• 제목/요약/키워드: Electrochemical Characterization

검색결과 416건 처리시간 0.029초

Implementation of Electrochemical Methods for Metrology and Analysis of Nano Electronic Structures of Deep Trench DRAM

  • Zeru, Tadios Tesfu;Schroth, Stephan;Kuecher, Peter
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제12권2호
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    • pp.219-229
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    • 2012
  • In the course of feasibility study the necessity of implementing electrochemical methods as an inline metrology technique to characterize semiconductor nano structures for a Deep Trench Dynamic Random Access Memory (DT-DRAM) (e.g. ultra shallow junctions USJ) was discussed. Hereby, the state of the art semiconductor technology on the advantages and disadvantages of the most recently used analytical techniques for characterization of nano electronic devices are mentioned. Various electrochemical methods, their measure relationship and correlations to physical quantities are explained. The most important issue of this paper is to prove the novel usefulness of the electrochemical micro cell in the semiconductor industry.

주조법에 의해 제조된 마그네슘 합금에서 칼슘 첨가가 전기화학적 특성에 미치는 영향 (The Effect of Ca Addition on Electrochemical Properties of Mg-alloy by Casting)

  • Kim, Hye-Sung
    • 한국콘텐츠학회논문지
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    • 제2권1호
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    • pp.120-124
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    • 2002
  • 본 연구에서는 주조법으로 제조한 Mg-Ca 합금의 전기 화학적 특성을 알아보고자 하였다. 연구결과에 의하면 전기화학적 특성이 불순물의 화학조성과 매우 밀접한 관계가 있으며, 칼슘 첨가 전ㆍ후 뚜렷한 미세구조 변화가 있음이 관찰되었다. 본 연구로부터 적은 양의 칼슘이 첨가되면 마그네슘 합금의 미세구조적 변화를 통하여 우수한 전기화학적 특성이 얻어질 수 있음이 확인되었다.

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Effect of Solution-treated on Electrochemical Properties of AZ91 Magnesium Alloy Anode

  • Zhiquan, Huang;Yanjie, Pei;Renyao, Huang;Xiangyu, Gao;Jinchao, Zou;Lianyun, Jiang
    • Journal of Electrochemical Science and Technology
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    • 제13권4호
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    • pp.486-496
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    • 2022
  • The effect of solution-treated on the self-corrosion performance and discharge performance of AZ91 magnesium alloy as anode material was analyzed by microscopic characterization, immersion tests, electrochemical measurements, and discharge performance tests. The study shows that the β-phase in the AZ91 magnesium alloy gradually dissolved in the matrix with the increase of the solution temperature, and the electrochemical activity of the magnesium alloy anode was significantly improved. Through the comparison of three different solution-treated processes, it is found that the AZ91 magnesium alloy has the most vigorous activity and better discharge performance after solution-treated of 415℃+12 h. In addition, the proportion and distribution of β-phase AZ91 magnesium alloy have a direct impact on its discharge performance as an anode material.

Characterization and Electrochemical Performance of Composite BSCF Cathode for Intermediate-temperature Solid Oxide Fuel Cell

  • Kim, Yu-Mi;Kim-Lohsoontorn, Pattaraporn;Bae, Joong-Myeon
    • Journal of Electrochemical Science and Technology
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    • 제2권1호
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    • pp.32-38
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    • 2011
  • The composite barium strontium cobalt ferrite (BSCF) cathodes were investigated in the intermediate temperature range of solid oxide fuel cells (SOFCs). The characteristics and electrochemical performances of composited BSCF/samarium doped ceria (SDC); BSCF/gadolinium doped ceria (GDC); and BSCF/SDC/GDC were compared to single BSCF cathode. The BSCF used in this study were synthesized using glycine nitrate process and mechanically mixing was used to fabricate a composite cathode. Using a composite form, the thermal expansion coefficient (TEC) could be reduced and BSCF/SDC/GDC exhibited the lowest TEC value at $18.95{\times}10^{-6}K^{-1}$. The electrochemical performance from half cells and single cells exhibited nearly the same trend. All the composite cathodes gave higher electrochemical performance than the single BSCF cathode (0.22 $Wcm^{-2}$); however, when two kinds of electrolyte were used (BSCF/SDC/GDC, 0.36$Wcm^{-2}$), the electrochemical performance was lower than when the BSCF/SDC (0.45 $Wcm^{-2}$) or BSCF/GDC (0.45 $Wcm^{-2}$) was applied as cathode ($650^{\circ}C$, 97%$H_2$/3%$H_2O$ to the anode and ambient air to the cathode).

폐수의 악취측정을 위한 금속산화물 반도체 및 전기화학식 가스센서 어레이 특성 평가 (Evaluation of Metal Oxide Semiconductor and Electrochemical Gas Sensor Array Characterization for Measuring Wastewater Odor)

  • 임봉빈;이석준;김선태
    • 센서학회지
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    • 제24권1호
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    • pp.29-34
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    • 2015
  • This study aimed to evaluate the characterization of a metal oxide semiconductor and electrochemical gas sensor array for measuring wastewater odor. The sensitivity of all gas sensors observed in sampling method by stripping was 6.7 to 20.6 times higher than that by no stripping, except sensor D (electrochemical gas sensor). The average reduction ratio of sensor signal as a function of initial dilution rate of wastewater was in the order of food plant > food waste reutilization facility > plating plant. The sensitivity of gas sensors was dependent on both the type of wastewater and the dilution rate. The sensor signals observed by the gas sensor array were correlated with the dilution factor (OU) calculated by the air dilution sensory test with several wastewater ($r^2=0.920{\sim}0.997$), except the sensor signals of sensor D measured in the plating plant wastewater. It seems likely that the gas sensor array plays a role in the evaluation of odor in wastewater and is useful tool for on-site odor monitoring in the wastewater facilities.

Characterization of Ceramic Oxide Layer Produced on Commercial Al Alloy by Plasma Electrolytic Oxidation in Various KOH Concentrations

  • Lee, Jung-Hyung;Kim, Seong-Jong
    • 한국표면공학회지
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    • 제49권2호
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    • pp.119-124
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    • 2016
  • Plasma electrolytic oxidation (PEO) is a promising coating process to produce ceramic oxide on valve metals such as Al, Mg and Ti. The PEO coating is carried out with a dilute alkaline electrolyte solution using a similar technique to conventional anodizing. The coating process involves multiple process parameters which can influence the surface properties of the resultant coating, including power mode, electrolyte solution, substrate, and process time. In this study, ceramic oxide coatings were prepared on commercial Al alloy in electrolytes with different KOH concentrations (0.5 ~ 4 g/L) by plasma electrolytic oxidation. Microstructural and electrochemical characterization were conducted to investigate the effects of electrolyte concentration on the microstructure and electrochemical characteristics of PEO coating. It was revealed that KOH concentration exert a great influence not only on voltage-time responses during PEO process but also on surface morphology of the coating. In the voltage-time response, the dielectric breakdown voltage tended to decrease with increasing KOH concentration, possibly due to difference in solution conductivity. The surface morphology was pancake-like with lower KOH concentration, while a mixed form of reticulate and pancake structures was observed for higher KOH concentration. The KOH concentration was found to have little effect on the electrochemical characteristics of coating, although PEO treatment improved the corrosion resistance of the substrate material significantly.

Activated Carbon-Embedded Reduced Graphene Oxide Electrodes for Capacitive Desalination

  • Tarif Ahmed;Jin Sun Cha;Chan-gyu Park;Ho Kyong Shon;Dong Suk Han;Hyunwoong Park
    • Journal of Electrochemical Science and Technology
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    • 제14권3호
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    • pp.222-230
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    • 2023
  • Capacitive deionization of saline water is one of the most promising water purification technologies due to its high energy efficiency and cost-effectiveness. This study synthesizes porous carbon composites composed of reduced graphene oxide (rGO) and activated carbon (AC) with various rGO/AC ratios using a facile chemical method. Surface characterization of the rGO/AC composites shows a successful chemical reduction of GO to rGO and incorporation of AC into rGO. The optimized rGO/AC composite electrode exhibits a specific capacitance of ~243 F g-1 in a 1 M NaCl solution. The galvanostatic charging-discharging test shows excellent reversible cycles, with a slight shortening in the cycle time from the ~260th to the 530th cycle. Various monovalent sodium salts (NaF, NaCl, NaBr, and NaI) and chloride salts (LiCl, NaCl, KCl, and CsCl) are deionized with the rGO/AC electrode pairs at a cell voltage of 1.3 V. Among them, NaI shows the highest specific adsorption capacity of ~22.2 mg g-1. Detailed surface characterization and electrochemical analyses are conducted.