Systems and methods that use infrared (IR) spectroscopy to monitor process chemicals utilized in a semiconductor process

A method to monitor process chemicals used in a semiconductor process, the method comprising:

• dispensing a liquid onto a surface of a substrate, wherein the liquid dispensed onto the surface of the substrate comprises a liquid photoresist material;
• monitoring the liquid before the liquid is dispensed onto the surface of the substrate, wherein said monitoring comprises:
• transmitting infrared (IR) radiation through the liquid;
• detecting the IR radiation absorbed by the liquid at one or more wavelengths;
• and
• detecting a composition and a concentration of at least one process chemical included within the liquid based on the IR radiation detected at the one or more wavelengths, wherein said detecting comprises detecting a concentration of water (H2O) in the liquid photoresist material based on the IR radiation detected at 1450 nm and/or 1950 nm;
• and
• controlling at least one process step performed on the substrate based on the composition or the concentration of the at least one process chemical detected within the liquid.

A method to monitor and control water contamination in a semiconductor process used to process a substrate, the method comprising:

• dispensing a liquid photoresist material onto a surface of the substrate;
• monitoring the liquid photoresist material before the liquid photoresist material is dispensed onto the surface of the substrate to coat the surface of the substrate with the liquid photoresist material, wherein said monitoring comprises:
• transmitting infrared (IR) radiation through the liquid photoresist material;
• detecting the IR radiation absorbed by the liquid photoresist material at one or more wavelengths;
• and
• detecting a concentration of water (H2O) in the liquid photoresist material based on the IR radiation detected at 1450 nm and/or 1950 nm;
• and
• controlling at least one process step performed on the substrate based on the concentration of water detected in the liquid photoresist material.