LIGHT EMITTING DEVICE AND LIGHTING SYSTEM

摘要

A light emitting element of an embodiment includes: a substrate having an uneven structure with multiple protrusions formed at least on a partial surface; a first conductive semiconductor layer on the substrate; an active layer on the first conductive semiconductor layer; a second conductive semiconductor layer on the active layer; a first electrode on the second conductive semiconductor layer; and a second electrode formed in an exposed area of the first conductive semiconductor layer. The length (w) of the bottom side of the protrusions is 0.9-1.3um and the height (h) thereof is 0.65-0.8um. A gap between adjacent protrusions is 0.3-0.33um. An embodiment provides a light emitting element, capable of improving the efficiency of the light extraction of the light emitting element by reducing a light absorption factor of the substrate. Moreover, the uneven structure of the substrate smoothens a charge flow in the semiconductor layers to improve an electric property.