Patent ID: 9136119
Filing Date: 2015-09-15
Classification: H01L

Abstract:
1. A non-polar hetero substrate, comprising: a non-polar base substrate comprising r-surface sapphire; a nitride base layer disposed on the substrate; a first defect reduction layer disposed on the nitride base layer, the first defect reduction layer including a plurality of air gaps and a plurality of flat portions, wherein each of the plurality of flat portions has a hexagonal void form and is connected to a corresponding one of the plurality of air gaps, and wherein the plurality of air gaps are uniformly arranged at a predetermined interval so as to form a light extraction structure, and wherein each of the plurality of air gaps has a substantially asymmetric form having an elongated portion parallel to the flat portion and a protrusion around a center portion of each of the plurality of air gaps; and a nitride semiconductor layer disposed on the first defect reduction layer.