摘要 |
A semiconductor structure is formed of nitrides of group III metals having wurtzite crystal structure and grown in vapor phase on a (0001) oriented semiconductor substrate. The structure comprises a bottom cladding layer, a top cladding layer, and a diffusion region positioned between the cladding layers for diffusing light propagating within the semiconductor structure. The diffuse region has refractive index different from those of the cladding layers and non-flat surfaces for providing light diffusing interfaces between the diffusion region and the cladding layers. According to the invention, the diffusion region comprises a plurality of diffusion layers, compositions and thicknesses of said diffusion layers having been chosen to avoid formation of strain-induced dislocations in the diffusion region, and adjacent diffusion layers having different refractive indices in order to further enhance the diffusion efficiency. |