PURPOSE: To prevent the deposition of solid material at the outlet end of a reaction gas introducing line, and to form a uniform glass layer, by using a multi- walled pipe as the pipe for introducing a reaction gas, supplying a raw material through the core pipe, and ejecting a gas from the outermost section to scatter the deposit.
CONSTITUTION: An oxygen plasma flame is generated by supplying oxygen to a high-frequency plasma torch 1 as shown in the figure as the arrows. A double- walled pipe 2 for the supply of a reaction gas is placed close to the plasma torch 1. SiCl4 and CCl2F2 are introduced into the reaction chamber 4 through the core tube of the reaction gas introducing pipe 2 using oxygen gas as the carrier gas, and N2 gas is introduced into the chamber 4 through the outer section of the double-walled pipe. SiCl4 is made to react with CCl2F2 to deposit an F-doped SiO2 glass layer 7 on the target rod 6. Since the deposition of a solid material to the outlet end of the gas introducing pipe 2 is inhibited by the N2 gas blasted through the outer section, a uniform glass layer 7 can be produced.
TERAOKA TATSUO
FUJITA NOBUYOSHI
| JPS56104738A | 1981-08-20 | |||
| JPS5224217A | 1977-02-23 |