GAS FLOW MONITORING SYSTEM

摘要

PURPOSE: A gas flow monitoring system is provided to increase the reliability of the system by reinspecting with high accuracy when flow is abnormal. CONSTITUTION: A gas flow monitoring system comprises a first flow monitoring unit(2), a second flow monitoring unit(3), and a control part(4). The first flow monitoring unit is arranged in an upstream passage of a flow controller of an arbitrary process gas line. The second flow monitoring unit is arranged in a discharge passage branched from an upstream passage of a process chamber. The control part makes the first flow monitoring unit normally monitor the flow of the flow controller and makes the second monitoring unit reinspect whether or not the flow controller is normal when the first flow monitoring unit multiply monitor the abnormal flow. [Reference numerals] (4) Control part; (5) Chamber; (6) Device; (AA) Gas A; (BB) Gas B; (CC) Gas C; (DD) Gas D; (EE) Exhaust;