To solve problems relevant to a cylindrical member, such as the following: precipitated silicon deposits more easily in its lower part than in its upper part; the whole have to be exchanged when damage on the lower part progresses; the exchange work is not easy; and collection efficiency drops, making the low cost production of silicon difficult.

The inner surface of the cylindrical member 6 is formed by stacking reaction members 6a-6d formed by precipitating silicon 5 by the contact of a silane family gas and spreads downward with inclination. Since silicon 5 precipitated on the upside reaction members scarcely falls down while contacting with the downside reaction members and falls down in-situ in the vertical direction, the damage of the downside reaction members is suppressed, enabling life elongation to be attained. Since only damaged members are required to be exchanged among the reaction members 6a-6d, partial costs can be decreased; and since the exchange can be easily performed in a short time, silicon 5 can be produced at a low cost without decreasing operation rate.