US 12,170,187 B2
Gas supply system, plasma processing apparatus, and gas supply method
Atsushi Sawachi, Miyagi (JP)
Assigned to TOKYO ELECTRON LIMITED, Tokyo (JP)
Filed by Tokyo Electron Limited, Tokyo (JP)
Filed on Jan. 18, 2023, as Appl. No. 18/098,313.
Claims priority of application No. 2022-006593 (JP), filed on Jan. 19, 2022.
Prior Publication US 2023/0230812 A1, Jul. 20, 2023
Int. Cl. H01J 37/32 (2006.01)
CPC H01J 37/32449 (2013.01) [H01J 37/32623 (2013.01); H01J 37/32816 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A gas supply system for supplying a gas into a processing chamber, comprising:
a plurality of gas supply flow paths configured to supply independently a main gas to the processing chamber;
a flow rate control valve disposed in each of the plurality of gas supply flow paths;
an additive gas flow path connected to a downstream side of the flow rate control valve in at least one of the plurality of gas supply flow paths;
a valve for addition disposed in the additive gas flow path; and
a controller for controlling operations of the flow rate control valve and the valve for addition,
wherein the controller executes:
a control of calculating a flow rate of the main gas flowing through each of the plurality of gas supply flow paths;
a control of acquiring a flow rate of an additive gas that flows through the additive gas flow path and is mixed with the main gas flowing through each of the plurality of gas supply flow paths;
a control of calculating a total flow rate of the flow rate of the main gas and the flow rate of the additive gas, in each of the plurality of gas supply flow paths;
a control of calculating an internal pressure of each of the plurality of gas supply flow paths by using the total flow rate calculated in each of the plurality of gas supply flow paths, a first relationship between a previously-acquired gas flow rate and a previously-acquired gas pressure of the main gas, and a second relationship between a previously-acquired gas flow rate and a previously-acquired gas pressure of the additive gas;
a control of calculating a ratio of the internal pressures calculated in each of the plurality of gas supply flow paths; and
a control of proportionally controlling openings of a plurality of the flow rate control valves based on the ratio of the internal pressures.