Patent ID: 7642543

Claim:
A semiconductor light emitting device comprising: a support substrate; a composite connection layer formed above said support substrate, said composite connection layer including a first connection layer and a second connection layer; a diffusion barrier layer formed above said composite connection layer; a semiconductor lamination structure, including semiconductor active layers, formed above said diffusion barrier layer; and a reflective electrode layer formed between said diffusion barrier layer and said semiconductor lamination structure, wherein: at least one of said first and second connection layers is made of eutectic material; said diffusion barrier layer has a lamination structure including TaN layers sandwiching at least one refractory metal layer made of one or more refractory metal materials of Ta, Ti, Mo, W and TiW or alloy thereof; and a thickness of said TaN layer on a side of said composite connection layer is thinner than a thickness of said TaN layer on a side of said reflective electrode layer and thicker than a thickness of said refractory metal layer.