Coupling of Single-Mode Optical Fibers to GaAs Waveguides.

摘要

The object of this research contract is to find an efficient method to couple a single-mode optical fiber to a GaAs waveguide at near infrared wavelengths. The general approach chosen is to first fabricate a transitional waveguide. The fiber and the transitional waveguide are then coupled together by the tapered velocity coupling method. Technologies were developed and excellent results have been obtained in using the r.f. sputtering process with a cleaved GaAs mask to step-etch the GaAsP waveguides. This process followed by the r.f. deposition of SiO2 buffer layer and by deposition of either BaO2 glass or AZ1350 waveguiding layer on top of the SiO2 layer has led to very high coupling efficiency (80%) between the primary waveguide and the transition waveguide. Research on the deposition of sodium glass was undertaken to obtain the transition from uniform planar waveguide to channel waveguide. These results demonstrated that highly efficient fiber to thin film waveguide coupling can probably be realized by this method. Additional research is needed in order to demonstrate a complete coupling system. (Author)