title: Patterning at the 10 nanometer length scale using a strongly segregating block copolymer thin film and vapor phase infiltration of inorganic precursors.
abstract: In this work, we demonstrate the use of self-assembled thin films of the cylinder-forming block copolymer poly(4-tert-butylstyrene-block-2-vinylpyridine) to pattern high density features at the 10 nm length scale. This material's large interaction parameter facilitates pattern formation in single-digit nanometer dimensions. This block copolymer's accessible order-disorder transition temperature allows thermal annealing to drive the assembly of ordered 2-vinylpyridine cylinders that can be selectively complexed with the organometallic precursor trimethylaluminum. This unique chemistry converts organic 2-vinylpyridine cylinders into alumina nanowires with diameters ranging from 8 to 11 nm, depending on the copolymer molecular weight. Graphoepitaxy of this block copolymer aligns and registers sub-12 nm diameter nanowires to larger-scale rectangular, curved, and circular features patterned by optical lithography. The alumina nanowires function as a robust hard mask to withstand the conditions required for patterning the underlying silicon by plasma etching. We conclude with a discussion of some of the challenges that arise with using block copolymers for patterning at sub-10 nm feature sizes.
authors.affiliation: Department of Materials Science and Engineering, University of Wisconsin-Madison, Wisconsin 53706, USA. pgopalan@cae.wisc.edu.
authors.forename: Jonathan W
authors.initials: JW
authors.lastname: Choi
authors.affiliation: Department of Materials Science and Engineering, University of Wisconsin-Madison, Wisconsin 53706, USA. pgopalan@cae.wisc.edu.
authors.forename: Zhaodong
authors.initials: Z
authors.lastname: Li
authors.affiliation: Center for Functional Nanomaterials, Brookhaven National Laboratory, New York 11973, USA.
authors.forename: Charles T
authors.initials: CT
authors.lastname: Black
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison, Wisconsin 53706, USA.
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Sweat
authors.affiliation: Department of Materials Science and Engineering, University of Wisconsin-Madison, Wisconsin 53706, USA. pgopalan@cae.wisc.edu.
authors.forename: Xudong
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Materials Science and Engineering, University of Wisconsin-Madison, Wisconsin 53706, USA. pgopalan@cae.wisc.edu.
authors.forename: Padma
authors.initials: P
authors.lastname: Gopalan