• 제목/요약/키워드: Zn-injection

검색결과 122건 처리시간 0.025초

EPMA를 이용한 ZnO 세라믹 바리스터 입계의 원소분포와 열화특성 분석 (Analysis of Element distribution and Degradation Characteristics in the grain boundary of ZnO Ceramic Varistors with EPMA)

  • 소순진;김영진;박영순;박춘배
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 춘계학술대회 논문집 전자세라믹스 센서 및 박막재료 반도체재료 일렉트렛트 및 응용기술
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    • pp.64-67
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    • 2000
  • Element distribution analysis and degradation characteristics of the ZnO varistors fabricated at the ambient sintering-process is investigated in this study. ZnO varistors made of Matsuoka's composition were fabricated by standard ceramic techniques. The ambient sintering-process is performed at the special electrical-furnace which is equipped with the vacuum system. The Gases of injection at sintering- process were oxygen, air, nitrogen and argon respectively. Element and quantitative analysis in the microstructure of ZnO varistors made use of EPMA equipment. Degradation characteristics were showed by DC degradation tests at $115{\pm}2\;^{\circ}C$ for period up to 13 h. From above analysis, it is found that at the DC degradation test the ZnO varistor sintered in oxygen atmosphere showed the excellent prop properties among them and these results could be explain by element and quantitative analysis in ZnO microstructure.

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상부전극 물질에 따른 CdZnTe 박막 특성 비교 연구 (The study of characteristics on metallic electrical contacts to CdZnTe based X-ray image detectors)

  • 공현기;강상식;차병열;조성호;김재형;남상희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.813-816
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    • 2002
  • We investigate the junction between CdZnTe and a variety of metals with the aim of determining whether the choice of metal can improve the performance of X-ray image detectors, in particular minimizing the dark current. The samples consist of $5{\mu}m$ thick CdZnTe with top electrodes formed from In, Al, and Au. For each metal, current transients following application of valtages from -10V to 10V are measured for up to 1 hour. We find that dark currents depending on the metal used. The current is controlled by hole injection at the metal-CdZnTe junction and there is consistent trend with the metal's work function possibly and it seems that metal to CdZnTe layer junction is ohmic contact.

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Transparent Phosphorus Doped ZnO Ohmic Contact to GaN Based LED

  • Lim, Jae-Hong;Park, Seong-Ju
    • 한국재료학회지
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    • 제19권8호
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    • pp.417-420
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    • 2009
  • This study develops a highly transparent ohmic contact using phosphorus doped ZnO with current spreading for p-GaN to increase the optical output power of nitride-based light-emitting diodes (LEDs). The phosphorus doped ZnO transparent ohmic contact layer was prepared by radio frequency magnetron sputtering with post-deposition annealing. The transmittance of the phosphorus doped ZnO exceeds 90% in the region of 440 nm to 500 nm. The specific contact resistance of the phosphorus doped ZnO on p-GaN was determined to be $7.82{\times}10^{-3}{\Omega}{\cdot}cm^2$ after annealing at $700^{\circ}C$. GaN LED chips with dimensions of $300\times300{\mu}m$ fabricated with the phosphorus doped ZnO transparent ohmic contact were developed and produced a 2.7 V increase in forward voltage under a nominal forward current of 20 mA compared to GaN LED with Ni/Au Ohmic contact. However, the output power increased by 25% at the injection current of 20 mA compared to GaN LED with the Ni/Au contact scheme.

Combinatorial studies on the work function characteristics for Nb or Zn doped indium-tin oxide electrodes

  • Heo, Gi-Seok;Kim, Sung-Dae;Park, Jong-Woon;Lee, Jong-Ho;Kim, Tae-Won
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.159-159
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    • 2008
  • Indium-tin oxides (ITO) films have been widely used as transparent electrodes for optoelectronic devices such as organic light emitting diodes (OLEDs), photovoltaics, touch screen devices, and flat-paneldisplay. In particular, to improve hole injection efficiency in OLEDs, transparent electrodes should have high work-function besides their transparency and low resistivity. Nevertheless, few studies have been made on engineering the work function of ITO for use as an efficient anode. In this study, the effects of a wide range of Nb or Zn doping rate on the changes in work functions of ITO anode were investigated. The Nb or Zn doped ITO films were fabricated on glass substrates using combinatorial sputtering system which yields a linear composition spread of Nb or Zn concentration in ITO films in a controlled manner by co-sputtering two targets of ITO and Nb2O5 or ITO and ZnO. We have also examined the resistivity, transmittance, and other structural properties of the Nb or Zn-doped ITO films. Furthermore, OLEDs employing Nb or Zn-doped ITO anodes were fabricated and the device performances were investigated concerned with the work function changes.

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흰쥐 조직에서의 카드뮴 결합 고분자량 단백질 [Cd-BP(II)]의 유도 (Induction of Cd-binding High Molecular Weight Protein [Cd-BP(II)] in Rat Tissues)

  • 천기정;김봉희
    • 약학회지
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    • 제43권5호
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    • pp.591-597
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    • 1999
  • The study was carried out on the biochemical characters of Cd-BP(II) after isolation and purification of the protein from the liver of rat ip injection with Cd. A continued study has been doing whether Cd-BP(II) could be induced by Cd or by the other metals such as Zn and Cu. Antisera were made against the antigen of Cd-BP(II) from New Zealand white rabbits. We carried out g-globulin purification, then Ouchterlony test and gel immunodiffusion test. Cd-BP(II) was also found in normal tissues of rat. It was induced up to a considerable level by Cd, whose induced level was higher than that Cu or Zn treatment. The level of induction by Cu or Zn pretreatment plus Cd treatment was lower than that by single treatment of Cu or Zn. Such a result was presumably related to the Cd toxicity.

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외부 환경조건에 따른 ZnO 피뢰기의 전기적 특성의 변화 (Changes in Electrical Properties of ZnO Surge Arresters According to Surrounding Conditions)

  • 이승주;이수봉;이복희
    • 조명전기설비학회논문지
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    • 제22권9호
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    • pp.62-68
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    • 2008
  • 이 논문은 ZnO 피뢰기의 외부환경 변화에 따른 전기적 특성을 기술하였다. 뇌임펄스전류에 의한 ZnO 피뢰기의 열화특성을 분석하기 위해 8/20[${\mu}s$], 2.5[kA]의 임펄스전류를 시료에 인가하였다. ZnO 피뢰기의 누설전류를 다양한 외부 온도와 주수 상태에서 상용 주파수 교류 전압을 인가하여 측정하였다. 그 결과 임펄스전류의 인가횟수와 외부 온도가 증가함에 따라 누설전류가 증가하였고, 누설전류의 비대칭성도 뚜렷하였다. 또한 주수 시험에서 ZnO 피뢰기의 외피를 통하여 흐르는 전류는 피뢰기 소자의 누설전류보다 크게 나타났다. 본 연구의 결과는 피뢰기의 감시시스템 성능과 신뢰성 향상의 요소로 적용할 수 있다.

ZnO 나노로드 배열에 의한 GaN기반 광다이오드의 광추출율 향상 (Improved Light Output of GaN-Based Light-Emitting Diodes with ZnO Nanorod Arrays)

  • 이삼동;김경국;박재철;김상우
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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    • pp.59-60
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    • 2008
  • GaN-based light-emitting diodes (LEDs) with ZnO nanorod arrays on a planar indium tin oxide (ITO) transparent electrode were demonstrated. ZnO nanorods were grown into aqueous solution at low temperature of $90^{\circ}C$. Under 20 mA current injection, the light output efficiency of the LED with ZnO nanorod arrays on ITO was remarkably increased by about 40 % of magnitude compared to the conventional LED with only planar ITO. The enhancement of light output by the ZnO nanorod arrays is due to the formation of side walls and a rough surface resulting in multiple photon scattering at the LED surface.

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Role of a ZnO buffer layer for the formation of epitaxial NiO films

  • 권용현;천성현;이주호;이정용;조형균
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2012년도 춘계학술발표대회
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    • pp.85-85
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    • 2012
  • NiO는 니켈 공공과 침입형 산소 이온에 의한 비화학적양론 특성 때문에 자발적으로 p-형 반도체 특성을 나타내는 것으로 알려져 있다. NiO는 3.7 eV 의 넓은 밴드갭을 가지고 있어 투명소자를 위한 hole injection layer 나 hole transport layer로 사용하기 위한 연구가 많이 이루어지고 있다. 또한, 안정적인 p-형 반도체 특성은 n-형 산화물 반도체와의 접합을 통해 복합소자의 구현이 용이하기 때문에, ZnO 등과의 접합을 통한 소자 구현이 가능하다.[1] 하지만, 기존의 많은 연구에서는 내부의 결함이 많이 존재하는 다결정 박막을 사용하였기 때문에, 전하의 이동에 제한이 발생해, 충분한 소자 특성을 나타내지 못하였다. 최근 Dutta의 연구에 의하면, 결정질 사파이어 기판위에 박막을 성장할 경우 [111] 방향으로 우선 배향성을 가진 NiO 박막을 얻을 수 있다고 알려져 있다.[2] 본 실험에서는 NiO 박막을 이용한 PN 접합소자 구현을 위해 사파이어 위에 p-NiO 박막을 에피택셜하게 성장한 후 구조적 특성을 분석하였으며, n-ZnO 박막을 그 위에 성장하여 소자를 제작하였다. 그 결과 ZnO 또한 에피택셜한 성장을 하는 것을 확인할 수 있었다. 성장순서에 따른 PN 접합구조 특성을 확인하기 위해 사파이어 위에 ZnO 를 성장시킨 후 NiO 를 성장시킨 결과 NiO 박막의 우선성장 방향이 [100]으로 변하는 것을 확인할 수 있었다.

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FBAR 소자의 압전층으로 사용되는 ZnO 박막의 증착시 ALD틀 이용한 2-step 법 적용에 관한 연구 (ZnO thin films used in the piezoelectric layer of FBAR devices were deposited by 2-step methods using ALD equipment)

  • 이순범;박성현;이능헌;신영화
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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    • pp.1651-1652
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    • 2006
  • In this study, the 2-step methode by ALD equipment was used to improve the characteristics of ZnO thin films used in a piezoelectric layer when the FBAR devices of a SMR type are fabricated. The Height of formed buffer layer was $400{\AA}$ and ZnO thin film of $13600{\AA}$ was deposited by RF sputter on the buffer layer. When ZnO thin films are deposited, deposition conditions such as pressure, injection time of source and purge time were changed variously. The characteristics of piezoelectric layer such as a crystal orientation and micro-structure of deposited ZnO thin films were studied by SEM, AFM and XRD.

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신수(BL23) 택사약침이 Cisplatin으로 유발된 급성신부전 백서에 미치는 영향 (Effects of Alismatis Rhizoma Pharmacopuncture at BL23 on Cisplatin-Induced Acute Renal Failure in Rats)

  • 김명식;김재홍;윤대환;정현우;조명래
    • Korean Journal of Acupuncture
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    • 제36권1호
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    • pp.63-73
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    • 2019
  • Objectives : This study was designed to investigate the effects of Alismatis Rhizoma (AR) pharmacopuncture at BL23 on acute renal failure induced by cisplatin. Methods : The Sprague-Dawley rats were divided into Normal group (no injection of cisplatin and no treatment), Control group (cisplatin injection without treatment), Acu group (needling at BL23 after cisplatin injection), AR-PA1 group (treated with $0.3571mg/kg/20{\mu}l$ of AR pharmacopuncture at BL23 after cisplatin injection), and AR-PA2 group (treated with $1.7855mg/kg/20{\mu}l$ of AR pharmacopuncture at BL23 after cisplatin injection). Each treatment was given once daily for 8 days. Changes in body weight, kidney weight, tumor necrosis factor-alpha ($TNF-{\alpha}$), interleukin-6 (IL-6), Cu-Zn superoxide dismutase (Cu-Zn SOD), glutathione peroxidase (GPx), serum blood urea nitrogen (serum BUN), and serum creatinine were observed. Results : Body weight was significantly increased in AR-PA1 on $4^{th}$ and $6^{th}$ days and AR-PA2 on $2^{nd}$ day. $TNF-{\alpha}$ was significantly decreased in Acu, AR-PA1 and AR-PA2 groups. Cu-Zn SOD was significantly increased in AR-PA2 group. GPx was significantly increased in AR-PA1 and AR-PA2 groups. But kidney weight, IL-6, serum BUN and serum creatinine were not significantly changed in any groups compared to control group. Conclusions : In acute renal failure induced by cisplatin, AR pharmacopuncture has a mitigating effect on the inflammatory reaction related to the increase of $TNF-{\alpha}$ in the kidney tissue and a protective effect on the oxidative stress of the kidney tissue. However it is unlikely to restore the glomerular function or inhibit the renal swelling.