| 摘要 |
PROBLEM TO BE SOLVED: To provide a gas supply system in which backflow of gas can be prevented when a flow of gas is switched between a gas supply line and a vent line.SOLUTION: There is provided a gas supply system 10 supplying gas required for film deposition processing to a processing vessel 4 performing the film deposition processing. The gas supply system 10 includes: a gas supply line 54 in which a first on-off valve V1 is interposed, and which supplies gas to the processing vessel; a vent line 56 in which a second on-off valve V2 is interposed, and which is branched from the gas supply line; and a valve control section 66 which, when switching a flow of gas from a processing vessel side to a vent line side, controls the second on-off valve to be opened after the lapse of a first predetermined time T1 during which pressure in the gas supply line becomes higher than pressure at the vent line side by bringing the first and second on-off valves into a simultaneously closed state and which, when switching the flow of gas from the vent line side to the processing vessel side, controls the first on-off valve to be opened after binging the first and the second on-off valves into the simultaneously closed state. |
