Formation of light-guiding interconnections in an integrated optical circuit by composite tapered-film coupling.

We demonstrate a new and simple method of forming light-guiding interconnections in an integrated optical circuit. This involves bridging the devices with a thin film having tapered ends that form naturally during the deposition process. Experiments show that there is no specific requirement for the thickness, refractive index, or relative position of the bridging film. A theory of composite waveguides provides an understanding of these interconnections.

Thin organosilicon films for integrated optics.

The continued development of integrated optics is heavily dependent upon the availability of materials that are suitable for the construction of thin-film optical circuitry and devices. We report here an investigation of new films made by an rf discharge polymerization process of organic chemical monomers. We concentrate our discussion on films prepared from vinyltrimethylsilane and hexamethyldisilbxane. These films are smooth, tough, pinhole-free, transparent from 0.4 microm to 0.75 microm, and exhibit very low loss (<0.04 dB/cm) for light-wave propagation. More importantly, experiments demonstrate the possibility of controlling the refractive index of the films either by the mixing of the two monomers before deposition or by chemical treatment after the film is deposited. The use of the prism-film coupler for studying the refractive index of each material is discussed in detail.