Evaluation of Corrosion Characteristics of 316L Stainless Steel for Semiconductor Processes Exposed to Dry and Wet Chlorine Gas Environments

This study investigated corrosion behavior of 316L stainless steel exposed to chlorine gas (Cl(2)gas) in dry and wet environments at room temperature. Experiments were conducted over 14 days using both electropolished and non-electropolished specimens to evaluate effects of surface treatment and environmental conditions on corrosion. The extent of corrosion was evaluated by measuring weight change and corrosion rate (mm/ year). Surface morphology, cross-section almorphology, and corrosion layer were analyzed using SEM/EDS mapping. The non-electropolished specimens formed a corrosion layer more than 7 mu m thick, composed of Fe, Cr, Cl, and O. Electropolished specimens maintained a pristine surface with no formation of a corrosion layer. Weight measurements indicated that non-electropolished specimens experienced a weight change of 5.44 mg/cm(2) in wet conditions, which was over four times higher than that observed in dry conditions. In contrast, electropolished specimens demonstrated exceptional corrosion resistance due to a stable Cr oxide layer, showing a minimal weight change of less than 0.01 mg/cm(2) regardless of moisture presence.