Masanori Ozaki

Graduate School of Engineering, Osaka University
Professor
A03
Research AreasElectronics materials and devices
Participating Group (2020-2021)

Development of printable soft-crystal electronic devices utilizing potential liquid-crystalline properties

Keywords
liquid crystal, organic semiconductor, polymorphic transformation, phthalocyanine, organic electronics
Co-Researcher
Co-Researcher: Akihiko Fujii(Graduate School of Engineering, Osaka University, Associate Professor)
Co-Researcher: Hiroyuki Yoshida (Graduate School of Engineering, Osaka University, Assistant Professor)

Research Outline

Liquid crystals having both liquid and crystal properties have already been successfully applied to optical devices and displays because they have orientational order of molecules and high external-field-responsiveness at the same time. The orientational order of the liquid crystal molecules is of the order of nanometer scale, which is sufficient for the its application to an optical device. However, in the application of electronic devices requiring an order of angstrom scale, the molecular order of liquid crystals is insufficient. Therefore, considering soft crystals as an intermediate state between liquid crystals and crystals, we aim to “crystallize” liquid crystal while ensuring the flexibility and mobility of the liquid crystal and create a soft crystal that combines precise orientational order of molecules in angstrom scale and molecular arrangement order of meter scale by self-organization. At the same time, we aim to create new optical and electronic devices based on the synergistic effects of the superior features of both by combining liquid crystals and soft crystals.

From Liquid Crystals to Soft Crystal
Single-Crystal Thin-Film Growth based on Polymorphic Transformation
Participating Group (2018-2019)

Development of Soft Crystals based on Liquid Crystal Science and Exploration of their Novel Functions

Keywords
liquid crystal, organic semiconductor, polymorphic transformation, phthalocyanine, organic electronics
Co-Researcher
Co-Researcher: Akihiko Fujii(Graduate School of Engineering, Osaka University, Associate Professor)
Co-Researcher: Hiroyuki Yoshida (Graduate School of Engineering, Osaka University, Lecturer)

Research Outline

Liquid crystals having both liquid and crystal properties have already been successfully applied to optical devices and displays because they have orientational order of molecules and high external-field-responsiveness at the same time. The orientational order of the liquid crystal molecules is of the order of nanometer scale, which is sufficient for the its application to an optical device. However, in the application of electronic devices requiring an order of angstrom scale, the molecular order of liquid crystals is insufficient. Therefore, considering soft crystals as an intermediate state between liquid crystals and crystals, we aim to “crystallize” liquid crystal while ensuring the flexibility and mobility of the liquid crystal and create a soft crystal that combines precise orientational order of molecules in angstrom scale and molecular arrangement order of meter scale by self-organization. At the same time, we aim to create new optical and electronic devices based on the synergistic effects of the superior features of both by combining liquid crystals and soft crystals.

From Liquid Crystals to Soft Crystal
Single-Crystal Thin-Film Growth based on Polymorphic Transformation

Publications

Academic papers/reviewed

A03-15

  1. "Blue Phase Liquid Crystals with Tailored Crystal Orientation for Photonic Applications" S.Y. Cho, *M. Ozaki, Symmetry, 13, 1584 (2021).
    DOI: 10.3390/sym13091584
  2. "Directed Self-assembly of Soft 3D Photonic Crystals for Holograms with Omnidirectional Circular-polarization Selectivity" S.Y. Cho, M. Takahashi, J. Fukuda, *H. Yoshida, M. Ozaki, Commun. Mater., 2, 39 (2021).
    DOI: 10.1038/s43246-021-00146-x
  3. "Direction-Selectable Ultra-Highly Oriented State of Donor-Acceptor Conjugated Polymer Induced by Slow Bar Coating Process", Y. Yabuuchi, Y. Minowa, H. Kajii, S. Nagano, *A. Fujii, M. Ozaki, Adv. Electron. Mater., 7, 2100313 (2021).
    DOI: 10.1002/aelm.202100313
  4. "Dynamics of Preaggregation and Film Formation of Donor-Acceptor p-Conjugated Polymers" Y. Yabuuchi, Y. Minowa, S. Nagamatsu, *A. Fujii, M. Ozaki, ACS Mater. Lett., 44, 205-211 (2022).
    DOI: 10.1021/acsmaterialslett.1c00734
  5. "Generation of a Focused Optical Vortex Beam using a Liquid Crystal Spiral Zone Plate" Y. Tsukamoto, H. Yoshida, *M. Ozaki, Optics Express, 30, 8667-8675 (2022).
    DOI: 10.1364/OE.451293
  6. "Generation of Coaxial Vortex Beams with Doubled Topological Charges using a Stacked Liquid Crystal Structure" Y. Tsukamoto, H. Yoshida, *M. Ozaki, Jpn. J. Appl. Phys., 60, 120906 (2021).
    DOI: 10.35848/1347-4065/ac3182/meta
  7. "In Situ Optical Characterization of Twinning in Liquid Crystalline Blue Phases" Y. Zhang, *H. Yoshida, S.Y. Cho, J. Fukuda, M. Ozaki, ACS Appl. Mater. Interfaces, 13, 36130–36137 (2021).
    DOI: 10.1021/acsami.1c06873
  8. "Orientation Control of 2D Perovskite in 2D/3D Heterostructure by Templated Growth on 3D Perovskite" G. Uzurano, N. Kuwahara, T. Saito, *A. Fujii, M. Ozaki, ACS Mater. Lett., 44, 378-384 (2022).
    DOI: 10.1021/acsmaterialslett.1c00709
  9. "Thickness Control and Photovoltaic Properties of CH3NH3PbI3 Bar-coated Thin Film" *A. Fujii, T. Oizumi, N. Kuwahara, G. Uzurano, T. Saito, Y. Yabuuchi, M. Ozaki, Jpn. J. Appl. Phys., 61, SB1032 (2022).
    DOI: 10.35848/1347-4065/ac211c
  10. "Tunable Polarization Volume Gratings Based on Blue Phase Liquid Crystals" S.Y. Cho, *H. Yoshida, M. Ozaki, Optics Express, 30, 1607-1614 (2022).
    DOI: 10.1364/OE.448301
  11. "Alkyl chain length dependence of carrier transport in solution-processed phthalocyanine thin films evaluated via MIS-CELIV method" W. J. Kim, Y. Nishikawa, Y. Nakayama, *A. Fujii, M. Ozaki, Jpn. J. Appl. Phys, 60, 031004 (2021).
    DOI: 10.1021/acs.jpcb.6b05397
  12. "Carrier transport study on triphenylamine-thienothiophene-based hole transport material by MIS-CELIV method" W.J. Kim, Y. Nishikawa, T.-T. Bui, F. Goubard, Q.-D. Dao, *A. Fujii, M. Ozaki, Jpn. J. Appl. Phys, 59, SGGG01 (2020).
    DOI: 10.7567/1347-4065/ab656b
  13. "Effects of alkyl-substituent length on photovoltaic performance of bulk heterojunction solar cells utilizing non-peripherally octaalkyltetrabenzotriazaporphyrins" Q.-D. Dao, *A. Fujii, H. Itani, Y. Shimizu, M. Ozaki, Jpn. J. Appl. Phys., 59, 101003 (2020).
    DOI: 10.35848/1347-4065/abb8b8
  14. "Effects of thermal expansion and degeneracy on ambipolar carrier mobility of nonperipherally hexyl-substituted phthalocyanine" M.Fujisaki, *A. Fujii, M. Yoneya, N. Tohnai, M. Ozaki, Appl. Phys. Express, 14, 041001 (2021).
    DOI: 10.35848/1882-0786/abe98c
  15. "Electrically Switchable Amplified Spontaneous Emission from Liquid Crystalline Phase of an AIEE-Active ESIPT Molecule" Y. Tsutsui, W. Zhang, S. Ghosh, T. Sakurai, H. Yoshida, M. Ozaki, T. Akutagawa, *S. Seki, Adv. Opt.Mater., 8, 1902158 (2020). (Inside Front Cover)
    DOI: 10.1002/adom.201902158
  16. "Emission Directio-Tunable Liquid Crystal Laser" S.Y. Cho, *H. Yoshida, M. Ozaki, Adv. Opt. Mater., 8, 2000375 (2019).
    DOI: 10.1002/adom.202000375
  17. "Extended conjugation of ESIPT-type dopants in nematic liquid crystalline phase for enhancing fluorescence efficiency and anisotropy" W. Zhang, S. Suzuki, T. Sakurai, H. Yoshida, Y. Tsutsui, M. Ozaki, S. Seki, Phys.Chem.Chem.Phys., 22, 28393 (2020).
    DOI: 10.1039/d0cp05415a
  18. "Molecular orientation and electrical properties in tert-butylated phthalocyanine thin film fabricated by uniaxial solution coating" G. Uzurano, Y. Yabuuchi, S. Nagano, H. Kajii, R. Ishiura, *A. Fujii, M. Yoneya, M. Ozaki, Electron. Comm. Jpn., 104, 113(2021).
    DOI: 10.1002/ecj.12297
  19. "Homo/hetero-epitaxial growth in tetrabenzotriazaporphyrin derivative thin film fabricated by contact freezing method with seed crystal", T. Kitagawa, M. Fujisaki, S. Nagano, N. Tohnai, A. Fujii, M. Ozaki, Appl. Phys. Exp., 2019, 12, 051011.
    DOI: 10.7567/1882-0786/ab15bb
  20. "Coating speed dependence of main chain orientation and aggregation of PBTTT-C16 in the bar-coated thin film" Y. Yabuuchi, G. Uzurano, R. Ishiura, M. Nakatani, S. Nagano, *A. Fujii, M. Ozaki, Jpn. J. Appl. Phys., 59, SDDA04-1- 7 (2020).
    DOI: 10.7567/1347-4065/ab51a8
  21. "Highly (100)-oriented CH3NH3PbI3 thin film fabricated by bar-coating method and its additive effect of ammonium chloride" M. Murata, M. Gi, R. Tsuji, M. Arita, *A. Fujii, M. Ozaki, Sol. Energy Mater. Sol. Cells, 208, 110409-1-7 (2020).
    DOI: 10.1016/j.solmat.2020.110409
  22. "Highly Miscible Hybrid Liquid Crystal Systems Containing Fluorescent Excited-State Intramolecular Proton Transfer Molecules" W. Zhang, S. Suzuki, S. Cho, G. Watanabe, H. Yoshida, *T. Sakurai, M. Aotani, Y. Tsutsui, M. Ozaki, S. Seki, Langmuir, 35, 14031-14041 (2019).
    DOI: 10.1021/acs.langmuir.9b02272
  23. "Optical properties of selective diffraction from Bragg-Berry cholesteric liquid crystal deflectors" *R. Ozaki, S. Hashimura, S. Yudate, K. Kadowaki, H. Yoshida, M. Ozaki, OSA Continuum., 2, 3354-3563 (2019).
    DOI: 10.1364/OSAC.2.003554
  24. "Solution processed uniaxially oriented thin film of tert-butyl-substituted phthalocyanine" G. Uzurano, Y. Yabuuchi, R. Ishiura, M. Yoneya, S. Nagano, *A. Fujii, M. Ozaki, Jpn. J. Appl. Phys., 59, SDDA05-1-5 (2020).
    DOI: 10.7567/1347-4065/ab5177
  25. "Stereoregularity effect on hole mobility in poly(N-vinylcarbazole) thin film evaluated by MIS-CELIV method" W. Kim, Y. Nishikawa, H. Watanabe, A. Kanazawa, S. Aoshima, *A. Fujii, M. Ozaki, Jpn. J. Appl. Phys., 59, SDDA01-1-5 (2020).
    DOI: 10.7567/1347-4065/ab554f
  26. "Study on energy level bending at heterojunction of solution-processed phthalocyanine thin film and n-Si by Kelvin probe force microscopy" R. Ishiura, *A. Fujii, M. Arita, K. Sudoh, M. Ozaki, Org. Electron., 78, 105599-1-5 (2020).
    DOI: 10.1016/j.orgel.2019.105599
  27. "Carrier transport and device applications of theorganic semiconductor based on liquid crystalline non-peripheral octaalkyl phthalocyanine" M. Ozaki, M. Yoneya, Y. Shimizu, A. Fujii, Liq. Cryst., 2018, 45, 2376-2389.
    DOI: 10.1080/02678292.2018.1530375
  28. "Uniaxial orientation of poly(3-hexylthiophene) thin films fabricated by the bar-coating method" Y. Yabuuchi, G. Uzurano, M. Nakatani, A. Fujii, M. Ozaki, Jap. J. Appl. Phys., 2019, 58, SBBG04-1-5.
    DOI: 10.7567/1347-4065/aafb5d

International conferences

A03-15

  1. "Analysis of Angular Dependence of Band Edge Wavelengths in Cholesteric Mirror and Bragg-Berry Cholesteric Deflector" R. Ozaki, S. Hashimura, K. Kadowaki, H. Yoshida, M. Ozaki, 19th Optics of Liquid Crystals (OLC 2021), (on line Sept. 26-Oct.1, 2021)
  2. "Fabrication of molecularly oriented organic semiconductor thin film utilizing its potential as a liquid crystal" M. Ozaki (Keynote), SPIE Organic Photonics + Electronics, Liquid Crystals XXV, (on line Aug. 1-5, 2021)
  3. "Generation of Focused Vortex Beam by Liquid Crystal Spiral Zone Plate with Homeotropic and Planer Patterned Alignment Layer" Y. Tsukamoto, H. Yoshida, M. Ozaki, 19th Optics of Liquid Crystals (OLC 2021), (on line Sept. 26-Oct.1, 2021)
  4. "Optical Characterization of the (211) Twin in Cholesteric Blue Phase I" H. Yoshida, Y. Zhang, S.Y. Cho, M. Ozaki (Invited), 19th Optics of Liquid Crystals (OLC 2021), (on line Sept. 26-Oct.1, 2021)
  5. "Polymerization Induced Fluorescence Enhancement of Aggregation-Induced Emission Dye-Doped Liquid Crystals" Z. Fan, H. Yoshida, T. Sakurai, M. Ozaki, 19th Optics of Liquid Crystals (OLC 2021), (on line Sept. 26-Oct.1, 2021)
  6. “Field-induced reorientation of three-dimensional photonic structure based on blue phase liquid crystal for computer-generated holograms” S.Y. Cho, H. Yoshida and M. Ozaki (Invited), SPIE Photonics West, Emerging Liquid Crystal Technologies XVI (on line, March 6-11, 2021)
  7. “Lattice orientation control of cholesteric blue phase and Its hologram application” M. Ozaki, S.Y. Cho, H. Yoshida (Keynote), SPIE Optics and Photonics, Liquid Crystals XX (on line, Aug. 24–28, 2020)
Related Website(s)
Contact
ozaki[at]eei.eng.osaka-u.ac.jp