| 摘要 |
PROBLEM TO BE SOLVED: To enable cost effective production at a high yield with high performance and high grade by using a clad glass layer sintered at a low temp. on a quartz glass substrate to suppress and prohibit the deformation of core glass waveguides. SOLUTION: The one surface of the quartz glass substrate 1 is formed as a smooth surface and another surface is formed as a fine and rough surface 2. A core glass layer of a refractive index higher than the refractive index of the quartz glass substrate 1 is formed on the resulted smooth surface of the quartz glass substrate. The resulted core glass layer is subjected to pattern formation by using a photolithography technique and reactive etching technique, by which the core glass waveguides 3 are formed. A porous glass layer consisting of glass contg. a dopant is formed by using a flame hydrolysis method on the substrate surface with the resulted core glass waveguides 3. Further, the substrate with the resulted porous glass deposition layer is heated to sinter the porous glass to the transparent clad glass and the clad glass layer 4 embedded with the core glass waveguides 3 is obtd. |
