• Title/Summary/Keyword: electrodes thickness

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Effects of the Thickness and Dopant on the Photoelectro- chemical Conversion in the Polycrystalline $TiO_2$ Electrodes (광전기 화학변환에 미치는 $TiO_2$ 전극의 두께와 첨가제의 영향)

  • 윤기현;강동헌
    • Journal of the Korean Ceramic Society
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    • v.21 no.3
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    • pp.266-270
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    • 1984
  • The photoelectrochemical properties of the reduced $TiO_2$ceramic electrodes are investigated varying the thickness of the electrodes and the amounts of $Sb_2O_3$ as dopant. As the thickness of the undoped. $TiO_2$ceramic electrode increases the photocurrent tends to decrease. However for the R-F sputtered $TiO_2$ thin film electrodes the photocurrent tends to increase to about 1$\mu\textrm{m}$ thick and then decreases with increasing thickness. For the $TiO_2$ ceramic electrodes doped with $Sb_2O_3$ the photocurrent decreases with inreasing the amounts of dopant and in the case of rapid cooling in air without reduction treatment the photocurrent shows lower value. Also visible light excitation is observed at 500~550(nm) wavelength for the $TiO_2$ ceramic electrodes doped with $Sb_2O_3$comparing wtih the $TiO_2$ ceramic electrodes (~420nm)

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Understanding the Effect on Hydrogen Evolution Reaction in Alkaline Medium of Thickness of Physical Vapor Deposited Al-Ni Electrodes (Physical Vapor Deposition 방법으로 제조된 Al-Ni 전극의 두께가 알칼라인 수전해 수소발생반응에 미치는 영향 연구)

  • HAN, WON-BI;CHO, HYUN-SEOK;CHO, WON-CHUL;KIM, CHANG-HEE
    • Journal of Hydrogen and New Energy
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    • v.28 no.6
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    • pp.610-617
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    • 2017
  • This paper presents a study of the effect of thickness of porous Al-Ni electrodes, on the Hydrogen Evolution Reaction (HER) in alkaline media. As varying deposition time at 300 W DC sputtering power, the thickness of the Al-Ni electrodes was controlled from 1 to $20{\mu}m$. The heat treatment was carried out in $610^{\circ}C$, followed by selective leaching of the Al-rich phase. XRD studies confirmed the presence of $Al_3Ni_2$ intermetallic compounds after the heat treatment, indicating the diffusion of Ni from the Ni-rich phase to Al-rich phase. The porous structure of the Al-Ni electrodes after the selective leaching of Al was also confirmed in SEM-EDS analysis. The double layer capacitance ($C_{dl}$) and roughness factor ($R_f$) of the electrodes were increased for the thicker Al-Ni electrodes. As opposed to the general results in above, there were no further improvements of the HER activity in the case of the electrode thickness above $10{\mu}m$. This result may indicate that the $R_f$ is not the primary factor for the HER activity in alkaline media.

ESTIMATION OF LOCAL LIQUID FILM THICKNESS IN TWO-PHASE ANNULAR FLOW

  • Lee, Bo-An;Yun, Byong-Jo;Kim, Kyung-Youn;Kim, Sin
    • Nuclear Engineering and Technology
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    • v.44 no.1
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    • pp.71-78
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    • 2012
  • In many semi-empirical analyses of flow boiling heat transfer, an annular flow is often assumed as a model flow and the local liquid film thickness is a key parameter in the analysis. This work considers a simple electrical conductance technique to estimate the local liquid film thickness in two-phase annular flows. In this approach, many electrodes are mounted flush with the inner wall of the pipe. Voltage differences between two neighboring electrodes for concentric annular flows with various liquid film thicknesses are obtained before the main experiments and logged in a look-up table. For an actual application in the annual flow, voltage differences of neighboring electrodes are measured and then corresponding local film thicknesses are determined by the interpolation of the look-up table. Even though the proposed technique is quite simple and straightforward, the numerical and static phantom experiments support its usefulness.

Operating Voltage of Optical Instruments based on Polymer-dispersed Liquid Crystal for Inspecting Transparent Electrodes

  • Yeo, Sunggu;Oh, Yonghwan;Lee, Ji-Hoon
    • Current Optics and Photonics
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    • v.1 no.1
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    • pp.45-50
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    • 2017
  • Optical instruments based on polymer-dispersed liquid crystal (PDLC) have been used to inspect transparent electrodes. Generally the operating voltage of an inspection instrument using PDLC is very high, over 300 V, reducing its lifetime and reliability. The operating-voltage issue becomes more serious in the inspection of touch-screen panel (TSP) electrodes, due to the bezel structure protruding over the electrodes. We have theoretically calculated the parameters affecting the operating voltage as a function of the distance between the TSP and the PDLC, the thickness, and the dielectric constant of the sublayers when the inspection module was away from the TSP electrodes. We have experimentally verified the results, and have proposed a way to reduce the operating voltage by substituting a plastic substrate film with a hard coating layer of smaller thickness and higher dielectric constant.

Effects of Dielectric Layer Thickness and Electrode Structures on High Xe AC-PDP (High Xe AC PDP에서 전극구조와 유전체 두께에 따른 방전 특성 분석)

  • Heo, Jun;Kim, Yun-Gi;Kim, Dong-Hyun;Lee, Hea-June;Lee, Ho-Jun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.2
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    • pp.237-242
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    • 2012
  • In this paper, we investigated effects of ITO electrode geometry and dielectric layer thickness on the discharge Characteristic of AC PDP. As the dielectric thickness is decreased ($30{\sim}12{\mu}m$), firing and sustain voltage is decreased. Luminance and discharge power increase with decreasing dielectric layer thickness because of increasing capacitance between plasma and electrodes. Reactive power decreases with dielectric thickness due to reduced capacitance between sustain electrodes. For the high Xe test panel with small ITO electrode, luminous efficacy as well as luminance increase with decreasing dielectric layer thickness. This result suggest that high power density and small plasma volume is beneficial for high efficacy discharge.

Study on die electric characteristics of TIPS-pentacene transistors with variation of electrode thickness (소스/드레인 전극의 두께변화에 따른 TIPS-pentacene 트랜지스터의 전기적 특성 연구)

  • Yang, Jin-Woo;Hyung, Gun-Woo;Kim, Young-Kwan
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.323-324
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    • 2009
  • We investigated the electrical properties of tris-isopropylsilylethynyl (TIPS)-pentacene organic thin-film transistors (OTFTs) employing Ni/Ag source/drain electrodes. The gap height between the gate insulator and S/D electrode was controlled by changing the thickness of Ag under-layer(20, 30, 40 and 50nm). After evaporating the Ni under-layer, TIPS pentacene channel material was dropping the gap between the gate insulator and SID electrodes. The electrical proprieties of OTFT such as filed-effect mobility, on/off ratio, threshold voltage and subthreshold slope were significantly influenced by the gap height.

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A Study on Phase-Matching of Electrodes for Traveling-Wave Electrooptic Integrated Devices (진행파형 전기광학 집적소자에 대한 전극의 위상정합에 관한 연구)

  • 정홍식;이두복;정영식
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.29A no.8
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    • pp.41-48
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    • 1992
  • The characteristics of traveling-wave electrodes for high-frequency electroptic integrated devices are described from the view point of improvement of phase-matching based on the conformal mapping method. Specific calculations of the characteristic impedance, effective microwave index, and eletrode loss for asymmetric coplanar strip(ACPS) and coplanar waveguide(CPW) electrode structures are presented as a function of the geometric electrode parameters including the electrode thickness and buffer layer thickness. 5-10(x10S0-6Tm) thick Au-ACPS electrodes were successfully fabricated by electroplating and ECR etcher. The improvement of modulation bandwidth can be theoretically observed from the combination of electrode and buffer layer thickness.

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The Analysis on the Deformation of Electrostrictive Polymer Film with respect to Time under Constant Voltage

  • Park, Kyung-Chul;Yun, Ji-Won;Jeon, Jae-Wook;Park, Hyoukryueol;Kim, Hunmo;Nam, Jae-Do
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.46.5-46
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    • 2001
  • Electrostrictive polymer is deformed by electric force generated by electric field built by high voltage. When high voltage is applied to the electrostrictive polymer film in which the electrodes such as conductive grease or carbon powder are installed, it expands in the direction of area. Because electrostrictive polymer is incompressible and electric force is applied to it in the direction of thickness. Electrostrictive polymer film in which electrodes are installed, functions as a parallel-plate capacitor. Therefore anode and cathode charges are piled up or both electrodes and there exists attractive force that functions as pressure in the direction of thickness. So the thickness of electrostrictive polymer becomes thicker ...

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Electro-Optic Characteristics of the Fringe Field Switching (FFS) Mode Depending on Thickness of Passivation Layer between Pixel and Common Electrodes (FFS 모드의 공통전극과 화소전극 사이의 절연층 두께에 따른 전기광학 특성)

  • Jung, Jun-Ho;Ha, Kyung-Su;Lim, Young-Jin;Yoo, Il-Sou;Jeong, Yeon-Hak;Lyu, Jae-Jin;Kim, Kyeong-Hyeon;Lee, Seung-Hee
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.22 no.7
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    • pp.589-594
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    • 2009
  • We have studied electro-optic characteristics as a function of passivation thickness existing between common electrode and pixel electrodes in the fringe-field switching (FFS) mode using the LC with positive dielectric anisotropy. A steep increase in the transmission is observed with increase in the passivation layer from $0.29{\mu}m$ to $1.09{\mu}m$ and thereafter it almost saturates over the $1.09{\mu}m$ of passivation layer. This saturation is mainly associated with correlation between transmittance at the center region of pixel electrode and at the center region between pixel electrodes. From the results, optimal thickness of passivation layer can be defined.

A Study on the TCO-less Dye-Sensitized Solar Cell Fabricated with Using Conductive Sputtering Carbon Electrodes (전도성 스퍼터링 탄소전극을 사용한 TCO-less 염료감응형 태양전지의 특성에 관한 연구)

  • Joo, Yong Hwan;Kim, Nam-Hoon;Park, Yong Seob
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.29 no.11
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    • pp.725-728
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    • 2016
  • We investigated the characterizations of carbon films fabricated by dual magnetron sputtering under various film thickness for the electrodes in TCO-less DSSC (dye-sensitized solar cells). Carbon films prepared at various conditions were exhibited smooth and uniform surfaces without defects. Also, the rms surface roughness of carbon films was decreased from 2.25 nm to 1.0 nm with the increase of film thickness. The sheet resistance as the electrical properties are improved from $11.2{\times}10^{-3}$ to $2.28{\times}10^{-3}$ with the increase of film thickness. In the results, the performance of TCO-less DSSC critically depended on the film thickness of working electrodes, indicating the conductivity of carbon films.