• 에너지공학
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• 제11권2호
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• pp.136-141
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• 2002

석탄가스화 복합발전용 고온건식 탈황제의 반응성을 개선하기 위하여 $Al_2$O$_3$를 지지체로사용한 ZnO/Al$_2$O$_3$ 탈황제를 제조하고 반응특성을 조사하였다. ZnO/Al$_2$O$_3$의 성분함량 및 소성온도에 따른 물리화학적 구조변화를 XRD로 관찰하였고 ZnO의 소결 및 열화로 인한 활성저하를 $Al_2$O$_3$의 함량과 소성온도를 변화시켜 개선할 수 있음을 탈황 및 재생반응실험을 통하여 확인하였다. 마지막으로 첨가제를 함유한 ZnO/Al$_2$O$_3$ 탈황제의 내구성실험에 의한 고온건식 탈황제로의 사용가능성을 실험적으로 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1301-1304
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• 1994

ZnO transparent conducting oxide thin films have been prepared by Pyrosol deposition method. The effect of the Al doping with varying Al/Zn mole ratio and the post-deposition heat treatment on the electrical resistivity and optical transmittance of the prepared films have been investigated. From the experimental results, the ZnO:Al thin films with resistivity as low as $3{\times}10^{-3}{\Omega}cm$ and transmittance as high as 80% can be obtained by Al doping. Also We have found the annealing of the as-deposited ZnO film in vacuum leads to a substantial reduction in resistivity without affecting the optical transmittance and crystallographic orientation. However, the annealing effect of ZnO:Al thin films is smaller than ZnO films with respect to reduction in resistivity.

• 한국전기전자재료학회논문지
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• 제22권4호
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• pp.318-322
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• 2009

In this paper, to establish growth technology of ZnO:Al thin films at low temperature applied to photoelectronic devices, ZnO:Al were prepared by RF magnetron sputtering on glass substrate at room temperature using different RF power with subsequent annealing process at different temperature in $H_2$ ambient. The resistivity of hydrogen-annealed ZnO:Al thin film at temperature of $300^{\circ}C$ was reduced to $8.32{\times}10^{-4}{\Omega}cm$ from $9.44{\times}10^{-4}{\Omega}cm$ which was optimal value for as-grown films. X-ray photoelectron spectroscopy(XPS) revealed that improved electrical properties are ascribed to desorption of the negatively charged oxygen species from the grain boundary surfaces by the hydrogen annealing process.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.262.2-262.2
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• 2013

ZnO는 광학적 및 전기적 성질의 여러 가지 장점 때문에 메모리, 나노발전기, 트랜지스터, 태양전지, 광탐지기 및 레이저와 같은 전자소자 및 광소자로 여러 분야에서 다양하게 사용되고 있다. Al이 도핑된 ZnO 나노결정체를 전기화학적 증착법을 이용하여 형성하고, 형성시간의 변화에 따른 구조적 및 광학적 성질을 관찰했다. ITO로 코팅된 유리 기판에 전기화학증착법을 이용해 Al 도핑된 ZnO를 성장시켰다. Sputtering, pulsed laser vapor deposition, 화학기상증착, atomic layer epitaxy, 전자빔증발법 등으로 Al 도핑된 ZnO 나노구조를 형성할 수 있지만, 본 연구에서는 간단한 공정과정, 저온증착, 고속, 저가의 특성 등으로 경제적인 면에서 효율적인 전기화학증착법을 이용했다. 반복실험을 통하여 Al의 도핑 농도는 Zn와 Al의 비율이 98:2이 되도록, ITO 양극과 Pt 음극의 전위차가 -2.25 V가 되도록 실험조건을 고정했고, 성장시간을 각각 1분, 5분, 10분으로 변화하였다. 주사전자현미경 사진을 보면 Al 도핑된 ZnO는 성장 시간이 증가함에 따라 나노구조의 직경이 커지는 것을 알 수 있다. 광루미네센스 측정 결과는 산소 공핍의 증가로 보이는 500~600 nm대의 파장에서 나타난 피크의 위치가 에너지가 큰 쪽으로 증가했다. 위 결과로부터 성장 시간에 따른 Al 도핑된 ZnO의 구조적 및 광학적 특성변화를 관찰했고, 이 연구 결과는 Al 도핑된 ZnO 나노구조 기반 전자소자 및 광소자에 응용 가능성을 보여주고 있다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.118-118
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• 2011

The Nano-Floating Gate Memory(NFGM) devices with ZnO:Cu thin film embedded in Al2O3 and AlOx-SAOL were fabricated and the electrical characteristics were evaluated. To further improve the scaling and to increase the program/erase speed, the high-k dielectric with a large barrier height such as Al2O3 can also act alternatively as a blocking layer for high-speed flash memory device application. The Al2O3 layer and AlOx-SAOL were deposited by MLD system and ZnO:Cu films were deposited by ALD system. The tunneling layer which is consisted of AlOx-SAOL were sequentially deposited at $100^{\circ}C$. The floating gate is consisted of ZnO films, which are doped with copper. The floating gate of ZnO:Cu films was used for charge trap. The same as tunneling layer, floating gate were sequentially deposited at $100^{\circ}C$. By using ALD process, we could control the proportion of Cu doping in charge trap layer and observe the memory characteristic of Cu doping ratio. Also, we could control and observe the memory property which is followed by tunneling layer thickness. The thickness of ZnO:Cu films was measured by Transmission Electron Microscopy. XPS analysis was performed to determine the composition of the ZnO:Cu film deposited by ALD process. A significant threshold voltage shift of fabricated floating gate memory devices was obtained due to the charging effects of ZnO:Cu films and the memory windows was about 13V. The feasibility of ZnO:Cu films deposited between Al2O3 and AlOx-SAOL for NFGM device application was also showed. We applied our ZnO:Cu memory to thin film transistor and evaluate the electrical property. The structure of our memory thin film transistor is consisted of all organic-inorganic hybrid structure. Then, we expect that our film could be applied to high-performance flexible device.----못찾겠음......

• 한국재료학회지
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• 제24권6호
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• pp.301-304
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• 2014

The effect of oxygen pressure on the synthesis of ZnO nanowires by means of melt-oxidation of an Al-Zn mixture was investigated. The samples were prepared in oxygen ambient for 1 h at $1,000^{\circ}C$ under oxygen pressure ranging from 0.5 to 100 Torr. ZnO nanowires were formed at oxygen pressures lower than 10 Torr. As the oxygen pressure increased from 0.5 to 10 Torr, the width of the nanowires increased, but their length decreased. The ZnO nanowires had a needle shape, which became gradually thinner toward the tip. X-ray diffraction patterns showed that the nanowires had a hexagonal wurtzite structure. However, ZnO nanowires were not observed when the oxygen pressure increased from 10 Torr to 100 Torr. In roomtemperature cathodeluminescence spectra of the ZnO nanowires, the intensity of ultra-violet emission at 380 nm increased with decreasing oxygen pressure, which indicated that the lower the oxygen pressure, the better the crystallinity of the ZnO nanowires.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.410-411
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• 2007

To investigate the ZnO LED which are interested in the next generation of short wavelength LEDs and Lasers, the ZnO thin films were deposited by RF magnetron sputtering system. The p-type ZnO thin film, fabricated by means of the ampoule-tube method, was used to make the ZnO p-n junction, and its characteristics was analyzed. The ampoule-tube method was used to make the p-type ZnO based on the As diffusion, and the hall measurement was used to confirm that the p-type is formed. the current-voltage characteristics of the ZnO p-n junction were measured to confirm the rectification characteristics of a typical p-n junction and the low leakage voltage characteristics. Analysis of ZnO LED V-I curve will provide a very useful technology for producing the UV ZnO LED and ZnO-based devices.

• 한국결정성장학회지
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• 제14권6호
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• pp.277-280
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• 2004

p형 ZnO 에피 박막을 사파이어 기판의 (0001)면 상에 RF-DC magnet co-sputtering 법으로 성장시켰다. 약 120nm두께의 단결정상 박막을 성공적으로 얻어내었다. p형 ZnO를 만들기 위해서 Al 금속 타켓을 이용하여 DC 스퍼터링으로 $400^{\circ}C$와 $600^{\circ}C$에서 ZnO를 rf magnetron sputtering으로 증착하고, 동시에 Al의 doping을 행하였으며, 성장된 박막의 결정성과 광특성에 대하여 고찰하였다.

• The Korean Journal of Ceramics
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• 제7권2호
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• pp.85-92
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• 2001

Thin films of ZnO and Al doped ZnO were prepared by rf magnetron sputter techniques. When the oxygen fraction in Ar-O$_2$ sputter gas was about 2.0%, the films exhibited the composition of Zn:O=1.05:1. The films prepared at 250 W contain larger grains than the films grown at 100 W. However, high deposition rate seems to deteriorates the crystallinity as well as Al-substitution, resulting in lower concentration of mobile electrons. The Al-doped ZnO films which were deposited at $500^{\circ}C$ show resistance of 1$\times$10$^-2$ Wcm; optical band gap of the films ranges from 3.25 to 3.40 eV. These electrical and optical features are related with microstructural as well as crystalline characteristics of the films.

• 조명전기설비학회논문지
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• 제20권7호
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• pp.6-13
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• 2006

각 종 전자 디바이스의 투명전도막으로 많이 사용되는 ITO 및 ZnO:Al 박막을 스퍼터링법에 의해 제작하였다. 가스압력 및 기판온도 등의 최적조건하에서 제작된 ITO 및 ZnO:Al 박막은 각각 $1.67{\times}10^{-3}[{\Omega}-cm]$ 및 $2.2{\times}10^{-3}[{\Omega}-cm]$의 비저항율과 89.61[%] 및 90.88[%]의 가시광 영역에서의 광투과율을 나타내었다. ZnO:Al과 ITO 투명전극을 이용하여 5인치의 PDP 셀을 동일한 제조조건하에서 제작하였다. ZnO:Al의 경우 Ne(base)-Xe(8%)의 가스 혼합비, 그리고 400[Torr]의 압력조건에서 가장 잘 동작되었으며, $200{\sim}300$[V]의 인가전압 범위에서 $836[cd/m^2]$의 평균휘도를 나타내었다. 고휘도 및 저 소비전력특성을 위한 중요한 파라메타인 광효율은 전원 주파수가 $10{\sim}50[Khz]$의 범위에서 $1.2{\sim}1.6[lm/W]$정도를 나타내었으며, ITO의 경우 휘도 및 광 발생 효율은 약 10[%]정도 상승하였다.