title: Aligned silicon nanofins via the directed self-assembly of PS-b-P4VP block copolymer and metal oxide enhanced pattern transfer.
abstract: 'Directing' block copolymer (BCP) patterns is a possible option for future semiconductor device patterning, but pattern transfer of BCP masks is somewhat hindered by the inherently low etch contrast between blocks. Here, we demonstrate a 'fab' friendly methodology for forming well-registered and aligned silicon (Si) nanofins following pattern transfer of robust metal oxide nanowire masks through the directed self-assembly (DSA) of BCPs. A cylindrical forming poly(styrene)-block-poly(4-vinyl-pyridine) (PS-b-P4VP) BCP was employed producing 'fingerprint' line patterns over macroscopic areas following solvent vapor annealing treatment. The directed assembly of PS-b-P4VP line patterns was enabled by electron-beam lithographically defined hydrogen silsequioxane (HSQ) gratings. We developed metal oxide nanowire features using PS-b-P4VP structures which facilitated high quality pattern transfer to the underlying Si substrate. This work highlights the precision at which long range ordered ∼10 nm Si nanofin features with 32 nm pitch can be defined using a cylindrical BCP system for nanolithography application. The results show promise for future nanocircuitry fabrication to access sub-16 nm critical dimensions using cylindrical systems as surface interfaces are easier to tailor than lamellar systems. Additionally, the work helps to demonstrate the extension of these methods to a 'high χ' BCP beyond the size limitations of the more well-studied PS-b-poly(methyl methylacrylate) (PS-b-PMMA) system.
authors: Materials Research Group, Department of Chemistry and Tyndall National Institute, University College Cork, Cork, Ireland. cian.a.cummins@gmail.com m.morris@ucc.ie.
authors: Cian
authors: C
authors: Cummins
authors: Anushka
authors: A
authors: Gangnaik
authors: Roisin A
authors: RA
authors: Kelly
authors: Dipu
authors: D
authors: Borah
authors: John
authors: J
authors: O'Connell
authors: Nikolay
authors: N
authors: Petkov
authors: Yordan M
authors: YM
authors: Georgiev
authors: Justin D
authors: JD
authors: Holmes
authors: Michael A
authors: MA
authors: Morris