Provided are a structure for an optical device and method of fabricating the same. The structure includes: a light scattering layer producing nanoparticles due to externally provided thermal energy; a protective layer protecting the light scattering layer; and a capping layer disposed between the light scattering layer and the protective layer. As the light scattering layer is formed of nitride-oxide, an energy gap is increased to make the structure suitable for a high-speed electronic circuit, and a desired stoichiometric ratio can be easily obtained. Also, the capping layer prevents crystalline mismatch, thus the non-uniformity of elements is inhibited to maintain a stoichiometric state. As a result, a high-integrated high-speed electronic circuit, which is excellent in uniformity and reproducibility, can be easily embodied.