Abstract: A nitride semiconductor element includes a sapphire substrate including: a main surface extending in a c-plane of the sapphire substrate, and a plurality of projections disposed at the main surface, the plurality of projections including at least one projection having an elongated shape in a plan view; and a nitride semiconductor layer disposed on the main surface of the sapphire substrate. The at least one projection has an outer edge extending in a longitudinal direction of the elongated shape, the outer edge extending in a direction oriented at an angle in a range of ?10° to +10° with respect to an a-plane of the sapphire substrate in the plan view.

Abstract: A light-emitting element includes: a sapphire substrate including: a principal surface that is in a c-plane of the sapphire substrate, and a plurality of projections on the principal surface, wherein each of the plurality of projections has a shape of pseudo-hexagonal pyramid including six lateral surfaces, each of the six lateral surfaces including an inwardly curved surface portion, and wherein, in a top view of the sapphire substrate, each of the plurality of projections has a shape of a pseudo-hexagon; and a semiconductor layered body comprising a nitride semiconductor on the principal surface side of the sapphire substrate, the semiconductor layered body including an active layer.

Abstract: A light-emitting element includes: a sapphire substrate including: a principal surface that is in a c-plane of the sapphire substrate, and a plurality of projections on the principal surface, wherein each of the plurality of projections has a shape of pseudo-hexagonal pyramid including six lateral surfaces, each of the six lateral surfaces including an inwardly curved surface portion, and wherein, in a top view of the sapphire substrate, each of the plurality of projections has a shape of a pseudo-hexagon; and a semiconductor layered body comprising a nitride semiconductor on the principal surface side of the sapphire substrate, the semiconductor layered body including an active layer.

Abstract: A light-emitting element includes a sapphire substrate including: a principal surface that is in a c-plane of the sapphire substrate, and a plurality of projections on the principal surface, wherein each of the plurality of projections has a shape of pseudo-hexagonal pyramid including six lateral surfaces, each of the six lateral surfaces including an inwardly curved surface portion, and wherein, in a top view of the sapphire substrate, each of the plurality of projections has a shape of a pseudo-hexagon that includes first curved lines and second curved lines that are alternately connected to one another, the first curved lines being curved toward a center of a corresponding hexagon and disposed between respective adjacent pairs of six vertices of the hexagon, and the second curved lines passing through respective vertices of the hexagon; and a semiconductor layered body comprising a nitride semiconductor on the principal surface side of the sapphire substrate, the semiconductor layered body including an act

Abstract: A nitride semiconductor element includes a sapphire substrate including: a main surface extending in a c-plane of the sapphire substrate, and a plurality of projections disposed at the main surface, the plurality of projections including at least one projection having an elongated shape in a plan view; and a nitride semiconductor layer disposed on the main surface of the sapphire substrate. The at least one projection has an outer edge extending in a longitudinal direction of the elongated shape, the outer edge extending in a direction oriented at an angle in a range of ?10° to +10° with respect to an a-plane of the sapphire substrate in the plan view.

Abstract: A method of manufacturing a nitride semiconductor element includes dry etching a main surface of a sapphire substrate at a c-plane side thereof, using a mask provided on the main surface, to form a plurality of projections, each having a circular bottom surface; wet etching the sapphire substrate to form an upper part of each projection into a triangular pyramid shape while maintaining the circular bottom surface of the projection; and growing a semiconductor layer made of a nitride semiconductor on a dry etched surface and a wet etched surface of the sapphire substrate.

Abstract: A nitride semiconductor element includes a sapphire substrate including: a main surface extending in a c-plane of the sapphire substrate, and a plurality of projections disposed at the main surface, the plurality of projections including at least one projection having an elongated shape in a plan view; and a nitride semiconductor layer disposed on the main surface of the sapphire substrate. The at least one projection has an outer edge extending in a longitudinal direction of the elongated shape, the outer edge extending in a direction oriented at an angle in a range of ?10° to +10° with respect to an a-plane of the sapphire substrate in the plan view.

Abstract: A light-emitting element includes a sapphire substrate including: a principal surface that is in a c-plane of the sapphire substrate, and a plurality of projections on the principal surface, wherein each of the plurality of projections has a shape of pseudo-hexagonal pyramid including six lateral surfaces, each of the six lateral surfaces including an inwardly curved surface portion, and wherein, in a top view of the sapphire substrate, each of the plurality of projections has a shape of a pseudo-hexagon that includes first curved lines and second curved lines that are alternately connected to one another, the first curved lines being curved toward a center of a corresponding hexagon and disposed between respective adjacent pairs of six vertices of the hexagon, and the second curved lines passing through respective vertices of the hexagon; and a semiconductor layered body comprising a nitride semiconductor on the principal surface side of the sapphire substrate, the semiconductor layered body including an act

Abstract: A method of manufacturing a nitride semiconductor element includes dry etching a main surface of a sapphire substrate at a c-plane side thereof, using a mask provided on the main surface, to form a plurality of projections, each having a circular bottom surface; wet etching the sapphire substrate to form an upper part of each projection into a triangular pyramid shape while maintaining the circular bottom surface of the projection; and growing a semiconductor layer made of a nitride semiconductor on a dry etched surface and a wet etched surface of the sapphire substrate.

Abstract: A method of manufacturing a nitride semiconductor element includes dry etching a main surface of a sapphire substrate at a c-plane side thereof, using a mask provided on the main surface, to form a plurality of projections, each having a circular bottom surface; wet etching the sapphire substrate to form an upper part of each projection into a triangular pyramid shape while maintaining the circular bottom surface of the projection; and growing a semiconductor layer made of a nitride semiconductor on a dry etched surface and a wet etched surface of the sapphire substrate.

Abstract: A nitride semiconductor element includes a sapphire substrate including: a main surface extending in a c-plane of the sapphire substrate, and a plurality of projections disposed at the main surface, the plurality of projections including at least one projection having an elongated shape in a plan view; and a nitride semiconductor layer disposed on the main surface of the sapphire substrate. The at least one projection has an outer edge extending in a longitudinal direction of the elongated shape, the outer edge extending in a direction oriented at an angle in a range of ?10° to +10° with respect to an a-plane of the sapphire substrate in the plan view.

Abstract: A method of manufacturing a nitride semiconductor element includes dry etching a main surface of a sapphire substrate at a c-plane side thereof, using a mask provided on the main surface, to form a plurality of projections, each having a circular bottom surface; wet etching the sapphire substrate to form an upper part of each projection into a triangular pyramid shape while maintaining the circular bottom surface of the projection; and growing a semiconductor layer made of a nitride semiconductor on a dry etched surface and a wet etched surface of the sapphire substrate.