-emitting layer comprising a well layer comprising AlGaN and emitting ultraviolet light; an electron blocking layer being located on the light-emitting layer and comprising AlGaN with a first Al composition ratio higher than an Al composition ratio of the well layer; and a p-type cladding layer being located on the electron blocking layer, comprising AlGaN with a second Al composition ratio higher than the Al composition ratio of the well layer and lower than the first Al composition ratio, and being doped with a predetermined concentration of a p-type dopant. An interface between the electron blocking layer and the p-type cladding layer is doped with not less than a predetermined amount of an n-type dopant.

Abstract: A semiconductor light-emitting element includes: an n-type semiconductor layer made of an n-type AlGaN-based semiconductor material; an active layer made of an AlGaN-based semiconductor material provided on the n-type semiconductor layer; a p-type semiconductor layer provided on the active layer; a p-side contact electrode made of Rh and in contact with the p-type semiconductor layer; a p-side electrode covering layer made of TiN that covers the p-side contact electrode; a dielectric protective layer that covers the n-type semiconductor layer, the active layer, the p-type semiconductor layer, and the p-side electrode covering layer; and a p-side pad electrode in contact with the p-side electrode covering layer in a p-side opening that extends through the dielectric protective layer on the p-side contact electrode.

Abstract: The semiconductor light-emitting element has an n-type semiconductor layer; an active layer provided on a first upper surface of the n-type semiconductor layer; a p-type semiconductor layer provided on the active layer; a p-side contact electrode provided in contact with the upper surface of the p-type semiconductor layer; a p-side current diffusion layer provided on the p-side contact electrode in a region narrower than a formation region of the p-side contact electrode; a p-side pad electrode provided on the p-side current diffusion layer; an n-side contact electrode provided in contact with a second upper surface of the n-type semiconductor layer; an n-side current diffusion layer provided on the n-side contact electrode over a region wider than a formation region of the n-side contact electrode, and including a TiN layer; and an n-side pad electrode provided on the n-side current diffusion layer.

Abstract: The semiconductor light-emitting element includes an n-type semiconductor layer; an active layer on the n-type semiconductor layer; a p-type semiconductor layer on the active layer; a p-side contact electrode in contact with the p-type semiconductor layer; a p-side current diffusion layer on the p-side contact electrode; an n-side contact electrode in contact with the n-type semiconductor layer; and an n-side current diffusion layer that includes a first current diffusion layer on the n-side contact electrode, and a second current diffusion layer on the first current diffusion layer, and including a TiN layer. A height difference between upper surfaces of the p-side contact electrode and the first current diffusion layer is 100 nm or smaller; and a height difference between upper surfaces of the p-side current diffusion layer and the second current diffusion layer is 100 nm or smaller.

Abstract: A semiconductor light-emitting element includes: an n-type semiconductor layer made of an n-type AlGaN-based semiconductor material; an active layer provided on a first upper surface of the n-type semiconductor layer and made of an AlGaN-based semiconductor material; a p-type semiconductor layer provided on the active layer; an n-side contact electrode that includes a Ti layer in contact with a second upper surface of the n-type semiconductor layer, an Al layer provided on the Ti layer, and a nitride layer that covers the Al layer. The nitride layer includes a first portion made of TiN and a second portion containing TiAlN.

Abstract: A semiconductor light emitting element includes: an n-type semiconductor layer made of an n-type aluminum gallium nitride (AlGaN)-based semiconductor material provided on a substrate; an active layer made of an AlGaN-based semiconductor material provided on the n-type semiconductor layer; a p-type semiconductor layer provided on the active layer; and a covering layer made of a dielectric material that covers the n-type semiconductor layer, the active layer, and the p-type semiconductor layer. Each of the active layer and the p-type semiconductor layer has a sloped surface that is sloped at a first angle with respect to the substrate and is covered by the covering layer. The n-type semiconductor layer has a sloped surface that is sloped at a second angle larger than the first angle with respect to the substrate and is covered by the covering layer.

Abstract: A semiconductor light-emitting element includes: an n-type semiconductor layer; an active layer; a p-side contact electrode made of Rh; a p-side electrode covering layer made of Ti or TiN that covers the p-side contact electrode; a first protective layer made of SiO2 or SiON that covers an upper surface and a side surface of the p-side electrode covering layer in a portion different from that of a first p-side pad opening; a second protective layer made of Al2O3 that covers the first protective layer, a side surface of a p-side semiconductor layer, and a side surface of the active layer in a portion different from that of a second p-side pad opening; and a p-side pad electrode that is in contact with the p-side electrode covering layer in the first p-side pad opening and the second p-side pad opening.

Abstract: A semiconductor light-emitting element has an n-type semiconductor layer arranged on a base layer, and is made of an n-type AlGaN-based semiconductor material; an active layer arranged on the n-type semiconductor layer, and is made of an AlGaN-based semiconductor material; a p-type semiconductor layer arranged on the active layer; a p-side contact electrode that contacts the top face of the p-type semiconductor layer; a dielectric protective layer that covers the p-side contact electrode, contacts the top face of the p-type semiconductor layer, and is made of SiO2; and a dielectric cover layer that contacts the individual side faces of the active layer and the p-type semiconductor layer, contacts the top face of the p-type semiconductor layer, covers the dielectric protective layer, and is made of Al2O3.

Abstract: The semiconductor light-emitting element includes an n-type semiconductor layer; an active layer on the n-type semiconductor layer; a p-type semiconductor layer on the active layer; a p-side contact electrode in contact with the p-type semiconductor layer; a p-side current diffusion layer on the p-side contact electrode; an n-side contact electrode in contact with the n-type semiconductor layer; and an n-side current diffusion layer that includes a first current diffusion layer on the n-side contact electrode, and a second current diffusion layer on the first current diffusion layer, and including a TiN layer. A height difference between upper surfaces of the p-side contact electrode and the first current diffusion layer is 100 nm or smaller; and a height difference between upper surfaces of the p-side current diffusion layer and the second current diffusion layer is 100 nm or smaller.

Abstract: A semiconductor light-emitting element includes: an n-type semiconductor layer; an active layer; a p-side contact electrode made of Rh; a p-side electrode covering layer made of Ti or TiN that covers the p-side contact electrode; a first protective layer made of SiO2 or SiON that covers an upper surface and a side surface of the p-side electrode covering layer in a portion different from that of a first p-side pad opening; a second protective layer made of Al2O3 that covers the first protective layer, a side surface of a p-side semiconductor layer, and a side surface of the active layer in a portion different from that of a second p-side pad opening; and a p-side pad electrode that is in contact with the p-side electrode covering layer in the first p-side pad opening and the second p-side pad opening.

Abstract: A method of manufacturing a semiconductor light emitting element includes: forming an active layer made of an aluminum gallium nitride (AlGaN)-based semiconductor material on an n-type clad layer made of an n-type AlGaN-based semiconductor material; removing a portion of each of the active layer and the n-type clad layer by dry etching to expose a portion of the n-type clad layer; forming a first metal layer including titanium (Ti) on an exposed surface of the n-type clad layer; forming a second metal layer including aluminum (Al) on the first metal layer; and forming an n-side electrode by annealing the first metal layer and the second metal layer at a temperature not lower than 560° C. and not higher than 650° C. A film density of the second metal layer before the annealing is lower than 2.7 g/cm3.

Abstract: A semiconductor light-emitting element includes: an n-type semiconductor layer made of an n-type AlGaN-based semiconductor material; an active layer provided on the n-type semiconductor layer and made of an AlGaN-based semiconductor material; a p-type semiconductor layer provided on the active layer; a p-side contact electrode that includes a Rh layer in contact with an upper surface of the p-type semiconductor layer; and a p-side current diffusion layer that is in contact with an upper surface and a side surface of the p-side contact electrode and includes a TiN layer, a Ti layer, a Rh layer, and a TiN layer stacked successively. A film density of the Rh layer included in the p-side contact electrode is larger than a film density of the Rh layer included in the p-side current diffusion layer.

Abstract: A semiconductor light-emitting element includes: an n-type semiconductor layer made of an n-type AlGaN-based semiconductor material; an active layer provided on the n-type semiconductor layer and made of an AlGaN-based semiconductor material; a p-type semiconductor layer provided on the active layer; a p-side contact electrode that includes a Rh layer in contact with an upper surface of the p-type semiconductor layer; and a p-side current diffusion layer that is in contact with an upper surface and a side surface of the p-side contact electrode and includes a TiN layer, a Ti layer, a Rh layer, and a TiN layer stacked successively. An Ar concentration in the Rh layer included in the p-side contact electrode is smaller than an Ar concentration in the Rh layer included in the p-side current diffusion layer.

Abstract: A semiconductor light-emitting element includes: an n-type semiconductor layer made of an n-type AlGaN-based semiconductor material; an active layer provided on the n-type semiconductor layer and made of an AlGaN-based semiconductor material; a p-type semiconductor layer provided on the active layer; a p-side contact electrode that includes a Rh layer in contact with an upper surface of the p-type semiconductor layer; a p-side electrode covering layer that is in contact with an upper surface and a side surface of the p-side contact electrode and includes a Ti layer, a Rh layer, and a TiN layer stacked successively; a dielectric covering layer that has a connection opening provided on the p-side electrode covering layer and covers the p-side electrode covering layer in a portion different from the connection opening; and a p-side current diffusion layer that connects to the p-side electrode covering layer in the connection opening.

Abstract: A deep ultraviolet light emitting device includes: an electron block layer of a p-type AlGaN-based semiconductor material or a p-type AlN-based semiconductor material provided on a support substrate; an active layer of an AlGaN-based semiconductor material provided on the electron block layer; an n-type clad layer of an n-type AlGaN-based semiconductor material provided on the active layer; an n-type contact layer provided on a partial region of the n-type clad layer and made of an n-type semiconductor material containing gallium nitride (GaN); and an n-side electrode formed on the n-type contact layer. The n-type contact layer has a band gap smaller than that of the n-type clad layer.

Abstract: A semiconductor light emitting device includes a light extraction layer having a light extraction surface. The light extraction layer includes: a plurality of cone-shaped parts formed in an array on the light extraction surface, and a plurality of granular parts formed both on a side part of the cone-shaped part and in a space between adjacent cone-shaped parts. A method of manufacturing the semiconductor light emitting device includes: forming a mask having an array pattern on the light extraction layer; and etching the mask and the light extraction layer from above the mask. The etching includes first dry-etching performed until an entirety of the mask is removed and second dry-etching performed to further dry-etch the light extraction layer after the mask is removed.