Light-emitting devices

Abstract

The invention relates to a light-emitting device. The photoluminescent device consists of: a substrate; a pattern of many small protrusions from the substrate; a first semiconductor layer created on the substrate; an active layer created on the first semiconductor layer; and a second semiconductor layer created on the active layer, in which each of the protrusions including the first layer is created as a single, inseparable part of the substrate and protrudes from the upper surface of the substrate; and the second layer is created on the first layer and is made of a different material than that of the first layer.