Aligned silicon nanofins via the directed self-assembly of PS-b-P4VP block copolymer and metal oxide enhanced pattern transfer

Thumbnail Image
CC_AlignedPV2015.pdf(4.03 MB)
Published Version
Cummins, Cian
Gangnaik, Anushka S.
Kelly, Róisín A.
Borah, Dipu
O'Connell, John
Petkov, Nikolay
Georgiev, Yordan M.
Holmes, Justin D.
Morris, Michael A.
Journal Title
Journal ISSN
Volume Title
The Royal Society of Chemistry
Published Version
Research Projects
Organizational Units
Journal Issue
'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 [similar]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 [small chi]' BCP beyond the size limitations of the more well-studied PS-b-poly(methyl methylacrylate) (PS-b-PMMA) system.
Block copolymers , Copolymers , Metallic compounds , Nanowires , Self assembly , Semiconductor devices , Styrene , Critical dimension , Directed assembly , Directed self-assembly , Hydrogen silsequioxane , Metal oxide nanowires , Pattern transfers , Solvent-vapor annealing , Surface interfaces , Silicon
CUMMINS, C., GANGNAIK, A., KELLY, R. A., BORAH, D., O'CONNELL, J., PETKOV, N., GEORGIEV, Y. M., HOLMES, J. D. & MORRIS, M. A. 2015. Aligned silicon nanofins via the directed self-assembly of PS-b-P4VP block copolymer and metal oxide enhanced pattern transfer. Nanoscale, 7, 6712-6721.