Abstract: A resist is formed by sorption of an inorganic-containing gas into an organic material. The development of the resist occurs by exposure to a plasma (e.g., oxygen reactive ion etching) that forms a protective compound (e.g., a metal oxide) selectively in the resist. The selected regions can be defined by patterning radiation of various types, including visible, ultraviolet, electron beam, and ion beam. In an alternate embodiment, the selected regions are defined by an overlying resist, with the gas sorption protecting the underlying layer in a bilevel resist. The protective compound can protect the organic resist layer during etching of an underlying inorganic layer, such as metal, silicide, oxide, nitride, etc.