• 한국응용과학기술학회지
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• 제16권4호
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• pp.281-286
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• 1999

We carried out this subject to observe photoisomerization using 8A5H and phospholipid(DLPC) containing azobenzene group which has reversible to cis-trans by light irradiation. We investigated the photoisomerization and property of the monolayer film on quartz substrate prepared by the mixture of 8A5H and phospholipid deposited using Langmuir-Blodgett(LB) method. It was found that the absorption spectrum of the 8A5H and phospholipid LB monolayer was induced to photoisomerization by alternate light irradiation. And the absorbance of both the solution of mixtures of 8A5H-phospholipid and LB film was reversibly changed by the acid-base exposure and alternate temperatures.

• 공업화학
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• 제2권4호
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• pp.311-329
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• 1991

산화주석전극 위에 LB 법에 의해 단분자층상으로 흡착된 양친매성 Os 착체의 전기화학적 거동을 살펴보았다. 또한 단분자막형태로 흡착된 redox 종의 전극반응의 이론식을 가역, 비가역, 준가역파에 대하여 검토하였고, 이들막이 진공증착된 $SnO_2$ 전극 위로 전이될 때, 그 전극에서 흐른 전체 전하를 cyclic voltammogram 의 그림적분법에 의해 구하였다. 그리고 이들 단분자막을 이용한 전자이동 중개반응의 응용면도 $Fe^{2+}$, TEMPOL 등을 이용해 해석하였다. 이들 측정된 cyclic voltammogram을 이론식으로부터 유도하여 분자들간의 상호작용 parameter를 고려해서 simultation 하였다. 이들로부터 구해진 parameter 들은 측정된 cyclic voltammogram 과 거의 일치함을 확인할수 있었다. 마지막으로 LB 법을 이용한 최근의 연구동향 및 응용분야를 소개하였다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권2호
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• pp.87-91
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• 2000

Metal ion complex of poly(N-(2,4-imidazoly)ethyl)maleimide-alt-l-octadecene (IMO-O) polymer used to confirm the possibility of molecular device made by Langmuir-Blodgett(LB) method. Electrical properties of the metal ion complex LB film were investigated using Metal/Insulator/Metal(MIM) structure. In the surface pressure-area($\pi$-A) isotherm of IMI-O polymer, the surface pressure at collapse point has a difference due to the interaction between polymer and metal ions. And the complex between polymer and metal ions could be verified through the investigation by Raman spectroscopy. In the current-voltage(I-V) property, the conductivity change of IMO-O polymer complexes due to the kinds of metal of metal ions couldn't be observed. However, the limiting area of molecules was changed by the concentration of the metal ions and the conductivity was increased with the occupied molecular area.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.868-870
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• 1992

Langmuir-Blodgett method is the best candidate for the development of the future molecular electronic devices. But, this molecular thin film devices requires the bulk properties that was influenced by the molecular arrangements and orientations. So, these are of current interest in molecular electronic device fabrications of new materials. In this experiment, the N-docosylquinolium-TCNQ LB films were deposited on the surface pressures of 30 mN/m and 45 mN/m. We measured the polarized UV/visible absorptions of deposited films for the study of the molecular arrangements and orientations. The polarized UV/visible absorption variation on the incidence and polarization angle of the LB film deposited on the surface pressure of 45 mN/m shown methodically variated. So, we concluded that the LB film deposited on 45 mN/mwas arranged better than that obtained at 30 mN/m.

• 한국전기전자재료학회논문지
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• 제15권8호
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• pp.695-701
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• 2002

Maxwell displacement current (MDC) measuring technique has been applied on the study of monolayers of fatty acid and polyamic acid mixture. The displacement current was generated from monolayers on the water surface by monolayer compression and expansion. Displacement current was generated when the area per molecule was about 132 $^2$and 115 $^2$just before the initial rise of the surface pressure during the 1st and 2nd mixed monolayer compressions cycle, respectively. Maxwell displacement currents were investigated in connection with mixed monolayer compression cycles. It was found that the maximum of MDC appeared at the molecular area just before the initial rise of surface pressure in compression cycles. Ultra thin film of fatty acid and polyamic acid mixture was prepared on the hydrophilic quartz plate by Langmuir-Blodgett (LB) method. The precursor LB film was heated in a vacuum dry oven at 12$0^{\circ}C$ in order to convert it into the LB film of polyimide. The absorption spectra of LB films were also induced photoisomerization by UV and visible light irradiation.

• Transactions on Electrical and Electronic Materials
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• 제6권1호
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• pp.18-21
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• 2005

Monolayers of lipids on a water surface have attracted much interest as models of biological membranes, but also as precursors of multilayer systems promising many technical applications. Until now, many methodologies have been developed in order to gain a better understanding of the relationship between the structure and function of the monolayers. Maxwell displacement current (MDC) measurement has been employed to study the dielectric property of Langmuirfilms. MDC flowing across monolayers is analyzed using a rod-like molecular model. A linear relationship between the monolayer compression speed a and the molecular area Am. Compression speed a was about 30, 40, and 50 mm/min. Langmuir-Blodgett(LB) layers of Arachidic acid deposited by LB method were deposited onto slide glass as Y-type film. The structure of manufactured device is Aul Arachidic acid! AI, the number of accumulated layers are $9{\sim}21$. Also, we then examined of the Metal-Insulator-Metal(MIM) device by means of I-V. The I-V characteristics of the device are measured from -3 to+3 V. The insulation property of a thin film is better as the distance between electrodes is larger.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1716-1718
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• 1996

It is well known that the metallophthalocyanine (MPcs) are sensitive to toxic gaseous molecules such as $NO_2$ and also chemically and thermally stable. Therefore, lots of MPcs are studied for the potential chemical sensor for $NO_2$ gas using quartz crystal microbalance(QCM) or electrical conductivity. In this study, thin films of octa(2-ethylhexyloxy) copper-phthalocyanine were prepared by Langmuir-Blodgett method and characterized by using UV-VIS spectrascopy and ellipsometry. Transfer condition, film characterization, and preliminary results of current-voltage(I-V) characteristics of these films exposed to $NO_2$ gas as a function of film thickness will be discussed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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• pp.162-165
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• 1996

It is well shown that the metallophthalocyanine (MPcs) are sensitive to tonic gaseous molecules such as NO$_2$ and also chemically and thermally stable. Therefore, lots of MPcs are studied for the potential chemical sensor for NO$_2$ gas using quartz crystal microbalance(QCM) or electrical conductivity. In this study, thin films of octa(2-ethylhexyloxy) copper-phthalocyaninc ware prepared by Langmuir-Blodgett method and characterized by using UV-VIS spectrascopy and cllipsometry. Transfer condition, film characterization, and preliminary results of current-voltage(I-V) characteristics of these films exposed to NO$_2$ gas as a function of film thickness will be discusscd.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1519-1521
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• 1997

In this paper, poly (N-(2-4-imidazolyl) ethyl) maleimide-alt-1-octadecene (IMI-O) polymer which can complex metal ion was used to confirm the possibility of molecular device made by Langmuir-Blodgett method. Metal/Insulator/Metal (MIM) device was fabricated for investigation of electric properties. In the ${\pi}$-A isotherm, surface pressure at collapse point was different as to the molecular weight of metal ion complexed respectively, In I-V characteristics, currents of MiM devices were different at the same voltage. It was thought that phenomena was occurred by interaction between function group and metal ion.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.49-52
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• 1999

We studied on the ultra thin DMPC by Langmuir-Blodgett(LB) method. The $\pi$ -A isotherm of the DMPC was measured at the air-water interface varying with the compressing speed and amounts of solutions for spreading. DMPC molecules have one phosphatidylcholine head group and two long alky groups with carbonyl group. Displacement currents generated during the compression of monolayers of DMPC on the surface of water were investigated. The molecular arrangement of deposited films were evaluated by measuring the absorption with the UVspectrometer. And we made structures of metal(Au)/DMPC/Metal(Au) and examined electron through DMPC LB films by means of current-voltage(I-V) measurement .