• Journal of Integrative Natural Science
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• v.4 no.4
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• pp.294-297
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• 2011

Quality of PEDOT electrode thin film vapor phase-polymerized on 3-aminopropyltriethoxysilane (APS) self-assembled monolayer (SAM) is very crucial for making an ohmic contact between electrode and semiconductor layer of an organic transistor. In order to improve the quality of PEDOT film, the quality of APS-SAM laying underneath the film must be in the best condition. In this study, in order to improve the quality of APS-SAM, the monolayer was self-assembled on $SiO_2$ surface by a dip-coating method under strictly controlled relative humidity (< 18%RH). The quality of APS-SAM and PEDOT thin film were investigated with a contact angle analyzer, AFM, FE-SEM, and four-point probe. The investigation showed that a PEDOT film grown on the humidity-controlled SAM is very smooth and compact (sheet resistivity = 20.2 Ohm/sq) while a film grown under the uncontrolled condition is nearly amorphous and contains quite many pores (sheet resistivity = 200 Ohm/sq). Therefore, this study clearly proves that a highly improved quality of APSSAM can offer a highly conductive PEDOT electrode thin film on it.

• Elastomers and Composites
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• v.43 no.4
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• pp.264-270
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• 2008

$\alpha$-D-mannosyl fullerene[$C_{60}$]-functionalized gold nanoparticle films were selfassembled using the layer-by-layer method on the reactive of glass slides functionlized with 3-aminopropyltrimethoxysilane. The functionalized glass slides were alternately soaked in the solutions containing $\alpha$-D-mannosyl fullerene[$C_{60}$] and 4-aminothiophenoxide/hexanethiolate-protected gold nanoparticles. $\alpha$-D-mannosyl fullerene[$C_{60}$]-functionalized gold nanoparticle films have grown up to 5 layers depending on the immersion time. The self-assembled nanoparticle films were characterized using UV-vis spectroscopy showed that the surface plasmon band of gold at 530 nm gradually became more evident as successive layers were added to the films.

• Journal of the Korean Electrochemical Society
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• v.5 no.3
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• pp.143-152
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• 2002

The growth of Polypyrrole film has been investigated during electropolymerization in an aqueous solution on bare and SAM modified gold electrodes by in-situ EQCM and ex-situ AFM. According to the result of cyclic voltammetry measurements, in the case of a bare gold electrode, the electrochemical deposition of polypyrrole were dependent on the limiting oxidative potential, but not on scan numbers. When the limiting potential higher than 0.8 V was applied on the electrode, the amount of polypyrrole deposited on a gold electrode was rapidly increased and the abnormal mass change attributed to the rearrangement of polypyrrole films was observed as the scan number increased. The polypyrrole film Prepared on electrodes modified with 1-dodecanethiol SAM or thiophene SAM grew 3-dimensionally with the rearrangement of film. However, in the case of BPUS SAM, 2-dimensional layer-by-layer growth of film was observed without the rearrangement of film. AFM images showed films with chain-shaped and/ or donut-shaped polymers when grown rapidly and a wrinkled film at the steady state condition.

• Korean Journal of Materials Research
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• v.20 no.5
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• pp.235-240
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• 2010

We investigated the carbon monoxide (CO) gas-sensing properties of nanostructured Al-doped zinc oxide thin films deposited on self-assembled Au nanodots (ZnO/Au thin films). The Al-doped ZnO thin film was deposited onto the structure by rf sputtering, resulting in a gas-sensing element comprising a ZnO-based active layer with an embedded Pt/Ti electrode covered by the self-assembled Au nanodots. Prior to the growth of the active ZnO layer, the Au nanodots were formed via annealing a thin Au layer with a thickness of 2 nm at a moderate temperature of $500^{\circ}C$. It was found that the ZnO/Au nanostructured thin film gas sensors showed a high maximum sensitivity to CO gas at $250^{\circ}C$ and a low CO detection limit of 5 ppm in dry air. Furthermore, the ZnO/Au thin film CO gas sensors exhibited fast response and recovery behaviors. The observed excellent CO gas-sensing properties of the nanostructured ZnO/Au thin films can be ascribed to the Au nanodots, acting as both a nucleation layer for the formation of the ZnO nanostructure and a catalyst in the CO surface reaction. These results suggest that the ZnO thin films deposited on self-assembled Au nanodots are promising for practical high-performance CO gas sensors.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.2
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• pp.109-115
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• 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.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1021-1024
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• 2003

In this work, we fabricated various 2D metallic and polymeric nanopatterns with the feature resolution of sub-micrometer scale by using the method of microcontact printing ($\mu$ P) based on soft lithography. Silicon masters for the micromolding were made by e-beam lithography. Composite poly(dimethylsiloxane) (PDMS) molds were composed of a thin, hard layer supported by soft PDMS layer. Finally, monodisperse metal or polymer particles could be obtained in the prepared pattern for the application of electronic devices.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.6
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• pp.527-531
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• 2005

Fully coherent self-assembled InAs quantum dots(QDs) grown on Si (100) substrates by atmospheric pressure metalorganic chemical vapor deposition(APMOCVD) were grown and the effect of growth conditions such as growth rate and growth time on quantum dots' morphology such as densities and sizes was investigated. InAs QDs of 30 - 80 nm in diameters with densities in the range of (0.6 - 1.7) x $10^{10}\;cm^{-2}$ were achieved on Si substrates and InAs layer was changed from 2 dimensional growth to 3 dimensional one at a nominal thickness less than 0.48 ML. This is attributed to the higher ambient pressure of APMOCVD suppressing of In segregation from the 2 dimensional InAs layer. This In segregation looked to disturb the dot formation especially when the growth rate was low so that the dots became less dense and bigger as the growth rate was lower.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.523-524
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• 2010

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.3
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• pp.115-118
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• 2005

Currently, molecular devices are reported utilizing active self-assembled monolayers (SAMs) containing the nitro group as the active component, which has active redox centers [1]. SAMs are ordered molecular structures formed by the adsorption of an active surfactant on a solid surface. The molecules will be spontaneously oriented toward the substrate surface and form an energetically favorable ordered layer. During this process, the surface-active head group of the molecule chemically reacts with and chemisorbs onto the substrate In this paper, the electrical properties of the 4'4- di(ethynylphenyl)-2'-nitro-1-benzenethiolate was confirmed. This material is well known as a conducting molecule having possible application to molecular level negative differential resistance (NDR) device. To deposit the self-assembly monolayers onto the gold electrode, the prefabricated Au(1 l l) substrates were immersed into 0.5[mM/l] self-assembly molecule in THF solution. Then, the electrical properties and surface morphologies of 4' 4-di(ethynylphenyl)-2' -nitro-1-benzenethiolate were measured by using the ultra-high vacuum scanning tunneling microscopy (UHV-STM).

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.500-501
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• 2005