LIGHT EMITTING DIODE AND MANUFACTURING METHOD THEREOF

摘要

A light emitting diode includes a substrate, a transitional layer on the substrate and an epitaxial layer on the transitional layer. The transitional layer includes a planar area with a flat top surface and a patterned area with a rugged top surface. An AlN material includes a first part consisting of a plurality of spheres and a second part consisting of a plurality of slugs. The spheres are on a top surface of the transitional layer, both at the planar area and the patterned area. The slugs are in grooves defined in the patterned area. Air gaps are formed between the slugs and a bottom surface of the epitaxial layer. The spheres and slugs of the AlN material help reflection of light generated by the epitaxial layer to a light output surface of the LED.