Ultraviolet light emitting devices

An ultraviolet light emitting device, comprising:

• a substrate provided with a concave or convex edge pattern at side edges of an upper surface thereof, wherein an inner region excluding the side edges in the upper surface has a flat surface;
• a semiconductor laminate including a first conductivity-type AlGaN semiconductor layer, an active layer having an AlGaN quantum well, and a second conductivity-type AlGaN semiconductor layer that are sequentially disposed on the upper surface of the substrate and on the edge pattern;
• and
• a plurality of cleavages extending from the edge pattern along a side surface of the semiconductor laminate in a stacking direction of the semiconductor laminate and having shapes of non-uniform lines.

An ultraviolet light emitting device, comprising:

• a substrate having a rectangular parallelepiped structure and provided with an edge pattern disposed at at least one side edge of an upper surface thereof, wherein a region excluding the edge pattern in the upper surface has a flat surface;
• and
• a semiconductor laminate disposed on the upper surface of the substrate and on the edge pattern and having a plurality of gaps on at least one side surface of the semiconductor laminate and connected to the edge pattern, the plurality of gaps extending in non-uniform manner from the edge pattern in a stacking direction of the semiconductor laminate,
• wherein the semiconductor laminate has an AlN base layer, a first conductivity-type AlGaN semiconductor layer, an active layer having an AlGaN quantum well, and a second conductivity-type AlGaN semiconductor layer that are sequentially grown on the upper surface of the substrate.