Patent ID: 6903364

Claim:
A light emitting device comprising: a certain conduction type of a GaN first cladding layer, an In 1-x-t-y1 Ga x1 Al y1 N second cladding layer of said certain conduction type, an In 1-x2-y2 Ga x2 Al y2 N active layer, an opposite conduction type of an In 1-x3-y3 Ga x3 Al y3 N third cladding layer, an opposite conduction type of GaN fourth cladding layer, all successively formed one upon each other, wherein x1, x2, x3 define the gallium mole fraction, y1, y2 and y3 define the aluminum mole fraction, and x1, y1, x2, y2, x3 and y3 have a relationship of 0<=x1+y1<=1, 0<x2+y2<1,0<=x3+y3<=1, 1<=x1/0.80+y1/0.89, 1<=x2/0.80+y2/0.89, 1<=x3/0.80+y3/0.89, and Eg InN (1-x1-y1)+Eg GaN x1+Eg AlN y1=Eg InN (1-x2-y2)+Eg GaN x2+Eg AlN y2, Eg InN (1-x3-y3)+Eg GaN x3 +Eg AlN y3>Eg InN (1-x3-y3)+Eg GaN x3+Eg AlN y3 where Eg InN , Eg GaN , and Eg AlN are the bandgap energy of InN, GaN, and AlN, respectively.