Optimization of Bubble Tube Design for Enhanced Wafer Cleaning Tank Performance

The structural design of bubble tubes plays a crucial role in optimizing the operational efficiency of bubble systems and improving wafer cleanliness in semiconductor cleaning equipment. This study explores the impact of three distinct bubble tube geometries on system performance under identical operating conditions and a fixed number of bubble holes, aiming to identify the optimal configuration. A coupled computational fluid dynamics and population balance model simulation approach was employed to model key multiphase flow parameters. The analysis focused on gas distribution patterns, bubble size dispersion, and velocity profiles within the cleaning tank. Results reveal that the bubble tube geometry significantly influences multiphase flow behavior. Among the examined designs, the U-shaped elbow tube, featuring multiple bends, enables a broader spatial layout and a larger effective surface area within the tank. This configuration achieves improved gas retention, more uniform bubble size distribution, and enhanced flow homogeneity. Furthermore, the study evaluated the effects of process parameters, including gas flow rate, aperture diameter, and aperture spacing, based on the U-shaped elbow tube design. The findings indicate that both gas flow rate and aperture diameter are positively correlated with gas dispersion and bubble size, but inversely related to flow uniformity. The optimal operating conditions determined were a gas flow rate of 9 L, an aperture diameter of 1 mm, and an aperture spacing of 46 mm. Overall, this research provides valuable insights into the structural optimization of porous bubble tubes and the evaluation of nitrogen bubbling processes, contributing to improved wafer cleaning efficiency.