• 제목/요약/키워드: capacitance ratio

검색결과 258건 처리시간 0.029초

고분자 융해 반응을 이용한 전기 이중층 커패시터용 다공성 활성탄 제조 (Fabrication of Activated Porous Carbon Using Polymer Decomposition for Electrical Double-Layer Capacitors)

  • 성기욱;신동요;안효진
    • 한국재료학회지
    • /
    • 제29권10호
    • /
    • pp.623-630
    • /
    • 2019
  • Because of their excellent stability and highly specific surface area, carbon based materials have received attention as electrode materials of electrical double-layer capacitors(EDLCs). Biomass based carbon materials have been studied for electrode materials of EDLCs; these materials have low capacitance and high-rate performance. We fabricated tofu based porous activated carbon by polymer dissolution reaction and KOH activation. The activated porous carbon(APC-15), which has an optimum condition of 15 wt%, has a high specific surface area($1,296.1m^2\;g^{-1}$), an increased average pore diameter(2.3194 nm), and a high mesopore distribution(32.4 %), as well as increased surface functional groups. In addition, APC has a high specific capacitance($195F\;g^{-1}$) at low current density of $0.1A\;g^{-1}$ and excellent specific capacitance($164F\;g^{-1}$) at high current density of $2.0A\;g^{-1}$. Due to the increased specific surface area, volume ratio of mesopores, and surface functional groups, the specific capacitance and high-rate performance increased. Consequently, the tofu based activated porous carbon can be proposed as an electrode material for high-performance EDLCs.

SiNx의 Substrate temperature와 gas ratio의 변화에 따른 특성

  • 백경현;장경수;이원백;이준신
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2010년도 제39회 하계학술대회 초록집
    • /
    • pp.250-250
    • /
    • 2010
  • Flexible display의 발전에 따라 점차 고온 공정에서 plastic 기판에 영향을 주지 않는 저온 공정으로 변화해 가고 있다. 이러한 발전에 따라 공정온도에 따른 SiNx의 특성 분석을 위해 우선 150C~300C에서 SiNx의 박막을 증착하였다. gas ratio (SiH4:NH3=4:60)와 Power (50W), 공정시간(25min)을 고정하고 온도만을 가변하여 박막의 특성을 분석하였다. 이후에 150C로 온도를 고정 후 gas ratio를 가변하고 Power (40W)와 온도(150C)는 고정 후 실험을 진행하여, 150C에서 최적화된 gas ratio를 알아내도록 하였다. 위의 실험은 p-type 실리콘 웨이퍼 위에 SiNx 박막 증착 후 굴절률과 증착률을 측정하였고, Al 전극을 증착하여 MIS구조를 구현하여, gate voltage에 따른 capacitance를 측정하였다. 이번 논문에서는 SiNx의 Substrate temperature와 gas ratio의 변화에 따른 다양한 특성을 확인하고 이를 체계적으로 분석하였다.

  • PDF

미세가공 진동형 자이로스코프의 특성 감지 회로의 설계에 관한 연구 (Design of the Detection Circuitry for the Characteristics of Micromachined Vibrating Gyroscope)

  • 우영신;변광균;서일원;성만영
    • 대한전기학회논문지:전기물성ㆍ응용부문C
    • /
    • 제48권10호
    • /
    • pp.687-692
    • /
    • 1999
  • A new technique to measure low level capacitance variations of the gyroscope is proposed and verified by computer simulation. It is based on the new CV(capacitance-voltage) converter circuit biased by dc current source and the peak detector without low pass filter. The CV converter biased by dc current source provides good signal-to-noise ratio and this setup of the detection circuitry without low pass filter makes it possible to provide short settling time, that is, higher speed of measurement and wide operation range if only a few parameters are adjusted. The key parameters that affect the performance of the detection circuitry are illustrated and computer simulation results are presented. The demonstrated detection circuitry shows linear response from 10 fF to 130 fF at 10 kHz and shows good linearity.

  • PDF

혼합된 PVP-PVA 유기 게이트 절연막이 유기 박막 트랜지스터의 전기적 특성에 미치는 영향에 대한 연구

  • 조병근;김기중;노용한
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2009년도 추계학술대회 논문집
    • /
    • pp.42-42
    • /
    • 2009
  • To make up for the disadvantages of PVA gate, we blend PVP(20% wt) with PVA(5% wt) as a gate material. The best ratio for the mixture was 5:5, PVP-PVA blended gate used MIM structure showed better performance in leakage current and capacitance. PVP-PVA blended gate was fabricated by spin-coating process and pentacene was used as an organic TFT channel layer by thermal evaporation. Overall OTFT performance has also increased as PVP-PVA blended gate has relatively lower leakage current and higher capacitance than pure PVA gate has.

  • PDF

콘덴서형 단상 유도전동기의 설계에 관한 연구 (A Study on the Design of Single-Phase Capacitor-Run Induction Motor)

  • 김복기;박준석;정태경
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1996년도 하계학술대회 논문집 A
    • /
    • pp.121-123
    • /
    • 1996
  • Capacitor-run motor has a capacitor id series with the auxiliary winding for normal running connections. After the shape of stator and rotor are determined, the motor is designed with variables such as winding distributions or capacitance except punching variables. In this paper, the winding distribution and the turn ratio was taken as design variables because the winding distribution affects the torque and efficiency. And capacitance was selected as an additional variable. Simulation results show the validity of proposed method.

  • PDF

Pt/SBN/Pt 캐패시터 박막의 유전특성 (Dielectric Properties of Pt/SBN/Pt Capacitor Thin film)

  • 김진사;오용철;신철기;배덕권
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2009년도 제40회 하계학술대회
    • /
    • pp.1250_1251
    • /
    • 2009
  • The SBN thin films are deposited on Pt-coated electrode(Pt/Ti/$SiO_2$/Si) using RF sputtering method at various deposition conditions. The capacitance of SBN thin films were increased with the increase of Ar/$O_2$ ratio and RF power, respectively. Also, The capacitance of SBN thin films were increased with the increase of deposition temperature.

  • PDF

미세 구멍가공을 위한 전극성형 가공특성에 관한 연구 (A Study on the Characteristics of Electrode Fabrication for Micro Hole-making)

  • 이주경;이종항;박철우;조웅식
    • 대한기계학회논문집A
    • /
    • 제31권11호
    • /
    • pp.1053-1058
    • /
    • 2007
  • Micro-EDM technology (or the manufacture of miniature parts is used to make a micro hole. Two electrode shaping methods, mechanical electrode grinding and WEDG technique, have been studied. In this study, an electrode shaping method by using previously machined hole is introduced in order to obtain an optimal hole-making condition. Key factors such as applied voltage, capacitance, feedrate, and hole-dimension have an influence on the fabricating error of electrode shaping, which are taper ratio of a hole, electrode form accuracy, and electrode surface. Therefore, we try to investigate the optimal fabricating of electrode shaping from various experiments. Results from experiments, it was able to minimize the electrode fabricating error as voltage increases, and also applied feedrate and capacitance decreases.

증착온도에 따른 SBN 박막의 미세구조 및 특성 (Microstructure and Properties of SBN Thin film with Deposition Temperature)

  • 김진사;최운식;김충혁
    • 전기학회논문지
    • /
    • 제58권3호
    • /
    • pp.544-547
    • /
    • 2009
  • The $Sr_{0.7}Bi_{2.3}Nb_{2}O_{9}$(SBN) thin films are deposited on Pt-coated electrode(Pt/Ti/$SiO_2$/Si) using RF sputtering method at various deposition temperature. The optimum conditions of RF power and Ar/$O_2$ ratio were 60[W] and 70/30, respectively. Deposition rate of SBN thin films was about 4.17[nm/min]. The crystallinity of SBN thin films were increased with increase of deposition temperature in the temperature range of $100{\sim}400[^{\circ}C]$, the surface rougness showed about 4.33[nm]. The capacitance of SBN thin films were increased with the increase of deposition temperature.

PECVD에 의해 형성된 oxynitride막의 전기적 특성 (Electrical properities of oxynitride film by PECVD)

  • 최현식;배성식;서용진;김창일;최동진;장의구
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 1993년도 추계학술대회 논문집
    • /
    • pp.97-102
    • /
    • 1993
  • According as the high integrity of the semi conductor devices is definited required, the concern on the multi-layered wiring, and three-dimensional devices is growing these days. Therefore, plasma-enhanced chemical vapored deposition(PECVD) enables low-teperature process and is widely used, but it causes the instability of the devices due to a lot of impurities within the film. The PECVD oxynitride was formed by changing the gas ratio of (N$_2$O) to (N$_2$+NH$_3$). It's contained a small portion of hydrogen, had higher refrctive index and capacitance than oxide, and showed the capacitance increasement and the chemical stabi1ity. This is caused by nitrogen distribution increase of the interface lather than within the film.

  • PDF

$Sr_{0.7}Bi_{2.3}Nb_2O_9$ 박막의 구조적인 특성 (Structural Properties of $Sr_{0.7}Bi_{2.3}Nb_2O_9$ Thin Film)

  • 김진사;최영일;조춘남;최운식;김충혁
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
    • /
    • pp.185-186
    • /
    • 2008
  • The $Sr_{0.7}Bi_{2.3}Nb_2O_9$(SBN) thin films are deposited on Pt-coated electrode(Pt/Ti/SiO2/Si) using RF sputtering method at various substrate temperature. The optimum conditions of RF power and Ar/O2 ratio were 60[W] and 70/30, respectively. The rougness showed about 4.33[nm]. Deposition rate of SBN thin films was about 4.17[nm/min]. The capacitance of SBN thin films were increased with the increase of substrate temperature.

  • PDF