• 제목/요약/키워드: Electronic transport

검색결과 908건 처리시간 0.025초

BCP를 엑시톤 억제층으로 사용한 유기 광기전력 소자의 특성 (Properties of the Exciton Blocking Layer with BCP in Organic Photovoltaic cell)

  • 오현석;이준웅;이원재;김태완
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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    • pp.273-274
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    • 2005
  • Photovoltaic effects in organic solar cell were studied in a cell configuration of ITO/PEDOT:PSS/CuPc(20nm)/$C_{60}$(40nm)/BCP/Al(150nm) at room temperature. Here, the BCP layer works as an exciton blocking layer. The exciton blocking layer must transport electrons from the acceptor layer to the metal cathode with minimal increase in the total cell series resistance and should absorb damage during cathode deposition. Therefore, a proper thickness of the exciton blocking layer is required for an optimized photovoltaic cell. Several thicknesses of BCP were made between $C_{60}$ and Al. And we obtained characteristic parameters such as short-circuit current, open-circuit voltage, and power conversion efficiency of the device under the illumination of AM 1.5.

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물류 프로세스 표준화 연구 (The Study of Logistics Process Standardization)

  • 박순호;박수민
    • 디지털산업정보학회논문지
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    • 제7권1호
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    • pp.173-183
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    • 2011
  • Global logistics including Korea had developed at various fields through the developed IT technology. In addition, in changing into Internet based digital economy times, economic and logistics activities became extending into worldwide over the cross-border. Logistics activity performed by off-line rapidly changed in real environment. But, unfortunately business process modeling about the whole logistics was not happened, even though process modeling had done by transport stages or logistics entities. Therefore, it is difficult to grasp the whole logistics. Additional cost and time was requested due to no association between logistics entities and invisibility. So, this paper has to be process modeling for logistics industry domain. For objective modeling, work area shall be divided and it extracts general work process per each area. And then it defines subprocess of general work process. Cargo tracking in logistics industry domain means to grasp the status and present states at transportation or storage stage. This paper defines business process and data model for electronic processed work area using the UN/CEFACT standard modeling methodology.

Band Structure Engineering of Monolayer MoS2 by Surface Ligand Functionalization

  • Lee, Sang Yoon;Ramzan, Sufyan
    • EDISON SW 활용 경진대회 논문집
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    • 제4회(2015년)
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    • pp.367-370
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    • 2015
  • Monolayer transition metal dicalcogenide (TMDC) materials are currently attracting extensive attention due to their distinctive electronic, transport, and optical properties. For example, monolayer $MoS_2$ exhibits a direct band gap in the visible frequency range, which makes it an attractive candidate for the photocatalytic water splitting. For the photoelectrochemical water splitting, the appropriate band edge positions that overlap with the water redox potential are necessary. Similarly, appropriate band level alignments will be crucial for the light emitting diode and photovoltaic applications utlizing heterojunctions between two TMDC materials. Carrying out first-principles calculations, we here investigate how the band edges of $MoS_2$ can be adjusted by surface ligand functionalization. This study will provide useful information for the realization of ligand-based band engineering of monolayer $MoS_2$ for various electronic, energy, and bio device applications.

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e ̄-CF$_4$산란의 전자이동속도 및 특성에너지 연구 (Electron Swarm Drift Velocity and Characteristic Energy in e$^{[-10]}$ -CF$_4$Scattering)

  • 임상원;유회영;김상남;하성철
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1996년도 추계학술대회 논문집
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    • pp.169-174
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    • 1996
  • In this paper, the electron transport characteristic in CF$_4$has been analysed over the E/N range 1~300(Td) by a two-term approximation Boltzmann equation method and by a Monte Carlo simulation. The alteration of cross sections from the literature is avoided as much as possible in the analysis. The motion has been calculated to give swarm parameters for the electron drift velocity(W), diffusion coefficient(D$_{L}$), the ratio of the diffusion coefficient to the mobility(D$_{L}$/$\mu$), mean energy($\varepsilon$), the electron energy distribution function. The electron energy distribution function has been analysed in CF$_4$at E/N=50, 100 and 200(Td) for a case of the equilibrium region in the mean electron energy. The results of Boltzmann equation and Monte Carlo simulation have been compared with experimental data by Y. Nakamura and M. Hayashi.shi.

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유기 발광 소자의 바이어스 전압에 따른 유전 특성 (Dielectric Properties depending on Bias Voltage in Organic Light-emitting Diodes)

  • 오용철;이준웅
    • 한국전기전자재료학회논문지
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    • 제18권11호
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    • pp.1038-1042
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    • 2005
  • We have investigated dielectric properties depending on bias voltage in organic light-emitting diodes using 8-hydroxyquinoline aluminum $(Alq_3)$ as an electron transport and emissive material. We analyzed the dielectric properties of organic light-emitting diodes using impedance of characteristics. Impedance characteristics was measured complex impedance Z and phase $\theta$ in the frequency range of 40 Hz to $10^8$ Hz. We obtained complex electrical conductivity, dielectric constant, and loss tangent $(tan\delta)$ of the device at room temperature. From these analyses, we are able to interpret a conduction mechanism and dielectric properties contributed by an interfacial and orientational polarization.

The Moving Photocarrier Grating (MPG) Technique for the Transport Properties of α-Se:As Films

  • Park, Chang-Hee;Lee, Kwang-Sei;Kim, Jeong-Bae;Kim, Jae-Hyung
    • Transactions on Electrical and Electronic Materials
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    • 제6권6호
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    • pp.280-283
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    • 2005
  • The moving photocarrier grating (MPG) technique for the determination of the carrier mobilities and the recombination lifetime of $\alpha$-Se:As films has been studied. The electron and hole drift mobility and the recombination lifetime of $\alpha$-Se films with arsenic (As) additions have been obtained from measurement of the short circuit current density $j_{sc}$ as a function of grating velocity and spatial period. The hole mobility decreases due to defect density of hole traps when x exceeds 0.003, whereas the hole mobility increases for the case of low As addition (x$\le$0.003). We have found an increase in hole drift mobility and recombination lifetime, especially when As with (x = 0.003) is added into the $\alpha$-Se film.

교류자장에 대한 Bi-2223테이프의 직류전압-전류 특성 (DC voltage-current characteristics of a Bi-2223 tape in AC magnetic fields)

  • 허대행;류경우
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 춘계학술대회 논문집 기술교육전문연구회
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    • pp.123-126
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    • 2003
  • 고온초전도테이프의 전력부야 응용에서 자화손실과 함께 매우 중요한 통전손실에 대한 실험적 조사 연구를 한 결과, 외부자장이 커짐에 따라서 직류전압이 급격히 증가하였으며, 자장의 세기가 동일할지라도 교류인 경우가 직류인 경우보다 대단히 크다. 그리고 외부교류자장에 대한 직류전압-전류 특성으로부터 정의되는 동저항 또한 외부교류자장의 세기에 따라서 상이하지만 테이프의 임계전류에서 전기저항$(3.7\;{\mu}{\Omega}/m)$과 비교하여 작게는 수배에서부터 크게는 수백 배까지 증가한다.

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구형 집속 빔 핵융합 장치에서 그리드 음극 구조의 최적 설계 (Optimal Design of Grid Cathode Structure in Spherically Convergent Beam Fusion Device)

  • 주흥진;박정호;황휘동;최승길;고광철
    • 한국전기전자재료학회논문지
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    • 제21권4호
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    • pp.381-387
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    • 2008
  • Neutron production rate in spherically convergent beam fusion(SCBF) device as a portable neutron source strongly depends on the ion current and the grid cathode structure. In this paper, as the process of design and analysis, Design of Experiment(DOE) based on the results by Finite Element Method-Flux Corrected Transport(FEM-FCT) method is employed to calculate the ion current. This method is very useful to find optimal design conditions in a short time. Number of rings, radius of rings, and distance between the grid cathode and center are selected as control factors. From the results in the optimized model, the higher ion current is calculated and deeper potential well is also observed.

모바일 전자장비 냉각용 Micro-CPL내 형상크기변화에 따른 열성능 해석 (Effect of Groove and Channel Size on the Thermal Transport Capacity of Micro-Capillary Pumped Loop for Mobile Electronic Device Cooling System)

  • 김병기;서정세;황건;문석환;배찬효
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2005년도 동계학술발표대회 논문집
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    • pp.329-334
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    • 2005
  • As more high power wide band gap devices are being utilized. the thermal management issues associated with these devices need to be resolved. High power small devices dissipate excessive heat that must be cooled, but traditional cooling methods are insufficient to provide such a cooling means. This paper will evaluate a micro-capillary pumped loop thermal management system that is incorporated into the shim of the device, taking advantage of phase-change to increase the thermal conductivity of the system. The results of the modeling of the thermal management system will be discussed.

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열간 정수압 소결(HIP)에 의한 Y-Ba-Cu-O계rhdhs 초전도체의 제작 및 특성 (Properties of Y-Ba-Cu-O High Tc superconductor prepared by sintering, sintering+HIP encapsulation)

  • 김종문;백수현
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1988년도 추계학술대회 논문집
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    • pp.36-40
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    • 1988
  • High TC Y-Ba-Cu-O Superconductors were fabricated by sintering, sinter+HIP encapsulation. Specimens were sintered at 920$^{\circ}C$∼960$^{\circ}C$. A part of sintered specimens were treated by HIP, and HIP conditions were 150 MPa, 880$^{\circ}C$, 30min under the Ar atmosphere. The relative density of HIP specimens was increased 5∼8% in comparison with sintered one(90∼93% relative density). X-ray analysis represented the orthorhobic-tetragonal phase transition with annealing condition. Tc measurements showed a sharp drp within 3$^{\circ}C$, 91K onset and 89K offset. Transport current density(Jc) of sintered specimens showed typically∼159A/㎤ but that of sinter+HIP encapsulation was decreased to∼89A/㎤ because of insufficient oxygen diffusion, Hardness(H) and Toughness(Kc) were increased to 38GPa; and 2.9 MPam$\^$$\frac{1}{2}$/, respectively.

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