• 한국초전도학회:학술대회논문집
• /
• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
• /
• pp.252-256
• /
• 2000

We investigated resistance development in Au/YBCO thin film meander lines during quench. The meander lines were fabricated by coating YBCO films insitu with a gold layer and patterning them by photolithography. The center stripe quenched fastest even though the flux flow resistance that appeared upon the current passing the critical current was uniform. Quench started at an area of the center stripe and propagate both through the gold layer and the sapphire substrate. Quench propagation speed was uniform and 60 cm/s at 30 V$_{rms}$.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 디스플레이 광소자분야
• /
• pp.119-122
• /
• 2003

We report a dramatic increase in the photo-stability of a blue-emitting polymer, poly(9,9-dioctylfluorene), achieved by the addition of gold nanoparticles to the polymer. The optical absorption band of gold nanoparticles is tuned to resonate the triplet exciton-ground state band gap energy of the polymer. The photo-oxidation rate of poly(9,9-dioctylfluorene) was drastically reduced by doping the polymer with a very small amount ($10^{-6}-10^{-5}$ volume fraction) of gold nanoparticles. The gold nanoparticles used herein act as the quenching agent of the triplet states and can be directly applied to various blue light emitting polymer thin film ( < 100 nm ) devices.

• 한국세라믹학회지
• /
• 제30권9호
• /
• pp.695-700
• /
• 1993

In this study, we prepared Pb-Ti stock solution by sol-gel processing and deposited PbTiO3 thin film on a Pt coated SiO2/Si wafer by spin coating using the stock solution. We used lead acetate trihydrate and titanium isopropoxide. The stock solution was partially hydrolized and finally a 0.25M coating solution was prepared. We achieved spin coating at 4000rpm for 30 seconds and heated the thin film at 375$^{\circ}C$ for 5 minutes and at $600^{\circ}C$ for 5 minutes successively, first and second heating state. And the thin film was finally sintered at 90$0^{\circ}C$ for 1 hour in the air. The upper electrode of the thin film was made by gold sputtering and was cricle shape with radius 0.4mm. Measured dielectric constant, dissipation factor and phase transition temperature(Cuire Temp.) were about 275, 0.02 and 521$^{\circ}C$ respectively. To observe ferroelectric characteristics we calculated Pr(remnant polarization) and Ec(coercive field) byhysteresis curve. Ec was 72kV/cm and Pr was 11.46$\mu$C/$\textrm{cm}^2$.

• 센서학회지
• /
• 제7권4호
• /
• pp.279-284
• /
• 1998

수용액에서 자당의 농도 변화를 감지하기 위한 센서개발을 목적으로 하여, 금박막을 센서칩으로 사용한 SPR(surface plasmon resonance) 센서시스템을 구성하였다. 센서칩 제작시 금박막의 특성조건은 SPR 현상에 매우 큰 영향을 미치므로, 센서 제작의 최적화를 위해 특성을 분석하여 두께 약 $545\;{\AA}$, 표면 평균 거칠기 약 $3\;{\AA}$이 되도록 균일하게 제작하였다. 이렇게 제작된 금박막 센서칩의 공명각은 $43.75^{\circ}$ 이었으며, $0{\sim}40\;wt%$ 농도의 자당 수용액을 측정한 결과 기존의 알려진 자당 센서에 비해 빠른 응답특성과 선형적인 공명특성을 얻을 수 있었다.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
• /
• pp.354.1-354.1
• /
• 2016

Nanoporous gold (NPG) is a very promising material in various fields such as sensor, actuator, and catalysis because of its high surface to volume ratio and conducting nature. In this study, we fabricated a NPG based amperometric sensor on a glass substrate by means of co-sputtering of Au and Si. During the sputtering process, we found the optimum conditions for heat treatment to reduce the residual stress and to improve adhesion between NPG films and the glass substrate. Subsequently, Si was selectively etched from Au-Si alloy by KOH solution, which forms nanoporous structures. Scanning electron microscopy (SEM) and auger electron spectroscopy (AES) were used to estimate the structure of NPG films and their composition. By employing appropriate heat treatments, we could make very stable NPG films. We tested the performance of NPG sensor with aniline molecules, which shows high sensitivity for sensing low concentration of aniline.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2009년도 하계학술대회 논문집
• /
• pp.49-49
• /
• 2009

Nanocomposites of gold nanoparticles and multi-walled carbon nanotubes (MWNTs) were prepared by electrostatic interaction. Gold nanopartic1es were stabilized by polyvinylpyrrolidone (PVP), sodium dodecyl sulfate (SDS) and poly(sodium-4-styrenesulfonate) (PSS) in aqueous medium, and MWNTs were modified by poly(diallyldimethylammonium)chloride (PDDA) in water. The as-perpared Au-MWNT nanocomposites were structurally and electrically characterized by transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), UV/Vis spectroscopy, X-ray photoelectron spectroscopy (XPS) and cyclo voltammetry (CV). UV/Vis spectra of Au-MWNT nanocomposites showed the characteristic surface plasmon bands in the range of ~515nm, depending on the stabilizers. There is only slight change on the band shape with variation of stabilizing agents for gold nanoparticles. Through FE-SEM and TEM images, the distribution of gold, nanoparticles on the sidewalls of MWNTs was deliberately investigated on Au-MWNT nanocomposites treated with different stabilizers. XPS and CV showed redistribution of electron densities and changes in the binding energy states of nanopartic1es in nanocomposite respectively.

• 한국진공학회지
• /
• 제13권1호
• /
• pp.9-13
• /
• 2004

본 연구에서는 P 형과 N 형의 특성을 모두 갖추 것으로 알려진 perylene의 특성을 연구하였다. 특히 구조적 특성과 전기적 특성 향상을 위하여 초고진공 상태에서 $SiO_2$ 기판 위에 perylene 박막을 제작하였는데 증착 속도에 따른 박막의 특성 향상 여부를 살펴보기 위하여 0.1 $\AA$/s 와 1 $\AA$/s로 변화시켜가며 박막을 제작하였다. 박막의 결정성과 표면 특성은 X-선 회절과 원자 간력 현미경을 이용하여 살펴보았는데, 1 $\AA$/s로 증착된 perylene박막이 더 우수한 결정성과 표면 분포를 보였다. 박막의 전기적 특성 확인을 위하여 heavily doped 실리콘 기판 위에 $SiO_2$와 gold를 이용한 perylene 박막 트랜지스터를 제작하였다. 얻어진 perylene 박막 트랜지스터는 P 형의 반도체적 성질을 나타내었으며, 전류-전압 특성 곡선을 이용하여 $2.23\times10^{-5}\textrm{cm}^2$/Vs 의 전하 이동도를 얻었다.

• 한국전기전자재료학회논문지
• /
• 제28권7호
• /
• pp.433-438
• /
• 2015

Zinc tin oxide transparent thin film transistors (ZTO TTFTs) were fabricated by using $n^+$ Si wafers as gate electrodes. Indium (In), aluminum (Al), indium tin oxide (ITO), silver (Ag), and gold (Au) were employed for source and drain electrodes, and the mobility and the threshold voltage of ZTO TTFTs were observed as a function of electrode. The ZTO TTFTs adopting In as electrodes showed the highest mobility and the lowest threshold voltage. It was shown that Ag and Au are not suitable for the electrodes of ZTO TTFTs. As the results of this study, it is considered that the interface properties of electrode/ZTO are more influential in the properties of ZTO TTFTs than the conductivity of electrode.

• 설비공학논문집
• /
• 제11권4호
• /
• pp.528-536
• /
• 1999

This work studies the effects of transient reflectance on the thermal responses of a metal(gold) thin-film during ultrashort laser heating. The heating process is calculated using the conventional conduction model (parabolic one-step: POS), parabolic two-step model (PTS) with and without variable properties, hyperbolic two-step model (HTS). Results from the HTS model are very similar to those from the PTS model, since the laser heating time in this study is greater than the electron relaxation time. PTS model with variable properties, however, results in totally different temperature profiles compared to those from POS models or calculation with constant properties. Transient reflectances are estimated from electron temperature distributions and based on the linear relationship between the electron temperature and complex dielectric constants. Reflectance of the front surface can be changed with respect to dielectric constants, while those of the rear surface remain unchanged.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
• /
• pp.271-272
• /
• 2008

We fabricated a pentacene thin-film transistor with Ni/Ag source/drain electrodes. Also, we obtained similar electrical characteristics as compared with source/drain electrode with Au. This device was found to have a field-effect mobility of about 0.021 $cm^2$/Vs, a threshold voltage of -5, -7 V, an subthreshold slope of 2.0, 4.5 V/decade, and an on!off current ratio of $3.6\times10^5$, $2.0\times10^6$.