MANUFACTURE OF OPTICAL WAVEGUIDE

摘要

PROBLEM TO BE SOLVED: To provide a method for efficiently manufacturing an optical waveguide having a glass layer capable of obtaining uniform distribution of concentration of dopant of P and B by adopting a flame accumulation method by bringing a surface temperature of a substrate to a specific value, a flow rate of hydrogen supplied to an oxyhydrogen flame burner to a specific value, and a relative travel speed of the burner and the substrate to a specific value. SOLUTION: A surface temperature of a substrate 1 is properly adjusted within a scope of 500 to 800 deg.C by heating it by a heater arranged in a lower part of a table 10. Glass minute particles are sprayed toward a Si substrate 1 which is one of the substrates together with oxyhydrogen flame from an oxyhydrogen flame burner 11. An amount of hydrogen supplied to the oxyhydrogen flame burner 11 at this time is properly adjusted within a scope of 2 to 8 liters/min. The oxyhydrogen flame burner 11 reciprocates from an outer periphery of the table 10 toward the direction of center. A travel speed of the oxyhydrogen flame burner 11 at this time is adjusted in a scope of 50 to 300 mm/sec.