| 摘要 |
PROBLEM TO BE SOLVED: To form an excellent refractive index modulation pattern in the core of an optical waveguide. SOLUTION: A plane waveguide type optical circuit where an under-clad layer 21, a core layer 20 obtained by patterning an optical waveguide layer 15, and an over-clad layer 22 covering over the core layer 20 or the like are formed on an Si substrate 10 is prepared as an optical circuit being an object where a diffraction grating is to be formed (figure 1 (a) to (c)). By irradiating the plane waveguide type optical circuit with an ultraviolet laser beam 50 through a phase grating mask 30, the diffraction grating 25 is formed in the core layer 20 (figure 1 (d)) by the refractive index modulation pattern. At such a time, the optical circuit is irradiated with the ultraviolet ray under an irradiation condition that reflected light by the base plate 10 being the ultraviolet ray is set to pass through the outside of a grating forming area in the core layer 20. COPYRIGHT: (C)2004,JPO |
