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Internal structure visualization and lithographic use of periodic toroidal holes in liquid crystals


The formation of a large-area ordered structure by organic molecular soft building blocks is one of the most exciting interdisciplinary research areas in current materials science1 and nanotechnology2,3,4. So far, several distinct organic building blocks—including colloids, block copolymers and surfactants—have been examined as potential materials for the creation of lithographic templates1,5,6. Here, we report that perfect ordered arrays of toric focal conic domains (TFCDs) covering large areas can be formed by semi-fluorinated smectic liquid crystals. Combined with controlled geometry, that is, a microchannel, our smectic liquid-crystal system exhibits a high density of TFCDs that are arranged with remarkably high regularity. Direct visualization of the internal structure of the TFCDs clearly verified that the smectic layers were aligned normal to the side walls and parallel to the top surface, and merge with the circular profile on the bottom wall surface. Moreover, we demonstrate a new concept: smectic liquid-crystal lithography. Grown in microchannels from a mixture of liquid-crystal molecules and fluorescent particles, TFCDs of the smectic liquid crystals acted as a template, trapping particles in an ordered array. Our findings pose new theoretical challenges and potentially enable lithographic applications based on smectic liquid-crystalline materials.

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Figure 1: Liquid-crystal material and model of confined geometry.
Figure 2: The dense population of TFCDs in the microchannels.
Figure 3: Direct visualization of the internal structure of the TFCDs.
Figure 4: Trapped fluorescent silica particles in TFCDs.

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  1. Cao, G. Nanostructures and Nanomaterials: Synthesis, Properties & Applications (Imperial College Press, New York, 2004).

    Book  Google Scholar 

  2. Whitesides, G. M. & Grzybowski, B. Self-assembly at all scales. Science 295, 2418–2421 (2002).

    Article  CAS  Google Scholar 

  3. Stenzel, M. H., Barner-Kowollik, C. & Davis, J. P. Formation of honeycomb-structured, porous films via breath figures with different polymer architectures. J. Polym. Sci. A 44, 2363–2375 (2006).

    Article  CAS  Google Scholar 

  4. Barth, J. V., Costantini, G. & Kern, K. Engineering atomic and molecular nanostructures at surfaces. Nature 437, 671–679 (2005).

    Article  CAS  Google Scholar 

  5. Jones, R. A. Soft Condensed Matter (Oxford Univ. Press, New York, 2002).

    Book  Google Scholar 

  6. Cheng, J. Y., Mayes, A. M. & Ross, C. A. Nanostructure engineering by templated self-assembly of block copolymers. Nature Mater. 3, 823–828 (2004).

    Article  CAS  Google Scholar 

  7. Kleman, M. & Lavrentovich, O. D. Soft Matter Physics (Springer, New York, 2003).

    Google Scholar 

  8. Li, Z. & Lavrentovich, O. D. Surface anchoring and growth pattern of the field-driven first-order transition in a smectic-A liquid crystal. Phys. Rev. Lett. 73, 280–284 (1994).

    Article  CAS  Google Scholar 

  9. Choi, M. C. et al. Ordered patterns of liquid crystal toroidal defects by microchannel confinement. Proc. Natl Acad. Sci. USA 101, 17340–17344 (2004).

    Article  CAS  Google Scholar 

  10. Dierking, I. Textures of Liquid Crystals (Wiley-VCH, Weinheim, 2003).

    Book  Google Scholar 

  11. Johansson, G., Percec, V., Ungar, G. & Zhou, J. P. Fluorophobic effect in the self-assembly of polymers and model compounds containing tapered groups into supramolecular columns. Macrocmolecules 29, 646–660 (1996).

    Article  CAS  Google Scholar 

  12. Johansson, G., Percec, V., Ungar, G. & Smith, K. Fluorophobic effect generates a systematic approach to the synthesis of the simplest class of rodlike liquid crystals containing a single benzene unit. Chem. Mater. 9, 164–175 (1997).

    Article  CAS  Google Scholar 

  13. Gray, G. W. & Goodby, J. W. Some effects of small changes in molecular framework on the incidence of smectic C and other smectic liquid crystal phases in esters. Mol. Cryst. Liq. Cryst. 37, 157 (1976).

    Article  CAS  Google Scholar 

  14. de Gennes, P.-G. & Prost, J. The Physics of Liquid Crystals (Clarendon, Oxford, 1993).

    Google Scholar 

  15. Lee, E. H. et al. Alignment of perfluorinated supramolecular columns on the surfaces of various self-assembled monolayers. Macromolecules 38, 5152–5157 (2005).

    Article  CAS  Google Scholar 

  16. Yoon, D. K. et al. Large-area, highly aligned cylindrical semi-fluorinated supramolecular dendrimers using magnetic fields. Adv. Mater. 18, 509–513 (2006).

    Article  CAS  Google Scholar 

  17. Percec, V. et al. Self-organization of supramolecular helical dendrimers into complex electronic materials. Nature 419, 384–387 (2002).

    Article  CAS  Google Scholar 

  18. Tomalia, D. A. Supramolecular chemistry—fluorine makes a difference. Nature Mater. 2, 711–712 (2003).

    Article  CAS  Google Scholar 

  19. Percec, V. et al. Self-assembly of amphiphilic dendritic dipeptides into helical pores. Nature 430, 764–768 (2004).

    Article  CAS  Google Scholar 

  20. Jung, H.-T. et al. Elastic properties of hexagonal columnar mesophase self-organized from amphiphilic supramolecular columns. Appl. Phys. Lett. 80, 395–397 (2002).

    Article  CAS  Google Scholar 

  21. Jung, H.-T., Lee, S.-Y., Kaler, E. W., Coldren, B. & Zasadzinski, J. A. Gaussian curvature and the equilibrium among bilayer cylinders, spheres, and discs. Proc. Natl Acad. Sci. USA 99, 15318–15322 (2002).

    Article  CAS  Google Scholar 

  22. Pivovarova, N. S., Boldescul, I. E., Lavrentovich, O. D., Shelyazhenko, S. V. & Fialkov, Y. A. Mesomorphism of MBBA fluorinated derivatives. Kristallografiya 33, 1460–1463 (1988).

    CAS  Google Scholar 

  23. Lavrentovich, O. D. Hierarchy of defect structures in space filling by flexible smectic-A layers. Sov. Phys. JETP 64, 984 (1986).

    Google Scholar 

  24. Fournier, J. B., Dozov, I. & Durand, G. Surface frustration and texture instability in smectic-A liquid crystals. Phys. Rev. A 41, 2252–2255 (1990).

    Article  CAS  Google Scholar 

  25. Smalyukh, I. I. et al. Ordered droplet structures at the liquid crystal surface and elastic-capillary colloidal interactions. Phys. Rev. Lett. 93, 117801–117804 (2004).

    Article  CAS  Google Scholar 

  26. Poulin, P., Stark, H., Lubensky, T. C. & Weitz, D. A. Novel colloidal interactions in anisotropic fluids. Science 275, 1770–1773 (1997).

    Article  CAS  Google Scholar 

  27. Voloschenko, D., Pishnyak, O. P., Shiyanovskii, S. V. & Lavrentovich, O. D. Effect of director distortions on morphologies of phase separation in liquid crystals. Phys. Rev. E 65, 060701–060704 (2002).

    Article  CAS  Google Scholar 

  28. Blanc, C. & Kleman, M. The confinement of smectics with a strong anchoring. Eur. Phys. J. E 4, 241–251 (2001).

    Article  CAS  Google Scholar 

  29. Madou, M. J. Fundamentals of Microfabrication (CRC Press, LLC, 2002).

    Book  Google Scholar 

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This work was supported by the National Research Laboratory Program of the Korea Science and Engineering Foundation (KOSEF), the Basic Research Program (R01-2005-000-10456-0), the KRF (2005-908-D00018), the Korea Health 21 R&D Project of MOHW and the CUPS-ERC program. X-ray experiments were carried out at PLS were supported in part by MOST and POSCO. M.C.C. received partial support from the Korean Research Foundation Grant KRF-2005-2214-C00202. O.D.L. acknowledges the support of a NSF DMR 0504516 grant.

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Correspondence to Hee-Tae Jung.

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Yoon, D., Choi, M., Kim, Y. et al. Internal structure visualization and lithographic use of periodic toroidal holes in liquid crystals. Nature Mater 6, 866–870 (2007).

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