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Optimized design of block copolymers with covarying properties for nanolithography

Nature Materials volume 21, pages 1426–1433 (2022)Cite this article

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Abstract

The ability to impart multiple covarying properties into a single material represents a grand challenge in manufacturing. In the design of block copolymers (BCPs) for directed self-assembly and nanolithography, materials often balance orthogonal properties to meet constraints related to processing, structure and defectivity. Although iterative synthesis strategies deliver BCPs with attractive properties, identifying materials with all the required attributes has been difficult. Here we report a high-throughput synthesis and characterization platform for the discovery and optimization of BCPs with A-block-(B-random-C) architectures for lithographic patterning in semiconductor manufacturing. Starting from a parent BCP and using thiol–epoxy ‘click’ chemistry, we synthesize a library of BCPs that cover a large and complex parameter space. This allows us to readily identify feature-size-dependent BCP chemistries for 8–20-nm-pitch patterns. These blocks have similar surface energies for directed self-assembly, and control over the segregation strength to optimize the structure (favoured at higher segregation strengths) and defectivity (favoured at lower segregation strengths).

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Fig. 1: Design principle for creating a series of BCPs with tunable χN and Δγ = 0 using an A-b-(B-r-C) polymer architecture.
Fig. 2: Determination of χ and γ of S-b-G(TFET-r-2MP) with varying φ.
Fig. 3: Thermodynamics, surface energies and self-assembled morphologies of modified S-b-G BCPs.
Fig. 4: Two additional advantages of the S-b-G BCP platform: enhanced etch contrast and self-brushing.
Fig. 5: Tailoring the BCP for specific industry applications.

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Data availability

The data supporting the findings of this study are available within the Article, its Supplementary Information files and from the corresponding authors upon reasonable request. Source data are provided with this paper.

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Acknowledgements

This research was supported by the US Department of Commerce, National Institute of Standards and Technology, as part of the Center for Hierarchical Materials Design (CHiMaD). Part of this work was carried out at the Soft Matter Characterization Facility of the University of Chicago. Surface energy measurements were carried out in KRÜSS Surface Science Laboratory in the University of Chicago. This facility is a joint collaborative venture with KRÜSS. We acknowledge the MRSEC Shared User Facilities at the University of Chicago (NSF DMR-1420709). This work made use of the Pritzker Nanofabrication Facility of the Pritzker School of Molecular Engineering at the University of Chicago, which receives support from Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF ECCS-1542205), a node of the National Science Foundation’s National Nanotechnology Coordinated Infrastructure. Work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under contract no. DE-AC02-05CH11231. N.Z. acknowledges Jiangsu Overseas Visiting Scholar Program for University Prominent Young & Middle-Aged Teachers and Presidents.

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Author notes

  1. These authors contributed equally: Hongbo Feng, Moshe Dolejsi, Ning Zhu.

Authors and Affiliations

  1. Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA

    Hongbo Feng, Moshe Dolejsi, Soonmin Yim, Whitney Loo, Peiyuan Ma, Chun Zhou, Gordon S. W. Craig, Wen Chen, Juan J. de Pablo, Stuart J. Rowan & Paul F. Nealey

  2. College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China

    Ning Zhu

  3. Western Digital Corporation, San Jose, CA, USA

    Lei Wan

  4. The Molecular Foundry, Lawrence Berkeley National Lab, Berkeley, CA, USA

    Ricardo Ruiz

  5. Department of Chemistry, University of Chicago, Chicago, IL, USA

    Stuart J. Rowan

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Contributions

H.F., M.D. and N.Z. designed and carried out the experiments and analysed the data, with supervision from S.J.R. and P.F.N. S.Y. performed the etch selectivity study and DSA work. P.M. and C.Z. performed a portion of the polymer synthesis and island–hole test. W.L. and W.C. performed the DSA and SEM imaging. H.F., M.D., N.Z., S.Y., G.S.W.C., J.J.d.P., S.J.R. and P.F.N. wrote the manuscript.

Corresponding authors

Correspondence to Stuart J. Rowan or Paul F. Nealey.

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Feng, H., Dolejsi, M., Zhu, N. et al. Optimized design of block copolymers with covarying properties for nanolithography. Nat. Mater. 21, 1426–1433 (2022). https://doi.org/10.1038/s41563-022-01392-1

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