Gas supply system

Abstract

A gas supply system is provided. The system includes a plurality of component gas supply pipes, a plurality of flow rate control mechanisms for controlling flow rates of the component gases flowing in the component gas supply pipes, and a material gas supply pipe connected with downstream ends of the component gas supply pipes, and connected with one of the gas supply ports at a downstream. The flow rate control mechanism includes flow rate control valves, individual pressure sensors, and fluid resistance elements provided to the component gas supply pipes in this order from upstream, respectively, a common pressure sensor, and controllers for calculating the flow rates of the gases flowing in the component gas supply and controlling the flow rate control valves of the corresponding component gas supply pipes so that the calculated component gas flow rate approaches a predetermined gas flow rate, respectively.

1 . A gas supply system comprising:
 a plurality of gas supply devices each connected to a respective plurality of gas supply ports formed in a device manufacturing chamber, each of the gas supply devices being configured to supply a material gas composed of a plurality of component gases to the gas supply ports;   wherein each of the gas supply devices includes:
 a plurality of component gas supply pipes, each configured to flow a respective component gas, the component gases collectively forming a material gas flow; 
 a plurality of flow rate control mechanisms, each flow rate control mechanism being configured to control a flow rate of the component gas flowing in a respective component gas supply pipe; and 
 a material gas supply pipe connected at an upstream end thereof with downstream ends of the plurality of component gas supply pipes, and connected at a downstream end thereof with one of the component gas supply ports; and 
   wherein each flow rate control mechanism includes:
 a fluid resistance element, an individual pressure sensor, and a flow rate control valve provided on the corresponding component gas supply pipe in this order from upstream to downstream, respectively; 
 a common pressure sensor provided either in a common supply pipe or in one of the component gas supply pipes upstream of the fluid resistance element for that component gas supply pipe, the common supply pipe being a bundle of upstream end parts of the component gas supply pipes where a same kind of component gas flows; and 
 a controller configured to calculate the flow rates of each of the component gases flowing in each of the component gas supply pipes based on respective pressures measured by the corresponding individual pressure sensors of each of the component gas supply pipes, and further based on a pressure measured by the common pressure sensor, the controller also being configured to control each of the flow rate control valves of the corresponding component gas supply pipes so that the calculated component gas flow rate for each of the respective component gas supply pipes approach a predetermined gas flow rate. 
   
     
     
         2 . A gas supply system comprising:
 a plurality of gas supply devices each connected to a respective plurality of gas supply ports formed in a device manufacturing chamber, each of the gas supply devices being configured to supply a material gas composed of a plurality of component gases to the gas supply ports;   wherein each of the gas supply devices includes:
 a plurality of component gas supply pipes, each configured to flow a respective component gas, the component gases collectively forming a material gas flow; 
 a plurality of flow rate control mechanisms, each flow rate control mechanism being configured to control a flow rate of the component gas flowing in a respective component gas supply pipe; and 
 a material gas supply pipe connected at an upstream end thereof with downstream ends of the plurality of component gas supply pipes, and connected at a downstream end thereof with one of the component gas supply ports; and 
   wherein each flow rate control mechanism includes:
 a fluid resistance element and an individual pressure sensor provided on the corresponding component gas supply pipe in this order from upstream to downstream, respectively; 
 a common pressure sensor provided either in a common supply pipe or in one of the component gas supply pipes upstream of the fluid resistance element for that component gas supply pipe, the common supply pipe being a bundle of upstream end parts of the component gas supply pipes where a same kind of component gas flows; and 
 a calculator configured to calculate the flow rates of each of the component gases flowing in each of the component gas supply pipes based on respective pressures measured by the corresponding individual pressure sensors of each component gas supply pipes, and further based on a pressure measured by the common pressure sensor.