• International Journal of Precision Engineering and Manufacturing
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• v.7 no.3
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• pp.35-38
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• 2006

A study of electrowetting using an Octadecyltrichlorosilane (OTS) self-assembled monolayer (SAM) and Z- Tetraol 2000 perfluoropolyether lubricant as hydrophobic layers on Si and $SiO_2$ wafer was performed. The $SiO_2$ layer used as insulating layer was thermally grown on the silicon wafer to a thickness of 220-230 nm. The results demonstrated that the contact angle decreased from $100^{\circ}$ to $80^{\circ}$ at 28 V applied potential on $SiO_2$ wafer coated with OTS and the contact angle appeared to be reversible. However, the contact angle on the $SiO_2$ wafer coated with Z- Tetraol 2000 was not observable at 28 V applied potential. Furthermore, the contact angle on the Si wafer coated with OTS or Z- Tetraol 2000 appeared to be irreversible due to the generation of electrolysis in the droplet. It is concluded that it is feasible to use SAM as a hydrophobic layer in electrowetting applications.

• Journal of the Korean Applied Science and Technology
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• v.16 no.3
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• pp.193-198
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• 1999

Maxwell displacement current(MDC) measuring technique has been applied on the study of monolayers of fatty acid. 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 $130{\AA}^2$. MDCs were investigated in connection with monolayer compression cycles. It was found that the current pulses were generated over the entire range of molecular area, and the maximum of MDC appeared at the molecular area just before the initial rise of surface pressure in compression cycles. We investigated the change in absorption spectra of the fatty acid(8A5H) monolayer LB film due to cis-trans photoisomerization. It was found that the absorption spectrum of the 8A5H LB film was induce to photoisomerization by alternate irradiation with UV and visible light irradiation.

• 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.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.125-125
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• 2012

Graphene was epitaxially grown on a 6H-SiC(0001) substrate by thermal decomposition of SiC under ultrahigh vacuum conditions. Using scanning tunneling microscopy (STM), we monitored the evolution of the graphene growth as a function of the temperature. We found that the evaporation of Si occurred dominantly from the corner of the step rather than on the terrace. A carbon-rich $(6{\sqrt{3}}{\times}6{\sqrt{3}})R30^{\circ}$ layer, monolayer graphene, and bilayer graphene were identified by measuring the roughness, step height, and atomic structures. Defect structures such as nanotubes and scattering defects on the monolayer graphene are also discussed. Furthermore, we confirmed that the Dirac points (ED) of the monolayer and bilayer graphene were clearly resolved by scanning tunneling spectroscopy (STS).

• Journal of the Korean Electrochemical Society
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• v.2 no.1
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• pp.27-30
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• 1999

Self-Assembled monolayers of carboxyl-terminated alkanethiols, which is negatively charged in pH 7.0, were usually used to facilitate the electron transfer between the positively charged protein and the electrode. In case of L-cysteine, as it has both positive and negative group, it can be a candidate for a new modifier to facilitate positively charged protein or negatively charged protein. Our investigation of L-cysteine shows that the electron transfer occurs successfully to both cytochrome c (cyt. c) and pyrroloquinoline quinone (PQQ). By using 1-ethyl-3-(3-dime-thlyaminopropyl) carbodiimide (EDC), we made a covalent bond between cyt. c and monolayer. Then PQQ was electrostatically adsorbed to the same monolayer. Cyclic voltammograms show that both molecules do not interfere each other and electron transfer is appreciable.

• Journal of the Korean Electrochemical Society
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• v.10 no.1
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• pp.43-47
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• 2007

Electrochemical rectification at electrode chemically modified with redox active agents isolated at monolayer level was considered. Formulation of the rising part of linear sweep voltammogram at steady and rotating disc electrode was introduced.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.221-224
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• 1996

We synthesized amphiphilic material including dye skeleton, p-phenylenediamine(PD) by attaching norma-decyl group of two strands at a part of coordinating atom, for obtaining reasonable design of LB uniform films. The synthesis of this compounds was quantitatively carried out under ultra pure state. This product was identified with FT-lR spectroscopy, UV absortion spectroscopy, and $^1$H-NMR spectroscopy, respectively. When manufacturing monolayer, we confirmed molecular area from pressure-area($\pi$-A) cutie of thiscompound onto the surface of the water. The spectroscopic approach also has done by UV absortion spectroscopy. It was shown that PD-complex LBfilms were deposited well with monolayer thickness. The conductivity based on I-V characteristics of PD-complex LB films were in the range of 10$^{-10}$ S/cm at room temperture. The microscopic properties by AFM, showed the good orientation of various monolayer or multilayer molecules

• Journal of the Korean Ceramic Society
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• v.33 no.9
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• pp.1012-1018
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• 1996

To investigate the final structures and reactions of silicides a somewhat thick Ti monolayer Co monolayer and Co/Ti bilayer films were deposited on single Si(100) wafer by electron beam evaporation followed by heat treatment using RTA system in N2 ambient. TiO2 film formed between Ti and TiSi2 layers due to oxgen or moisture in the Ti monolayer sample. The final layer structure obtained after the silicidation heat-treatment of the Co/Ti bilayer sample turned out to be TiSi2/CoSi2/Ti-Co-Si alloy/CoSi2/Si sbustrate. This implies that imperfect layer inversion occurred due to the formation of Ti-Co-Si intermediate phase.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.858-860
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• 2009

We have applied self-assembled monolayer to make high performance and stable OTFT on the organic gate dielectric. The ${\beta}$-phenethyltrichlorosilane (SAM) was coated on the organic gate dielectric and then active layer was printed. Significant improvements in on-currents and threshold voltage shift were achieved for the SAM treated devices compared to device without SAM.

• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.12-13
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• 2006

The physical properties of DMPC monolayer were made for dielectric relaxation phenomena by the detection of the surface pressures and displacements current. The current was measured after the electric bias 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.