Fabrication and investigation of integrated-optics CdSxSe1–x waveguides

The diffusion of selenium in CdS was used to fabricate planar and strip waveguides with losses in the range 3–5 dB/cm at the wavelength of 0.63 μ. A study was made of the influence of the diffusion conditions on the main waveguide parameters. A mathematical model was developed for determining the distribution of the refractive index with depth in a crystal for different diffusion regimes. A single substrate was used to form waveguides with band gaps of 2.41 and 2.47 eV. The coupling efficiency of these waveguides exceeded 90%.