Thermodynamics-based sealing method for anodized aluminum used in semiconductor processing apparatuses

• The principle was proposed for designing a method to seal anodized aluminum used in semiconductor processing apparatuses. • Thermodynamic calculations were used to reveal trends in the metal ion deposition, the holding temperature, and time. • The ideal candidate for metal ion dipping was Cr 3+ , the steam sealing temperature was set as 150 °C, the holding time of steam sealing was chosen as 18 h. • Anodized aluminum dipped in Cr 3+ ion solution and steam-sealed for 18 h exhibited the highest corrosion resistance. A principle was proposed for designing a method to seal anodized aluminum used in semiconductor processing apparatuses. Thermodynamic calculations and Fick's second law were used to reveal trends in the metal ion deposition, deposition product stability, vapor pressures of halides for selected metal ions, the holding temperature, and time. Interactions between ion concentrations and the sealing temperature were also revealed. According to the design principles, anodized aluminum dipped in 1 mM Cr 3+ ion solution and steam-sealed for 18 h exhibited the highest corrosion resistance when exposed to 5 wt.% HCl solution and HCl gas, verifying the designed results.