| 摘要 |
A gas dividing/supplying apparatus includes a pressure-type flow control system, a plurality of divided flow passages 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, thermal-type mass flow sensors disposed in the divided flow passages, respectively, motor-operated valves disposed on a downstream side of the thermal-type mass flow sensors, respectively, and switching-type controllers that control opening and closing of the motor-operated valves, respectively, and, in the apparatus, the switching-type controllers perform switching between valve opening control for maintaining the 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 motor-operated valves by feedback control based on a flow detection signal of the thermal-type mass flow sensor by a divided flow control command signal. |
| 主权项 |
1. A method for dividing and supplying gas, wherein the method comprises:
providing an apparatus for dividing and supplying gas comprising,
(a) a pressure-type flow control system arranged to control a total flow quantity (Q) of a gas supplied to a process chamber,(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 the 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 in response to a valve opening control command signal (Sp), 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 (Sm) provided by the plurality of thermal-type mass flow sensors and a divided flow control command signal (Ss),wherein the motor-operated valves are configured such that the opening degree of each of the motor-operated valves is maintained at the predetermined fixed opening degree through the corresponding switching-type controller before the pressure-type flow control system operates, andwherein upon switching from valve opening control to divided flow control, the flow of gas is controlled to the total flow quantity (Q) by the pressure-type flow control system; subjecting the opening degree of each of the plurality of the motor-operated valves to feedback control based on a respective flow detection signal emitted from a corresponding one of the plurality of thermal-type mass flow sensors through the respective switching-type controller when flow control of the total flow quantity of gas is performed by operation of the flow control system; and supplying divided flow quantities of gas that are set-flow quantities through the plurality of divided flow passages, wherein the number of the plurality of divided flow passages falls within a range of two to four, and a valve opening degree of each motor-operated valve during the valve opening control is set at 40% to 70% of the fully opened state of the valve, and wherein a control switching unit is provided to receive input of a control switching signal (Sx) either from a valve opening control unit or the pressure-type flow control system to output the divided flow control command signal (Ss). |
