• 제목/요약/키워드: Codeposition

검색결과 43건 처리시간 0.019초

Co-Si계의 동시증착과 고상반응시 상전이 및 $CoSi_2$ 층의 저온정합성장 (Phase sequence in Codeposition and Solid State Reaction of Co-Si System and Low Temperature Epitaxial Growth of $CoSi_2$ Layer)

  • 박상욱;심재엽;지응준;최정동;곽준섭;백홍구
    • 한국진공학회지
    • /
    • 제2권4호
    • /
    • pp.439-454
    • /
    • 1993
  • The phase sequence of codeposited Co-Si alloy and Co/si multilayer thin film was investigated by differential scanning calormetry(DSC) and X-ray diffraction (XRD) analysis, The phase sequence in codeposition and codeposited amorphous Co-Si alloy thin film were CoSilongrightarrow Co2Si and those in Co/Si multilayer thin film were CoSilongrightarrowCo2Silongrightarrow and CoSilongrightarrowCo2Si longrightarrowCoSilongrightarrowCoSi2 with the atomic concentration ration of Co to Si layer being 2:1 and 1:2 respectively. The observed phase sequence was analyzed by the effectvie heat of formatin . The phase determining factor (PDF) considering structural facotr in addition to the effectvie heat of formation was used to explain the difference in the first crystalline phase between codeposition, codeposited amorphous Co-Si alloy thin film and Co/Si multilayer thin film. The crystallinity of Co-silicide deposited by multitarget bias cosputter deposition (MBCD) wasinvestigated as a funcion of deposition temperature and substrate bias voltage by transmission electron microscopy (TEM) and epitaxial CoSi2 layer was grown at $200^{\circ}C$ . Parameters, Ear, $\alpha$(As), were calculate dto quantitatively explain the low temperature epitaxial grpwth of CoSi2 layer. The phase sequence and crystallinity had a stronger dependence on the substrate bias voltage than on the deposition temperature due to the collisional daxcade mixing, in-situ cleannin g, and increase in the number of nucleation sites by ion bombardment of growing surface.

  • PDF

Lab scale electrochemical codeposition experiments for comparison to computational predictions

  • Lafreniere, Philip;Zhang, Chao;Simpson, Michael;Blandford, Edward D.
    • Nuclear Engineering and Technology
    • /
    • 제52권9호
    • /
    • pp.2025-2033
    • /
    • 2020
  • Signature-based safeguards (SBS) is being developed to assist tradition nuclear material accountancy methods in tracking material in pyroprocessing facilities. SBS involves identifying off-normal scenarios that would result in improper movement of material in a pyroprocessing facilities and determining associated sensor response signatures. SBS investigations are undertaken in the computational space utilizing an electrochemical transport code known as enhanced REFIN with anodic dissolution (ERAD) to calculate the affect of off-normal conditions in the electrorefiner (ER) on material movement. Work is undertaken to experimentally validate the predictions and assumptions made by ERAD for off-normal occurrences. These experiments were undertaken on a benchtop scale and involved operating an electrochemical cell at 10 separate current densities for constant current operations to deposit U and Gd at a W cathode. These experiments were then modeled using ERAD to compare calculated predictions versus analytical experimental results it was found. It was discovered both the experimental and calculated results reflect a trend of increased codeposition of U and Gd with increasing current density. ERAD was thus demonstrated to be useful for predicting trends from anomalous operation but will require further optimization to be utilized as a quantitative design tool.

아연-니켈합금전착층의 조직특성 (Microstructure of Zn-Ni Alloy Electrodeposir)

  • 예길촌;최성렬;신현준;안덕수
    • 한국표면공학회지
    • /
    • 제21권1호
    • /
    • pp.10-18
    • /
    • 1988
  • The variation of Composition and the microstructure of Zn-Ni alloy electrodespposits were investigated to the electrolysis conditions chloride bath. The codeposition mechanism is of the equilibrium type in the electrolysis condition of the high temperature(6$0^{\circ}C$)and high flow rate (1.2-3.0m/sec). The(411, 330) perferred orienation was mainly developed in the Zn-Ni electrodeposir with ${\gamma}$-phase structure, while the(422.600) orientation was closely related to the commposition and the structure of the alloy electrodeposit.

  • PDF

전기도금법을 이용한 퍼멀로이-실리카 복합도금 (Electrodeposition of Permalloy-Silica Composite Coating)

  • 정명원;김종훈;이흥렬;이재호
    • 마이크로전자및패키징학회지
    • /
    • 제17권4호
    • /
    • pp.83-88
    • /
    • 2010
  • 복합전기도금은 도금 중 반응성이 없는 물질을 첨가하여 도금층 내부에 함께 존재하도록 함으로써 이루어진다. 퍼멀로이는 철과 니켈의 합금을 말하는 것으로써 높은 투자율를 나타내기 때문에 산업 여러 분야에 응용된다. 복합도금을 통해 제품의 미세경도를 향상시킬 수 있으며 이는 제품의 수명과 연관된다. 하지만 실리카 나노분말 표면의 수산화기는 표면을 수분에 취약하게 만들고 이는 나노분말의 응집을 발생시켜 균일한 도금층의 형성을 어렵게 하는 요인이 된다. 본 연구에서는 실리카 나노분말의 응집을 줄이기 위하여 첨가제의 변화, 초음파 처리 시간의 변화를 살펴보았다. 초음파 처리시간의 증가시 입자의 분산효과가 좋았고 조성의 변화가 발생하였다. 첨가제에 따라 표면 형상과 공석되는 실리카 나노입자의 함량 차이가 나타났다. 염기성 도금용액에서 sodium lauryl sulfate를 사용하였을 경우 표면이 매끄럽고 공석되는 실리카 나노분말의 양도 높았다.

표면처리와 전극 재료가 철-니켈 합금 도금에 미치는 영향 (Effects of Surface Treatment of Cathode Materials on the Electrodeposition Behavior of Fe-Ni Alloy)

  • 강나영;이재호
    • 마이크로전자및패키징학회지
    • /
    • 제29권4호
    • /
    • pp.71-75
    • /
    • 2022
  • 본 연구에서는 환원전극 기판이 철-니켈 합금 도금에 미치는 영향을 알아보기 위해 경면 스테인리스강(SS304, SS430)과 티타늄 판을 환원전극으로 사용해 도금을 진행했으며, 티타늄의 경우 3M 황산-메탄올 용액에서 전압과 연마시간을 조절하여 찾은 최적의 시편(10 V, 8 분)과 표면 처리하지 않은 시편을 사용하였다. 도금층의 조성을 분석한 결과, 스테인리스강과 티타늄 기판에서 니켈보다 환원 경향성이 낮은 철이 먼저 환원되는 비정상 도금 현상이 관찰되었으나 도금층의 앞면과 뒷면의 조성 불균일이 확인되었다. 도금 중 포텐셜 변화를 관찰한 결과, 스테인리스강보다 티타늄을 사용했을 때 도금 셀에 높은 과전압이 걸렸으며, 이로 인해 철의 핵생성 속도가 증가해 과전압이 가장 높았던 표면처리를 하지 않은 티타늄에서 형성된 도금층 뒷면의 철 함량이 높아진 것으로 보인다. 또한 티타늄을 기판을 표면 처리했을 때 셀에 걸린 과전압이 낮아진 것을 확인할 수 있었다.

메틸클로로실란류의 열분해를 이용한 탄화규소의 화학증착 (Chemical Vapor Deposition of Silicon Carbide by the Pyrolysis of Methylchlorosilanes)

  • 최병진;박동원;조미자;김대룡
    • 한국세라믹학회지
    • /
    • 제32권4호
    • /
    • pp.489-497
    • /
    • 1995
  • The DDS((CH3)2SiCl2)+H2 gas mixture, where C atoms exist in excess in the molecules, was used for chemical vapor deposition of SiC in order to prevent codeposition of free Si in MTS(Ch3SiCl3)+H2 system. The deposition rate was more rapid than MTS, however differ from that of MTS, it decreased after shwoing a maximum at 140$0^{\circ}C$. The stoichiometry was highly improved by using the DDS as a precursor, although there exist a little pyrolytic C at 150$0^{\circ}C$. The preferred orientation was (220) in MTS, however, it changed to (111) in DDS. The microstructure of the layer deposited at lower temperature were dense, however it grew coarse with the increase in the temperature.

  • PDF

HIGH STRENGTH ALUMINIUM ALLOYS PROCESSED BY SPRAY/CODEPOSITION

  • Juarez-Islas, Julio Alberto
    • 한국재료학회:학술대회논문집
    • /
    • 한국재료학회 1992년도 추계학술발표강연 및 논문개요집
    • /
    • pp.14-14
    • /
    • 1992
  • During the past five years a very successful effort has been made to improve existing and develop new aluminium alloys. The progress achieved has been possible because of the development of new production methods, such as powder metallurgy and spray/deposition. These methods make use of rapid solidification process which alloys compositions other than those achieved by conventional ingot metallurgy. The ingot metallurgy of the 2000 and 7000 series used thus far, as well as the age hardening Al-Li alloys, show several disadvantages caused by the production process. Such problems are primarily coarse intermetallic constituent phases, coarse grains and macrosegregation, resulting in low fracture toughness. The present contribution reports results of an experimental investigation performed on a modern high strength spay deposited aluminium alloy of the Al-Zn-Mg-Cu (7075 and the modified 7150X) type. Results are given in terms of its microstructural characterization by using X-ray diffractomertry and transmission electron microscopic. The mechanical propierties of those alloys in the as-extruded and extruded+aged condition were evaluated by using microhardness Vickers, tensile test and fracture toughness measurements.

  • PDF

$HoSi_2$ 소결체의 전기적 특성 연구 (Electrical properties of sintered $HoSi_2$)

  • 이우선;오금곤;김형곤
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2001년도 하계학술대회 논문집 C
    • /
    • pp.1396-1398
    • /
    • 2001
  • The $HoSi_2$ compounds prepared by codeposition of Si and Ho, and $HoSi_2$ by sintering method were investigated electrical and Hall effect. The crystal structure of samples showed a orthorhombic structure, and lattices constant is a=9.8545 $\AA$, b=7.7935 $\AA$, c=7.8071 $\AA$. Hall effect shows a n-type conductivity in the sintered $HoSi_2$. The electrical resistivity values was 1.608${\Omega}cm^{-1}$ and carrier mobility was $6.9{\times}10^1cm^2/V{\cdot}sec$ at low room temperature.

  • PDF