Waveguide devices have been produced comprising germania-doped silica cores and silica claddings on silica substrates, using microwave plasma assisted chemical vapor deposition and reactive-ion etching. This all-silica structure offers the maximum compatibility between fibers and waveguides in terms of both optical and physical properties. The all-silica philosophy is extended to the use of laser-cut silica V grooves in the construction of input/output fiber arrays. An important feature of this approach is that it enables fiber/waveguide interfacing by CO2 laser welding of the respective silica blocks without the introduction of any significant additional loss. Both the waveguide fabrication and laser-welding processes are well suited to large-scale production of low-cost components.
James J. G. Allen,
Simon P. Shipley,
"Silica-based integrated optic components for telecommunications applications," Optical Engineering 32(5), (1 May 1993). https://doi.org/10.1117/12.133293