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Regular arrays of highly ordered ferroelectric polymer nanostructures for non-volatile low-voltage memories

Nature Materials volume 8, pages 62–67 (2009)Cite this article

Abstract

Ferroelectric nanostructures are attracting tremendous interest because they offer a promising route to novel integrated electronic devices such as non-volatile memories and probe-based mass data storage. Here, we demonstrate that high-density arrays of nanostructures of a ferroelectric polymer can be easily fabricated by a simple nano-embossing protocol, with integration densities larger than 33 Gbits inch−2. The orientation of the polarization axis, about which the dipole moment rotates, is simultaneously aligned in plane over the whole patterned region. Internal structural defects are significantly eliminated in the nanostructures. The improved crystal orientation and quality enable well-defined uniform switching behaviour from cell to cell. Each nanocell shows a narrow and almost ideal square-shaped hysteresis curve, with low energy losses and a coercive field of ∼10 MV m−1, well below previously reported bulk values. These results pave the way to the fabrication of soft plastic memories compatible with all-organic electronics and low-power information technology.

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Figure 1: Fabrication by nano-embossing of high-density arrays of crystalline nanostructures of a ferroelectric polymer.
Figure 2: Microstructure of nano-imprinted P(VDF-TrFE).
Figure 3: Ferroelectric properties of the P(VDF-TrFE) nanostructures.

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Acknowledgements

We are grateful to P. Ghosez for discussions on ferroelectric materials. Financial support was provided by the Fondation Louvain (Fonds de Recherche Solvay), the Communauté Française de Belgique (ARC 06-11/339), the Wallonia Region (Nanotic excellence program) and the Belgian Federal Science Policy (IAP-PAI P6/27). B.N. is a Senior Research Associate of the F.R.S.-FNRS.

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Authors and Affiliations

  1. Unité de Physique et de Chimie des Hauts Polymères (POLY), Université catholique de Louvain, Place Croix du Sud 1, B-1348 Louvain-la-Neuve, Belgium

    Zhijun Hu, Bernard Nysten & Alain M. Jonas

  2. Research Center in Micro- and Nanoscopic Materials and Electronic Devices, CeRMiN, Université catholique de Louvain, Place Croix du Sud 1, B-1348 Louvain-la-Neuve, Belgium

    Zhijun Hu, Bernard Nysten & Alain M. Jonas

  3. NT-MDT Europe B. V., De Pinckart 54, 5674 CC, Nuenen, The Netherlands

    Mingwen Tian

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  1. Zhijun Hu
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Contributions

Z.H. designed and carried out the experiments, participated in the data analysis and wrote the paper. M.T. provided support for the PFM measurements. B.N. provided support for the interpretation of AFM experiments. A.M.J. planned the project, contributed to the experiment design and data analysis, and wrote the paper.

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Correspondence to Alain M. Jonas.

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Hu, Z., Tian, M., Nysten, B. et al. Regular arrays of highly ordered ferroelectric polymer nanostructures for non-volatile low-voltage memories. Nature Mater 8, 62–67 (2009). https://doi.org/10.1038/nmat2339

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