• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1998년도 추계학술대회 논문집
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• pp.97.1-100
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• 1998

We studied on the ultra thin L- $\alpha$ -DLPC by LB method. The $\pi$ -A isotherm of the L- e -DLPC was measured at the air-water interface varying with the compressing speed and amounts of solutions for spreading. The molecular arrangement of deposited films were evaluated by measuring the absorption with the UV spectrometer. And we made structures of metal(Au)/L- $\alpha$ -DLPC/Metal(Au) and examined electron through L- $\alpha$ -DLPC LB films by means of current-voltage(I- V) measurement

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.601-604
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• 1999

Electroluminescence(EL) devices based on organic thin films have attracted lots of interests in large-area light-emitting display. Recently, many EL researcher have interested a new emissive organic material. In this study, light-emitting organic electroluminescent devices were fabricated using Langmuir-Blodgett(LB) technique with new emissive organic material. This new emissive organic material were synthesis by our teams and we called PECCP [poly(3,6-N-2ethylhexyl carbazoly cyanoterephthalidene)] which has strong electron donor group and electron acceptor group in main chain repeat unit. This material has good solubility in common organic solvent such as chloroform. THF, etc. and has a good stability in air. In here, the new emissive material is applied to Langmuir-Blodgett(LB) method because our new material has a good stability in air. Optimum conditions of film deposition were examined by a surface pressure-area( $\pi$ -A) isotherms with various factors. The LB film were deposited on a indium Tin Oxide(ITO) glass. We were investigated by measuring current-voltage(I-V) characteristics. Also we were measured the UV/visible absorption at about 410nm and PL spectrum at about 530nm. We are attempt to the electroluminescence device properties of the new emissive material by Langmuir-Blodgett(LB) technique.

• 한국응용과학기술학회지
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• 제31권3호
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• pp.352-358
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• 2014

포화지방산(C12, C14, C16, C18) 단분자층 LB막의 전기화학적 특성을 통하여 그 안정성을 순환전압전류법으로 조사하였다. 포화지방산 단분자층 LB막은 ITO glass에 LB법을 사용하여 제막하였다. 전기화학적 특성은 0.1 N $NaClO_4$ 용액에서 3 전극 시스템으로 순환전압전류법에 의해 측정하였다. 측정범위는 연속적으로 1650 mV로 산화시키고, 초기 전위인 -1350 mV로 환원시켰다. 주사속도는 각각 50, 100, 150, 200 및 250 mV/s로 설정하였다. 그 결과 포화지방산 LB막은 순환전압전류곡선으로부터 산화전류로 인한 비가역공정으로 나타났다. 포화지방산 LB막의 확산계수(D)를 산출한 결과 각각 라우르산, $2.223{\times}10^{-3}cm^2/s$, 미리스트산, $2.461{\times}10^{-4}cm^2/s$, 팔미트산, $7.114{\times}10^{-4}cm^2/s$ 및 스테아르산, $2.371{\times}10^{-4}$을 얻었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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• pp.128-130
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• 2001

In this study, we investigate the deposition characteristics of merocyanine dye(MD) Langmuir-Blodgett(LB) film using quartz crystal microbalance (QCM). The MD optical system mixed with fatty acid was fabricated using LB method. And their optical characteristics were investigated using UV spectroscopy. The optical behavior of MD LB film was investigated asto thermal treatment. The resonant frequency and admittance was measured during dissociation of J-aggregate of MD LB film. As a result, it has been suggested that the J-aggregate dissociation in MD LB film by thermal treatment give rise to transformation of oscillation characteristics of quartz crystal.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.167-170
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• 1998

The electrical characteristics of Stearic acid LB films were investigated to develop the gas sensor using Langmuir-Blodgett(LB) films. The deposition status of LB films were verified by the measurements of UV absorbance and I-V characteristics. The conductivity of Stearic acid LB films at room temperature was $10^{-8}[S/cm]$, which is typical of semiconductor. The conductivity was found to increase as the temperature was increased. The acitivation energy was about 1[eV].

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 추계학술대회 논문집
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• pp.277-280
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• 1995

We had experiment using LB method that can fabricate molecular order ultra-thin film below 100${\AA}$. LB mettled has known as main technology of information society in 21C, because it is nut only free oriention and alignment of molecular but also ability of thickness control as molecular order. In this paper, the fabricated condition and physical properities of functional ultra-thin film of molecular order was investigated and highly efficient ultra-thin film capacitor was fabricated by using ultra-thin LB film for application as electronic device. Possibility of ultra-thin film capacitor was researched by analizing rind measuring electrical properties. Polyimide ultra-thin LB film capacitor was fabricated, ensured theoretically rind experimentally its possibility in range of 10Hz∼ 1MHz through its frequency characteristics.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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• pp.202-205
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• 1997

In this paper, we synthesized poly(N-(2-4-imidazolyl) ethyl) maleimide-alt-1-octadecene(IMI-O) polymer that can have function group and improvement of mechnical strength and then confirmed the possibility of molecular device made by LB method. Evaluation of LB film have been processed such as the technique of EA, $^{1}$H-NMR, FT-IR. Also, the deposition status was observed by SEM and Metal/Insulator/Metal(MIM) device was fabricated for investigation of electric properties. In our experimental results. The surface pressure for the solid state was investigated to 20~35[dyne/cm] by the $\pi$ -A isotherm and the limiting area was about 40 ~45 ($\AA$$^2$/molecule). The deposition status of LB films was confirmed by SEM. The conductivity of LB film was found to be 10$^{-14}$ ~10$^{-13}$ [S/cm] by I-V characteristic.

• 센서학회지
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• 제31권4호
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• pp.249-254
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• 2022

To achieve high-performance colloidal quantum dot light-emitting diodes (QD-LEDs), the use of a densely packed QD film is crucial to prevent the formation of leakage current pathways and increase in interface resistance. Spin coating is the most common method to deposit QDs; however, this method often produces pinholes that can act as short-circuit paths within devices. Since state-of-the-art QD-LEDs typically employ mono- or bi-layer QDs as an emissive layer because of their low conductivities, the use of a densely packed and pinhole-free QD film is essential. Herein, we introduce the Langmuir-Blodgett (LB) technique as a deposition method for the fabricate densely packed QD films in QD-LEDs. The LB technique successfully transfers a highly dense monolayer of QDs onto the substrate, and multilayer deposition is performed by repeating the transfer process. To validate the comparability of the LB technique with the standard QD-LED fabrication process, we fabricate and compare the performance of LB-based QD-LEDs to that of the spin-coating-based device. Owing to the non-destructiveness of the LB technique, the electroluminescence efficiency of the LB-based QD-LEDs is similar to that of the standard spin coating-based device. Thus, the LB technique is promising for use in optoelectronic applications.

• 의학교육논단
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• 제23권1호
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• pp.3-10
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• 2021

Learning by teaching (LbT) has long been recognized as an important learning behavior that constructs meaning based on interactions between learners. This study aimed to explore the meaning of LbT as an important learning activity for future implementation in education. LbT is based on the cultural historical activity theory and sociocultural learning theory, as developed by scholars including Vygotsky. These frameworks value the construction of meaning based on language, and LbT is reported to be effective in constructing meaning. In addition, within the zone of proximal development posited by Vygotsky, learning through interaction between learners improves academic achievement, higher-order thinking, deep learning, and reflective learning. LbT also promotes students' learning presence, and strengthens various competencies such as collaboration and communication skills. Interactive behavior between learners in the form of LbT has been explored as an approach to teaching and learning, with methods including peer learning, peer tutoring, peer teaching, peer mentoring, Lernen durch Lehren, and peer-assisted learning. LbT has also been applied as a learning method. In the future, LbT has boundless potential to improve learning through activities such as flipped learning or online learning based on interactions between learners.

• 한국응용과학기술학회지
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• 제30권4호
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• pp.754-760
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• 2013

순환전압전류법에 의한 인지질(sphingomyelin, SP)과 polyamic acid(PAA) 혼합물의 농도(몰비 1:1, 2:1 및 3:1)를 변화시켜 혼합단분자 LB막에 대한 전기화학적 특성을 조사하였다. SP과 PAA 혼합물의 단분자 LB막은 ITO glass에 LB법을 사용하여 제막하였다. 전기화학적 특성은 $KClO_4$ 용액에서 3 전극 시스템으로 측정하였다. 측정 범위는 연속적으로 1650 mV로 산화시키고, 초기 전위인 -1350 mV로 환원시켰다. 주사속도는 각각 50~250 mV/s로 설정하였다. 그 결과 SP와 PAA 혼합물의 LB막은 순환전압전류도표로부터 환원전류로 인한 비가역공정으로 나타났다. 혼합물 LB막의 혼합(SP:PAA) 몰비가 1:1, 2:1 및 3:1에서 확산계수(D)는 각각 $2.670{\times}10^{-5}$, $3.562{\times}10^{-5}$ 및 $1.005{\times}10^{-5}cm^2s^{-1}$을 얻었다.