@misc{hu_continuous_equilibrated_2013, 
author={Hu, H., Rangou, S., Kim, M., Gopalan, P., Filiz, V., Avgeropoulos, A., Osuji, C.O.},
title={Continuous Equilibrated Growth of Ordered Block Copolymer Thin Films by Electrospray Deposition},
year={2013},
howpublished = {journal article},
doi = {https://doi.org/10.1021/nn400279a},
abstract = {Deposition of block copolymer thin films is most often accomplished in a serial process where material is spin coated onto a substrate and subsequently annealed, either thermally or by solvent vapor, to produce a well-ordered morphology. Here we show that under appropriate conditions, well-ordered block copolymer films may be continuously grown under substrate equilibrated conditions by slow deposition of discrete subattoliter quantities of material using electrospray. We conduct time-resolved observations and investigate the effects of process parameters that underpin film morphology including solvent selectivity, substrate temperature, block-substrate selectivity, and flow rate of the feed solution. For a PEO cylinder-forming poly(styrene-b-ethylene oxide) block copolymer, we uncover a wide temperature window from 90 to 150 °C and an ideal flow rate of 2 μL/min for ordered film deposition from dilute acetone solutions. PEO cylinders aligned with their long axes perpendicular to the film–air interface at optimal spray conditions. Using poly(styrene-b-methyl methacrylate) deposited onto neutrally selective surfaces, we show that the substrate-equilibrated process results in vertically oriented microdomains throughout the film, indicating a preservation of the initial substrate-dictated morphology during the film deposition. Electrospray offers a new and potentially exciting route for controlled, continuous growth of block copolymer thin films and manipulation of their microstructure.},
note = {Online available at: \url{https://doi.org/10.1021/nn400279a} (DOI). Hu, H.; Rangou, S.; Kim, M.; Gopalan, P.; Filiz, V.; Avgeropoulos, A.; Osuji, C.: Continuous Equilibrated Growth of Ordered Block Copolymer Thin Films by Electrospray Deposition. ACS Nano. 2013. vol. 7, no. 4, 2960-2970. DOI: 10.1021/nn400279a}}