A method for decontaminating residual halogen species in a processed metal-containing layer without breaking vacuum includes processing a metal-containing layer (such as a metal oxide layer) using a halogen-containing process gas to form a processed metal-containing layer that includes residual halogen species, and chemically modifying the residual halogen species to form modified residual species using a reactive gas to decontaminate the residual halogen species. Decontamination may include neutralization and/or removal of the residual halogen species. The metal-containing layer may be an organometal oxide photoresist and processing with the halogen-containing process gas may form a patterned photoresist layer contaminated with the residual halogen species. The modified residual species may be further treated using dinitrogen plasma (pure or with additional gases) and/or additional reactive gases, both of which may be combined with maintaining and higher or lower temperature during the treatment.

A catalyst for removing nitrous oxide and a method of removing nitrous oxide are provided. The catalyst includes a metal oxide powder and an iron-copper compound. The iron-copper compound is attached to the surface of the metal oxide powder, where the metal oxide powder includes zinc oxide, magnesium oxide, aluminum oxide, or a combination thereof. A molar ratio of iron in the iron-copper compound to the metal in the metal oxide powder is 1:1.3-4.0.