Development Of Dissolved Oxygen Removal System Using Nitrogen Gas Bubbling

It is essentially important to remove the dissolved oxygen (DO) in the ultrapure water for the future ultra-large scale integration (ULSI). We have found the existence of the big driving force for the oxygen diffusion through the material that increases the DO concentration. Based on this finding, we have developed the DO removal system made of a low oxygen permeability material with the nitrogen gas bubbling as a point of use purifier. In this system, the residual DO concentration has reached 0.2 ppb at a gas-liquid ratio of 1.2 m3/m3 that is ten times smaller than the previously reported data. Furthermore, the other impurities in the ultrapure water do not increase after this process.