• Title/Summary/Keyword: Gold thin-film

Search Result 137, Processing Time 0.026 seconds

Resistance development in Au/YBCO thin film meander lines during quench (금/YBCO 박막에서의 quench 저항 발생)

  • Kim, Hye-Rim;Choi, Hyo-Sang;Lim, Hae-Ryong;Kim, In-Seon;Hyun, Ok-Bae
    • 한국초전도학회:학술대회논문집
    • /
    • v.10
    • /
    • 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$_{rms}$.

  • PDF

Light-emitting diodes using gold nanoparticles (금 (gold) 나노 입자를 이용한 고분자 발광소자)

  • Park, Jong-Hyeok;Lim, Yong-Taik;Park, O-Ok;Kim, Jae-Kyeong;Yu, Jae-Woong;Kim, Young-Chul
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2003.04a
    • /
    • 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.

  • PDF

Structural and Dielectric Properties of $PbTiO_3$ Ferroelectric Thin Film Prepared by Sol-Gel Processing (Sol-Gel법으로 제조된 $PbTiO_3$ 강유전 박막의 구조적, 유전적 특성)

  • 김준한;백동수;박창엽
    • Journal of the Korean Ceramic Society
    • /
    • v.30 no.9
    • /
    • 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/$\textrm{cm}^2$.

  • PDF

The Construction of the SPR (Surface Plasmon Resonance) Sucrose Sensor (표면 플라즈몬 공명형 자당 센서의 제작)

  • Um, N.S.;Lee, S.M.;Hahm, S.H.;Koh, K.N.;Lee, S.H.;Kang, S.W.
    • Journal of Sensor Science and Technology
    • /
    • v.7 no.4
    • /
    • pp.279-284
    • /
    • 1998
  • A surface plasmon resonance (SPR) sensor system for the determination of sucrose concentration was constructed with a gold thin film sensing chip. The properties of gold thin film are critical factors in exciting surface plasmon resonance phenomena. Therefore in the present paper, the fabrication conditions of gold thin film were investigated to optimize the SPR phenomena. The optimum thickness was obtained as $545{\AA}$ with $43.75^{\circ}$ resonance angle and good surface roughness limitation. about $3{\AA}$. The linear resonance angle shifts and rapid response were observed from the sucrose concentrations ranged from 0 to 40wt%.

  • PDF

Fabrication of nanoporous gold thin films on glass substrates for amperometric detection of aniline

  • Lee, Keon-U;Kim, Sang Hoon;Shin, Hyung-Joon
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2016.02a
    • /
    • 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.

  • PDF

Characterization of Au-MWNT nanocomposite in thin films (다중벽 탄소나노튜브와 금나노입자를 사용한 나노박막의 특성연구)

  • Kim, Jung-Soo;Bae, Jong-Seong;Ko, Chang-Hyun;Oh, Won-Tea
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2009.06a
    • /
    • 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.

  • PDF

Characteristics of perylene OTFT fabricated in UHV (초고진공환경에서 제작된 perylene 박막 트랜지스터의 특성)

  • 박대식;강성준;김희중;노명근;황정남
    • Journal of the Korean Vacuum Society
    • /
    • v.13 no.1
    • /
    • pp.9-13
    • /
    • 2004
  • Perylene is an interesting material known to have P-type and N-type characteristics at the same time. We prepared perylene thin-films in ultrahigh vacuum with two different deposition rates of 0.1 $\AA$/s and 1.0 $\AA$/s in order to study the dependence of film characteristics on the growth condition. The smaller average grain size with larger surface coverage as well as the better crystallinity were observed on the perylene film prepared under 1.0 $\AA$/s deposition rate in x-ray diffraction (XRD) and atomic force microscopy (AFM) study. For studying electrical property of the film, perylene organic thin-film transistor (OTFT) with gold contacts was fabricated on $SiO_2$/Si surface in UHV condition. The prepared perylene OTFT device shows P-type characteristic. The obtained hole mobility in the current-voltage characteristic curve was$2.23\times10^{-5}\textrm{cm}^2$/Vs.

Influence of Source/Drain Electrodes on the Properties of Zinc Tin Oxide Transparent Thin Film Transistors (Zinc Tin Oxide 투명 박막트랜지스터의 특성에 미치는 소스/드레인 전극의 영향)

  • Ma, Tae Young;Cho, Mu Hee
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.28 no.7
    • /
    • 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.

Effects of transient thermo reflectance on the thermal responses of metal thin film exposed to ultrashort laser heating (극초단 펄스레이저 광이 입사된 금속박막의 열적반응 중 비정상반사율의 영향)

  • 박승호;국정진
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.11 no.4
    • /
    • 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.

  • PDF

Study on Organic Thin-Film Transistors(OTFTs) Devices with Gold and Nickel/Silver electrodes (전극에 따른 유기박막트랜지스터 소자의 전기적 특성 연구)

  • Hwang, Seon-Wook;Hyung, Gun-Woo;Park, Il-Houng;Choi, Hak-Bum;Kim, Young-Kwan
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2008.06a
    • /
    • 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 $3.6\times10^5$, $2.0\times10^6$.

  • PDF