US 11,687,102 B2
Systems and methods for automatic concentration control
Chia-Lun Chen, Hsinchu (TW); Cheng-Hao Kuo, Hsinchu (TW); and Chung-Hao Hu, Hsinchu (TW)
Assigned to Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu (TW)
Filed on Aug. 1, 2022, as Appl. No. 17/878,435.
Application 17/878,435 is a division of application No. 16/932,012, filed on Jul. 17, 2020, granted, now 11,586,230.
Claims priority of provisional application 62/954,352, filed on Dec. 27, 2019.
Prior Publication US 2022/0365546 A1, Nov. 17, 2022
Int. Cl. G05D 11/13 (2006.01); H01L 21/67 (2006.01); G05D 21/02 (2006.01); G05D 7/06 (2006.01)
CPC G05D 11/135 (2013.01) [G05D 21/02 (2013.01); H01L 21/67017 (2013.01); H01L 21/67023 (2013.01); H01L 21/67253 (2013.01); G05D 7/0635 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A system, comprising:
a plurality of processing tanks (112x) configured to contain a chemical mixture including a first chemical;
a recirculation loop (130) in fluid communication with each of the plurality of processing tanks;
a chemical sensor (238) in fluid communication with the recirculation loop and configured to sense one or more properties of the chemical mixture in each of the plurality of processing tanks;
a plurality of first inlet valves (123x, 124x), each of the first inlet valves coupled between a supply of a first liquid (125/126) and an interior of a respective processing tank of the plurality of processing tanks;
a plurality of outlet valves (143x), each of the outlet valves coupled between a respective processing tank of the plurality of processing tanks and the chemical sensor, the plurality of outlet valves in communication with the recirculation loop;
a pump (32) communicatively coupled with the plurality of outlet valves and a plurality of second inlet valves (144x) of the respective processing tanks and positioned between the plurality of outlet valves (143x) and the plurality of second inlet valves (144x), the pump configured to pump a flow of the chemical mixture from the interior of the plurality of processing tanks through the respective plurality of outlet valves, through the chemical sensor and back into the interior of the plurality of processing tanks through the respective second inlet valves;
a plurality of chemical sensing channels, each of the plurality of chemical sensing channel extending between each of the plurality of processing tanks and the chemical sensor; and
control circuitry communicatively coupled to the chemical sensor and the plurality of first inlet valves, the control circuitry configured to automatically adjust an amount of the first liquid in the chemical mixture by selectively operating the plurality of first inlet valves based on the sensed one or more properties of the chemical mixture and to maintain flow of the chemical mixture through the plurality of processing tanks until the chemical mixture in each of the plurality of processing tanks is homogeneous with the chemical mixture in the other plurality of processing tanks.