• Title/Summary/Keyword: Pretilt angle

Search Result 238, Processing Time 0.026 seconds

Study of Properties of High-K Strontium Oxide Alignment Layer Using Solution Process for Low Power Mobile Information Device (저전력 휴대용 통신단말을 위한 Solution Process를 이용한 고 유전율 Strontium Oxide 배향막의 특성 연구)

  • Han, Jeong-Min;Kim, Won-Bae
    • Journal of Satellite, Information and Communications
    • /
    • v.10 no.2
    • /
    • pp.90-94
    • /
    • 2015
  • We stuidied liauid crystal alignment treatment using solution process for making thin oxide layer in liquid crystal display. It is the one of very effient and popular process in making thin oxide layer in electronical industrial fields. Particularly, this process has highly potential value in liquid crystal display industrial fields because it cause automatically induced alignment process without tranditional alignment process in liquid crystal alignment process. We made several different kinds of mol density solutions using strontium oxide solution. And those solutions were treated for solidification layers using annealing process for 2 hours. And we stuided pretilt angle properties of these alignment layers of strontium oxide for clarifying the relationship of liquid crystal molecules and thin strontium oxide layer. And we also tested the existence of strontium oxide thin layer on substrate using XPS measurement. We expected the hig gain of electro-optical properties in liquid crystal display using strontium oxide thin layer because it has high K property material than the other metal-based oxide layers. In this results, we measured 1.447 to 1.613 thresholds volts as 0.1 mol to 0.4 mol density in 0.1 mol density steps. This is significant better characteristics than conventional liquid crystal display as higher than 1.85 thresholds volts. And it make possible to making next-generation liquid crystal display which present low-power consumption and wide gray scale in liquid crystal display.

Liquid Crystal Alignment Effects on Nitrogen-doped Diamond like Carbon Layer by Ion Beam Alignment Method

  • Han, Jeong-Min;Choi, Sung-Ho;Kim, Byoung-Yong;Han, Jin-Woo;Kim, Jong-Hwan;Kim, Young-Hwan;Hwang, Jeoung-Yeon;Lee, Sang-Keuk;Ok, Chul-Ho;Seo, Dae-Shik
    • Transactions on Electrical and Electronic Materials
    • /
    • v.8 no.1
    • /
    • pp.46-50
    • /
    • 2007
  • We have studied the nematic liquid crystal (NLC) alignment effects on a nitrogen-doped diamond-like carbon (NDLC) thin film layer with ion beam irradiation. The pretilt angle for NLC on the NDLC surface with ion beam exposure was observed below 1 degree. Also, we had the good LC alignment characteristics on the NDLC thin films with ion beam exposure of 1800 eV. In thermal stability experiments, the alignment defect of the NLC on the NDLC surface with ion beam irradiation above annealing temperature of $250^{\circ}C$ can be observed. Therefore, the good thermal stability and LC alignment for NLC by ion beam aligned NDLC thin films can be achieved.

Liquid Crystal Aligning Capabilities Treated on Organic Overcoat Thin Films by Ion Beam Irradiation Method

  • Han, Jeong-Min;Kim, Byoung-Yong;Kim, Jong-Yeon;Kim, Young-Hwan;Han, Jin-Woo;Hwang, Jeoung-Yeon;Lee, Sang-Keuk;Kang, Dong-Hun;Ok, Chul-Ho;Seo, Dae-Shik
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.20 no.3
    • /
    • pp.245-249
    • /
    • 2007
  • The liquid crystal display (LCD) applications treated on the organic overcoat thin film surfaces by ion beam irradiation was successfully studied. The good LC aligning capabilities treated on the organic overcoat thin film surfaces with ion beam exposure of $60^{\circ}$ for 2 min above ion beam energy of 1200 eV can be achieved. But, the alignment of defect of NLC on the organic overcoat surface at low energy of 600 eV was measured. The pretilt angle of NLC on the organic overcoat thin film surface with ion beam exposure of $60^{\circ}$ for 2 min at energy of 1800 eV was measured about 1 degree. Finally, the good thermal stability of LC alignment on the organic overcoat thin film surface with ion beam exposure of $60^{\circ}$ for 2 min until annealing temperature of $200^{\circ}C$ can be measured.

Study on Electro-Optical Specific of Polyimide and Organic Overcoat (PI와 유기 절연막 과의 전기광학 특성 비교에 관한 연구)

  • Kim, Byoung-Yong;Kim, Jong-Hwan;Han, Jeong-Min;Kim, Young-Hwan;Kang, Dong-Hoon;Kim, Jong-Yeon;Ok, Chul-Ho;Seo, Dae-Shik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2007.06a
    • /
    • pp.376-376
    • /
    • 2007
  • In Liquid Crystal Display (LCD) manufacturing, the organic over coat materials over coat materials for insulation layer of color filter with acryl ate was widely used. Therefore, we approach that the organic overcoat material can use to insulation layer for color filter and liquid crystal (LC) alignment layer in this research. The LC aligning capabilities was successful stuided for the first time. The organic overcoat layer and polymer layer was coated by spin-coating. In order to characterize the LC alignment, electric optic and residual DC and atomic force microscopy (AFM) image was used. The good LCD aligning capabilities treated on the organic overcoat thin film surfaces with ion beam exposure of $45^{\circ}$ above ion beam energy density of 1200 eV can be achieved. Also the good LCD alignment capabilities treated polymer on surfaces with ion beam exposure of $45^{\circ}$ above ion beam energy density of 1800 eV can be achieved. Comparing electro-optical characteristics between the Polyimide (PI) and the overcoat, the resultant transmittance of the overcoat considerably matched that of the PI and the residual DC also exhibited similar features with the PI.

  • PDF

Parallel pattern fabrication on metal oxide film using transferring process for liquid crystal alignment (전사 공정을 이용한 산화막 정렬 패턴 제작과 액정 배향 특성 연구)

  • Oh, Byeong-Yun
    • Journal of IKEEE
    • /
    • v.23 no.2
    • /
    • pp.594-598
    • /
    • 2019
  • We demonstrate an alternative alignment process using transferring process on solution driven HfZnO film. Parallel pattern is firstly fabricated on a silicon wafer by laser interference lithography. Prepared HfZnO solution fabricated by sol-gel process is spin-coated on a glass substrate. The silicon wafer with parallel pattern is placed on the HfZnO film and annealed at $100^{\circ}C$ for 30 min. After transferring process, parallel grooves on the HfZnO film is obtained which is confirmed by atomic force microscopy and scanning electron microscopy. Uniform liquid crystal alignment is achieved which is attributed to an anisotropic characteristic of HfZnO film by parallel grooves. The liquid crystal cell exhibited a pretilt angle of $0.25^{\circ}$ which showed a homogeneous alignment property.

Nanostructuring the Polyimide Alignment Layer and Uniform Liquid Crystal Alignment by Solvent Assisted Micromolding (Solvent Assisted Micromolding을 이용한 Polyimide 나노구조 형성 및 이를 통한 균일 액정 배향)

  • Kim, Jongbok
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
    • /
    • v.12 no.1
    • /
    • pp.72-77
    • /
    • 2019
  • The display that provides information to us through the visual sense is a very important information transmission means by intuitively transmitting information, and the liquid crystal display (LCD) is the most widely used information transmission display. In this paper, we studied solvent assisted micromolding as an alternative for the rubbing that is essential to align the liquid crystals in LCD and successfully aligned the liquid crystal molecules by constructing the nanostructures on conventional polyimide alignment layer. When generating the nanostructures on the polyimide film, there was a competitive correlation between the dissolution effect of the polymer by the solvent and the capillary effect of the polyimide molecules into the nanostructures of the mold depending on the process temperature. It was possible to form nanostructures with high step by deriving the optimum temperature. These nanostructures were able to align the liquid crystal molecules uniformly and demonstrated that they could form a desirable pretilt angle.

Electro-optical characteristic analysis of liquid crystal cell using UV-treated self assembled monolayer (UV 처리된 자기 조립 단분자막을 사용한 액정 셀의 전기광학특성 분석)

  • Chan-Woo Oh;Hong-Gyu Park
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
    • /
    • v.16 no.2
    • /
    • pp.109-115
    • /
    • 2023
  • In this paper, we demonstrated the orientation characteristics of liquid crystals using UV-treated FSAM as alignment layer. Moreover we confirmed the FSAM properties before and after UV treatment on indium tin oxide (ITO) glass substrates using physicochemical analysis. The hydrophobic property of the FSAM surface is change to hydrophilic through UV treatment. After UV treatment the LC molecules also were uniformly and horizontally aligned on the FSAM surfaces and the pretilt angle was obviously changed 90° degrees to 0° degrees. EO characteristic of TN cell which was fabricated with UV-treated FSAM was faster response time compare to conventional PI layer. The FSAM before and after UV treatment has a superior application potential as the LC alignment layer for LCD, potentially replacing the conventional polyimide layer.

Properties of liquid crystal alignment layers exposued to ion-beam irradiation enemies (이온빔 에너지에 따른 액정배향막의 전기광학적 특성연구)

  • Oh, Byeong-Yun;Lee, Kang-Min;Park, Hong-Gyu;Kim, Byoung-Yong;Kang, Dong-Hun;Han, Jin-Woo;Kim, Young-Hwan;Han, Jeong-Min;Lee, Sang-Keuk;Seo, Dae-Shik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2007.11a
    • /
    • pp.430-430
    • /
    • 2007
  • In general, polyimides (PIs) are used in liquid crystal displays (LCDs) as alignment layer of liquid crystals (LCs). Up to date, the rubbing alignment technique has been widely used to align liquid crystals on the PI surface, which is suitable for mass-production of LCDs because of its simple process and high productivity. However, this method has some disadvantages. Rubbed PI surfaces include the debris left by the cloth and the generation of electrostatic charges during rubbing process. Therefore, rubbing-free techniques for LC alignment are strongly required in LCD technology. In this experiment, PI was uniformly coated on indium-tin-oxide electrode substrates to form LC alignment layers using a spin-coating method and the PI layers were subsequently imidized at 433 K for 1 h. The thickness of the PI layer was set at 50 nm. The LC alignment layer surfaces were exposed to an $Ar^+$ ion-beam under various ion-beam energies. The antiparallel cells and twisted-nematic (TN) cells for the measurement of pretile angle and electro-optical characteristics were fabricated with the cell gap of 60 and $5\;{\mu}m$, respectively. The LC cells were filled with nematic LC (NLC, MJ001929, Merck) and were assembled. The NLC alignment capability on ion-beam-treated PI was observed using photomicroscope and the pretilt angle of the NLC was measured by the crystal-rotation method at room temperature. Voltage-transmittance (V-T) and response time characteristics of the ion-beam irradiated TN cell were measured by a LCD evaluation system.

  • PDF