• Title/Summary/Keyword: esca

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Characterization of the heat treatment of $AL_2O_3$ thin films by MOCVD (MOCVD법으로 제조한 $AL_2O_3$ 박막의 열처리에 의한 특성 평가)

  • 이상화;김종국;박병옥
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.7 no.2
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    • pp.216-223
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    • 1997
  • By using aluminum iso - propoxide($Al(OC_3H_7)_3$, AIP), $Al_2O_3$thin films were deposited on (100) single crystal silicon wafer by MOCVD method. The compositions of deposited films were analysed by electron spectroscopy for chemical analyse(ESCA). The morphology and thickness of the deposited films were characterized by scanning electron microscopy. The refractive index and C-V propertied were studied by using ellipsometery and HP4192A, respectively. From the results of ESCA and SEM analysis at low pressure, more uniform and stable stoichiometric film can be obtained compared with that of atmospheric pressure. For optical film usage, required refractive index can be obtained by heat treatment of deposited film. To improve C -V characteristics in NMOS device, it is requred to control OH-which is mobile charge in oxide, to form $SiO_2$ layer between $Al_2O_3$ and Si by heat treatment.

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Electrical and Chemical Properties of Mica/Epoxy Composite Materials as Affected by Short-Time Aging

  • Kim, Hee-Dong
    • KIEE International Transactions on Electrophysics and Applications
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    • v.3C no.2
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    • pp.59-65
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    • 2003
  • Electrical properties such as permittivity and tan$\delta$ of unaged (control) and aged (72 h at 18$0^{\circ}C$) mica/epoxy composites of 130 ${\mu}{\textrm}{m}$ thickness were measured and their surface conditions were characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR), electron spectroscopy for chemical analysis (ESCA), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Both permittivity and tan6 of control specimens were higher than those of short-time aged specimens. FTIR results show a new peak at 1710 $cm^{-1}$ / for short-time aged specimens, originating from carbonyl group formed by the oxidation reaction during the aging process. ESCA results show that the binding energy at 532.9 eV representing the singlet state of oxygen ( $O_{1s}$) decreases by 13.7%, whereas that at 534.6 eV increases by 13.7%. Glass transition temperatures of control and short-time aged specimens are observed to be 95.4$^{\circ}C$ and 113.4$^{\circ}C$, which increase with the increase of aging time. TGA results indicate that the control specimens contain a smaller amount of volatile components than the short-time aged specimens.s.

Plasma Surface Modification of Polystyrene Foam for Recycling 1. Hydrophilic Thin Film Deposition from Acrylamide (Polystyrene Foam의 재활용을 위한 플라즈마 표면개질 1. 아크릴아미드에 의한 친수성 박막생성)

  • Seo, Eun-Deock
    • Polymer(Korea)
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    • v.32 no.5
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    • pp.497-500
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    • 2008
  • Polystyrene foam (styrofoam) was treated with low-temperature oxygen plasma by means of immobilization and grafting techniques in order to modify its hydrophobic surface property to hydrophilic one using hydrophilic monomers of acrylic acid and acrylamide, and its surface chemical structure, morphology, and hydrophilicity were examined by ESCA, field emission scanning electron microscope (FESEM), and contactangle meter. The experimental evidences, such as the increases of O/C and N/C ratios in ESCA spectrum, thin film deposition, decrease in contact-angle, strongly suggested that the plasma treatments were useful methods for the preparation of hydrophilic surface. Contact angle diminished drastically from $84^{\circ}$ to $18{\sim}19^{\circ}$. Acrylamide, compared to acrylic acid, appeared to play a decisive role, and to be more powerful agent for improving its surface hydrophilicity.

Effects of the Oxygen Flow and Annealing on the Characteristics of $WO_3$ Film ($WO_3$막의 특성에 미치는 산소가스 유량 및 열처리 효과)

  • Rhie, Dong-Hee;Choi, Bok-Gil;Choi, W.S.;Moon, B.M.;Sung, Youg-Kwon
    • Proceedings of the KIEE Conference
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    • 1999.07d
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    • pp.1508-1510
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    • 1999
  • 스퍼터 퇴적 $WO_3$ 박막에 대해 열처리에 따른 전기적특성 및 구조적특성을 각각 4탐침법 및 AFM 관측에 의해 조사해 보고, 또한 스퍼터링시의 산소가스 유량비에 따른 $WO_3$ 박막의 막질을 ESCA에 의해 평가하였다 실험 결과 열처리에 의해 $WO_3$ 박막 표면의 평균거칠기가 $2.45\AA$에서 $152\AA$으로 크게 증가함을 알 수 있었다 또한 스퍼터시 산소유량비에 따른 효과를 ESCA로 관측한 결과, 열처리전에는 주피크가 34eV에서 나타남에 비해 열처리 후에는 36eV전후에서 나타났다.

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Bathochromic Finish of Dyed Fabrics by Low-Temperature Plasma and Sputter Etching Treatment (저온 플라즈마 및 Sputter Etching 처리에 의한 염색직물의 심색화 가공)

  • Pak, Pyong Ki;Lee, Mun Cheul;Park, Geon Yong
    • Textile Coloration and Finishing
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    • v.8 no.2
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    • pp.56-63
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    • 1996
  • Low-temperature plasma treatment or sputter etching is of interest as one of the techniques to modify polymer surface. In this study, poly(ethylene terephthalate)(PET), nylon 6 and cotton fabrics dyed three black dyes were subjected to low-temperature argon plasma and also sputter etching. In relation to bathochromic effect, the surface characteristics of the treated fabrics and films were investigated by means of critical surface tension, SEM and ESCA measurement. The depth of shade of fabrics more increased by the sputter etching technique than argon plasma treatment. Many microcraters on the fiber surface formed by the sputter etching resulted in increase of surface area of the fiber and wettability, but the hydrophobic group was increased by the results of ESCA analysis. In particular the change in reflective index of the fibers was much more effective than the chemical composition of the fiber surface on increasing of the depth of shade.

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Photografting of PET Fabrics with Vinyl Pyrrolidone and Acryloyl Morpholine Monomers

  • Huang, Weiwei;Jang, Jin-Ho
    • Textile Coloration and Finishing
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    • v.20 no.5
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    • pp.28-34
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    • 2008
  • PET fabrics were photografted under continuous UV irradiation with vinyl pyrrolidone (VP) and acryloylmorpholine(ACMO) as monomers and benzophenone as a hydrogen-abstractable photoinitiator. ACMO can be grafted onto the PET fabrics more efficiently than VP. The grafted PET surfaces were characterized by ATR, ESCA, SEM and zeta potential measurement. ATR and ESCA analysis indicated significant alterations on chemical structure and atomic composition on the surface of the grafted fabrics, where nitrogen content increased with increasing grafting yield. SEM images showed that the fabric surface was covered with the grafted polymers. The zeta potentials and the water wettability of the grafted PET increased with grafting. Also the photografted fabrics showed an increased dyeablity to reactive dyes and increased affinity to various iodine species which imparted anti-bacterial properties.