Semiconductor light emitting device, nitride semiconductor layer, and method for forming nitride semiconductor layer

摘要

According to an embodiment, a semiconductor light emitting device includes a foundation layer, a first semiconductor layer, a light emitting layer, and a second semiconductor layer. The foundation layer has an unevenness having recesses, side portions, and protrusions. A first major surface of the foundation layer has an overlay-region. The foundation layer has a plurality of dislocations including first dislocations whose one ends reaching the recess and second dislocations whose one ends reaching the protrusion. A proportion of a number of the second dislocations reaching the first major surface to a number of all of the second dislocations is smaller than a proportion of a number of the first dislocations reaching the first major surface to a number of all of the first dislocations. A number of the dislocations reaching the overlay-region of the first major surface is smaller than a number of all of the first dislocations.

主权项

1. A method for forming a nitride semiconductor layer, comprising:
forming a first layer including a nitride semiconductor on a major surface of a substrate using a group III source material and a group V source material, the major surface of the substrate having a substrate unevenness including a substrate protrusion, a substrate recess, and a substrate side portion; and forming a second layer including a nitride semiconductor on the first layer using the group III source material and the group V source material, a proportion of a supply amount of the group V source material to a supply amount of the group III source material in the forming of the first layer being less than a proportion of a supply amount of the group V source material to a supply amount of the group III source material in the forming the second layer, the forming the first layer including causing at least one of dislocations occurring from the substrate recess in the first layer to reach the substrate side portion, and the forming the second layer including planarizing a layer unevenness formed in a surface of the first layer by filling the second layer into the layer unevenness, wherein a height of the substrate unevenness is not less than about 500 nanometers and not more than 3 micrometers, a thickness of the first layer on the substrate recess is not more than the height of the substrate unevenness, and the forming the second layer including forming the second layer on the first layer formed on the substrate recess.