Further, the n-side buffer layer is that is grown at a high temperature and is distinguished from a buffer layer having a thickness of 0.5 ??m or less which is grown at a low temperature of 900??? C. or less directly on the substrate made of the material, such as sapphire, SiC and spinel, which is different from nitride semiconductors. [0302] (n-Side Cladding Layer 14=Superlattice Layer) [0303] Su