• 제목/요약/키워드: Magnetic Annealing

검색결과 483건 처리시간 0.028초

Physical Property Change of the Gapless Semiconductor $PbPdO_2$ Thin Film by Ex-situ Annealing

  • Choo, S.M.;Park, S.M.;Lee, K.J.;Jo, Y.H.;Park, G.S.;Jung, M.H.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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    • pp.371-372
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    • 2012
  • We have studied lead-based gapless semiconductors, $PbPdO_2$, which is very sensitive to external parameters such as temperature, pressure, electric field, etc[1]. We have fabricated pure $PbPdO_2$, Co- and Mn-doped $PbPdO_2$ thin films using the pulsed laser deposition. Because of the volatile element of Pb, it is very difficult to grow the films. Note that in case of $MgB_2$, Mg is also volatile element. So in order to enhance the quality of $MgB_2$, some experiments are carried out in annealing with Mg-rich atmosphere [2]. This annealing process with volatile element plays an important role in making smooth surface. Thus, we applied such process to our studies of $PbPdO_2$ thin films. As a result, we found the optimal condition of ex-situ annealing temperature ${\sim}650^{\circ}C$ and time ~12 hrs. The ex-situ annealing brought the extreme change of surface morphology of thin films. After ex-situ annealing with PbO-rich atmosphere, the grain size of thin film was almost 100 times enlarged for all the thin films and also the PbO impurity phase was smeared out. And from X-ray diffraction measurements, we determined highly crystallized phases after annealing. So, we measured electrical and magnetic properties. Because of reduced grain boundary, the resistivity of ex-situ annealed samples changed smaller than no ex-situ sample. And the carrier densities of thin films were decreased with ex-situ annealing time. In this case, oxygen vacancies were removed by ex-situ annealing. Furthermore, we will discuss the transport and magnetic properties in pure $PbPdO_2$, Co- and Mn-doped $PbPdO_2$ thin films in detail.

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NiCr 박막 저항계의 열적 안정성에 관한 연구 (The Study on Thermal Stability of NiCr Thin-films Resistor)

  • 김인성;정순종;김도한;송재성
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.168-170
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    • 2001
  • The NiCr is an important material for present thin-film resistor application owing to its low TCR and thermal stability. In this work, the NiCr thin films were deposited on corning glass substrate by reactive magnetron sputtering and the annealing at temperatures range from 300 to $500^{\circ}C$ for 20 min in vacuum. X-ray, AFM, $R_s$(surface leakage current) have been used to study the structural and electrical properties of the NiCr thin films. The high precision NiCr thin films resistor with TCR(temperature coefficient of resistance) of less then 10 ppm/$^{\circ}C$ was obtained under in in-situ annealing at $300^{\circ}C$ on Cr buffer layer substrate. It is clear that the NiCr thin-films resistor electrical properties are low TCR related with it's annealing and buffer layer condition. NiCr thin film resistor having a good thermal stability and low TCR properties are expected for the application to the dielectric material of passive component.

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변압기 철심용 Fe-B-Si비정질 합금의 철손 특성 (Core Losses of Amorphous Fe-B-Si Alloy for Transformer Core)

  • 김기욱;송재성;홍진완;강원구
    • 대한전기학회논문지
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    • 제40권1호
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    • pp.67-72
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    • 1991
  • For improving the magnetic properties of the amorphous Fe-B-Si alloy, we annealed the sample in a magnetic field oriented in the plane of the ribbon longitudinal to its long axis. By field annealing, coercive force and total core loss are reduced from 0.04 Oe to 0.02 Oe, and from 0.25 watt/kg to 0.15 watt/kg respectively in comparsion with non-field annealed specimen. These reductions were caused by the formation of 180 dcmain wall parallel to the annealing field due to the induced anisotropy.

Magnetic Properties of Al-Co-N Thin Films Dispersed with Co Particles

  • Han, Chang-Suk
    • 열처리공학회지
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    • 제21권1호
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    • pp.3-9
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    • 2008
  • Al-Co-N thin films, Al-Co-N/Al-N and Al-Co-N/Al-Co multilayers containing various amounts of Co content were deposited by using a two-facing targets type dc sputtering (TFTS) system. The films were also annealed successively and isothermally at different annealing temperatures. Irrespective of Co content and preparation methods, all the as-deposited films were observed non-magnetized. It was found that annealing conditions can control the magnetic and electrical properties as well as the microstructure of the films.

박막 두께 및 열처리가 수직자기이방성을 갖는 CoSiB/Pd 다층박막의 자기적 특성에 미치는 영향 (Influence of Layer-thickness and Annealing on Magnetic Properties of CoSiB/Pd Multilayer with Perpendicular Magnetic Anisotropy)

  • 정솔;임혜인
    • 한국자기학회지
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    • 제26권3호
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    • pp.76-80
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    • 2016
  • CoSiB은 비정질 구조를 갖는 강자성체 물질이며, CoSiB과 Pd을 포함한 다층박막은 수직자기이방성을 갖는다. 수직자기이방성은 수평자기이방성에 비해 STT-MRAM에 적용되기에 좋은 이점이 있으며, 특히 비정질 강자성체를 포함한 다층박막은 결정질강자성체를 포함한 다층박막과 비교하여 몇 가지 이점을 지니는데, 첫째는 grain boundary가 없다는 것이며 둘째는 결정질 재료에 비교하여 열적안정성이 보다 좋다는 것이다. 이러한 이유에 따라 우리는 비정질 강자성체 $Co_{75}Si_{15}B_{10}$을 포함하는 다층박막을 제작하여 그 자기적 특성을 연구하였다. 본 연구는 [CoSiB(3, 4, 5, 6) ${\AA}$/Pd(11, 13, 15, 17, 19, 24${\AA})]_5$ 다층박막을 제작하여 VSM 측정을 통해 두께에 따른 그 자기적 특성의 변화를 살펴보았으며, 이후 일부 다층박막의 열처리를 통해 온도에 따른 자기적 특성의 변화추이를 조사하였다. 포화자화값과 보자력은 CoSiB과 Pd 각 층의 두께 변화에 따라 증가와 감소를 반복하였으며, 열처리 온도의 범위는 상온에서 $500^{\circ}C$까지로 특정 온도에서 보자력의 증대를 보였다.

Microstructure and Magnetic Properties of $Nd_2Fe_{14}B/{\alpha}-Fe$ Nanocomposite Prepared by HDDR Combined with Mechanical Milling

  • Hu, Lianxi;Wang, Erde;Guo, Bin;Shi, Gang
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.1286-1287
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    • 2006
  • [ $Nd_2Fe_{14}B/{\alpha}-Fe$ ] nanocomposite powders with a nominal composition of $Nd_{12}Fe_{82}B_6$ were prepared by HDDR combined with mechanical milling. The microstructure was studied by Mossbauer spectrometry and TEM. The magnetic properties were investigated by VSM using bonded magnet samples. The results showed that the annealing temperature had significant influence on both the recombination kinetics and the grain size of the $Nd_2Fe_{14}B$ and ${\alpha}-Fe$ phases, and the bonded magnets presented the best magnetic properties when the nanocomposite powders were prepared by annealing at $760^{\circ}C$ for 30 min.

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${Li_2}{CO_3}$첨가에 의한 $BaSr(TiO_3)$의 저온 소결과 가변유전 특성 (Tunable properties and low temperature sintering of BST thick films added ${Li_2}{CO_3}$)

  • 김인성;민복기;정순종;송재성;전소현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.7-9
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    • 2006
  • $(BaSr)TiO_3$ thick films were prepared by tape casting method using $BaTiO_3$ and $SrTiO_3$ powder slurry in order to investigate dielectric properties and low temperature sintering. Sintering density was $5.7\;g/cm^3$ and the BST sample exhibited the maximum dielectric constant, tunability at temperatures near phase transition point. The dielectric constant was increased and curie temperature was shifted to higher temperature with increasing of annealing temperature.

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자화된 SrO 6$Fe_{2}O_{3}$ 세라믹스와 전해질 계면의 전기물리적 현상에 미치는 Curie점 열처리 효과 (The Effect of Curie Point Annealing on Electrophysical Phenomena at the Magnetized SrO 6$Fe_{2}O_{3}$ Ceramics/Electrolyte Interface)

  • 천장호;손광철;라극환
    • 전자공학회논문지A
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    • 제31A권7호
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    • pp.63-68
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    • 1994
  • The Curie point annealing effects on electrophysical phenomena at the magnetized strontium ferrite(SrO$\cdot$ 6$Fe_{2}O_{3}$) ceramics electrode/10$^{-3}$M KC1 aqueous electrolyte interfaces have been studied using cyclic voltammetric, normal pulse voltammetric, chronocoulometric, and electrochemical impedance techiques. After the Curie point annealing the magnetic flux densities of the speciment was decreased from 900-1100 gauss to 1-2 gauss, i.e. demagnetized. The real component of interfacial impedance was decreased from 7280-7320 ohm to 790-830 ohm. The adsorption and the charge on the electrical double layer was increased from 0 $\mu$C to -58 $\mu$C. The Curie point annealing and the related electrical double layer effect can influence not only the electrophysical properties of the strontium ferrite ceramics electrode itself but also the electrochemical phenomena at the electrode interface. This experimental results suggest that the Curie point annealing and the related electrical double layer effect can be applied to electrochemical magnetic sensors.

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