• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.272-275
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• 2009

A new green phosphor, ($Mg_{1-x-yZnx)$)$Al_2O_4:Mn^{2+}{_y}$ (0 x 0.6, 0.001 y 0.01), was synthesized by a flux-assisted solid reaction and its vacuum ultraviolet (VUV) excitation and emission characteristics were examined in this study. The chromaticity and peak intensity of the $(Mg_{0.79}Zn_{0.2})Al_2O_4:Mn^{2+}{_{0.01}}$ (x = 0.177, y = 0.745) phosphor were found to be more desirable than that of $Zn_2SiO_4:Mn^{2+}$ (x = 0.216, y = 0.72) phosphor as a green primary color.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.359-359
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• 2009

투명전도 산화막 재료로 널리 사용되고 있는 ITO는 전기적 및 광학적 특성이 우수한 장점이 있으나, ITO의 주 재료인 인듐은 매장량이 적어서 가격이 고가인 단점이 있어 대체 재료의 개발이 시급한 상황이다. ITO 대체 TCO로 가장 유력한 후보인 Al doped ZnO(AZO)는 가시광을 투과하는 성질을 가지고 있고, 저온 공정이 가능하다는 장점뿐만 아니라 수소 분위기의 안정성 및 가격이 싸다는 장점이 있다. 본 연구에서는 양이온 금속원소(Al)과 음이온 할로겐 원소(F) 및 수소(H)를 co-doping한 ZnO 박막을 rf 마그네트론 스퍼터를 이용하여 증착한 뒤 도핑량과 진공중에서의 열처리에 따른 전기적 및 광학적 특성에 대해 고찰하였다. Al과 H를 co-doping한 ZnO의 박막의 경우 Al의 농도가 낮은 TCO박막이 전기적 특서에서 더 큰 향상을 보였으며, 동일한 F 함량에서는 H 함량이 늘어날수록 캐리어의 증가해 TCO박막의 전기적 특성이 향상되는 것으로 나타났다. 그러나 진공중의 열처리에 따른 F와 H의 거동은 반대로 나타났다. 이 연구를 통해서 $36.2cm^2$/Vs의 높은 홀 이동도와 $2.9{\times}10^{-4}{\Omega}cm$의 낮은 비저항을 가지는 ZnO계 박막의 제조가 가능하였다.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3213-3217
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• 2012

Reactive adsorption desulfurization (RADS) experiments were conducted over a series of commercial metal oxide supports ($Al_2O_{3-}$, $SiO_{2-}$, $TiO_{2-}$ and $ZrO_{2-}$) supported Ni/ZnO adsorbents. The adsorbents were characterized by X-ray diffraction (XRD), temperature programmed reduction (TPR), and Fourier transform infrared spectroscopy (FTIR) in order to find out the influence of specific types of surface chemistry and structural characteristics on the sulfur adsorptive capacity. The desulfurization performance of all the studied adsorbents decreased in the following order: Ni/ZnO-$TiO_2$ > Ni/ZnO-$ZrO_2$ > Ni/ZnO-$SiO_2$ > Ni/ZnO-$Al_2O_3$. Ni/ZnO-$TiO_2$ shows the best performance and the three hour sulfur capacity can achieve 12.34 mg S/g adsorbent with a WHSV of $4h^{-1}$. Various characterization techniques suggest that weak interaction between active component and support component, high dispersion of NiO and ZnO, high reducibility and large total Lewis acidity of the adsorbents are important factors in achieving better RADS performance.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.4
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• pp.480-492
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• 1996

AZO (Aluminum doped Zinc Oxide) transparent conducting thin films were fabricated by reactive DC mangnetron sputtering method using zinc target containing 2 wt% of Al. Transition range with optimum transmittance and conductivity was obtained by contrlling partial pressure of reactive oxygen gas. Sputtering condition for this transition range could be kept stable by regulating the target voltage. According to XRD analysis, there was only one peak for (002) plane in AZO films and the films deposited in transition range.

• Journal of the Korean Solar Energy Society
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• v.39 no.1
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• pp.33-40
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• 2019

Al-doped ZnO (AZO) thin films were synthesized on Si(100) wafers via plasma enhanced metal organic chemical vapor deposition (PE-MOCVD) method using diethyl zinc (DEZ) and N-methylpyrrolidine alane (MPA) as precursors. Effects of Al/Zn mixing ratio, plasma power on the surface morphology, crystal structure, and electrical property were investigated with SEM, XRD and 4-point probe measurement respectively. Growth rate of the film decreased slightly with increasing the Al/Zn mixing ratio, however electrical property was enhanced and resistivity of the film decreased greatly about 2 orders from $9.5{\times}10^{-1}$ to $8.0{\times}10^{-3}{\Omega}cm$ when the Al/Zn mixing ratio varied from 0 to 9 mol%. XRD analysis showed that the grain size increased with increasing the Al/Zn mixing ratio. Growth rate and electrical property were enhanced in a mild plasma condition. Resistivity of AZO film decreased down to $7.0{\times}10^{-4}{\Omega}cm$ at an indirect plasma of 100 W condition which was enough value to use for the transparent conducting oxide (TCO) material.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.155-156
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• 2006

Single crystalline ZnO fims were successfully grown on r-plane sapphire substrate by plasma-assisted molecular beam epitaxy. Epitaxial relationship between the ZnO film and the-r-plane sapphire was determined to be [-1101]$Al_2O_3\;{\parallel}$ [0001]ZnO, [11-20]$Al_2O_3\;{\parallel}$ [-1100]ZnO based on the in-situ RHEED analysis and confirmed again by HRXRD measurements. Grown (11-20) ZnO films showed faceted structure along the <0001> direction and the RMS roughness was about 4 nm.

• Journal of the Korean Ceramic Society
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• v.34 no.5
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• pp.483-490
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• 1997

Al2O3/metal composites were fabricated by oxidation and reaction of molten Al-alloy into two types of commercial Al2O3-SiO2 fibrous insulation board. The growth rate, composition and microstructure of these materials were described. An AlZnMg(7075) alloy was selected as a parent alloy. Mixed polycrystalline fiber and glass phase fiber were used as a filler. The growth surface of an alloy was covered with and without SiO2. SiO2 powder was employed as a surface dopant to aid initial oxidation of Al-alloy. Al-alloy, SiO2, fiber block and growth inhibitor CaSiO3 were packed sequentially in a alumina crucible and oxidized in air at temperature range 90$0^{\circ}C$ to 120$0^{\circ}C$. The growth rate of composite layer was calculated by measuring the mass increasement(g) per unit surface($\textrm{cm}^2$). XRD and optical microscope were used to investigate the composition and phase of composites. The composite grown at 120$0^{\circ}C$ and with SiO2 dopant showed rapid growth rate. The growth behavior differed a little depending on the types of fiber used. The composites consist of $\alpha$-Al2O3, Al, Si and pore. The composite grown at 100$0^{\circ}C$ exhibited better microstructure compared to that grown at 120$0^{\circ}C$.

• Journal of the Korea Institute of Military Science and Technology
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• v.15 no.4
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• pp.502-506
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• 2012

In order to find the structural characteristics of the thin films of group II-VI semiconductor compounds compared with those of powder materials, films were made of 4 powders of ZnS, CdS, CdSe, and CdTe(Aldrich), each with 99.99 % purity. For the ZnS/CdS multi-layers, the ZnS layer was coated over the CdS layer on an $AlO_x$ membrane, which served as a protective layer within a vacuum at the average speed of 1 ${\AA}$/sec. After studying the structures of the group II-VI semiconductor thin films by using X-ray spectroscopy, we found that the ZnS, ZnS/CdS, CdS, and CdSe films were hexagonal and exhibited some degree of preferred orientation. Also, the particles of the thin films of II-VI semiconductor compounds proved to be more homogeneous in size compared to those of the powder materials. These results were further verified through scanning electron microscopy(SEM), EDX analysis, and powder and thin film X-ray diffraction.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.924-927
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• 2003

Aluminium-doped ZnO (ZnO:Al) films were grown by atomic layer-controlled deposition on glass substrates at temperature of 200 $^{\circ}C$ using diethylzinc($Zn(C_{2}H_{2})_{2}$; DEtZn), water($H_{2}O$) and trimethylaluminium ($Al(CH_{3})_{3}$; TMA) as precursors. As the cycle ratio of TMA to DEZn(TMA/DEZn) increased, the resistivity of the films decreased and the roughness increased. In the case of TMA/DEZn pulse ratio of 1 to 10, the film had a resistivity of $9.7{\times}l0^{-4}{\Omega}{\cdot}cm$ and a roughness of 2.25nm(rms), while in the case of only DEZ injection the film had a resistivity of $3.5{\times}10^{-3}{\Omega}{\cdot}cm$ and a roughness of 1.07nm(rms)

• Journal of the Korean Ceramic Society
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• v.26 no.2
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• pp.187-194
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• 1989

Synthesis of spinel pigment on ZnO-Fe2O3 system. The object of this research is the synthesis of new spinel pigments on the basic of ZnO-Fe2O3 system which was substituted by ZnO-Fe2O3 by MgO-Al2O3. This research was progressed by measuring the X-ray diffraction and the reflectances of the substitued ZnO-Fe2O3 group. Which was obtained by sintering at the temperature of 1,00$0^{\circ}C$, 1,10$0^{\circ}C$, 1,20$0^{\circ}C$ and 1,25$0^{\circ}C$ and them by regrinding. In order to coloring test, here basic compositions of Barium glaze, Zinc glaze, Lime glaze, Lead glaze and Talc glaze used in this experiment are obtained from the ceramic work. Adding synthetic stains in these basic glazes with 3%, mixing and glazing on the specimen. The specimens was fired at 1,28$0^{\circ}C$ in reducing and oxidizing atmosphere in the gas kiln. The results of the research as follow. 1. Many kinds of spinel pigment was produced on ZnO-Fe2O3 system that is to say, not always only spinel. 2. Spinel peak was observed strongly on the ZnO-Fe2O3 system withsubstituting by MgO-Fe2O3 and MgO-Al2O3 group(the ratio of MgO, Al2O3 being increased, observed more strongly). 3. The most effective temperature ranges was 1,20$0^{\circ}C$~1,25$0^{\circ}C$. 4. The color of spinel pigments on this system was observed by "stable YR". 5. It was yellow red in oxidizing and green in reducing atmosphere on the coloring test.ring test.