Liquid chemical tank module and liquid chemical supply apparatus including the same

A liquid chemical supply apparatus comprising:

• a first liquid chemical tank configured to supply a liquid chemical to a substrate processing apparatus for processing a substrate;
• and
• a second liquid chemical tank connected to the first liquid chemical tank through at least one circulation line and configured to circulate the liquid chemical to the first liquid chemical tank and control the liquid chemical to a target temperature suitable for process conditions,
• wherein each of the first and second liquid chemical tanks comprises:
• a tank body having a storage space capable of storing the liquid chemical;
• a gas ejector configured to eject an inert gas into the liquid chemical stored in the storage space to reduce dissolved oxygen in the liquid chemical stored in the storage space of the tank body;
• and
• a controller configured to apply a control signal to the gas ejector to control a flow rate of the inert gas ejected through the gas ejector, and
• wherein the gas ejector comprises:
• a gas pipe extending into the storage space through a surface of the tank body in a height direction of the tank body and at least partially immersed in the liquid chemical stored in the storage space and configured to supply the inert gas from outside of the tank body into the storage space;
• a plurality of ejection nozzles provided at predetermined intervals along an extension direction of the gas pipe and configured to eject the inert gas into the storage space or the liquid chemical stored in the storage space;
• and
• a plurality of level sensors corresponding to the number of the plurality of ejection nozzles, mounted on the gas pipe, and positioned individually adjacent to the plurality of ejection nozzles to sense the liquid chemical.

A liquid chemical tank module comprising:

• a tank body having a storage space capable of storing a liquid chemical;
• a plurality of gas ejectors mounted in the tank body and configured to eject an inert gas into the liquid chemical stored in the storage space to reduce dissolved oxygen in the liquid chemical stored in the storage space of the tank body;
• a sensor configured to sense a level of the liquid chemical stored in the storage space of the tank body;
• and
• a controller configured to apply a control signal to the gas ejectors to control a flow rate of the inert gas ejected through the gas ejectors, based on level information of the liquid chemical received from the sensor,
• wherein the gas ejectors comprise:
• a first gas ejector mounted at a side of the tank body and configured to eject the inert gas into the storage space or the liquid chemical stored in the storage space;
• and
• a second gas ejector mounted at another side of the tank body to face the first gas ejector and configured to eject the inert gas into the storage space or the liquid chemical stored in the storage space,
• wherein the sensor comprises a plurality of level sensors corresponding to the number of a plurality of ejection nozzles, mounted on a gas pipe, and positioned individually adjacent to the plurality of ejection nozzles to sense the liquid chemical,
• wherein the plurality of ejection nozzles comprise:
• a first ejection nozzle provided on the gas pipe at a predetermined height from a bottom surface of the storage space so as to be positioned at a height adjacent to the bottom surface;
• a second ejection nozzle provided above the first ejection nozzle on the gas pipe so as to be spaced apart from the first ejection nozzle by a first interval;
• and
• an nth ejection nozzle provided above an (n−1)th ejection nozzle on the gas pipe so as to be spaced apart from the (n−1)th ejection nozzle by the first interval,
• wherein the plurality of level sensors comprise:
• a first level sensor mounted above the first ejection nozzle on the gas pipe so as to be adjacent to and spaced apart from the first ejection nozzle by a second interval less than the first interval;
• a second level sensor mounted above the second ejection nozzle on the gas pipe so as to be adjacent to and spaced apart from the second ejection nozzle by the second interval;
• and
• an nth level sensor mounted above the nth ejection nozzle on the gas pipe so as to be adjacent to and spaced apart from the nth ejection nozzle by the second interval, and
• wherein the controller is configured to receive the level information of the liquid chemical from the sensor and apply the control signal to the gas ejectors in such a manner that a flow rate of the inert gas ejected through ejection nozzles immersed in the liquid chemical from among the plurality of ejection nozzles is higher than a flow rate of the inert gas ejected through ejection nozzles not immersed in the liquid chemical, and to feedback-control the flow rate of the inert gas ejected through the ejection nozzles immersed in the liquid chemical based on the level information of the liquid chemical in such a manner that a total flow rate of the inert gas ejected through the ejection nozzles immersed in the liquid chemical is constantly maintained regardless of a change in the number of ejection nozzles immersed in the liquid chemical based on a change in the level of the liquid chemical.