title: Controlled solvent vapor annealing of a high χ block copolymer thin film.
abstract: Molecular self-assembling block copolymers (BCPs) have shown promise as a next generation bottom-up lithography technology. However, a critical step in advancing this approach is the elimination of polymer dewetting due to bulk solvent nucleation and thermodynamically driven film rupture that can occur during the solvent vapor annealing process. We report on the pattern formation via phase segregation of spin coated diblock copolymer films through the investigation of annealing parameters in the limit of high solvent vapor saturation conditions that results in wafer-scale patterning without observing polymer dewetting defects. Specifically, the work addresses polymer dewetting in diblock copolymer nanodot templates through the use of a "neutral" functionalization layer and the development of a custom-built solvent vapor annealing chamber to precisely control saturation conditions. Furthermore, the long anneal times (4 h) using a standard static solvent vapor annealing procedure were reduced to ∼15-30 minutes with our dynamic solvent vapor annealing system for the high χ, cylindrical forming poly(styrene)-block-poly(4-vinyl-pyridine) [PS-b-P4VP] diblock copolymer system. We discuss the kinetic mechanism governing the phase segregation process that highlights the small processing window bounded by long phase segregation timescales (≳1 min) on one side and the initiation of polymer film dewetting on the other. These results demonstrate a key step towards realizing a high fidelity, low cost BCP patterning technique for large-scale "bottom-up" feature definition at nanometer length scales.
authors.affiliation: Thermal Management Research Group, Efficient Energy Transfer (ηET) Dept., Bell Labs Ireland, Nokia, Blanchardstown Business & Technology Park, Snugborough Rd., Dublin 15, Ireland. ross.lundy2@gmail.com ryan.enright@nokia.com and Stokes Laboratories, University of Limerick, Co., Limerick, Ireland.
authors.forename: Ross
authors.identifier: http://orcid.org/0000-0002-1329-8614
authors.initials: R
authors.lastname: Lundy
authors.affiliation: National Centre for Plasma Science and Technology, Dublin City University, Glasnevin, Dublin 9, Ireland.
authors.forename: Shauna P
authors.initials: SP
authors.lastname: Flynn
authors.affiliation: AMBER@CRANN, Trinity College Dublin, Dublin, Ireland.
authors.forename: Cian
authors.initials: C
authors.lastname: Cummins
authors.affiliation: National Centre for Plasma Science and Technology, Dublin City University, Glasnevin, Dublin 9, Ireland.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Kelleher
authors.affiliation: Stokes Laboratories, University of Limerick, Co., Limerick, Ireland.
authors.forename: Maurice N
authors.initials: MN
authors.lastname: Collins
authors.affiliation: Stokes Laboratories, University of Limerick, Co., Limerick, Ireland.
authors.forename: Eric
authors.initials: E
authors.lastname: Dalton
authors.affiliation: National Centre for Plasma Science and Technology, Dublin City University, Glasnevin, Dublin 9, Ireland.
authors.forename: Stephen
authors.initials: S
authors.lastname: Daniels
authors.affiliation: AMBER@CRANN, Trinity College Dublin, Dublin, Ireland.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Morris
authors.affiliation: Thermal Management Research Group, Efficient Energy Transfer (ηET) Dept., Bell Labs Ireland, Nokia, Blanchardstown Business & Technology Park, Snugborough Rd., Dublin 15, Ireland. ross.lundy2@gmail.com ryan.enright@nokia.com.
authors.forename: Ryan
authors.initials: R
authors.lastname: Enright