| 摘要 |
PROBLEM TO BE SOLVED: To detect failure of a supply valve connected with a cooling gas line for supplying wafer cooling gas, in a semiconductor production apparatus having a wafer cooling system.SOLUTION: Exhaust valves VB1, VB2 opening and closing alternately, and a needle valve NB capable of squeezing the amount of exhaust of the wafer cooling gas are connected with a first exhaust line connected with the cooling gas line between a mass flow controller MFC and a pressure meter PM. Upon failure of a supply valve GB connected with the cooling gas line, a pressure reduction sequence corresponding internal leakage, or the like, of the mass flow controller MFC operates so that the pressure measured by the pressure meter PM does not become a set value, by squeezing the amount of exhaust through the needle valve NB, even if the wafer cooling gas is exhausted to a discharge pump DP through the first exhaust line, thereby reducing the pressure within a non-monitoring time. |
