PROCESS FOR DIRECT LASER MICROMACHINING OF OPTICAL WAVEGUIDES AND OPTICAL WAVEGUIDES PRODUCED THEREBY

摘要

The present invention is concerned with a process for fabricating a ridge waveguide, and an optical waveguide comprising this ridge waveguide. More specifically, the ridge waveguide is fabricated from an optical waveguide made of superposed cladding layer, core layer and, possibly, a buffer layer. By modifying two laterally adjacent strips of the optical waveguide from the outer surface of the cladding layer, a ridge waveguide is formed between these two modified strips. The modification can be made by direct laser micromachining two trenches in the optical waveguide. In one embodiment, the modified strips or trenches extend from the outer surface of the cladding layer and at least throughout the thickness of the cladding layer and at most throughout the thickness of the cladding layer and a part of the thickness of the core layer. In another embodiment, the trenches extend at least throughout the thickness of the cladding layer and can dig throughout the core layer. Advantageously, the trenches will present a Gaussian profile.