Metal Contamination Behavior on Silicon Dioxide Surface Rinsed With Deionized Water Containing Ultra-Trace Metal During Single-Wafer Cleaning

Metal contamination control in semiconductor manufacturing processes is important because it affects device reliability and yield. The metal contamination control value in deionized water (DIW) is required at the pg/L level for advanced device manufacturing. However, previous studies on metallic contamination proved insufficient owing to their utilization of highly concentrated solutions at a $\mu $ g/L level with batch rinsing processes. In this study, we investigated the contamination behavior of metal impurities at the pg/L level in DIW on the silicon dioxide (SiO2) surface during a single-wafer cleaning process. We found that Al, Ti, Fe, Zn, and Ga were highly adsorbed for the $SiO_{2}$ surface, and these surface concentrations were positively correlated with the concentration in DIW and the rinse time. Whereas the adsorption behavior of these metals affected by rinse fluid parameters such as the rotation speed and the flow rate. The adsorption probability increased owing to thinning of the liquid-firm thickness and increasing radial velocity. Furthermore, the metal adsorption ratio was decreased with thinning boundary-layer thickness. Herein, we provide new insights into the pertinence of reducing metal concentrations in DIW and optimizing fluid parameters during a single-wafer cleaning to prevent metal contamination for advanced the semiconductor manufacturing process.