Optical Waveguides Based on Sol-Gel Coatings

This chapter focuses on developing coatings for use as waveguides for integrated optics and photonics. Thin (or thick) films of silica-based inorganic materials and organic-inorganic hybrids can be easily obtained using the sol-gel and spin-coating method, followed by rapid thermal annealing to obtain dense films of good optical quality. The waveguide thermal, structural, and optical properties can be characterized using differential thermal analysis, X-ray diffraction, Fourier-transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, and atomic force microscopy. Waveguides can be both doped with semiconductor microcrystallites and rare-earths for the development of optical devices, where light is confined to one or two dimensions (planar, channel or strip loaded)