SpringerLink
Log in

Facile Approach to Directional Alignment of Indium-Doped Strontium Oxide Film and Improved Liquid Crystal System Application

  • Original Research Article
  • Published:
Journal of Electronic Materials Aims and scope Submit manuscript

Abstract

In this study, we describe the characterization and applicability of the liquid crystal (LC) system of brush-coated indium strontium oxide (InSrO) film. To achieve this aim, the film curing temperature was adjusted and the surface morphology was examined using atomic force microscopy and corresponding line profile data. In particular, we revealed a nano/microgroove anisotropic surface structure on the film after curing at 230°C, which was derived from the shear stress generated during movement of the wet brush hairs and subsequent active thermal oxidation of InSrO. In addition, x-ray photoelectron spectroscopy confirmed the presence of a well-formed InSrO film on the substrate. The film also exhibited hydrophilic properties at higher curing temperatures along with an amorphous structure. The InSrO film represented high optical transmittance to the LC system, and we confirmed the uniform and homogeneous LC alignment state using polarized optical microscopy and pre-tilt angle analyses. The oriented anisotropic film structure induced the alignment of LCs on the surface through geometric constraints. The InSrO film also exhibited advanced electro-optical performance with a fast response time and low operating voltage compared to the polyimide layer conventionally used in LC systems. From these results, we expect that brush-coated InSrO film will be a good alternative in advanced LC systems.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Subscribe and save

Springer+ Basic
EUR 32.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or Ebook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price includes VAT (Germany)

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8

Similar content being viewed by others

Data Availability

The raw/processed data required to reproduce these findings are available from the corresponding authors upon reasonable request.

References

  1. Y. Garbovskiy, Switching between purification and contamination regimes governed by the ionic purity of nanoparticles dispersed in liquid crystals. Appl. Phys. Lett. 108, 121104 (2016). https://doi.org/10.1063/1.4944779.

    Article  CAS  Google Scholar 

  2. S.-R. Son, J. An, J.-W. Choi, S. Kim, J. Park, and J.H. Lee, Surface-anchored alkylated graphene oxide as a two-dimensional homeotropic alignment layer for nematic liquid crystals. Mater. Today Commun. 28, 102539 (2021). https://doi.org/10.1016/j.mtcomm.2021.102539.

    Article  CAS  Google Scholar 

  3. T.-T.-T. Nguyen, T.-N. Luu, D.-H. Nguyen, and T.-T. Duong, Comparative study on backlighting unit using CsPbBr 3 nanocrystals/KSFM phosphor + Blue LED and commercial WLED in liquid crystal display. J. Electron. Mater. 50, 1827 (2021). https://doi.org/10.1007/s11664-021-08775-1.

    Article  CAS  Google Scholar 

  4. W.-K. Lee, Y.-S. Choi, Y.-G. Kang, J. Sung, D.-S. Seo, and C. Park, Super-fast switching of twisted nematic liquid crystals on 2D single wall carbon nanotube networks. Adv. Funct. Mater. 21, 3843 (2011). https://doi.org/10.1002/adfm.201101345.

    Article  CAS  Google Scholar 

  5. X. Yan, F.W. Mont, D.J. Poxson, M.F. Schubert, J.K. Kim, J. Cho, and E.F. Schubert, Refractive-index-matched indium–tin-oxide electrodes for liquid crystal displays. Jpn. J. Appl. Phys. 48, 120203 (2009). https://doi.org/10.1143/JJAP.48.120203.

    Article  CAS  Google Scholar 

  6. T.-H. Lin and H.-C. Jau, Electrically controllable laser based on cholesteric liquid crystal with negative dielectric anisotropy. Appl. Phys. Lett. 88, 061122 (2006). https://doi.org/10.1063/1.2168259.

    Article  CAS  Google Scholar 

  7. G. Kocakülah and O. Köysal, Electro-optical, dielectric and morphological properties of a cholesteric liquid crystal light shutter: the influence of azo dye and quantum dot nanoparticles. J. Electron. Mater. 51, 6864 (2022). https://doi.org/10.1007/s11664-022-09913-z.

    Article  CAS  Google Scholar 

  8. B.I. Outram and S.J. Elston, Spontaneous and stable uniform lying helix liquid-crystal alignment. J. Appl. Phys. 113, 043103 (2013). https://doi.org/10.1063/1.4784016.

    Article  CAS  Google Scholar 

  9. S.-W. Oh and T.-H. Yoon, Elimination of light leakage over the entire viewing cone in a homogeneously-aligned liquid crystal cell. Opt. Express 22, 5808 (2014). https://doi.org/10.1364/OE.22.005808.

    Article  Google Scholar 

  10. Y.J. Kim, Z. Zhuang, and J.S. Patel, Effect of multidirection rubbing on the alignment of nematic liquid crystal. Appl. Phys. Lett. 77, 513 (2000). https://doi.org/10.1063/1.127028.

    Article  CAS  Google Scholar 

  11. S. Varghese, S. Narayanankutty, C.W.M. Bastiaansen, G.P. Crawford, and D.J. Broer, Patterned alignment of liquid crystals by μ-rubbing. Adv. Mater. 16, 1600 (2004). https://doi.org/10.1002/adma.200306536.

    Article  CAS  Google Scholar 

  12. G.M. Wu, C.Y. Liu, and A.K. Sahoo, RF sputtering deposited a-IGZO films for LCD alignment layer application. Appl. Surf. Sci. 354, 48 (2015). https://doi.org/10.1016/j.apsusc.2015.04.153.

    Article  CAS  Google Scholar 

  13. J.L. Janning, Thin film surface orientation for liquid crystals. Appl. Phys. Lett. 21, 173 (1972). https://doi.org/10.1063/1.1654331.

    Article  CAS  Google Scholar 

  14. L. Zhang, Z. Peng, L. Yao, C. Fei, F. Lv, and L. Xuan, Photoalignment of liquid crystals by cinnamate polyelectrolyte layer-by-layer ultrathin film. Appl. Surf. Sci. 253, 3372 (2007). https://doi.org/10.1016/j.apsusc.2006.05.050.

    Article  CAS  Google Scholar 

  15. D.W. Lee, J.H. Lee, E.M. Kim, G.S. Heo, D.H. Kim, J.Y. Oh, Y. Liu, and D.-S. Seo, Surface modification of a poly(ethylene-co-vinyl acetate) layer by ion beam irradiation for the uniform alignment of liquid crystals. J. Mol. Liq. 339, 116700 (2021). https://doi.org/10.1016/j.molliq.2021.116700.

    Article  CAS  Google Scholar 

  16. J.V. Haaren, Wi** out dirty displays. Nature 411, 29 (2001). https://doi.org/10.1038/35075178.

    Article  Google Scholar 

  17. O. Bierwagen, Indium oxide—a transparent, wide-band gap semiconductor for (opto)electronic applications. Semicond. Sci. Technol. 30, 024001 (2015). https://doi.org/10.1088/0268-1242/30/2/024001.

    Article  CAS  Google Scholar 

  18. E.-G. Park, C.-W. Oh, and H.-G. Park, Improvement of the electro-optical properties of nematic liquid crystals doped with strontium titanate nanoparticles at various do** concentrations. Liq. Cryst. 47, 136 (2020). https://doi.org/10.1080/02678292.2019.1633430.

    Article  CAS  Google Scholar 

  19. C.C. Mell and S.R. Finn, Forces exerted during the brushing of a paint. Rheol. Acta 4, 260 (1965). https://doi.org/10.1007/BF01973663.

    Article  Google Scholar 

  20. S.-S. Kim, S.-I. Na, J. Jo, G. Tae, and D.-Y. Kim, Efficient polymer solar cells fabricated by simple brush painting. Adv. Mater. 19, 4410 (2007). https://doi.org/10.1002/adma.200702040.

    Article  CAS  Google Scholar 

  21. A.W. Adamson, Physical Chemistry of Surfaces 5th ed., Wiley-Interscience, 1990.

  22. J. Li, Y. Pan, C. **ang, Q. Ge, and J. Guo, Low temperature synthesis of ultrafine α-Al2O3 powder by a simple aqueous sol–gel process. Ceram. Int. 32, 587 (2006). https://doi.org/10.1016/j.ceramint.2005.04.015.

    Article  CAS  Google Scholar 

  23. H.-G. Park, J.-J. Lee, K.-Y. Dong, B.-Y. Oh, Y.-H. Kim, H.-Y. Jeong, B.-K. Ju, and D.-S. Seo, Homeotropic alignment of liquid crystals on a nano-patterned polyimide surface using nanoimprint lithography. Soft Matter 7, 5610 (2011). https://doi.org/10.1039/C1SM05083D.

    Article  CAS  Google Scholar 

  24. K.-H. Chen, W.-Y. Chang, and J.-H. Chen, Measurement of the pretilt angle and the cell gap of nematic liquid crystal cells by heterodyne interferometry. Opt. Express 17, 14143 (2009). https://doi.org/10.1364/OE.17.014143.

    Article  CAS  Google Scholar 

  25. K.Y. Han, T. Miyashita, and T. Uchida, Accurate measurement of the pretilt angle in a liquid crystal cell by an improved crystal rotation method. Mol. Cryst. Liq. Cryst. Sci. Technol. Sect. A-Mol. Cryst. Liq. Cryst. 241, 147 (1994). https://doi.org/10.1080/10587259408029751.

    Article  CAS  Google Scholar 

  26. J.-I. Fukuda, M. Yoneya, and H. Yokoyama, Surface-groove-induced azimuthal anchoring of a nematic liquid crystal: berreman’s model reexamined. Phys. Rev. Lett. 98, 187803 (2007). https://doi.org/10.1103/PhysRevLett.98.187803.

    Article  CAS  Google Scholar 

  27. D.W. Berreman, Solid surface shape and the alignment of an adjacent nematic liquid crystal. Phys. Rev. Lett. 28, 1683 (1972). https://doi.org/10.1103/PhysRevLett.28.1683.

    Article  CAS  Google Scholar 

  28. H. Kikuchi, J.A. Logan, and D.Y. Yoon, Study of local stress, morphology, and liquid-crystal alignment on buffed polyimide surfaces. J. Appl. Phys. 79, 6811 (1996). https://doi.org/10.1063/1.361502.

    Article  CAS  Google Scholar 

  29. B. Chae, S.B. Kim, S.W. Lee, S.I. Kim, W. Choi, B. Lee, M. Ree, K.H. Lee, and J.C. Jung, Surface morphology, molecular reorientation, and liquid crystal alignment properties of rubbed nanofilms of a well-defined brush polyimide with a fully rodlike backbone. Macromolecules 35, 10119 (2002). https://doi.org/10.1021/ma020639i.

    Article  CAS  Google Scholar 

  30. H.-C. Jeong, J.H. Lee, J. Won, B.Y. Oh, D.H. Kim, D.W. Lee, I.H. Song, Y. Liu, and D.-S. Seo, One-dimensional surface wrinkling for twisted nematic liquid crystal display based on ultraviolet nanoimprint lithography. Opt. Express 27, 18094 (2019). https://doi.org/10.1364/OE.27.018094.

    Article  CAS  Google Scholar 

  31. D.H. Kim, D.W. Lee, J.Y. Oh, J. Won, H.-C. Jeong, and D.-S. Seo, Nanostructured hafnium-doped strontium oxide film for homeotropic/homogeneous convertible liquid crystal alignment depending on the curing temperature. Int. J. Smart Nano Mater. 13, 597 (2022). https://doi.org/10.1080/19475411.2022.2116736.

    Article  Google Scholar 

Download references

Acknowledgments

This research was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (No. 2022R1F1A106419212).

Author information

Authors and Affiliations

  1. Department of Electrical and Electronic Engineering, Jeonju University, 303 Cheonjam-ro, Wansan-gu, Jeonju-si, 55069, Jeollabuk-do, Korea

    Dong Wook Lee

  2. IT Nano Electronic Device Laboratory, Department of Electrical and Electronic Engineering, Yonsei University, Seodaemun-gu, Seoul, 120-749, South Korea

    Dong Hyun Kim, ** Young Oh, Da Bin Yang, Joonhoon Won & Dae-Shik Seo

  3. Department of Smart Electric, Korea Polytechnic, 23, Yeomjeon-ro, 333beon-gil, Nam-gu Incheon, 22121, South Korea

    Dae-Hyun Kim

  4. College of Information Science and Technology, Donghua University, 2999 North Renmin Road, Songjiang District, Shanghai, 201620, China

    Yang Liu

Authors
  1. Dong Wook Lee
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Dong Hyun Kim
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. ** Young Oh
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Da Bin Yang
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Joonhoon Won
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Dae-Hyun Kim
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Yang Liu
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Dae-Shik Seo
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

DWL: Conceptualization, formal analysis, and writing the original draft. DHK: Investigation and validation. JYO: Investigation and visualization. DBY: Validation and visualization. JW: Resources and validation. DHK: Investigation and visualization. YL: Formal analysis and supervision. DSS: Funding acquisition and project administration.

Corresponding authors

Correspondence to Yang Liu or Dae-Shik Seo.

Ethics declarations

Conflict of interest

The authors declare that they have no conflict of interest.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Lee, D.W., Kim, D.H., Oh, J.Y. et al. Facile Approach to Directional Alignment of Indium-Doped Strontium Oxide Film and Improved Liquid Crystal System Application. J. Electron. Mater. 52, 6225–6233 (2023). https://doi.org/10.1007/s11664-023-10560-1

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11664-023-10560-1

Keywords

Search

Navigation