• 제목/요약/키워드: polycrystalline

검색결과 1,290건 처리시간 0.025초

X-ray Response Characteristic of Zn in the Polycrystalline Cd1-xZnxTe Detector for Digital Radiography

  • Kang, Sang-Sik
    • Transactions on Electrical and Electronic Materials
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    • 제3권2호
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    • pp.28-31
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    • 2002
  • The Cdl-xZnxTe film was fabricated by thermal evaporation for the flat-panel X-ray detector. The stoichimetric ratio and the crystal structure of a polycrystalline Cd$_{1-x}$ Zn$_{x}$Te were investigated by EPMA and XRD, respectively. The leakage current and X-ray sensitivity of the fabricated films were measured to analyze the X-ray response characteristic of Zn in the polycrystalline CdZnTe thin film. The leakage current and the output charge density of Cd$_{0.7}$Zn$_{0.3}$Te thin film were measured to 0.37 nA/cm$^2$ and 260 pc/cm$^2$ at an applied voltage of 2.5 V/${\mu}{\textrm}{m}$, respectively. Experimental results showed that the increase of Zn doping rates in Cd$_{1-x}$ Zn$_{x}$Te detectors reduced the leakage current and improved the signal to noise ratio significantly.

스트레스에 따른 다결정 실리콘 TFT의 영향 (Characteristics of Polycrystalline Silicon TFT with Stress-Bias)

  • 백도현;이용재
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 영호남학술대회 논문집
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    • pp.233-236
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    • 2000
  • Polycrystalline Silicon Thin Film Transistors(Poly-Si TFT's), fabricated at temperature lower than $600^{\circ}C$ are now largely used in many applications, particularly in large area electrons. In this work, electrical stress effects on Poly-Si TFT's fabricated by Solid Phase Crystal(SPC) was investigated by measuring electric properities such as transfer and output characteristics, and channel conductance. Consequently, It is turned out that it should be noted the output characteristics, drain current and channel conductance, strongly degrade around origin.

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주름진 다결정 3C-SiC 공진기의 특성 (Characteristics of corrugated polycrystalline 3C-SiC resonators)

  • 원영태년;정귀상
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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    • pp.251-251
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    • 2008
  • In this work, appropriate corrugated structure is suggested to increase resonant frequency of resonators. Micro beam resonators based on polycrystalline 3C-SiC films which have a two-side corrugation along the length of beams were simulated by finite element method and compared to a same - size flat rectangular. With the dimension of $36\times12\times0.5{\mu}m^3$, the flat cantilever has resonant frequency of 746 kHz. Meanwhile, with this size only corrugation width of $6{\mu}m$ and depth of $0.4{\mu}m$, the corrugated cantilever reaches the resonant frequency at 1.252 MHz, and is 68% larger than that of flat type.

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The microstructure of polycrystalline silicon thin film that fabricated by DC magnetron sputtering

  • Chen, Hao;Park, Bok-Kee;Song, Min-Jong;Park, Choon-Bae
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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    • pp.332-333
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    • 2008
  • DC magnetron sputtering was used to deposit p-type polycrystalline silicon on n-type Si(100) wafer. The influence of film microstructure properties on deposition parameters (DC power, substrate temperature, pressure) was investigated. The substrate temperature and pressure have the important influence on depositing the poly-Si thin films. Smooth ploy-Si films were obtained in (331) orientation and the average grain sizes are ranged in 25-30nm. The grain sizes of films deposited at low pressure of 10mTorr are a little larger than those deposited at high pressure of 15mTorr.

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MEMS 부품을 위한 다결정 박막의 탄성 물성치 추출 시스템과 다결정 재료의 적용 (Elastic Property Extraction System of Polycrystalline Thin-Films for Micro-Electro-Mechanical System Device and Application to Polycrystalline Materials)

  • 정향남;최재환;정희택;이준기
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2004년도 추계학술발표대회 논문집
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    • pp.19-22
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    • 2004
  • A numerical system to extract effective elastic properties of polycrystalline thin-films for MEMS devices is already developed. In this system, the statistical model based on lattice system is used for modeling the microstructure evolution simulation and the key kinetics parameters of given micrograph, grain distributions and deposition process can be extracted by inverse method proposed in the system. In this work, the effective elastic properties of polysilicon, $BaTiO_3\;and\;ZrTiO_4$ are extracted using this system and by employing the fraction of the potential site($f_P$) as a kinetics parameter for the microstructure evolution, the statistical tendency of these materials is studied.

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PCD 공구를 이용한 티타늄 합금의 미세 가공 (Micro Machining of Titanium Alloy Using Polycrystalline Diamond Tools)

  • 문인용;김보현
    • 한국정밀공학회지
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    • 제30권3호
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    • pp.284-291
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    • 2013
  • Micro cutting of titanium alloy by polycrystalline diamond (PCD) tools was studied. Micro electro discharge machining (MEDM) was used to fabricate customized micro shaping tools from PCD blank. The tool was used to machine micro grooves on Ti alloy and the effects of depth of cut and machining length on tool wear, burr and surface roughness were studied. The shaping tool has cutting edge of a few ${\mu}m$. The crater size of the tool surface was increased with increasing capacitance of EDM machining conditions, which was used to control the surface roughness of the machined micro grooves.

유한요소법을 이용한 다결정 고체의 복합스케일 모델링 (Strongly-coupled Finite Element Method Approach to Multi-scale Modelingof Polycrystalline Solids)

  • 한동석;폴 도슨
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2006년도 정기 학술대회 논문집
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    • pp.531-534
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    • 2006
  • A multi-scale (macro-micro) finite element framework for analysis of polycrystalline solids is suggested. The proposed frame work is strongly-coupled in a sense that the two scale calculation is performed at the same time. The issue of averaging micro-scale material stress and stiffness is addressed and a strategy is proposed. The proposed framework is implemented and applied to two examples having different geometries and loading modes. It is concluded that the proposed multi-scale framework can be used for more detailed and accurate analysis compared with the single-scale finite element analysis.

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텅스텐 실리사이드 상의 얇은 $SiO_2/Si_3N_4$ 막의 특성 평가 (Characterization of Thin $SiO_2/Si_3N_4$ Film on $WSi_2$)

  • 구경원;홍봉식
    • 한국진공학회지
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    • 제1권1호
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    • pp.183-189
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    • 1992
  • 텅스텐 실리사이드를 축적전극으로 하는 얇은 N/O(SiO2/Si3N4) 구조막의 특성을 다 결성 실리콘의 경우와 비교 평가하였다. 누설전류 및 항복전압이 향상되었고 축적용량은 감 소하였다. 용량 감소의 원인중의 하나는 텅스텐 실리사이드 상의 산화막 성장률이 다결성 실리콘 위에서 보다 빠른 것이고 둘째는 열처리에 따라 다결정 실리콘 내 도판트 불순물이 텅스텐 실리사이드를 통하여 외향확산하여 다결정 실리콘 내에 공핍층을 형성하게 되고 공 핍층 용량으로 인하여 축적용량이 감소하게 된다.

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결정입계의 선택적 식각을 이용한 다결정 규소 태양전지의 제작과 특성 (Fabrication and Characterization of Polycrystalline Silicon Solar Cells using Preferential Etching of Grain Boundaries)

  • 김상수;김철수;임동건;김도영;이준신
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 C
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    • pp.1430-1432
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    • 1997
  • A solar cell conversion effiency was degraded by grain boundary effect in polycrystalline silicon. To reduce these effects of the grain boundaries, we investigated various influencing factors such as preferential chemical etching of grain boundaries, grid design, transparent conductive thin film, and top metallization along grain boundaries. Pretreatment in $N_2$ atmosphere and gettering by $POCl_3$ and Al were performed to obtain polycrystalline silicon of the reduced defect density. Structural, electrical, and optical properties of solar cells were characterized. Improved conversion efficiencies of solar cell were obtained by a combination of Al diffusion into grain boundaries on rear side, fine grid finger, top Yb metal grid on Cr thin film of $200{\AA}$ and buried contact metallization along grain boundaries.

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다결정재의 이방성 탄.점소성 유한요소해석 (Anisotropic Elasto-Viscoplastic Finite Element Analysis for Polycrystalline Materials)

  • 이용신;김응주
    • 한국CDE학회논문집
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    • 제2권2호
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    • pp.71-76
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    • 1997
  • The deformations of polycrystalline materials are modelled by linking a constitutive equation for the crystallographic slip of a single crystal to the macroscopic behavior of the aggregate. In this study, anisotropic elasticity (lattice stretching) of a cubic crystal is incoporated into the anisotropic plasticity from crystallographic slip. The constitutive description for the aggregate, derived from a crystal plasticity theory, is used to formulate a Consistent Penalty Finite Element Method for the anisotropic elasto-viscoplastic deformation of polycrystalline materials. As an application, a plane-strain forging process is simulated and the effects of the initial textures on the deformation behavior of the workpiece are examined.

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