• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1333-1334
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• 2007

Al thin film was the most popular electrode in semiconductor and flat panel display world, because of its electrical conductivity, selectivity and easy to apply to thin film. However, Al thin films were not good to use on the bottom electrode about the crystalline growth of inorganic compound materials such as ZnO, AlN and GaN, because of its surface roughness and melting points. In this paper, we investigated Ar plasma surface treatment of Al thin film to enhance the surface roughness and electrical conductivity using the reactive ion etching system. Several process conditions such as RF power, working pressure and process time were controlled. In results, the surface roughness showed $15.53\;{\AA}$ when RF power was 100 W, working pressure was 50 mTorr and process time was 10 min. Also, we tried to deposit ZnO thin films on the each Al thin films, the upper conditions showed the best crystalline characteristics by x-ray diffraction.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.187-187
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• 2010

In this study, we investigated the effect of electrodes on resistance switching of TaOx film. Pt, Ni, TiN, Ti and Al metal electrodes having the different oxidation degree were deposited on TaOx/Pt stack. Unipolar resistance switching behavior in Pt or Ni/TaOx/Pt MIM stacks was investigated, but bipolar resistance switching behavior in TiN, Ti or Al /TaOx/Pt MIM stacks was shown. We investigated that the voltage dependence of capacitance was decreased with higher oxidation degree of metal electrodes. Through the C-V results, we expected that linearity ($\alpha$) and quadratic ($\beta$) coefficient was reduced with an increase of interface layer between top electrode and Tantalum oxide. Transmission Electron Microscope (TEM) images depicted the thickness of interface layer formed with different oxidation degree of top electrode. Unipolar resistance switching behavior shown in lower oxidation degree of top electrode was expected to be generated by the formation of the conducting path in TaOx film. But redox reaction in interface between top electrode and Tantalum oxide may play an important role on bipolar resistance switching behavior exhibited in higher oxidation degree of top electrode. We expected that the resistance switching characteristics were determined by oxidation degree of metal electrodes.

• Proceedings of the Materials Research Society of Korea Conference
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• 1992.05b
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• pp.24-25
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• 1992

• 한국전기화학회:학술대회논문집
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• 2004.04a
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• pp.13-13
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• 2004

• Journal of the Microelectronics and Packaging Society
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• v.12 no.3 s.36
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• pp.235-241
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• 2005

Incorporation of solid electrodes frequently involves plasma-based processing. The effect of plasma can influence the physical characteristics, depending on the magnitude in plasma. The undesired feature of plasma-induced damage should be prevented in characterizing the ultra-thin materials, such as ultra-thin films and organic monolayers. The current work at first proves the applicability of a liquid phase electrode in the electrical/dielectric properties through comparative work using Al and Hg on ultrathin $Al_2O_3$ films deposited through atomic layer deposition at low temperature: Two types of metals such as Aluminum (Al) and mercury (Hg) were used as electrodes in $Al_2O_3$ thin films in order to investigate the effect of electrode preparation on the current-voltage characteristics and impedance features as a function of thickness in $Al_2O_3$ film thickness. The success of Hg in $Al_2O_3$ thin films is applied to the AC and DC characterization of the organic monolayers obtained using the Langmuir-Blodgett method. From the DC current-voltage characteristics, the diode-like response is found to originate from the bulk response of the organic materials, evidenced by the fact and the capacitance is inversely related to the absolute thickness of organic layers.

• Korean Journal of Materials Research
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• v.2 no.2
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• pp.157-160
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• 1992

Unusual surface impurity levels of PREPed Ti-51at%Al powders were analyzed using Auger spectroscopy and they were compared with these obtained from bulk starting electrode. Oxygen and carbon contents were varied very much with particle size. Powder surfaces were believed to be mainly covered by a complex compound containing Ti, Al, O, and C. The decrease in contents of oxygen and carbon of powders were attributed to the certain refining reaction of transfer type DC Ar plasma during the powder production.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.143-144
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• 2005

Recently, MIM(metal-insulator-metal) capacitor is one of the essential device for DRAM device. In this thesis, $Al_2O_3$ thin film which has a relatively high dielectric constant was deposited by ALD(atomic layer deposition) using MPTMA and $H_2O$ source. Deposition temperature of $Al_2O_3$ thin film was $200^{\circ}C$ and its thickness was 300 ${\AA}$. $RuO_2$ bottom electrode was deposited by RF-magnetron sputtering using $RuO_2$ target. The physical characteristics of $Al_2O_3$ films were investigated by AES, TEM and Ellipsometry. Electrical characteristics were analyzed by C-V and I-V measurement.

• Journal of the Korean Magnetics Society
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• v.8 no.1
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• pp.27-33
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• 1998

We have investigated tunneling magnetoresistance (TMR) properties of Fe/$Al_2O_3$/Co magnetic trilayer junctions sputtered on single-crystal Si (001) substrates. $Al_2O_3$ layers with thicknesses of 50~200 $\AA$ were deposited directly on the bottom ferromagnetic layer by a reactive rf sputtering. For comparsion, we prepared Pt/$Al_2O_3$/Pt tunnel junctions whose current-voltage (I-V) characteristics measured at 300 K indicated that reactively sputtered $Al_2O_3$ is a particularly good material for thin insulating barriers and allows us to form pinhole-free tunnel barriers. The magnetic tunnel junctions exhibit changes of tunnel resistance of about 0.1% at 300 K with an applied magnetic field and it was found that most junctions with Co as a top electrode have rather good I-V and TMR characteristics compared to those with Fe as a electrode. These results were discussed in relation to interfacial on the basis of those for Pt/$Al_2O_3$/Pt.

• Korean Journal of Materials Research
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• v.25 no.1
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• pp.16-20
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• 2015

In this study, in order to improve the efficiency of n-type monocrystalline solar cells with an Alu-cell structure, we investigate the effect of the amount of Al paste in thin n-type monocrystalline wafers with thicknesses of $120{\mu}m$, $130{\mu}m$, $140{\mu}m$. Formation of the Al doped $p^+$ layer and wafer bowing occurred from the formation process of the Al back electrode was analyzed. Changing the amount of Al paste increased the thickness of the Al doped $p^+$ layer, and sheet resistivity decreased; however, wafer bowing increased due to the thermal expansion coefficient between the Al paste and the c-Si wafer. With the application of $5.34mg/cm^2$ of Al paste, wafer bowing in a thickness of $140{\mu}m$ reached a maximum of 2.9 mm and wafer bowing in a thickness of $120{\mu}m$ reached a maximum of 4 mm. The study's results suggest that when considering uniformity and thickness of an Al doped $p^+$ layer, sheet resistivity, and wafer bowing, the appropriate amount of Al paste for formation of the Al back electrode is $4.72mg/cm^2$ in a wafer with a thickness of $120{\mu}m$.

• Journal of environmental and Sanitary engineering
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• v.19 no.3 s.53
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• pp.31-39
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• 2004

In order to reduce the pollution load from the livestock farms and to improve the water quality of the effluent in livestock wastewater, the electrolysis system is introduced. For the selection of optimal electrode, various combination of electrodes such as carbon, Al and Fe were examined. In this study, electrode material, electrolyte concentration, electrode distance, current density, and pH value were found to have significant effect on both pollutant removal efficiency and current efficiency in electrochemical oxidation process. After electrolysis for 90 min with carbon/Al, it was observed that COD, T-N, T-P and $NH_4^+-N$ of livestock waste-water were removed with $80\%,\;61\%,\;81\%\;and\;87\%$, respectively.