• 제목/요약/키워드: Mo film

검색결과 674건 처리시간 0.037초

Evaluations of Si based ternary anode materials by using RF/DC magnetron sputtering for lithium ion batteries

  • 황창묵;박종완
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2010년도 제39회 하계학술대회 초록집
    • /
    • pp.302-303
    • /
    • 2010
  • Generally, the high energy lithium ion batteries depend intimately on the high capacity of electrode materials. For anode materials, the capacity of commercial graphite is unlike to increase much further due to its lower theoretical capacity of 372 mAhg-1. To improve upon graphite-based negative electrode materials for Li-ion rechargeable batteries, alternative anode materials with higher capacity are needed. Therefore, some metal anodes with high theoretic capacity, such as Si, Sn, Ge, Al, and Sb have been studied extensively. This work focuses on ternary Si-M1-M2 composite system, where M1 is Ge that alloys with Li, which has good cyclability and high specific capacity and M2 is Mo that does not alloy with Li. The Si shows the highest gravimetric capacity (up to 4000mAhg-1 for Li21Si5). Although Si is the most promising of the next generation anodes, it undergoes a large volume change during lithium insertion and extraction. It results in pulverization of the Si and loss of electrical contact between the Si and the current collector during the lithiation and delithiation. Thus, its capacity fades rapidly during cycling. Si thin film is more resistant to fracture than bulk Si because the film is firmly attached to the substrate. Thus, Si film could achieve good cycleability as well as high capacity. To improve the cycle performance of Si, Suzuki et al. prepared two components active (Si)-active(Sn, like Ge) elements film by vacuum deposition, where Sn particles dispersed homogeneously in the Si matrix. This film showed excellent rate capability than pure Si thin film. In this work, second element, Ge shows also high capacity (about 2500mAhg-1 for Li21Ge5) and has good cyclability although it undergoes a large volume change likewise Si. But only Ge does not use the anode due to its costs. Therefore, the electrode should be consisted of moderately Ge contents. Third element, Mo is an element that does not alloys with Li such as Co, Cr, Fe, Mn, Ni, V, Zr. In our previous research work, we have fabricated Si-Mo (active-inactive elements) composite negative electrodes by using RF/DC magnetron sputtering method. The electrodes showed excellent cycle characteristics. The Mo-silicide (inert matrix) dispersed homogeneously in the Si matrix and prevents the active material from aggregating. However, the thicker film than $3\;{\mu}m$ with high Mo contents showed poor cycling performance, which was attributed to the internal stress related to thickness. In order to deal with the large volume expansion of Si anode, great efforts were paid on material design. One of the effective ways is to find suitably three-elements (Si-Ge-Mo) contents. In this study, the Si based composites of 45~65 Si at.% and 23~43 Ge at.%, and 12~32 Mo at.% are evaluated the electrochemical characteristics and cycle performances as an anode. Results from six different compositions of Si-Ge-Mo are presented compared to only the Si and Ge negative electrodes.

  • PDF

마멸 전극 기법과 교류 임피던스법으로 연구한 스테인리스강의 합금원소(Cr, Mo, N)가 재부동태 특성에 미치는 영향 (Effects of Alloying Elements(Cr, Mo, N) on Repassivation Characteristics of Stainless Steels Studied by the Abrading Electrode Technique and A.C Impedance Spectroscopy)

  • 함동호;김석원;이재봉
    • 전기화학회지
    • /
    • 제3권4호
    • /
    • pp.211-218
    • /
    • 2000
  • 마멸전극기법과 교류 임피던스법으로 스테인리스강의 합금원소, Cr, Mo, N가 합금의 재부동태 특성에 미치는 영향을 조사하였다. Fe-Cr, Fe-Cr-Mo, 304, 304LN, 316, 316LN등의 스테인리스강을 시편으로 사용하였으며 각 합금의 부동태 피막의 전기화학적 특성은 in-situ시험 기법인 d.c와 a.c전기화학적 기법을 각각 이용하였다 스테인리스강이 국부부식에 대하여 강한 저항성을 가지려면 부식 환경에서도 치밀한 부동태 피막을 유지해야 하고 피막의 파괴가 발생하더라도 재부동태 속도가 빨라야 하기 때문에 합금원소가 시간에 따른 재부동태 전류밀도와 재부동태 속도에 미치는 영향을 마멸 전극 시험법과 교류 임피던스 시험법으로 알아보았다. 부동태 피막의 안정성, 재부동태 속도 그리고 합금원소 사이의 관계를 규명하기 위하여 실험결과를 분석하였다.

Mo(100) 표면에 $TiO_2$초박막의 성장과 특성 (Growth and Characterization of Ultra-Thin $TiO_2$Film on Mo(100) Surface)

  • 김대영
    • 대한화학회지
    • /
    • 제41권5호
    • /
    • pp.223-233
    • /
    • 1997
  • 초고진공조에서 산소 분압, $1{\times}10^{-6}$ Torr, 하에서 Ti 금속을 Mo(100)에 증발시킴으로써 $TiO_2$ 초박막을 성장시켰다. Ti 금속을 Mo(100) 표면에 증착시킨 시간에 따른 오재(Auger) 봉우리의 크기 변화율을 조사함으로써 Ti 금속의 증발 속도를 알아내고, 그것을 이용하여 $TiO_2$ 박막 성장시 박막의 두께를 조절하였다. 30 ML, 5 ML, 1.6 ML 두께의 $TiO_2$ 박막을 만들어 박막의 성장메카니즘, 박막의 화학적 조성, 박막의 표면 구조를 연구하였다. 박막의 성장 메커니즘은 층별 성장에 가까운 성장 방식인 것으로 설명할 수 있다. 박막의 화학적 조성은 본체 $TiO_2$ 와 동일하였다. 박막의 표면은 (001) 평면이며, 고온 1200 K에서 비가역적으로 부면화(faceging)한다. 박막으로부터 관찰된 저에너지 전자회절 무늬는 $TiO_2$ (001) 표면이 {011} 평면을 가진 부면을 형성하고 각 부면이 다시 $TiO_2$ (001) 평면에 대하여 $(2\sqrt2{\times}\sqrt2)R45^{\circ}$로 재건축한다는 것으로 설명될 수 있다. 박막은 1300 K의 고온에서 얼마간 열적 불안정성을 보인다. $Ar^+$ 이온으로 스퍼터링한 $TiO_2$ 박막에 대하여 XPS를 이용하여 역시 알아보았다.

  • PDF

수직자기기록매체 CoCrMo 박막의 구조와 자기적 성질 (Structural and Magnetic Properties of perpendicular Recording Medium CoCrMo thin Film)

  • 남인탁;홍양기
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 1988년도 추계학술대회 논문집
    • /
    • pp.46-46
    • /
    • 1988
  • Structural and magnetic properties of Co-Cr-Mo films were investigated in connection with sputtering conditions. Films were prepared using a convention RF sputtering system. X-ray diffractometry, scanning electron microscopy and transmission electron microscopy were employed to investigate structure properties. Vibrating sample magnetometry was used for coercivity and saturation magnetization measurements. Co-Cr-Mo films displayed reasonable values of perpendicular coercivity and saturation magnetization for perpendicular recording media and showed good perpendicular orientation of the hcp c-axis to the film surface. Perpendicular coercivity was strongly dependent upon substrate technique showed better c-axis orientation than hose using the stationary substrate. Co-Cr-Mo films of 2.9 at. % Mo content showed maximum perpendicular coercivity and saturation magnetization. The films deposited at lower Ar pressure showed good magnetic properties. There was no explicit relationship between the columnar structure and c-axis orientation. Co-Cr-Mo films was found to have suitable structural and magnetic properties for perpendicular recording media.

  • PDF

항균성물질이 함유된 세라믹 LDPE필름의 항균효과 및 식품의 저장성 (Antimicrobial Activity and Food Storage of LDPE Ceramic Film Containing Antimicrobial Agents)

  • 김현수;성림식;유대식
    • KSBB Journal
    • /
    • 제15권6호
    • /
    • pp.600-604
    • /
    • 2000
  • 다양한 식품의 미생물에의한 변패를 억제하고 저장성을 높 일수 있는 포장필름을 개발하기위하여, 미생물이 생산하는 천연 항균성 물질을 홉착시킨 합성 세라믹올 첨가하여 세라 믹 LDPE 필륨을 제조하였다. 천연 항균제로는 methanol자화 방선균 MO-16 및 MO-17균이 생산한 항세균제와 새로이 분 리한 방선균 No. 31이 생산한 항진균제를 사용하였다. 방선 균 No. 31이 생산한 항진균성 불질은 배양 4일째 항균효과가 우수하였으며, $121^{\circ}C$에서 15분간 열처리시에도 항균력이 유 지되는 내열성이 확인되었다. 제조한 세라믹 LDPE 필름의 미생불 생육 억제효과를 검토한 결과 조분쇄한 돈육의 경우 포장하여 실온 및 $4^{\circ}C$에서 보존시 시판필름에 비해 미생물 생육 억제효과가 우수하였다. 고제배지에 제조필름을 첨가하 여 E. coli에 대한 항균효과를 검토한 결과 첨가량에 따라 항 균효과가 우수한 것이 입증되었다 제조펼름으로 포장한 6종 류의 식품에 대한 저장성을 검토한 결과 시판필름에 비해 저 장성이 우수한 것이 확인되었으며 특히 양송이에 대한 저장 효과가 우수하였다.

  • PDF

Mo/SiO2/Si(100)기판 위에 MOCVD법으로 성장시킨 AIN박막이용 GHz대역의 FBAR제작에 관한 연구 (Fabrication of GHz-Band FBAR with AIN Film on Mo/SiO2/Si(100) Using MOCVD)

  • 양충모;김성권;차재상;박구만
    • 조명전기설비학회논문지
    • /
    • 제20권4호
    • /
    • pp.7-11
    • /
    • 2006
  • 본 논문에서는 $Mo/SiO_2/Si(100)$ 기판 위에 MOCVD(Metal-Organic-Chemical-Vapor Deposition)법을 이용하여 C축 방향으로 성장시킨 AIN(Aluminum Nitride) 박막을 이용하여 GHz대역 무선 통신에서 사용할 수 있는 FBAR(Film-Bulk-Acoustic Resonator)을 제작하였다. 제작된 공진부의 공진주파수와 반공진주파수는 각각 3.189[GHz]와 3.224[GHz]으로 측정되었으며, Q값(Quality Factor)과 유효한 전기기계 결합계수(${k_{eff}}^2$)는 각각 24.7과 2.65[%]로 평가되었다. AIN의 증착(Deposition) 조건은 $950[^{\circ}C]$의 기판표면(Substrate) 온도, 20Torr의 압력, 25000의 N/Al의 V/III비로 증착하였다. $4{\times}10^{-5}[\Omega{cm}]$의 Mo 하부전극 고유저항과 $Mo/SiO_2/Si(100)$ 기판 위에 AIN(0002) FWHM(Full-Width at Half-Maximum) 4를 갖는 C축 방향성의 AIN 박막을 성공적으로 성장시켰다. 따라서 증착된 AIN박막의 FWHM값은 GHz대역 무선 통신용 RF(Radio Frequency) 밴드 패스 필터 설계에 유용하게 사용될 것이다.

Electronic Behaviors of Passive Films Formed on Fe-Cr and Fe-Cr-Mo Ferritic Stainless Steels Studied by Mott-Schottky and Cyclic Voltammetry Techniques

  • Kim, Suk-Won;Yoon, Sang-In;Lee, Jae-Bong
    • Corrosion Science and Technology
    • /
    • 제2권1호
    • /
    • pp.12-17
    • /
    • 2003
  • The effects of Cr content and film formation potential on electronic behaviors of the passive film on Fe-Cr alloys were investigated in borate buffer solution. Influence of pH on passive films of both Fe-Cr and Fe-Cr-Mo alloys was also investigated. Mott-Schottky and cyclic voltammetry techniques were used to elucidate electronic behaviors of passive films and their electrochemical characteristics. AES analysis of passive films was carried out. Results showed that doping density decreased as Cr content and film formation potentials increased. The addition of Mo to Fe-Cr alloy had little influence on donor densities in pH 9.2 solution but some effects on the decrease in donor densities in pH 1.6 acidic solution.

Influence of Deposition Conditions on the Adhesion of Sputter-deposited MoS$_2$-Ti Films

  • Kim, Sun-Kyu;Yongliang Li
    • 한국표면공학회지
    • /
    • 제37권1호
    • /
    • pp.1-4
    • /
    • 2004
  • MoS$_2$-Ti films were deposited on SKD-11 tool steel substrate by a D.C. magnetron sputtering system. The influence of deposition parameters on the adhesion of the films was investigated by the scratch test. Crosssection morphology was evaluated using FE-SEM. The plasma etching played an important role on the adhesion of the films. The appropriate etching conditions roughened the surface, resulting In the improved adhesion of the film. The adhesion of the film increased with the interlayer thickness up to 110 nm and then decreased slightly with further increasing of interlayer thickness. The adhesion was highest at a bias voltage of -50 V. Further increase of the bias voltage decreased the film adhesion.

RF 스퍼터법을 이용한 Sr2FeMoO6 박막 제조 및 전기전도 특성 (Preparation of Sr2FeMoO6 Thin Films by RF Magnetron Sputtering and Their Electrical Conduction Properties)

  • 유희욱;선호정
    • 한국전기전자재료학회논문지
    • /
    • 제23권12호
    • /
    • pp.966-972
    • /
    • 2010
  • Single-phase $Sr_2FeMoO_6$ thin films were produced by RF magnetron sputtering for use as electrodes in integrated sensors and found to be good conductors at room temperature. The films were deposited from a powder-type sputtering target under various conditions, and were crystallized by annealing. Elimination of $O_2$ gas during deposition, by the use of a solely Ar sputtering gas under a working pressure as low as possible, and vacuum annealing were important to promote the $Sr_2FeMoO_6$ phase. However, oxygen exclusion from sputtering and annealing was not enough to yield single-phase $Sr_2FeMoO_6$: hydrogen annealing was also required. Film production was optimized by varying the deposition parameters and hydrogen annealing conditions. The film had good electrical conduction, with a low resistivity of $1.6{\times}10^{-2}\Omega{\cdot}cm$ at room temperature.

Substrate Temperature Effects on DC Sputtered Mo thin film

  • Ahn, Heejin;Lee, Dongchan;Um, Youngho
    • Applied Science and Convergence Technology
    • /
    • 제26권1호
    • /
    • pp.11-15
    • /
    • 2017
  • To improve the adhesion of Mo thin film as a back contact material, a DC magnetron sputtering system was used to deposit in the form of a bi-layer on soda-lime glass. Films with low resistivity and good adhesion were obtained from this deposition, even though the two qualities were found be hard to obtain at the same time. The best Mo bi-layer showed a resistivity of $8.13{\times}10^{-4}{\Omega}{\cdot}cm$ at $500^{\circ}C$ and $3.0{\times}10^{-3}\;Torr$. The XRD measurements showed that the crystallites of the films were mainly oriented in the (110) direction, the FE-SEM images revealed that the resistivity of the Mo films decreased with increasing substrate temperature, which temperature reduction is accompanied by an increase of the grain size. These experimental results were analyzed using the Fuchs-Sondheimer theory. Our Mo bi-layer film with better crystallinity and lower resistivity can be suitably used as a back-contact layer for CIGS solar cells.