Templated self-assembly of Si-containing block copolymers for nanoscale device fabrication

Block copolymers have been proposed for self-assembled nanolithography because they can spontaneously form well-ordered nanoscale periodic patterns of lines or dots in a rapid, low-cost process. By templating the selfassembly, patterns of increasing complexity can be generated, for example arrays of lines with bends or junctions. This offers the possibility of using a sparse template, written by electron-beam lithography or other means, to organize a dense array of nanoscale features. Pattern transfer is simplified if one block is etch resistant and one easily removable, and in this work we use a diblock copolymer or a triblock terpolymer with one Sicontaining block such as polydimethylsiloxane or polyferrocenylsilane, and one or two organic blocks such as polystyrene or polyisoprene. Removal of the organic block(s) with an oxygen plasma leaves a pattern of Sicontaining material which can be used as an etch mask for subsequent pattern transfer to make metallization lines or magnetic nanostructures with feature sizes below 10 nm and periodicity below 20 nm.