Polylactide - Poly(dimethylsiloxane) - Polylactide Triblock Copolymers as Multifunctional Materials for Nanolithographic Applications

Highly immiscible block copolymers are attractive materials for applications in nanolithography due to their ability to self-assemble on length scales that are difficult to access by conventional lithography. The incorporation of inorganic domains into such block copolymers provides etch contrast that can potentially reduce processing times and costs in nanolithographic applications. We explored thin films of polylactide-poly(dimethylsiloxane)-polylactide (PLA-PDMS-PLA) triblock copolymers as multifunctional nanolithographic templates. We demonstrate the formation of well-ordered arrays of hexagonally packed PDMS cylinders oriented normal to the substrate, the orthogonal etchability of these cylinders and the PLA matrix, and the formation of etch-resistant domains that can be used as pattern transfer masks.