Patent ID: 6608328
Filing Date: 2003-08-19
Classification: H01L,Y10S

Abstract:
A light emitting diode comprising:a bottom electrode contact; a GaAs substrate of first conductivity on said bottom electrode contact; a GaAs buffer layer on said GaAs substrate; a first InGaAlP layer on said GaAs buffer layer; an active layer on said first InGaAlP layer; a second InGaAlP layer of second conductivity opposite to said first conductivity on said active layer; a light extraction layer on said second InGaAlP layer, wherein said light extraction layer blocks and spreads currents from said second InGaAlP layer, and said light extraction layer comprises a current blocking layer on said second InGaAlP layer, wherein said current blocking layer comprises a In0.5(Ga1âˆ’xAlx)0.5P layer of said second conductivity and thickness of said current blocking layer is about 10-100 nm; a lattice gradient layer on said current blocking layer to accommodate the difference in lattice constant between said current blocking layer and subsequent layer; and a window layer on said lattice gradient layer for the current spreading in said light emitting diode; and a top electrode contact layer on said light extraction layer.