Abstract: There is provided a Group-III element nitride semiconductor substrate including a first surface and a second surface, in which even when devices to be produced on the first surface are increased in size, variations in device characteristics between the devices in the same substrate are suppressed. A Group-III element nitride semiconductor substrate includes a first surface and a second surface. The Group-III element nitride semiconductor substrate satisfies at least one of the following items (1) to (3): (1) The main surface has a maximum height Wz of a surface waviness profile of 150 nm or less; (2) The main surface has a root mean square height Wq of the surface waviness profile of 25 nm or less; (3) The main surface has an average length WSm of surface waviness profile elements of 0.5 mm or more.

Abstract: There is provided a Group-III element nitride semiconductor substrate including a first surface and a second surface, in which even when devices to be produced on the first surface are increased in size, variations in device characteristics between the devices in the same substrate are suppressed. A Group-III element nitride semiconductor substrate includes a first surface and a second surface. The Group-III element nitride semiconductor substrate satisfies at least one of the following items (1) to (3): (1) The main surface has a maximum height Wz of a surface waviness profile of 150 nm or less; (2) The main surface has a root mean square height Wq of the surface waviness profile of 25 nm or less; (3) The main surface has an average length WSm of surface waviness profile elements of 0.5 mm or more.

Abstract: A base substrate includes a supporting substrate comprising aluminum oxide, and a base crystal layer provided on a main face of the supporting substrate, comprising a crystal of a nitride of a group 13 element and having a crystal growth surface. At lease one of a metal of a group 13 element and a reaction product of a material of the supporting substrate and the crystal of the nitride of the group 13 element is present between the raised part and the supporting substrate. The reaction product contains at least aluminum and a group 13 element.

Abstract: A base substrate includes a supporting substrate and a base crystal layer provided on a main face of the supporting substrate composed of a crystal of a group 13 nitride and having a crystal growth surface. The base crystal layer includes a raised part. A reaction product of a material of the supporting substrate and the crystal of the group 13 nitride, metal of a group 13 element and/or void is present between the raised part and supporting substrate.

Abstract: A base substrate includes a supporting substrate, and a base crystal layer provided on a main face of the supporting substrate, composed of a crystal of a group 13 nitride and having a crystal growth surface. The base crystal layer includes a raised part. A reaction product of a material of the supporting substrate and the crystal of the group 13 nitride, metal of a group 13 element and/or void is present between the raised part and supporting substrate.

Abstract: A base substrate includes a supporting substrate comprising aluminum oxide, and a base crystal layer provided on a main face of the supporting substrate, comprising a crystal of a nitride of a group 13 element and having a crystal growth surface. At lease one of a metal of a group 13 element and a reaction product of a material of the supporting substrate and the crystal of the nitride of the group 13 element is present between the raised part and the supporting substrate. The reaction product contains at least aluminum and a group 13 element.

Abstract: A method for manufacturing a light emitting device includes a) forming a first light confinement layer having a plurality of openings on or above one main surface of an oriented polycrystalline substrate, said oriented polycrystalline substrate including a plurality of oriented crystal grains; b) stacking an n-type layer, an active layer, and a p-type layer; c) forming a second light confinement layer on said first light confinement layer so that said second light confinement layer covers said plurality of first columnar structures and said second columnar structure; d) forming a transparent conductive film on said second light confinement layer; e) forming a pad electrode on said transparent conductive film; and f) forming a cathode electrode electrically connected to ends of said plurality of first columnar structures closer to said oriented polycrystalline substrate.

Abstract: A light emitting device that is inexpensive, is easy to manufacture, and has high light extraction efficiency is provided. The light emitting device includes an oriented polycrystalline substrate, a plurality of columnar light emitting parts, and a light confinement layer. The oriented polycrystalline substrate includes a plurality of oriented crystal grains. The plurality of columnar light emitting parts are discretely located on or above one main surface of the oriented polycrystalline substrate in areas in which there are no crystal defects, and are each a columnar part having a longitudinal direction matching a normal direction of the oriented polycrystalline substrate. The light confinement layer is made of a material having a lower refractive index than a material for the plurality of columnar light emitting parts, and is located on or above the oriented polycrystalline substrate so as to surround the plurality of columnar light emitting parts.

Abstract: A method for manufacturing a light emitting device includes a) forming a first light confinement layer having a plurality of openings on or above one main surface of an oriented polycrystalline substrate, said oriented polycrystalline substrate including a plurality of oriented crystal grains; b) stacking an n-type layer, an active layer, and a p-type layer; c) forming a second light confinement layer on said first light confinement layer so that said second light confinement layer covers said plurality of first columnar structures and said second columnar structure; d) forming a transparent conductive film on said second light confinement layer; e) forming a pad electrode on said transparent conductive film; and f) forming a cathode electrode electrically connected to ends of said plurality of first columnar structures closer to said oriented polycrystalline substrate.

Abstract: A light emitting device that is inexpensive, is easy to manufacture, and has high light extraction efficiency is provided. The light emitting device includes an oriented polycrystalline substrate, a plurality of columnar light emitting parts, and a light confinement layer. The oriented polycrystalline substrate includes a plurality of oriented crystal grains. The plurality of columnar light emitting parts are discretely located on or above one main surface of the oriented polycrystalline substrate in areas in which there are no crystal defects, and are each a columnar part having a longitudinal direction matching a normal direction of the oriented polycrystalline substrate. The light confinement layer is made of a material having a lower refractive index than a material for the plurality of columnar light emitting parts, and is located on or above the oriented polycrystalline substrate so as to surround the plurality of columnar light emitting parts.