| 摘要 |
PROBLEM TO BE SOLVED: To highly accurately perform the diversion supply of process gas from one gas supply source to a plurality of process chambers which simultaneously perform the same process in parallel while performing flow rate control.SOLUTION: The gas diversion supply device includes: a control valve 3 connected to a gas inlet 11; a gas supply main pipe 8 and an orifice 6 communicating with the downstream; a plurality of branch conduits 9a and 9n and branch conduit opening/closing valves 10a and 10n connected in parallel with the downstream of the gas supply main pipe; a pressure sensor 5 of a passage between the control valve and the orifice; and an arithmetic control unit 7 for calculating the total flow rate Q of gas which circulates through the orifice, outputting a signal Pd for operating the opening/closing of the control valve in a direction in which a difference between the calculated flow rate value and a set flow rate value is decreased to a valve driving part 3a, and outputting signals Od1 and Odn for successively opening and then closing each branch conduit opening/closing valve only in a fixed time. The flow rate control of gas which circulates through the orifice is performed by a pressure type flow rate control part 1a, and the diversion supply of gas is performed in accordance with the opening/closing of the branch conduit opening/closing valve. |
