Patent ID: 9520538
Filing Date: 2016-12-13
CPC Classification: H01L

Claim Text:
1. An LED epitaxial structure, from bottom to up, comprising: a substrate; a GaN nucleating layer; a superlattice buffer layer comprising a plurality pairs of alternately stacked AlGaN/GaN structures; an n-type GaN layer; a MQW light-emitting layer, a p-type GaN layer, and a p-type contact layer; wherein an Al composition value of an n th AlGaN/GaN superlattice buffer layer pair is represented by Al(n); an n-type impurity concentration value of the n th AlGaN/GaN superlattice buffer layer pair is represented by N(n); a variation trend of Al(n) is from gradual increase to gradual decrease, and a variation trend of N(n) is from gradual increase to gradual decrease.