• Applied Chemistry for Engineering
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• v.18 no.6
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• pp.552-556
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• 2007

In this study, noble metals (Pd, Ru, Ir) were supported to $TiO_2$ catalyst. In order to distribute metals uniformly, $H_2O-H_2$ pretreatment technique was used. Xylene, toluene, and MEK were used as reactants. The monometallic or bimetallic catalysts were prepared by the excess wetness impregnation method and were characterized by XRD, and XPS analysis. Pd-Ru, Pd-Ir bimetallic catalysts had multipoint active sites which improved the range of Pd metal state. Bimetallic catalysts had a higher conversion of VOCs than that of monometallic one. The effect of $H_2O-H_2$ pretreatment technique was the enhancement of uniform distribution of Pd particles and promotion of catalytic efficiency. In this study, addition of Ru and Ir metals to Pd promoted oxidation conversion of VOCs. In addition, $H_2O-H_2$ pretreatment promoted removal efficiency of VOCs on the $TiO_2$ support.

• 한국전자현미경학회:학술대회논문집
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• 1997.11a
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• pp.41-42
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• 1997

• Journal of the Korean Vacuum Society
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• v.11 no.1
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• pp.35-42
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• 2002

We fabricate thermally stable and low resistance Ru ohmic contacts to $n-ZnO:Al(3\times10^{18}\textrm{cm}^{-3})$, grown by specially designed dual target sputtering system. It is shown that the as-deposited Ru contact produces a specific contact resistance of $2.1{\times}10^{-3}{\Omega}\textrm{cm}^2$. Annealing of the Ru contacts leads to the improvement of current-voltage characteristics. For example, annealing of the contact at $700^{\circ}C$ for 1 min produces a contact resistance of $3.2{\times}10^{-5}}{\Omega}\textrm{cm}^2$. furthermore, the metallisation scheme is found to be thermally stable: the surface of the contact is fairly smooth with a rms roughness of 1.4 nm upon annealing at $700^{\circ}C$. These results strongly indicate that the Ru contact represents a suitable metallisation scheme for fabrication of high-performance ZnO-based optical devices and high-temperature devices. In addition, possible mechanisms are suggested to describe the annealing temperature dependence of the specific contact resistance.

• Journal of the Korean Vacuum Society
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• v.5 no.1
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• pp.67-72
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• 1996

$RU_{1-x}Ir_xO_2$ films were deposited on the quartz substrate by a spray pyrolysis method. The x-ray diffraction patterns showed that the structure of the $RU_{1-x}Ir_xO_2$ film was tetragonal and the lattice constant $a_o$ and $c_o$ were increased from 4.495 A to 4.058 A and from 3.092A to 3.156 A, respectively as the Ir composition varied from 0.0 to 1.0. The $RU_{1-x}Ir_xO_2$ film was metallic and the resistivity of the samples was increased from $7{\times}10^{-5}{\Omega}\textrm{cm}$ to $48{\times}10^{-5}{\Omega}\textrm{cm}$ with increasing the Ir x. The surface of the sample was slightly roughed, the grain size and the grain boundary width were increased as the Ir composition varied from 0.0 to 1.0.

• Journal of the Korean Chemical Society
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• v.64 no.1
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• pp.49-53
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• 2020

• 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.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.296-298
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• 2005

Hydrogen generation by the hydrolysis of aqueous sodium borohydride $(NaBH_4)$ solutions was studied using IRA-400 anion resin dispersed Pt. Ru catalysts and Lithium Cobalt oxide $(LiCoO_2)$ supported Pt, Ru and PtRu catalysts. The performance of the $LiCoO_2$ supported catalysts is better than the ion exchange resin dispersed catalysts. There is a marked concentration dependence on the performance of the $LiCoO_2$ supported catalysts and the hydrogen generation rate goes down if the borohydride concentration is increased beyond $10\%$. The efficiency of PtRu- $LiCoO_2$ is almost double that of either Ru-$LiCoO_2$ or Pt-$LiCoO_2$ for $NaBH_4$ concentrations up to $10\%$.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1986-1988
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• 1999

Ferroelectric lead zirconate titanate(PZT) thin films were prepared on various bottom electrodes by rf magnetron sputtering methode. The structural phase and surface morphology of the PZT thin films were largely affected by the bottom electrodes. P-E curves of PZT thin films deposited on Pt. $RuO_2$ and Ru/$RuO_2$ bottom electrode showed typical P-E hysteresis loop. The measure values of $P_r,\;E_c$ of the Ru/PZT/Ru/$RuO_2$ capacitor were $16.9{\mu}C/Cm^2$, 140kV/ cm, respectively. The Ru/PZT/Ru/$RuO_2$ capacitors were fatigue free uP to nearly $10^9$ switching cycle but Pt/PZT/Pt capacitor showed 34% degradation uP to $10^9$ switching cycle.

• Analytical Science and Technology
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• v.11 no.5
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• pp.347-352
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• 1998

A study was carried out on the elelctrochemical characteristics of chemically modified electrodes (CMEs) by cyclic voltammetry. Fabrication of CMEs was made by coating with mixed valence (mv) inorganic-metal polymeric films on the glassy carbon electrode surface by potential cycling. Anodic oxidation behavior of methanol and L-ascorbic acid was studied by using CMEs working electrode. Deposition of films such as mv ruthenium oxo/ruthenium cyanide film (mv Ru-O/CN-Ru), mv ruthenium oxo/ferrocyanide film (mv Ru-O/$Fe(CN)_6$), and mv ruthenium oxo/ruthenium cyanide/Rhodium film (mv Ru-O/CN-Ru/Rh) was obtained to coat by scan rate of 50 mV/sec within the specified potential range (-0.5V ~ +1.2V). Film thickness was controlled by the repeat of the potential cycling. Anodic oxidation behavior of methanol was as follow. Calibration graph by using mv Ru-O/CN-Ru film showed linearly from 10 mM to 80 mM MeOH with slope factor of $-7.552{\mu}A/cm^2$. Although slope factor by using mv Ru-O/$Fe(CN)_6$ film was $-5.13{\mu}A/cm^2$, yet linear range of calibration graph could be extended from 10 mM to 100 mM MeOH. Anodic oxidation behavior of L-ascorbic acid was studied by mv Ru-O/CN-Ru film on the glassy carbon electrode and the glassy carbon electrode with Rh film, Glassy carbon electrode modified with Ru polymeric film was showed better sensitivity than the Rh-glassy carbon modified electrode (mv Ru-O/CN-Ru/Rh). Calibration graph was linear from 0.1 mM to 5 mM L-ascorbic acid by using glassy carbon electrode modified with Ru polymeric film. Solpe factor and relative coefficient are $-84.78{\mu}A/mM$ and 0.998, respectively.

• Applied Chemistry for Engineering
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• v.21 no.1
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• pp.81-86
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• 2010

On adsorbing carbon monoxide (CO) on the silica supported ruthenium/iron alloy ($Ru/Fe-SiO_2$) samples above mole ratio 9/1 of Ru/Fe five bands ($2138.7{\sim}2142.5cm^{-1}$, $2067.3{\sim}2073.1cm^{-1}$, $1976.7{\sim}2017.2cm^{-1}$, $1737.9{\sim}1799.3cm^{-1}$, $1625.7cm^{-1}$) were observed, and in $Ru/Fe-SiO_2$ samples below mole ratio 8/2 of Ru/Fe two bands ($1934.0{\sim}1990.2cm^{-1}$, $1625.7cm^{-1}$) were observed. The $2138.7{\sim}2142.5cm^{-1}$ bands, the $2067.3{\sim}2073.1cm^{-1}$ bands, and the $1988.3{\sim}2030.7cm^{-1}$ bands may be ascribed to stretching vibrations of CO molecules lineally bonded to the Ru atoms on supported Ru/Fe cluster surface, the $1737.9{\sim}1799.3cm^{-1}$ bands to stretching vibrations of CO molecules bridge bonded to the Ru atoms on supported Ru/Fe cluster surface or to stretching vibrations of CO molecules bonded to the Ru atoms on high Miller index planes, and the $1934.0{\sim}1990.2cm^{-1}$ bands to stretching vibrations of CO molecules lineally bonded to the Fe atoms on supported Ru/Fe cluster surface. The absorbances of the $1934.0{\sim}1990.2cm^{-1}$ bands in $Ru/Fe-SiO_2$ samples gradually increased with the increases of Ru/Fe mole ratio below the ratio of 8/2. This phenomena may be ascribed to the increases of Fe concentration of surface compared with the one of the sample and to the increases of surface area of supported Ru/Fe cluster according as increase of Ru/Fe mole ratio below the ratio of 8/2 compared with the $Fe-SiO_2$ sample.