• 제목/요약/키워드: Compound layer

검색결과 686건 처리시간 0.023초

BCl$_3$/SF6 gas chemistries에 의한 TiW막의 식각특성 연구 (A Study on the Etching Characateristics of TiW Films using BCl$_3$/SF6/ gas chemistries)

  • 권광호;김창일;윤선진;김상기;백규하;남기수
    • 전자공학회논문지D
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    • 제34D권3호
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    • pp.1-8
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    • 1997
  • The surface properties after plasma etching of TiW alloy using the chemistries of BCl$_{3}$ and SF$_{6}$ gases with varying mixing ratio have been investigated using XPS(X-ray photoelectron spectrocopy). The elements existed on the etched sampled have been extracted with BCL$_{3}$/SF$_{6}$ ratio and their chemical binding states have also been analysed. It was confirmed that the thickness of native oxide formed on the TiW films is thinner than 10nm by using Ar sputtering. At the same time, the roughness of etched surface has been esamnied using AFM (atomic force microscopy). on the basis of the basis of this results, the relations between the caanges of oxygen contents detected by XPS and the rouhness of etched surface have been discussed. And the etch rate and etched profile of Tiw films have been examined and the changes of the etch rate and etched prfile have been discussed with XPS results. From XPS results, the role of passivation layer consisted of Ti-S compound with XPS results. From XPS results, the role of passivation layer consisted of Ti-S compound has been proposed. Ti-S compound seems to make a role of passivation layer that surpresses Ti-O formation.ion.

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BNi-2계 삽입금속에 의한 SUS304 스테인리스강 접합체의 강도와 조직에 미치는 브레이징 온도의 영향 : Ni기 삽입금속에 의한 브레이징 접합성의 기초적 검토(II) (Influence of Brazing Temperature on Strength and Structure of SUS304 Stainless Steel Brazed System with BNi-2 Filler Metal : Fundamental Study on Brazeability with Ni-Based Filler Metal(II))

  • 이용원;김종훈
    • 한국재료학회지
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    • 제17권3호
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    • pp.179-183
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    • 2007
  • A plate heat exchanger (PHE) normally uses vacuum brazing technology for connecting plates and fins. However, the reliability of high temperature brazing, especially with nickel-based filler metals containing boron the formation of brittle intermetallic compounds (IMCs) in brazed joints is of major concern. since they considerably degrade the mechanical properties. This research was examined the vacuum brazing of commercially SUS304 stainless steel with BNi-2 (Ni-Cr-B-Si) filler metal, and discussed to determine the influence of brazing temperatures on the microstructure and mechanical strength of brazed joints. In the metallographic analysis it is observed that considerable large area of Cr-B intermetallic compound phases at the brazing layer and the brazing tensile strength is related to removal of this brittle phase greatly. The mechanical properties of brazing layer could be stabilized through increasing the brazing temperature over $100^{\circ}C$ more than melting temperature of filler metals, and diffusing enough the brittle intermetallic compound formed in the brazing layer to the base metal.

수화된 코발트에 도데칸술폰이 층상 삽입된 화합물의 가변 층 거리에 대한 연구 (Variable Layer Distance of Intercalates of Dodecanesulfonate in Hydrated Cobalt Compound)

  • 허영덕;전태현;박용준
    • 분석과학
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    • 제13권1호
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    • pp.66-71
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    • 2000
  • 수화된 코발트에 도데칸술폰이 층간 삽입된 화합물을 합성하였다. 고온 X-선 회절 데이터를 분석한 결과 화합물은 층상구조를 가짐을 확인하였다. 층 거리는 $30^{\circ}C$에서 $200^{\circ}C$로 증가함에 따라서 $19.1{\AA}$에서 $34.7{\AA}$까지 변하는 것을 확인하였다. 화합물의 온도를 증가시키면 층간 삽입된 도데칸술폰이 단일 층에서 이중 층구조로 변화가 생긴다. 따라서 온도를 변화시키면서 층상화합물의 층 거리를 조절할 수 있게 됨을 확인하였다.

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Pancreatic lipase Inhibitory Compound from Apis mellifera venome

  • Kim, Jun-Ran;Kim, Shin-Duk
    • International Journal of Industrial Entomology and Biomaterials
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    • 제16권2호
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    • pp.57-59
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    • 2008
  • While searching for pancreatic lipase inhibitors, the active compound was found in a methanol extract of Apis mellifera venome. The active compound was isolated by Diaion HP-20 column chromatography, thin layer chromatography and HPLC. The active compound is stable to the extreme pH and heat. There is no loss of activity both in acidic and alkaline solution in the pH range of 2 to 11 by heating for 15 minutes at $90^{\circ}C$. The rf value of the compound was 0.51 at TLC with butanol : methanol: water (4:1:2) solvent system. The molecular weight of the compound was determined to be 293 by EI-MS.

이온 실화처리한 Ni-Cr-Mo강의 저온파괴인성에 관한 연구 (A Study on the Low Temperature Fracture Toughness of Ion-nitrided Ni-Cr-Mo Steel)

  • 오세욱;윤한기;문인철
    • 한국해양공학회지
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    • 제1권2호
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    • pp.101-112
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    • 1987
  • Fracture toughness characterization in the transition region is examined for heat-treated and ionnitrided Ni-Cr-Mo steel. After heat treatment for the specimens of Ni-Cr-Mo steel, organizations of specimens-specimens which are heat-treated and ion-nitrided for 4 hours at 500 .deg. C and 5 torr in 25%N/dub 2/-75%H/sub 2/mixed gas-, hardness variety, and X-ray diffraction pattern of the ion-nitriding compound layer are observed. Fracture toughenss test of unloading compliance method were conducted over the regions from room trmperature to -70.deg. C. The compound layer was consisted of r'=Fe/sub 4/N phase and ion-nitrided layer's depth was 200mm from surface. The transition regions of heat-treated and ion-nitrided specimens were about -30.deg. C and -50.deg. C, respectively. The transition region of ion-nitrided specimens is estimated less than that of heat-treated one, and this is the effect of ion-nitriding.

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자동차 엔진부품용 Shaft에 플라즈마 산질화기술 적용 (The Application of Plasma Nitrocarburizing and Plasma Post Oxidation Technology to the Automobile Engine Parts Shafts)

  • 전은갑;박익민;이인섭
    • 한국재료학회지
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    • 제16권11호
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    • pp.681-686
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    • 2006
  • Plasma nitrocarburising and plasma post oxidation were performed to improve the wear and corrosion resistance of S45C and SCM440 steel by a plasma ion nitriding system. Plasma nitrocarburizing was conducted for 3h at $570^{\circ}C$ in the nitrogen, hydrogen and methane atmosphere to produce the ${\varepsilon}-Fe_{2-3}$(N, C) phase. Plasma post oxidation was performed on the nitrocarburized samples with various oxygen/hydrogen ratio at constant temperature of $500^{\circ}C$ for 1 hour. The very thin magnetite ($Fe_3O_4$) layer $1-2{\mu}m$ in thickness on top of the $15{\sim}25{\mu}m$ ${\varepsilon}-Fe_{2-3}$(N, C) compound layer was obtained by plasma post oxidation. A salt spray test and electrochemical testing revealed that in the tested 5% NaCl solution, the corrosion characteristics of the nitrocarburized compound layer could be further improved by the application of the superficial magnetite layer. Throttle valve shafts were treated under optimum plasma processing conditions. Accelerated life time test results, using throttle body assembled with shaft treated by plasma nitrocarburising and post oxidation, showed that plasma nitrocarburizing and plasma post oxidation processes could be a viable technology in the very near future which can replace $Cr^{6+}$ plating.

Superconductivity of infinite layer cuprate

  • Lee, Sung-Ik;Jung, Chang-Wook;Kim, Ji-Yeon;Kim, Heon-Jung;Park, Min-Seok
    • 한국초전도학회:학술대회논문집
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    • 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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    • pp.1-1
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    • 2000
  • The infinite layer compound $ACuO_2$, (A-Alkaline earth) consists of infinite stacking of $CuO_2$ planes separated only by alkaline earth ions. This compound attracted much attention because it contains only key ingredient of all cuprate high temperature superconductor; $CuO_2$ plane with controllable carrier concentration without charge reservoir block. High pressure synthesis method has been found to be preferable for this system due to its ability of doping various lanthanide ion into A site with larger superconducting volume fraction. But rigorous study on this rudimentary compound has been hindered by insufficient quality of sample. Especially superconductlng volume fraction was often too small to identify its origin. In this presentation, we report high pressure synthesis of $Sr_{0.9}Ln_{0.1}CuO_2$ (Ln=La, Sm). By controlling the heating temperature precisely during high pressure synthesis we could have superconductors with quite high superconducting volume fraction for this compound. The magnetic properties of the graln aligned samples show very different behavior compared to the cuprate high temperature superconductors. Details will be discussed.

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다층 리지스트 및 화합물 반도체 기판 구조에서의 전자 빔 리소그래피 공정을 위한 몬테 카를로 시뮬레이션 모델 개발 (A Monte Carlo Simulation Model Development for Electron Beam Lithography Process in the Multi-Layer Resists and Compound Semiconductor Substrates)

  • 손명식
    • 한국진공학회지
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    • 제12권3호
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    • pp.182-192
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    • 2003
  • 밀리미터파 대역용 고속 PHEMT 소자 제작 및 개발을 위하여 다층 리지스트 및 다원자 기판 구조에서 전자빔 리소그래피 공정을 분석할 수 있는 새로운 몬테 카를로 시뮬레이션 모델을 개발하였다. 전자빔에 의해 다층 다원자 타겟 기판 구조에 전이되는 에너지를 정확하고 효율적으로 계산하기 위하여 다층 리지스트 및 다층 다원자 기판 구조에서 시뮬레이션 가능하도록 새로이 모델링하였다. 본 논문에서 제안 개발된 모델을 사용하여 PHEMT 소자의 전자빔 리소그래피에 의한 T-게이트 형성 공정을 시뮬레이션하고 SEM측정 결과와 비교 분석하여 타당성을 검증하였다.

3%Cr-Mo-V강의 2단 가스질화처리를 통한 표면경화 및 내마모성 연구 (A Study on Wear Resistance and Surface Hardening of 3%Cr-Mo-V Steel by Two-step Gas Nitriding)

  • 정길봉
    • 열처리공학회지
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    • 제22권6호
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    • pp.361-367
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    • 2009
  • The two-step gas nitriding was adopted to increase the depth of surface hardening in 3%Cr-Mo-V steel. The two-step gas nitriding consisted of Step I; $520^{\circ}C{\times}20\;hrs$ and Step II; $550^{\circ}{\times}70\;hrs$. The layer of two-step gas nitriding showed better uniformity and deeper nitriding layer than one-step gas-nitriding layer. The maximum surface hardness showed the value of 850 Hv. The maximum depth of nitrogen permeation showed $750\;{\mu}m$ (350 Hv). X-ray diffraction analysis showed that compound layer was mainly consisted of CrN and $\varepsilon-Fe_3N$ phases. These phases were presumed contributing to surface hardening and wear resistance. However, the corrosion resistance of gas-nitrided Cr-Mo-V steel were not improved in the solution of 1 N HCl and NaOH. Therefore, it is necessary that the continuous study for improvement of corrosion resistance hereafter.

플라즈마분체 오버레이법에 의한 알루미늄합금 표면의 경화특성에 관한 연구(I) -후막 표면 합금화층의 형성조건과 그 조직- (Hardening Characteristics of Aluminum Alloy Surface by PTA Overlaying with Metal Powders (I))

  • 이규천;;강원석;이영호
    • Journal of Welding and Joining
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    • 제12권4호
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    • pp.85-101
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    • 1994
  • Effect of Cr, Cu and Ni metal powders addition on the alloyed layer of aluminum alloy (AC2B) has been investigated with the plasma transferred arc (PTA) overlaying process. The overlaying conditions were 125-200A in plasma arc current, 150mm/min in process speed and 5-20g/min in powder feeding rate. Main results obtained are summarized as follows: 1) It was made clear that formation of thick surface alloyed layer on aluminum alloy is possible by PTA overlaying process. 2) The range of optimum alloying conditions were much wider in case of Cu and Ni powder additions than the case of Cr powder addition judging from the surface appearance and the bead macrostructure. 3) Alloyed layer with Cu showed almost the homogeneous microstructure through the whole layer by eutectic reaction. alloyed layers with Cr and Ni showed needle-like and agglomerated microstructures, the structure of which has compound layer in upper zone of bead by peritectic and eutectic-peritectic reactions, respectively. 4) Microconstituents of the alloyed layer were analyzed as A1+CrA $l_{7}$ eutectics, C $r_{2}$al sub 11/, CrA $l_{4}$, C $r_{4}$A $l_{9}$ and C $r_{5}$A $l_{*}$ 8/ for Cr addition, Al+CuA $l_{2}$(.theta.) eutectics and .theta. for Cu addition, and Al+NiA $l_{3}$ eutectics. NiA $l_{3}$, N $i_{2}$A $l_{3}$ and NiAl for Ni addition. 5) Concerning defect of the alloyed layer, many blow holes were seen in Cr and Ni additions although there was lesser in Cu addition. Residual gas contents in blow hole for Cu and Ni alloyed layer were confirmed as mainly $H_{2}$ and a littie of $N_{2}$ Cracking was observed in compound zone of the alloyed layer in case of Cr and Ni addition but not in Cu alloyed layer.r.r.

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