Patent ID: 8890194

Claim:
A semiconductor light emitting device, comprising: a metal substrate having a coefficient of thermal expansion not more than 10×10 −6 m/K; a first semiconductor layer of a first conductivity type including a nitride semiconductor; a second semiconductor layer of a second conductivity type provided between the metal substrate and the first semiconductor layer, the second semiconductor layer including a nitride semiconductor; a light emitting layer provided between the first semiconductor layer and the second semiconductor layer, the light emitting layer including a nitride semiconductor; a first intermediate layer provided between the metal substrate and the second semiconductor layer to contact the metal substrate; and a second intermediate layer provided between the first intermediate layer and the second semiconductor layer, a surface roughness of a first surface of the metal substrate contacting the first intermediate layer being less than a thickness of the first intermediate layer, wherein the metal substrate has a second surface on a side opposite to the first surface, and a surface roughness of the second surface is greater than the surface roughness of the first surface.