• 한국세라믹학회지
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• 제38권4호
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• pp.337-342
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• 2001

PDP(Plasma Display Panel)용 녹색 형광체인 Zn$_2$SiO$_4$:Mn에 채-dopant로 Al을 첨가하여 졸-겔법으로 합성하였다. 졸-겔법으로 제조한 형광체는 기존의 고상 반응에 의해 합성된 경우보다 낮은 온도(1000-110$0^{\circ}C$)에서 Zn$_2$SiO$_4$단일상을 형성하였으며, 300-500nm의 비교적 균일한 입자를 얻을 수 있었다. 또한, co-dopant인 Al을 첨가함으로써 발광휘도를 향상시키고, 전광시간을 줄일 수 있었다. 한편, TEOS의 가수분해시 $H_2O$/TEOS 비율을 조절하여 발광의 최적 조건을 조사하였다.

• Transactions on Electrical and Electronic Materials
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• 제4권3호
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• pp.15-18
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• 2003

Aluminum oxide ($Al_2O_3$) materials were coated conformally on ZnO nanorods by atomic layer deposition (ALD). The ZnO nanorods were first synthesized on a Si(100) substrate from ball-milled ZnO powders by a thermal evaporation procedure. $Al_2O_3$ films were then deposited on these ZnO nanorods by ALD at a substrate temperature of $300^{\circ}C$ using trimethylaluminum (TMA) and distilled water ($H_2O$). Transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) images of the deposited ZnO nanorods revealed that amorphous $Al_2O_3$ cylindrical shells surround the ZnO nanorods. These TEM images illustrate that ALD has an excellent capability to coat any shape of nanorods conformally.

• 한국세라믹학회지
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• 제42권4호
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• pp.276-281
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• 2005

산소분위기, $750^{\circ}C$서 36 h 동안 하소함으로써 연소법에 의해 $LiNi_{1-y}M_{y}O_{2}(M=Zn^{2+},\;Al^{3+},\;and\;Ti^{4+},\;0.000\{\le}y{\le}0.100)$를 합성하였다. 각 시료에 대해 XRD 분석, FE-SEM 관찰, 싸이클 수에 따른 방전 용량의 변화 조사가 행해졌다. $LiNi_{0.99}M_{0.01}O_{2}$ (M=Zn, Al, and Ti) 조성이 여러 조성 중에서 대체로 우수한 전기화학적 특성을 나타내었다. 결정성과 cation mixing의 평가에서 Zn을 치환한 경우 결정성이 나쁘게 나타났고 Ti를 치환한 경우 cation mixing이 크게 나타났으며, Al을 치환한 경우 결정성이 좋고 cation mixing이 적게 나타났다. Al을 치환한 경우 싸이클 특성이 개선되었다.

• 한국재료학회지
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• 제25권11호
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• pp.598-601
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• 2015

Using reverse micelle processing, $ZnAl_2O_4$ nanopowders were synthesized from a mixed precursor(consisting of $Zn(NO_3)_2$ and $Al(NO_3)_3$). The $ZnAl_2O_4$ was prepared by mixing the aqueous solution at a molar ratio of Zn : Al = 1 : 2. The average size and distribution of the synthesized powders with heat treatment at $600^{\circ}C$ for 2 h were in the range of 10-20 nm and narrow, respectively. The average size of the synthesized powders increased with increasing water to surfactant molar ratio. The XRD diffraction patterns show that the phase of $ZnAl_2O_4$ was spinel(JCPDS No. 05-0669). The synthesized and calcined powders were characterized using a thermogravimetric - differential scanning calorimeter(TG-DSC), X-ray diffraction analysis (XRD), and high resolution transmission electron microscopy(HRTEM). The effects of the synthesis parameter, such as the molar ratio of water to surfactant, are discussed.

• Transactions on Electrical and Electronic Materials
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• 제9권2호
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• pp.67-72
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• 2008

Al-doped p-type ZnO thin films were fabricated by RF magnetron sputtering on n-Si (100) and homo-buffer layers in pure oxygen ambient. ZnO ceramic mixed with 2 wt% $Al_2O_3$ was selected as a sputtering target. XRD spectra show that the Al-doped ZnO thin films have ZnO crystal structure. Hall Effect experiments with Van der Pauw configuration show that p-type carrier concentrations are arranged from $1.66{\times}10^{16}$ to $4.04{\times}10^{18}\;cm^{-2}$, mobilities from 0.194 to $198\;cm^2V{-1}s^{-1}$ and resistivities from 0.0963 to $18.4\;{\Omega}cm$. FESEM cross section images of different parts of a p-type ZnO:Al thin film annealed at $800^{\circ}C$ show a compact structure. Measurement for same sample shows that density is $5.40\;cm^{-3}$ which is smaller than theoretically calculated value of $5.67\;cm^{-3}$. Photoluminescence (PL) spectra at 10 K show a shoulder peak of p-type ZnO film at about 3.117 eV which is ascribed to electron transition from donor level to acceptor level (DAP).

• Current Photovoltaic Research
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• 제3권1호
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• pp.32-38
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• 2015

CIGS solar cell consisted of various films. In this research, we investigated electrode materials in $Cu(In,Ga)Se_2$ (CIGS) cells, including Al-doped ZnO (ZnO:Al), intrinsic ZnO (i-ZnO), and Al films. The sputtered ZnO:Al film with a sputtering power at 200W showed the lowest series resistance and highest cell efficiency. The electrical resistivity of the 200-W sputtered ZnO:Al film was $5.2{\times}10^{-4}{\Omega}{\cdot}cm$ by the rapid thermal annealing at $200^{\circ}C$ for 1 min. The electrical resistivity of i-ZnO was not measurable due to its high resistance. But the optical transmittance was highest with less oxygen supply and high efficiency cell was achieved with $O_2/(Ar+O_2)$ ratio was 1% due to the increase of short-circuit current. No significant change in the cell performance by inserting a Ni layer between Al and ZnO:Al films was observed.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 제17회 워크샵 및 추계학술대회
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• pp.568-571
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• 2005

Highly transparent ZnO films with low resistivity for thin film solar cell applications were fabricated at low temperature by rf magnetron sputtering. Al-doped ZnO films were deposited on glass substrates at a substrate temperature of $200^{\circ}C$. electrical and optical properties of the ZnO:Al films were investigated in terms of the reparation conditions. The transmittance of the ZnO:Al films in the visible range is 90 %. The lowest resistivity of the ZnO:Al films is about $5.7\times10^{-4}$ $\Omega$ cm at the Al content of 2.5 wt% with the film thickness of 500 nm. After deposition, the smooth surface of ZnO:Al films were etched in diluted HCl (0.5%) to investigate the variation of electrical and surface morphology properties due to an textured surface.

• 한국진공학회지
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• 제22권3호
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• pp.119-125
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• 2013

In-line magnetron sputtering system을 사용하여 대면적($60{\times}60cm^2$) 소다라임 유리기판위에 투명전도성 ZnO(Al)와 ZnO(AlGa) 박막을 500 nm에서 1,450 nm까지 두께별로 증착하여 전기적, 광학적 특성을 연구하였다. XRD를 통해 c-축 방향성(002)을 가지고 성장된 것을 확인 하였다. Hall 특성 분석을 통해 이동도 및 캐리어 농도의 특성을 확인 하였으며, 그에 따른 ZnO(AlGa)의 비저항이 $9.03{\times}10^{-4}{\Omega}{\cdot}cm$에서 $7.83{\times}10^{-4}{\Omega}{\cdot}cm$으로 ZnO(Al) 보다 높게 나타났으며, 가시광선 영역에서 투과율은 87.6%에서 84.3%으로 나타났다. 따라서 ZnO(AlGa)는 전기적 특성이 우수하고 높은 투과율로 대면적용 투명전도성 재료로의 활용에 적합한 특성을 지닌 것을 확인 할 수 있었다.

• Transactions on Electrical and Electronic Materials
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• 제12권4호
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• pp.169-173
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• 2011

In this study, Al-N codoped p-type zinc oxide (ZnO) thin films were deposited on Si and homo-buffer layer templates in a mixture of $N_2$ and $O_2$ gas with ceramic ZnO:(2 wt% $Al_2O_3$) as a sputtering target using DC- magnetron sputtering. X-ray diffraction spectra of two-theta diffraction showed that all films have a predominant (002) peak of ZnO Wurtzite structure. As the $N_2$ fraction in the mixed $N_2$ and $O_2$ gases increased, field emission secondary electron microscopy revealed that the surface appearance of codoped films on Si varied from smooth to textured structure. The p-type ZnO thin films showed carrier concentration in the range of $1.5{\times}10^{15}-2.93{\times}10^{17}\;cm^{-3}$, resistivity in the range of 131.2-2.864 ${\Omega}cm$, and mobility in the range of $3.99-31.6\;cm^2V^{-1}s^{-1}$ respectively.

• Advances in Energy Research
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• 제2권2호
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• pp.97-104
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• 2014

A co-spray deposition technique has been developed to bypass a fundamental limitation in the conventional spray deposition technique, i.e., the deposition of metal oxides from incompatible precursors in the starting solution. With this technique, ZnO films codoped with F and Al have been successfully synthesized, in which F is incompatible with Al. Two starting solutions were prepared and co-sprayed through two separate spray heads. One solution contained only the F precursor, $NH_4F$. The second solution contained the Zn and Al precursors, $Zn(O_2CCH_3)_2$ and $AlCl_3$. The deposition was carried out at $500^{\circ}C$ on soda-lime glass in air. A minimum sheet resistance, $55.4{\Omega}/{\square}$, was obtained for Al and F codoped ZnO films after vacuum annealing at $400^{\circ}C$, which was lower than singly-doped ZnO with either Al or F. The transmittance for the codoped ZnO samples was above 90% in the visible range. This co-spray deposition technique provides a simple and cost-effective way to synthesize metal oxides from incompatible precursors with improved properties for photovoltaic applications.