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Study on the LC Alignment on Vertical Alignment Polymer Surface using the AFM

AFM을 이용한 수직배향막 폴리머 표면위의 액정배향에 관한 연구

  • Published : 2003.06.01

Abstract

We have studied the alignment of liquid crystals (LCs) on homeotropic polymeric surface that is scanned using an atomic force microscope (AFM) tip by optical polarizing microscopy and computer simulation. The scanned areas on one substrate are 5 $\mu\textrm{m}$ ${\times}$ 5 $\mu\textrm{m}$, 10 $\mu\textrm{m}$ ${\times}$ 10 $\mu\textrm{m}$, and 20 $\mu\textrm{m}$ ${\times}$ 20 $\mu\textrm{m}$ and this substrate is assembled to another substrate coated. with homeotropic polymer. The fabricated micro-LC cell using two substrates does not show any hysteresis and disclination lines inside the nano-rubbing areas, while changing voltage up and down. This indicates that the pretilt angle exists in the areas, thereby forming a hybrid LC configuration. From the experimental and computer simulation results, we can understand that the AFM rubbing clearly changes surface status of homeotropic alignment layer and causes the pretilt angle to an initial scanning direction.

References

  1. 전기전자재료학회지 v.10 no.1 액정 디스플레이 소자의 분자배향 기술 서대식
  2. J. Appl. phys. v.62 The mechanism of polymer alignment of liquid crystal materials J.M.Geary;J.W.Goodby;A.R.Kmetz;J.S.Patel https://doi.org/10.1063/1.339124
  3. 전기전자재료학회논문지 v.12 no.5 광분 해반응을 이용한 액정배향 및 프리틸트각발생에 대한 어닐링효과 서대식;유문상;황정연;김형규
  4. 전기전자재료학회논문지 v.11 no.6 광배향 기술을 이용한 액정배향의 기구 및 폴리이미드의 분자 구조가 프리틸트각에 미치는 영향 서대식;황율연;이창훈
  5. Science v.265 Creation of liquid crystal waveguides with scanning force microscopy M.Ruetschi;P.Gruter;J.Funfschilling;H.J.Guntherodt https://doi.org/10.1126/science.265.5171.512
  6. J. Appl.Phys. v.80 no.6 Creation of submicron orientational structures in thin liquid crystal polymer layers M.Ruetschi;J.Funfschilling;H.J.Guntherodt https://doi.org/10.1063/1.363253
  7. Appl. Phys. Lett. v.71 no.20 Control of liquid crystal alignment by polyimide surface modification using atomic force microscopy A.J.Pidduck;S.D.Haslam;G.P.Bryan-Brown;R.Bannister;I.D.Kitely https://doi.org/10.1063/1.120212
  8. Appl. Phys. Lett. v.76 no.10 Ultra high-resolution liquid crystal display with gray scale B.Wen;M.P.Mahajan;C.Rosenblatt https://doi.org/10.1063/1.125996
  9. J. Appl. Phys. v.89 no.2 Mechanism of liquid crystal alignment on submicron patterned surfaces A.Rastegar;M.Skarabot;B.Blij;Th.Rasing https://doi.org/10.1063/1.1335649
  10. Appl. Phys. Lett. v.78 no.20 Surface alignment bistability of nematic liquid crystals by orientationally frustrated surface patterns J.H.Kim;M.Yoneya;J.Yamamoto;H.Yokoyama https://doi.org/10.1063/1.1371246
  11. Nanotechnology v.13 Nano-rubbing of a liquid crystal alignment layer by an atomic force microscope: a detailed characterization J.H.Kim;M.Yoneya;J.Yamamoto;H.Yokoyama https://doi.org/10.1088/0957-4484/13/2/301
  12. Proc. of the $5^{TH}$ KLCC`02 Nano-size liquid crystal waveguide using atomic force microscope W.C.Kim;S.Song;I.C.Jeon;J.H.Kim;M.H.Lee;S.H.Lee
  13. Proc. of the $9^{TH}$ IDW`02 Dynamically controllable micro-LC cell associated with surface modification using the AFM W.C.Kim;S.Song;I.C.Jeon;J.H.Kim;M.H.Lee;S.H.Lee