Patent ID: 7098484

Claim:
An epitaxial substrate for a compound semiconductor light-emitting device comprising: a double-hetero light-emitting layer structure including a pn junction; and a p-type layer side layer structure formed in contact with the light-emitting layer structure including in order from the layer in contact with the light-emitting layer structure an n-type first layer represented by In x Al y Ga z N (x+y+z=1, 0≦x≦1, 0≦y≦1,0z≦1), an n-type second layer represented by In u Al v Ga w N (u+v+w=1, 0≦u≦1, 0≦v≦1, 0≦w≦a p-type third layer represented by In p Al q Ga r N (p+q+r=1, 0≦p≦1, 0≦q≦1, 0≦r≦1), each of the three neighbors being formed in contact with its neighbor, wherein the n-type second layer has a p-type dopant.