Using neutral metastable argon atoms and contamination lithography to form nanostructures in silicon, silicon dioxide, and gold

This letter describes the fabrication of ∼80 nm structures in silicon, silicon dioxide, and gold substrates by exposing the substrates to a beam of metastable argon atoms in the presence of dilute vapors of trimethylpentaphenyltrisiloxane, the dominant constituent of diffusion pump oil used in these experiments. The atoms release their internal energy upon contacting the siloxanes physisorbed on the surface of the substrate, and this release causes the formation of a carbon-based resist. The atomic beam was patterned by a silicon nitride membrane, and the pattern formed in the resist material was transferred to the substrates by chemical etching. Simultaneous exposure of large areas (44 cm2) was also demonstrated.