• 제목/요약/키워드: junction structure

검색결과 484건 처리시간 0.026초

White Organic Light-emitting Diodes using the Tandem Structure Incorporating with Organic p/n Junction

  • Lee, Hyun-Koo;Kwon, Do-Sung;Lee, Chang-Hee
    • Journal of Information Display
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    • 제8권2호
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    • pp.20-24
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    • 2007
  • Efficient white organic light-emitting diodes are fabricated with the blue and red electroluminescent (EL) units electrically connected in a stacked tandem structure by using a transparent doped organic p/n junction. The blue and red EL units consist of the light-emitting layer of 1,4-bis(2,2-diphenyl vinyl)benzene (DPVBi) and 4-dicyanomethylene-2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[i,j] quinolizin-8-yl)vinyl]-4H-pyran) (DCM2) doped tris(8-hydroxyquinoline) aluminum $(Alq_3)$, respectively. The organic p-n junction consists of ${\alpha}-NPD$ doped with $FeCl_3$ (15 % by weight ratio) and $Alq_3$ doped with Li (10 %). The EL spectra exhibit two peaks at 448 and 606 nm, resulting in white light-emission with the Commission Internationale d'Eclairage (CIE) chromaticity coordinates of (0.36, 0.24). The tandem device shows the quantum efficiency of about 2.2 % at a luminance of 100 $cd/m^2$, higher than individual blue and red EL devices.

FDTD법을 이용한 유도성벽을 가지는 $\pi$분기 급전도파관의 설계에 관한 연구 (A study on design for the $\pi$-junction of a feeder waveguide with an inductive wall using FDTD method)

  • 민경식;김광욱;고지원;김동철;임학규
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2000년도 춘계종합학술대회
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    • pp.143-146
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    • 2000
  • This paper presents a study on design for the k-junction of a feeder waveguide with an inductive wall using FDTD method. The feed structure consists of a single waveguide plated on the same layer as radiating waveguide and is characterized by the unit divider, railed a $\pi$-Junction. This $\pi$-Junction with an inductive wall splits part of the power into two branch waveguide through one coupling window, and can excite densely arrayed waveguide at equal phase and amplitude. The power dividing characteristics of a $\pi$ -Junction obtained by FDTD method are compared with one of Galerkin's method of moments. The scattering matrices a $\pi$ -junction calculated by FDTD method are realized.

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Deep Trench Filling 기술을 적용한 600 V급 Super Junction Power MOSFET의 최적화 특성에 관한 연구 (A Study on 600 V Super Junction Power MOSFET Optimization and Characterization Using the Deep Trench Filling)

  • 이정훈;정은식;강이구
    • 한국전기전자재료학회논문지
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    • 제25권4호
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    • pp.270-275
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    • 2012
  • Power MOSFET(metal oxide silicon field effect transistor) operate voltage-driven devices, design to control the large power switching device for power supply, converter, motor control, etc. But on-resistance characteristics depending on the increasing breakdown voltage spikes is a problem. So 600 V planar power MOSFET compare to 1/3 low on-resistance characteristics of super junction MOSFET structure. In this paper design to 600 V planar MOSFET and super junction MOSFET, then improvement of comparative analysis breakdown voltage and resistance characteristics. As a result, super junction MOSFET improve on about 40% on-state voltage drop performance than planar MOSFET.

Bi-directional Two Terminal Switching Device with Metal/P/N+or Metal/N/P+ Junction

  • Kil, Gyu-Hyun;Lee, Sung-Hyun;Yang, Hyung-Jun;Lee, Jung-Min;Song, Yun-Heub
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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    • pp.386-386
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    • 2012
  • We studied a bilateral switching device for spin transfer torque (STT-MRAM) based on 3D device simulation. Metal/P/N+or Metal/N/P+ junction device with $30{\times}30nm2$ area which is composed of one side schottky junction at Metal/P/N+ and Metal/N/P+ provides sufficient bidirectional current flow to write data by a drain induced barrier lowering (DIBL). In this work, Junction device confirmed that write current is more than 30 uA at 2 V, It is also has high on-off ratio over 105 under read operation. Junction device has good process feasibility because metal material of junction device could have been replaced by bottom layer of MTJ. Therefore, additional process to fabricate two outer terminals is not need. so, it provides simple fabrication procedures. it is expected that Metal/P/N+ or Metal/N/P+ structure with one side schottky junction will be a promising switch device for beyond 30 nm STT-MRAM.

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Determination of energetically preferable Au-S contact atomic structure in stretched single-molecule junctions

  • Ko, Kwan Ho
    • EDISON SW 활용 경진대회 논문집
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    • 제3회(2014년)
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    • pp.409-411
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    • 2014
  • Based on the first-principles computations, the nature of the microscopic geometry of the molecule-electrode contacts was addressed. The single-molecule junction was prepared by connecting hexanediothiolate (HDT) to Au(111) electrodes via one, two, and three Au adatoms having coordination number of one (CN1), two (CN2), and, three (CN3), respectively. The contact atomic structure and energy of the stretched Au-HDT-Au junction was observed. The analysis revealed that the contact geometry with lowest coordination number (CN1) is energetically more stable than CN2 and CN3.

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T-접합 도파관의 수치적 해석 (Numerical Analysis of Waveguide T-Junction)

  • 천창율;정진교
    • 산업기술연구
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    • 제13권
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    • pp.25-31
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    • 1993
  • This paper presents an analysis of microwave device component. An H-Plane waveguide component with arbitrary shape is analyzed using finite element method(FEM) cooperated with boundary element method(BEM). The finite element method(FEM) is applied to the junction region and the boundary element method(BEM) to the waveguide region. For the application of BEM in the waveguide structure, a ray representation of the waveguide Green's function is used. The proposed technique was applied to the analysis of the waveguide inductive junction to compare the numerical result with the result of the mode matching technique. The comparison showed good agreements between the two results. Transmitted powers were also computed in T-junction waveguides for the various shape of the junction area.

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대용량 전력변환용 초접합 IGBT 개발에 관한 연구 (The Develop of Super Junction IGBT for Using Super High Voltage)

  • 정헌석;강이구
    • 한국전기전자재료학회논문지
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    • 제28권8호
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    • pp.496-500
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    • 2015
  • This paper was proposed the theoretical research and optimal design 3000V super junction NPT IGBT for using electrical automotive and power conversion. Because super junction IGBT was showed ultra low on resistance, it was structure that can improve the thermal characteristics of conventional NPT IGBT. The electrical characteristics of super junction NPT IGBT were 2.52 V of on state voltage drop, 4.33 V of threshold voltage and 2,846 V breakdown voltage. We did not obtaing 3,000 V breakdown voltage but we will obtain 3,000 V breakdown voltage through improving p pillar layer. If we are carried this research, This device will be used electrical automotive, power conversiton and high speed train.

사파이어 기판의 다른 결정방향 위에 제작된 YBCO step-edge 접합의 특성 (Properties of YBCO Step-edge Junction Fabricated on Different Crystal Orientation of Sapphire Substrate)

  • 임해용;김인선;박용기;박종철
    • Progress in Superconductivity
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    • 제3권1호
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    • pp.60-64
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    • 2001
  • We have studied properties of step-edge Junction prepared with crystal orientation of sapphire substrate. The Step on sapphire substrates fabricated by conventional photolithography method and Ar ion milling method. $CeO_2$ buffer layer and in-situ YBCO thin film were deposited on the stepped sapphire substrates by a pulsed laser deposition method with the predetermined optimized condition. The step angle was centre fled low angle of about $25^{\circ}$. The YBCO film thickness was varied to obtain various thickness ratios of the film to the step height in a range from 0.7 to 1.2. I-V curves of junction were showed RSJ-behavior, double junction structure, and hysteresis due to the crystal orientation of substrate.

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Deducing Isoform Abundance from Exon Junction Microarray

  • Kim Po-Ra;Oh S.-June;Lee Sang-Hyuk
    • Genomics & Informatics
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    • 제4권1호
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    • pp.33-39
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    • 2006
  • Alternative splicing (AS) is an important mechanism of producing transcriptome diversity and microarray techniques are being used increasingly to monitor the splice variants. There exist three types of microarrays interrogating AS events-junction, exon, and tiling arrays. Junction probes have the advantage of monitoring the splice site directly. Johnson et al., performed a genome-wide survey of human alternative pre-mRNA splicing with exon junction microarrays (Science 302:2141-2144, 2003), which monitored splicing at every known exon-exon junctions for more than 10,000 multi-exon human genes in 52 tissues and cell lines. Here, we describe an algorithm to deduce the relative concentration of isoforms from the junction array data. Non-negative Matrix Factorization (NMF) is applied to obtain the transcript structure inferred from the expression data. Then we choose the transcript models consistent with the ECgene model of alternative splicing which is based on mRNA and EST alignment. The probe-transcript matrix is constructed using the NMF-consistent ECgene transcripts, and the isoform abundance is deduced from the non-negative least squares (NNLS) fitting of experimental data. Our method can be easily extended to other types of microarrays with exon or junction probes.

Direct Printable Nanowire p-n Junction device

  • Lee, Tae-Il;Choi, Won-Jin;Kar, Jyoti Prakash;Moon, Kyung-Ju;Lee, Min-Jung;Jun, Joo-Hee;Baik, Hong-Koo;Myoung, Jae-Min
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2010년도 춘계학술발표대회
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    • pp.30.2-30.2
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    • 2010
  • Nano-scale p-n junction can generate various nano-scale functional devices such as nanowire light emitting diode, nanowire solar cell, and nanowire sensor. The core shell type nanowire p-n junction has been considered for the high efficient devices in many previous reports. On the other hand, although device efficiency is relatively lower, the cross bar type p-n junction has simple topological structure, suggested by C.M. Lieber group, to integrate easily many p-n junction devices in one board. In this study, for the integration of the cross bar nanowire p-n junction device, a simple fabrication route, employed dielectrophoretic array and direct printing techniques, was demonstrated by the successful fabrication and programmable integration of the nanowire cross bar p-n junction solar cell. This direct printing process will give the single nanowire solar cell the opportunity of the integration on the circuit board with other nanowire functional devices.

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