• 한국세라믹학회지
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• 제25권4호
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• pp.341-348
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• 1988

Thin films of tin-oxide were prepared by chemical vapor deposition technique using the direct of SnCl4. Resistivity and carrier concentration of deposited SnO2 thin film were measured by 4-point probe method and Hall effect measurement. The results showed the remarkable dependence of electrical properties on the deposition temperature. As the deposition temperature increased, resistivity of deposited film initially decreased to a minimum value of ~10-3$\Omega$cm at 50$0^{\circ}C$, and then rapidly increased to ~10$\Omega$cm at $700^{\circ}C$. Electrical conductance of these films was measured in exposure to H2 gas. It was found that gas sensitivity was affected combination of film thickness and intrinsic resistivity of deposited film. Gas sensitivity increased with decrease of film thickness. Fairly high sensitivity to H2 gas was obtained for the film deposited at $700^{\circ}C$. Optimum operation temperature of sensing was 30$0^{\circ}C$ for H2 gas.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 봄 학술발표회 논문집
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• pp.663-668
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• 2000

In this study, the Atterberg limit and grain-size analysis were carried for the purpose of investigating the influence on drying and organic matter of Ulsan marine deposited clay. The results revealed that Atterberg limit was decreased and grain-size distribution was variable on drying. The presence of organic matter also influenced on the physical properties of the soils. The physical properties of marine deposited clay were variable on drying, so that we recommended grain-size analysis and Atterberg limit test were performed under the wet condition of the soils after sampling.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.487-490
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• 2008

Temperature programmed oxidation (TPO) is used to characterize coke species deposited on commercial nickel catalyst, C11-PR during propane pre-reforming. Propane pre-reforming performed under various condition, S/C from 1.5 to 2.5 and temperature from $350^{\circ}C$ to $450^{\circ}C$. There are three kinds of coke species detected by TPO: (i) reactive coke, (ii) coke deposited on metal site and (iii) coke deposited on acid support. Coke deposited on metal and support are minimized although reactive coke is generated at temperature of $400^{\circ}C$ and S/C of 2.0. Reactive coke is expected to remove easily below temperature of $200^{\circ}C$. Therefore, optimized pre-reforming condition for propane is $400^{\circ}C$ and S/C of 2.0.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 추계학술발표대회
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• pp.32.1-32.1
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• 2011

Ultra thin tantalum nitride (TaNx) films with various thicknesses (10 nm to 40 nm) have been deposited by rf magnetron sputtering technique on glass substrates. The as deposited films were systematically characterized by several analytical techniques such as X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, atomic force microscopy, UV-Vis-NIR double beam spectrophotometer and four point probe method. From the XRD results, the as deposited films are in amorphous nature, irrespective of the film thicknesses. The films composition was changed greatly with increasing the film thickness. SEM micrographs exhibited the densely pack microstructure, and homogeneous surface covered by small size grains at lower thickness deposited films. The surface roughness of the films was linearly increases with increasing the films thickness, consequently the transmittance decreased. The absorption edge was shifted towards higher wavelength as the film thickness increases.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.95.1-95.1
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• 2011

In this work, graphene was prepared by modified Hummers method and prepared graphene was applied to electrode materials for supercapacitor. In addition, to enhance the electrochemical performance of graphene, carbon black was deposited onto graphene via chemical reduction. The effect of the carbon black content incorporated on the electrochemical properties of the graphene-based electrodes was investigated. It was found that nano-scaled carbon black aggregates were deposited and dispersed onto the graphene by the chemical reduction of acid treated carbon black and graphite oxide. From the cyclic voltammograms, carbon black-deposited graphene (CB-GR) showed improved electrochemical performance, i.e., current density, quicker response, and better specific capacitance than that of pristine graphene. This indicates that the carbon black deposited onto graphene served as an conductive materials between graphene layers, leading to reducing the contact resistance of graphene and resulted in the increase of the charge transfer between graphene layers by bridge effect.

• Journal of Pharmaceutical Investigation
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• 제12권3호
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• pp.74-87
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• 1982

To evaluate the pharmaceutical aspects of solvent deposition method where drug is solvent deposited on the surface of excipients, a study has been made on dissolution characteristics of indomethacin solvent deposited on lactose and potato starch. In a solvent deposition system, the drug-to-excipient ratio and kind of excipient effect much on dissolution rates of indomethacin. The experimental results are as follows: 1) Lactose was shown to be superior to potato starch as excipients in indomethacin solvent deposited. 2) Total amount of indomethacin dissolved from solvent deposition systems at 30 minutes were enhanced about 5 to 23 times compared with that of pure indomethacin. 3) Increased dissotion amount of indomethacin from the solvent deposition systems were observed to be alike in the systems where the drug-to-excipient weight ratios were 1 : 5, 1 : 7 and 1 : 10.

• Journal of Korean Vacuum Science & Technology
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• 제3권2호
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• pp.130-133
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• 1999

Paraelectric ZrTiO4 thin films were synthesized on a Si(100) substrate using DC magnetron reactive sputtering. Films deposited above-400$^{\circ}C$ exhibited crystalline characteristics. The dielectric constants ($\varepsilon$) and dielectric losses (tan$\delta$) of as-deposited and annealed films were measured in the 1 MHz range using a Pt upper electrode and a phosphorous-doped si bottom electrode. Preliminary data showed that as the deposition temperature increased, the dielectric losses decreased while the dielectric constants did not change significantly. similar trends for dielectric losses were observed when the as-deposited samples were annealed at 800$^{\circ}C$. The reduction of dielectric losses at high-deposition temperatures and post annealing correlated well with the x-ray diffraction peak widths.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1514-1515
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• 1998

Diamond thin films were deposited on n-type (100) Si wafers from $H_2-CH_4$ gas mixture by rf PACVD. Prior to deposition, mechanical scratching was done to improve density of nucleation sites with diamond paste of 3${\mu}m$. The microstructure of deposited diamond thin films was studied by using the following conditions : discharge power of 500W, $H_2$ flow rate of 50sccm, reaction pressure of 20torr, and $CH_4/H_2$ ratio of 0.3$\sim$1%. The deposited diamond thin films showed that the crystallite was increased at the lower methane concentration. The deposited thin films were characterized by Scanning Electron Microscopy. Raman Spectroscopy and Fourier-Transform Infrared Spectroscopy.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1330-1332
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• 1998

Polycrystalline diamond films are deposited on a Si substrate by employing a 2.45 GHz $\mu$-wave plasma CVD system. Prior to depositing the diamond film, a DPR(diamond photo-resist) layer is coated to enhance the nucleation density. The growth rate of diamond films increases with the $\mu$-wave power and approaches to be about $1.5{\mu}m/hr$ at 1100 W. Structural properties of diamond films deposited are characterized from their SEM photographs, Raman spectra, and AFM surface images. Lager grain size, higher intensity of diamond peak, and smoother surface are observed for films deposited at a higher power. The possible mechanism on the diamond growth is also discussed to explain the experimental results.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.229-230
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• 2008

We have studied the structural and optical properties of ZnO thin film deposited on glass by RF magnetron sputtering as functions of working pressures. The grain sizes were decreased as the working pressures were increased. The average optical transmissions over all exceeded 80% for ZnO films deposited in 20, 25 and 300m torr working pressures. And the transmission spectra patterns were almost same. While the transmission spectra pattern of ZnO film deposited in 35nm torr was different with other spectra patterns obtained in 20, 25 and 30nm torr working pressures.