Nanostructure fabrication in silicon using cesium to pattern a self-assembled monolayer

This letter describes the formation of nanometer-scale features in a silicon substrate using a self-assembled monolayer (SAM) of octylsiloxane on silicon dioxide as a resist sensitive to a patterned beam of neutral cesium atoms. The mask that patterned the atomic beam was a silicon nitride membrane perforated with nm and μm scale holes, in contact with the substrate surface. In a two-step wet-chemical etching process, the pattern formed in the SAM was transferred first into the SiO2 layer and then into an underlying silicon substrate. This process demonstrated the formation of silicon features with diameter ∼60 nm.