Ultrafine Particle Removal in the Wafer Cleaning Process Using an Aqueous Solution with a High Concentration of Dissolved O<sub>3</sub> and HF

Sulfuric Peroxide Mixture (SPM, H 2 SO 4 + H 2 O 2 ) has been widely used in semiconductor manufacturing processes due to its high reactivity and attractive price. However, SPM releases SO 4 2 - ions that can be high impact on the environmental contaminations. Therefore, the SPM process requires a high cost wastewater treatment. So, the development of alternative chemicals has been becoming an important task in the semiconductor manufacturing process. In this paper, we evaluated the feasibility of replacing SPM with dissolved ozone water (DIO 3 ) in the wafer cleaning process, and confirmed that the Particle removal efficiency (PRE) was improved around 68% by mixing with diluted hydrofluoric acid (DHF). And, the PRE was also increased when the concentration of ozone in dissolved ozone water increased. Additionally the PRE was improved up to 98% by combining physical cleaning after O 3 process.