Substrate Processing System

A substrate processing system comprising:

• a plurality of process vessels capable of accommodating a substrate;
• a source gas supply source;
• a reactive gas supply source provided separately from the source gas supply source;
• a gas supply pipe connected to each of the process vessels, wherein the gas supply pipe comprises:
• a source gas supply pipe wherethrough a source gas supplied from the source gas supply source flows;
• and
• a reactive gas supply pipe wherethrough a reactive gas supplied from the reactive gas supply source flows;
• a first exhauster configured to exhaust inner atmospheres of the plurality of the process vessels;
• a second exhauster provided separately from the first exhauster, configured to exhaust an inner atmosphere of the source gas supply pipe and connected to the source gas supply pipe through a first switching valve;
• a third exhauster provided separately from the first exhauster and the second exhauster, configured to exhaust an inner atmosphere of the reactive gas supply pipe and connected to the reactive gas supply pipe;
• and
• a controller capable of controlling the first switching valve, the first exhauster and the second exhauster to perform:
• (a) processing the substrate by supplying the source gas through the source gas supply pipe to a process vessel among the plurality of the process vessels;
• and
• (b) exhausting the source gas from the source gas supply pipe to the second exhauster while the source gas is not being supplied through the source gas supply pipe to the process vessel.