Kokusai Electric Corporation

Shin-Etsu Quartz Products Co., Ltd.

Toru Nakada

Hiroyuki Kimura

Shinya Morita

Toru Segawa

There is provided a technique that includes a first annealing step of annealing the reaction tube; a first cleaning step of cleaning an inner surface of the reaction tube, after the first annealing step, with a liquid including a fluorine compound having a first concentration; a first rinsing step of washing away the fluorine compound used in the first cleaning step with pure water; a second annealing step of annealing the reaction tube; a second cleaning step of cleaning the inner surface of the reaction tube, after the second annealing step, with a liquid including a fluorine compound having a second concentration higher than the first concentration; and a second rinsing step of washing away the fluorine compound used in the second cleaning step with pure water.

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Toyama, Japan

Toru Nakada