Heat treatment processing apparatus and cleaning method thereof

摘要

While the interior of a reaction vessel is being deaerated by a first vacuum pump, an inert gas is supplied from an upstream side (reaction gas bottle side) of a flow rate control unit (MFC) to a reaction gas supply pipe. Thus, a reaction gas is substituted with the inert gas. A passageway downstream of the MFC is closed and the interior of the pipe is deaerated from the upstream side through a bypass pipe so that a predetermined degree of vacuum is obtained. Thus, the gas substituting efficiency can be improved. The interior of the reaction vessel and the interior of the reaction gas supply pipe are quickly deaerated without an influence of resistance of the MFC. The inert gas substitution process and the deaerating process are repeated for 10 cycles or more.