ABSTRACT
This chapter guides to processing property relationships and to summarize the state of the art of crystalline waveguides. The properties of the waveguides often depend on the specific processing parameters used to produce them. Similar to glass fibers, the optical transmission characteristics of crystalline waveguides are determined by the refractive index distribution. However, crystalline waveguides are often birefringent, unlike glass fiber guides, and these effects must be considered when determining the optical characteristics of the waveguide and designing device structures. Fortunately, with some changes in procedures, several of these processing techniques may be transferable to thin-film device fabrication. The ion-exchange, ion-implantation, and strain-induced waveguides with processing temperatures less than 650 degree delicies are the most likely candidates for integrated optics and optoelectronics. Semiconductor waveguides have been produced by means of diffusion, ion implantation, free carrier reduction, compositional changes, electric fields, and strain effects; but, an inherent problem exists in using some of these techniques to produce semiconductor waveguides.
