• Korean Journal of Materials Research
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• v.10 no.8
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• pp.564-568
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• 2000

Langmuir-Blodgett(LB) 법은 미래의 분자전자소자를 위한 가장 유력한 수단이며, 이러한 분자박막 소자는 그 성질이 분자는 배향에 영향을 박데 되므로 현재 새로운 물질을 이용하여 분자전자소자의 제작에 있어 관심을 모으고 있다. 본 연구에서는 (N-docosyl quinolinium)-TCNQ(1:2) 전하 이동 착물 LB 막의 분자 배향을 UV/vis 편광흡수 스펙트럼과 FT-IR transmission 및 reflection-absorption 스펙트럼의 흡수강도를 비교하여 정량적으로 평가하였다. 그 결과 TCNQ의 transition dipole moment의 각은 약 56~58。 였으며, 알킬 고리의 경사각은 약 11.1~13。였다. 제작된 Z-형 LB 막의 표면은 고압에서 중앙 높이 차가 3~4$\AA$으로 평탄하였다.

• Korean Journal of Materials Research
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• v.9 no.12
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• pp.1229-1233
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• 1999

In this research, We fabricated Langmuir-Blodgett(LB) ultra-thin films with (N-docosyl quinolinium)- TCNQ(1:2) complex. The characteristics ${\pi}$-A isotherms were studied to find optimum conditions of deposition by varing temperature of subphase, compression speed of barrier and amount of spreading solution. Film formation was verified by measuring transfer ratio, maximum absorption of UV-vis spectra, capacitance and ellipsometry. From the results, it was concluded that the LB film formed well with molecular oder was fabricated.

• Polymer Science and Technology
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• v.3 no.6
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• pp.489-505
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• 1992

• Electrical & Electronic Materials
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• v.11 no.1
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• pp.80-85
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• 1998

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.8
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• pp.581-586
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• 1998

This paper describes athermally stimulated displacement current (TSDC) of arachidic acid(AA) and polyamic acid alkylamine salts(PAAS) Langmuir-Blodgett(LB) films, which is a precursor of polyimide(PI). The TSDC measurements of AA LB film were performed from temperature to about 11$0^{\circ}C$ at a rate of 0.2$^{\circ}C$/ｓ inside a vacuum chamber for a reference. And the TSDC measurements PAAS LB film were performed from room temperature to about 25$0^{\circ}C$ and temperature was increased at the same rate as that of AA LB film. They show that there are TSDC peaks at about 7$0^{\circ}C$ in the arachidic acid LB films, and at about 7$0^{\circ}C$ and 16$0^{\circ}C$ in the PAAs LB films. Results of these measurements indicate the one small peak at 7$0^{\circ}C$ is resulted from a softening of the alkyl group and the large peak at 16$0^{\circ}C$ is possibly due to dipole of C-O group in the PASS molecule. We have calculated the vertical component of the AA and PAAs L film out of the TSDC curves. It shows that the dipole moment of the AA LB film is about 70-mD at 7$0^{\circ}C$. And the dipole moment of PAAS LB film is about 040mD at 7$0^{\circ}C$ and about 200mD at 16$0^{\circ}C$ in the first measurement of TSDC. In the second measurement of TSDC of PASS LB film after cooling down to room temperature, the TSDC peaks are almost disappeared.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.752-755
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• 2002

Since Metallo-Porphyrin (MP) is very interesting compound due to its unique electronic and redox properties and it is also chemically and thermally stable, MP has been studied for potential memory and switching devices. In this study, thin films of 5,10,15,20 - Tetrakis - Octadecyloxymethylphenyl - Porphyrin - Zn(II) (Zn-TPP) were prepared by the Langmuir-Blodgett (LB) method and characterized by using UV/vis absorption spectroscopy and cyclic voltammetry. It was found that the proper transfer surface pressure for film deposition was 25 mN/m and the limiting area per molecule was $135{\AA}^2$/molecule. The current-voltage (I-V) characteristics of these films were investigated.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.1090-1093
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• 2003

최근에 각광을 받고 있는 전기 발광 소자를 Langmuir-Blodgett(LB)법을 이용하여 제작하였다. 사용 시료는 본 연구팀에서 합성을 하였으며, 시료는 PECCP[poly(3,6-N-2-ethylhexyl carbazolyl cyanoterephthalidene)]이며, 이 물질은 반복되는 주쇄에서 강한 전자 주게 그룹과 강한 전자 받게 그룹을 가지고 있다. PECCP 발광층을 제작하는데는 Langmuir-Blodgett(LB)법을 사용하였으며, 누적 층수에 의해 금속/고분자 계면의 특성을 조사하였다. 소자의 구조는 ITO/PECCP LB/Al과 ITO/PECCP LB/$Alq_3$/Al이며, ITO와 $Alq_3$ 사이에 발광층으로써 PECCP LB막을 도입하였다. 여기서 $Alq_3$는 전자 전달 층으로 사용되었다. PECCP LB막의 UV/visible 흡수 피크는 약 410mm에서, PL 피크는 약 536mm에서, 그리고 EL 피크도 역시 약 536nm에서 관찰되었다. 또한 $Alq_3$를 도입한 구조에서의 EL 피크 측정 결과 다양한 발광피크가 관측되었으며, Fowler-Nordheim 분석법을 이용하여 금속의 유기 막에 대한 일함수 값을 계산하였으며, 금속의 유기 막에 대한 일함수 값은 $0.18{\sim}0.26eV$이 계산되었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.831-834
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• 2000

Characteristics of organic light-emitting diodes(OLEDs) were studied with devices made by PECCP[poly(3,6-N-2-ethylhexyl carbazolyl cyanoterephthalidene)] Langmuir-Blodget(LB) films. The emissive organic material was synthesized and named PECCP, which has a strong electron donor group and an electron accepter group in main chain repeated unit. The LB technique was employed to investigate the identification of the recombination zone in the ITO/PECCP LB films/Alq$_3$/Al structure by varying the LB film thickness. PECCP was considered as an emissive layer and Alq$_3$was used as an electron-transport layer. We measured current-voltage(I-V) characteristics, UV/visible absorption, PL spectrum, and EL spectrum of those devises.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.143-146
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• 1999

In this study, Ultra-thin films of (N-ducosyl quinolinium)-TCNQ(1:2) complex were prepared on the hydrophilic substrate by Langmuir-Blodgett(LB) technique. By measure of UV-vis spectra and capacitance, deposition status was confirmed together with the thickness of natural oxidized aluminum film inside a device and dielectric constant of (N-docosyl quinolinium)-TCNQ(1:2) complex. The electrical properties of (N-docosyl 7uin7linium)-TCNQ(1:2) complex were investigated at room temperature. The conductivity of this film measured by the direction uf either vertical or horizontal axis is results in a quite different value.

• Journal of the Korean Applied Science and Technology
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• v.22 no.4
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• pp.315-322
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• 2005

We investigated the electrochemical properties for Langmuir-Blodgett (LB) films mixed with 4-octyl-4'-(5-carboxylpentamethyleneoxy)azobenzene (denoted as 8A5H) and $phospholipid(L-{\alpha}-dimyristoylphosphatidylcholine$, denoted as DMPC). LB films of 8A5H monolayer and 8A5H-DMPC were deposited by using the Langmuir-Blodgett method on the indium tin oxide(ITO) glass. The electrochemical properties measured by using cyclic voltammetry with a three_electrode system, an Ag/AgCl reference electrode, a platinum wire counter electrode and LB film-coated ITO working electrode at various concentrations(0.1, 0.5, and 1.0mol/L) of $NaClO_4$ solution. A measuring range was reduced from initial potential to -1350mV, continuously oxidized to 1650mV and measured to the initial point. The scan rates were 50, 100, 150 and 200mV/s, respectively. As a result, LB films of 8A5H monolayer appeared irreversible process caused by only the oxidation current from the cyclic voltammogram and LB films of 8A5H-DMPC mixture were found to be caused by a reversible oxidation-reduction process.