Apparatus for dividing and supplying gas and method for dividing and supplying gas by use of this apparatus

An apparatus for dividing and supplying gas, the apparatus comprising:

• (a) a pressure-type flow control system;
• (b) a plurality of divided flow passages that are connected in parallel with each other and through which gas flowing from the pressure-type flow control system is divided and supplied to a process chamber;
• (c) a plurality of thermal-type mass flow sensors disposed in the divided flow passages, respectively;
• (d) a plurality of motor-operated valves disposed on a downstream side of the plurality of thermal-type mass flow sensors respectively;
• and
• (e) a plurality of switching-type controllers that control opening and closing of the plurality of motor-operated valves, respectively;
• wherein the plurality of switching-type controllers perform switching between valve opening control for maintaining the plurality of motor-operated valves at a predetermined fixed valve opening degree based on a valve opening control command signal, and divided flow control for regulating an opening degree of each of the plurality of motor-operated valves by feedback control based on a plurality of flow detection signals provided by the plurality of thermal-type mass flow sensor by a divided flow control command signal.