PRODUCTION OF OPTICAL WAVEGUIDE

摘要

PROBLEM TO BE SOLVED: To easily produce an optical waveguide having a core region of a desired width (more particularly a very fine width). SOLUTION: A glass film for the core is formed on a glass layer by a step S10 and an etching mask is formed on the glass film for the core by steps S11 and S12. The glass film for the core is etched by gaseous c-C4 F8 via the etching mask and the core region is formed by a step S13. At the time of the etching, the gaseous c-C4 F8 is cracked and C2 F4 which is radical species is formed. The polymerized film of the C2 F4 is adhered to the flank of the core region as well. The polymerized film acts also as a protective film against etching.