• 제목/요약/키워드: Film cracks

검색결과 169건 처리시간 0.026초

졸-겔 방법으로 제조한 TiN 박막에 관한 연구 (A Study on the TiN Thin Film by Sol-Gel Method)

  • 김왕섭;선효님;김경용;김병호
    • 한국세라믹학회지
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    • 제29권4호
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    • pp.328-334
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    • 1992
  • TiO2 sols were prepared by hydrolysis and polymerization of titanium tetra-isopropoxide (TTIP) in the presence of diethanolamine (DEA). The optimal mole ratio of water to TTIP is 2 and the concentration of the TiO2 sol 0.7 M. Golden TiN films without cracks were obtained by dipping Si(110) wafers into the TiO2 sol and followed by nitridation in NH3 at 1100$^{\circ}C$ for 5 h. The TiN films were studied by an optical microscope, DTA, TGA and X-ray analysis.

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강판의 열간윤활압연특성 연구I (열간압연마모 시험기의 개발과 시험) (Development of Hot Rolling Wear Simulator and Roll Wear)

  • 김철희
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1996년도 제24회 춘계학술대회
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    • pp.126-132
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    • 1996
  • A laboratory scale hot strip rolling wear simulator(HRWS) was developed for the purpose of investigating the tribological phenomena occurred in production hot strip rolling mills. The HRWS' main parts are the electric heater, the mechanical descaler, tandem type 2-4Hi rolling mill stands, the cooling chamber, the tension controller and coiler. By simulating the tribelogical phenomena in rolling process at laboratory, wear patterns, cracks, cat-ear wear, black film, effect of hot rolling oil lubrication, etc. were reproduced, and discussed on the performace of simulator.

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폴리페닐카보실란을 이용한 SiOC가 코팅된 스테인리스스틸 제조 및 이의 내부식성 특징 (SiOC Coating on Stainless Steel Using Polyphenylcarbosilane, and Its Anti-corrosion Properties)

  • 김종일;이윤주;김수룡;김영희;김정일;우창현;최두진
    • 한국재료학회지
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    • 제21권1호
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    • pp.8-14
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    • 2011
  • To improve the chemical stability of metal, the ceramic coatings on metallic materials have attracted interest from many researchers due to the chemical inertness of ceramic materials. To endure strong acids, SiOC coating on metal substrate was carried out by dip coating method using 20wt% polyphenylcarbosilane solution; SiC powder was added to the solution at 10wt% and 15wt% to improve the mechanical properties and to prevent cracks of the film. Thermal oxidation as a curing step was carried out at $200^{\circ}C$ for crosslinking of the polyphenylcarbosilane, and the coating samples were pyrolysized at $800^{\circ}C$ under argon to convert the polyphenylcarbosilane to SiOC film. The thicknesses of the SiOC coating films were $2.36{\mu}m$ and $3.16{\mu}m$. The quantities of each element were measured as $SiO_{1.07}C_{6.33}$ by EPMA, and it can be confirmed that the SiOC film from polyphenylcarbosilane was formed in a manner that was carbon rich. The hardness of the SiOC film was found to be 3.2Gpa through nanoindentor measurement. No defect including cracks appeared in the SiOC film. The weight loss of the SiOC coated stainless steel was within 2% after soaking in 10% HCl solution at $80^{\circ}C$ for one week. From these results, SiOC coating shows good potential for application to protect against severe chemical corrosion of stainless steel.

졸-겔 방법으로 제조한 ZnO 쇼트키 다이오드의 특성 연구 (Schottky diode characteristics of a sol-gel driven ZnO)

  • 한광준;강광선;김재환
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1733-1736
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    • 2008
  • ZnO thin films with preferred orientation along the (0 0 2) plane were fabricated by a sol-gel method. The effects of the annealing temperature, time, and thickness were studied by investigating UV-visible spectra, FT-IR spectra, and XRD of ZnO films. The films were dried and annealed ed at $100^{\circ}C,\;200^{\circ}C$, and $300^{\circ}C$ for 1hr, 2hrs, and 3hrs, respectively. The film showed the preferred (0 0 2) orientation and high transmittance near 90% in the visible range. Also, SEM images of the films exhibited very smooth surfaces without holes and cracks. Schottky diodes were fabricated by using ZnO sol-gel material. Au and Al were used as electrodes to make Ohmic and Schottky contacts, respectively. The annealing temperature, time and the thickness dependent I-V characteristics were presented in this article.

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High Temperature Superconducting (HTS) Films by EPD Method addition with $BaF_2$ and PEG

  • Soh, Deawha;Korobova, N.;Park, Jung-Cheul;Jeun, Yong-Woo
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 하계학술대회 논문집
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    • pp.250-254
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    • 2000
  • High temperature superconducting films deposited on metal Ag wire were prepared with YBCO powders by electrophoretic deposition method. $I_2$was used as additives for surface charge of YBCO particles. When 2~3 wt.% $BaF_2$ was added in the YBCO suspension, the pores and cracks of film surface were decreased and film density could be increased. In case of YBCO films, the critical current density ($J_{c}$) was calculated at the value of $1458{\;}A/\textrm{cm}^2$ (77K, 0K) by 4 point prove method.

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이소프로판올과 이소부탄을 용매에서의 YBCO 분말 영동전착 (Electrophoretic Deposition of YBCO powder in mixed suspension solution of iso-prophanol and iso-buthanol)

  • 소대화;이영매;박정철
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
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    • pp.288-291
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    • 2001
  • It is very important to select suspension solution for forming electrophoretic deposited YBCO thick film, because it is heavily affected to its superconducting properties. In this paper, high-temperature superconductor films of YBa$_2$Cu$_3$$O_{7-x}$ were fabricated by electrophoretic deposition (EPD) from alcohol-based suspension such as iso-propanol, iso-butanol, and their mixture. For the formation of YBCO dense and adherent coating on a silver wire by EPD, 1% PEG(1000) 2 $m\ell$, as a additive for making their surface crack-free, was used for electrophoresis. As a results, the cracks were considerably decreased and the superconducting critical current density (J$_{c}$) without/with PEG was 1200 A/$\textrm{cm}^2$ and 2020 A/$\textrm{cm}^2$, which films deposited in mix ism-propanol and iso-butanol suspension.ion.

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다결정 3C-SiC/TiW Ohmic Contact에 관한 연구 (Study for ohmic contact of polycrystalline 3C-SiC/TiW)

  • 온창민;정귀상
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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    • pp.1311-1312
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    • 2006
  • This paper describes the ohmic contact formation between a TiW film as a contact material deposied by RF magnetron sputter and polycrystalline 3C-SiC films deposied on thermally grown Si wafers. The specific contact resistance (${\rho}_c$) of the TiW contact was measured by using 4he C-TLM. The contact phase and interfacial reaction between TiW and 3C-SiC at high-temperature were also analyzed by XRD and SEM. All of the samples didn't show cracks of the TiW film and any interfacial reaction after annealing. Especially, when the sample was annealed at $800^{\circ}$ for 30min., the lowest contact resistivity of $2.90{\times}10^{-5}{\Omega}{\cdot}cm^2$ of was obtained due to the improved interfacial adhesion.

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초고온 MEMS용 다결정 3C-SiC의 Ohmic Contact 형성 (Ohmic contact formation of polycrystalline 3C-SiC for high-temperature MEMS applications)

  • 온창민;정귀상
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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    • pp.406-407
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    • 2006
  • This paper describes the ohmic contact formation between a TiW film as a contact material deposied by RF magnetron sputter and polycrystalline 3C-SiC films deposied on thermally grown Si wafers. The specific contact resistance (${\rho}_c$) of the TiW contact was measured by using the C-TLM. The contact phase and interfacial reaction between TiW and 3C-SiC at high-temperature were also analyzed by XRD and SEM. All of the samples didn't show cracks of the TiW film and any interfacial reaction after annealing. Especially, when the sample was annealed at $800^{\circ}$ for 30min., the lowest contact resistivity of $2.90{\times}10^{-5}{\Omega}cm^2$ was obtained due to the improved interfacial adhesion.

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Sol-Gel법을 이용한 알루미나 기판과 동 피복층간의 접착력 특성 (Adhesion characteristics of copper layer fabricated by Sol-Gel process)

  • 김동규;이홍로
    • 한국표면공학회지
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    • 제29권3호
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    • pp.186-194
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    • 1996
  • In this study, ceramic film was coated by a sol-gel process for increasing the adhesion strength between the substrate and copper layer. TEOS and ATSB were used as starting solution of metallic alkoxide. As a result, amorphous-like diffraction pattern after heat treatment at $1200^{\circ}C$ was obtained using X-ray diffractometer. The more contants of $Al_2O_3$ gave rise to the futher advanced cracks. A maximum adhesion strength of 250gf was measured under the condition of 30 Wt.% $Al_2O_3$, which is 5 times greater than that of uncoated one of the ceramic film.

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절삭가공이 알루미늄 경질 아노다이징 피막에 미치는 영향 (Effect of Machining on Hard Anodizing Surface of Aluminum)

  • 김수진;문정일
    • 한국기계가공학회지
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    • 제21권8호
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    • pp.87-92
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    • 2022
  • The Al3003 aluminum plate was cut by grinding, milling, sawing, and shearing, and the hard-anodizing surface of the material was investigated. Large burrs were formed during grinding and milling. The brittle anodized film split and migrated along the deformed aluminum surface. During shearing, the hard-anodized film on the blade entry surface cracks and slides along the deforming aluminum. The cutting heat increased the ductility of the aluminum and further promoted burr formation. The oil-based coolant suppressed burrs and prevented chips from sticking to the endmill. It is better to avoid the high cutting speed and slow material feed rate conditions, which increase the cutting temperature and burr in the band saw.