• Title/Summary/Keyword: Monolayer films

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A qualitative study of photomemory characteristics of the LB monolayer films of merocyanine dye (메로시아닌 색소 LB 단분자막의 광메모리 특성에 관한 정성적 연구)

  • 박태곤;권영수;강도열
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.44 no.7
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    • pp.889-894
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    • 1995
  • The structural changes of the merocyanine monolayer LB (Langmuir Blodgett) films were investigated. These changes were compared with the typical changes of the molecular structures of merocyanine solutions. The structural changes of quinoid/benzenoid were attained by exposure to atmosphere gases (HCl gas, N $H_{3}$ gas). The photoisomerization was not observed for the monolayer LB film due to their state of $M_{trans}$. But we could obtain the cis/trans photoisomerization characteristics reversibly, after the films were changed to M $H^{+}$$_{trans}$ structure by exposure to HCl gas. We also found that the cis/trans photoisomerization of the LB monolayer films show the memory characteristics.s.

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Surface Analysis of LB Films and Monolayer for IMI-O Polymer (IMI-O 고분자의 단분자막과 LB막에 대한 표면분석)

  • Jung, Sang-Burm;Yoo, Seung-Yeop;Park, Jae-Chul;Kwon, Young-Soo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.05b
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    • pp.265-268
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    • 2000
  • We fabricated an IMI-O polymer containing an imidazole group that could form a complex structure between the monolayer and the metal ions at the air-water interface. Also. the monolayer behavior at the air-water interface and the surface morphology of metal-complexed Langmuir-Blodgett(LB) films were investigated by using Brewster angle microscopy(BAM) and Scanning Maxwell-stress Microscopy(SMM). The difference in the BAM and SMM images between the pure water and the aqueous metal ions is attributed to the interactions of the copolymers with the metal ions at the interface and the consequent change of the monolayer organization.

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Fabrication of transparent conductive thin films with Ag mesh shape using the polystyrene beads monolayer

  • Jung, Taeyoung;Choi, Eun Chang;Hong, Byungyou
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.313-313
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    • 2016
  • Transparent conductive oxide (TCO) films have many disadvantages, such as rarity, possible exhaustion, process temperature limitations, and brittleness on a flexible substrate. In particular, as display technology moves toward flexible displays, TCO will become completely unsuitable due to its brittleness. To address theses issue, many researchers have been studying TCO substitutes. In recent efforts, metal nanowires, conducting polymers, carbon nanotube networks, graphene films, hybrid thin films, and metal meshes/grids have been evaluated as candidates to replace TCO electrodes. In this study, we fabricated the TCO film with Ag meshes shape using polystyrene (PS) beads monolayer on the substrate. The PS beads were used as a template to create the mesh pattern. We fabricated the monolayer on the flexible substrate (PES) with the well-aligned PS beads. Electrodes with Ag mesh shape were formed using this patterned monolayer. We could fabricated the Ag mesh electrode with the sheet resistance with $8ohm{\Omega}/{\Box}$.

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Effect of self-assembled monolayer and aluminum oxide ALD film on a PMMA substrate

  • Shin, Sora;Park, Jongwan
    • Journal of Ceramic Processing Research
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    • v.19 no.6
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    • pp.525-529
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    • 2018
  • The antireflective (AR) coated poly methyl methacrylate (PMMA) substrate was deposited by atomic layer deposition (ALD) on a self-assembled monolayer (SAM) to improve hydrophobicity and mechano-chemical properties of organic thin films. The water contact angles (WCA) were tested to characterize the surface wettability of SAM octadecyltrichlorosilane (OTS) films. Results showed that a contact angle of $105.9^{\circ}$ was obtained for the SAM films with an annealing process, and the highest WCA of $120^{\circ}$ was achieved for the films prepared by the SAM and ALD multi-process. The surface morphology of the SAM films with different assembly times and varying number of ALD cycles was obtained by atomic force microscopy (AFM). The maximum light transmittance for the SAM films on the PMMA substrate reached 99.9% at a wavelength of 450 nm. It was found that the SAM surfaces were not affected at all by the ALD process.

Electrical Properties of Both a Monolayer at the Air/Water Interface and a Langmuir-Blodgett Film Sandwiched Between Aluminum Electrodes (수면상의 고분자막과 알루미늄 전자간의 Langmuir-Blodgett막에 대한 전기적 특성)

  • Mitsumasa Iwamoto;Kang, Dou-Yol
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.38 no.1
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    • pp.35-42
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    • 1989
  • Electrical properties of both a monolayer at the air/water interface and Langmuir-Blodgett films sandwiched between aluminum electrodes are studied using a current-measuring technique. A change in induced charges on an electrode suspended in the air was measured in combination with the surface area isotherm in the electrical measurement of the monolayer. A change in induced charges on an electrode is measured while heating the sample in the electrical measurement of the LB films. From both measurements, we elucidated that a spontaneous polarization plays very important role in the electrical properties of both a monolayer at the air/water interface and LB films sandwiched between aluminum electrodes.

The Electrical Conductivity and Electrochemical Characteristics of Amphiphilic Milecules Multilayer Film confined with Hetero Type (양친매성 다중층막의 전기적 도전성 및 전기적 특성)

  • 최인희;박수길;임기조;이주성
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.05a
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    • pp.269-272
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    • 1996
  • The electrochemical behavior of Ru complex and PD complex monolayer, deposited on conductive substrate by the Langmuir-Blodgett(LB) technique as monolayer and multilayer, has been studied by cyclic voltammetry. Monolayer films show stable reversible state. Atomic resolution imaging of LB highly-conductive, environmently stable organic films has been obtained by atomic force microscopy (AFM) showing their closely packed structure,

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Morphology and Surface Magnetism of Ultrathin Fe Films on Pd(111)

  • Park, Jae-Hoon;Kim, Wookje;Kim, Wondong;Kim, Jae-Young;Hoon Koh;S.J. Oh
    • Proceedings of the Korean Vacuum Society Conference
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    • 2000.02a
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    • pp.141-141
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    • 2000
  • In situ surface magneto-optic Kerr effect(SMOKE), X-ray photoelectron spectroscopy(XPS) and low energy electron diffraction(LEED) were used to study magnetic and structural properties of ultrathin Fe films grown on the Pd(111) surface. The SMOKE measurement showed strong enhancement of ferromagnetism after proper annealing process. Simultaneous changes in morphology was checked by LEED and XPS. After room temperature Fe deposition. longitudinal magnetization appeared above a critical thickness between 2.0 and 2.5 monolayers. When annealed at 450K, 2.0 monolayer Fe film exhibited boty longitudinal and polar magnetizations while 3.0 and 5.5 monolayer films showed little changes. After annealing at 600K, both magnetizations were totally destroyed in 2.0 monolayer film, but longitudinal magnetization was enhanced in 3.0 monolayer film. In the case of 5.5 monolayer film, it was only after 660K annealing that the enhancement of the longitudinal magnetization was observed. It was concluded that the surface flatness and the amount of intermixing were critical in the development of surface magnetism of this system.

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A Study on Displacement Current Characteristics of DLPC Monolayer (I) (DLPC 인지질 단분자막의 변위전류 특성 연구 (I))

  • Song, Jin-Won;Lee, Kyung-Sup;Choi, Yong-Sung
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.1
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    • pp.117-122
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    • 2007
  • LB method is one of the most interesting technique to arrange certain molecular groups at precise position relative to others. Also, the LB deposition technique can fabricate extremely thin organic films with a high degree of control over their thickness and molecular architecture. In this way, new thin film materials can be built up at the molecular level, and the relationship between these artificial structures and the properties of materials can be explored. In this paper, evaluation of physical properties was made for dielectric relaxation phenomena by the detection of the surface pressures and displacements current on the monolayer films of phospolipid monomolecular DLPC. Lipid thin films were manufacture by detecting deposition for the accumulation and the current was measured after the electric bias was applied across the manufactured MIM device. It is found that the phospolipid monolayer of dielectric relaxation takes a little time and depend on the molecular area. When electric bias is applied across the manufactured MIM device by the deposition condition of phospolipid mono-layer, it wasn't breakdown when the higher electric field to impress by increase of deposition layers.

Stimulus Current of Mixed Organic Thin Films (혼합 유기박막의 자격 전류)

  • Cho, Su-Young;Lee, Kyung-Sup
    • Proceedings of the KIEE Conference
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    • 2000.11c
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    • pp.464-466
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    • 2000
  • In the study We measured the MDC across lipidazobenzene monolayer system was the substrate. We discuss the cis-trans isomerization in Langmuir-Blodgett(LB) films and examine the relationship between the structure of mixed LB films and the generation of MDCs due to photoisomerization. As results, mixed induce monolayer of view to memory and switching, it's own function by particles level think. Also, transmission results of stimulus signal it's form by current to appear.

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A length dependance of monolayer films of long-chain fatty acids (장쇄지방산의 길이에 따른 단분자막의 특성 변화)

  • 구창권;김무군;송경호;박태곤
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.05a
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    • pp.38-42
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    • 1996
  • The pressure-area isotherm of monolayer at the air-water interface were obtained and the LB films were fabricated onto a quartz slides and quartz crystal by conventional Langmuir-Blodggett(LB) method. The UV absorption spectra of Langmuir-Blodggett(LB) film on quartz slides and spectrum of monolayer formed on quartz crystal have been measured. The photoisomerization of the long-chain fatty avid containing azobenzene were obtained by the application of UV and visible light. The reversibility of photoisomerization were more clear difference when the number of C$\_$n/ increased. At the pressure-area isotherms, the value of surface pressure increment were decreased when the number of C$\_$n/ increased, A surface pressure of 20mN/m was obtained as a proper one for a film deposition. The photoisomerization at LB films were also obtained by application of UV and visible light. So the LB film of long-chain fatty acid containing azobenzene has possibility to being applies to functional molecular devices such as photomemory and light switching.

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