• 제목/요약/키워드: Insulating layer

검색결과 356건 처리시간 0.028초

표면 양생시트 조합에 의한 서중콘크리트 표면온도 이력 비교 (Comparison of Temperature History of Concrete with the Combination of the Various Surface Curing Sheets at Hot Weather Condition)

  • 이주석;김종백;김종;한민철;한천구
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2006년도 추계 학술논문 발표대회 논문집
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    • pp.87-90
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    • 2006
  • This study investigates the temperature history of slab mock-up specimens for hot weather concreting applying various surface insulating methods, in order to improve concrete quality at hot weather condition. Test showed that the use of insulating blanket or a bubble sheet on upper section of slab prevented from abrupt increase of temperature and vaporization of moisture during early curing at hot weather circumstance. In addition, it secured higher strength at early age. Therefore it is concluded that concrete construction insulating with the bubble sheet will reduce the plastic and drying shrinkage as well as improve strength at early age, thus securing concrete duality.

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ICP 스퍼터를 이용한 TMR 소자 제작에서 절연막의 플라즈마 산화시간에 따른 미세구조 및 자기적 특성 변화 (Effect of plasma oxidation time on TMR devices prepared by a ICP sputter)

  • 이영민;송오성
    • 한국재료학회지
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    • 제11권10호
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    • pp.900-906
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    • 2001
  • We prepared tunnel magnetoresistance(TMR) devices of Ta($50\AA$)/NiFe($50\AA$)/IrMn(150$\AA$)/CoFe($50\AA$)/Al ($13\AA$)-O/CoFe($40\AA$)/NiFe($400\AA$)/Ta(50$\AA$) structure which has 100$\times$100 $\mu\textrm{m}^2$ junction area on $2.5\Times2.5 cm^{2}$ $Si/SiO_2$ ($1000\AA$) substrates by a inductively coupled plasma(ICP) magnetron sputter. We fabricated the insulating layer using a ICP plasma oxidation method by varying oxidation time from 80 sec to 360 sec, and measured resistances and magnetoresistance(MR) ratios of TMR devices. We used a high resolution transmission electron microscope(HRTEM) to investigate microstructural evolution of insulating layer. The average resistance of devices increased from 16.38 $\Omega$ to 1018 $\Omega$ while MR ratio decreased from 30.31 %(25.18 %) to 15.01 %(14.97 %) as oxidation time increased from 80 sec to 360 sec. The values in brackets are calculated values considering geometry effect. By comparing cross-sectional TEM images of 220 sec and 360 sec-oxidation time, we found that insulating layer of 360 sec-oxidized was 30 % and 40% greater than that of 150 sec-oxidized in thickness and thickness variation, respectively. Therefore, we assumed that increase of thickness variation with oxidation time is major reason of MR decrease. The resistance of 80 sec-oxidized specimen was 160 k$\Omega$$\mu\textrm{m}^2$ which is appropriate for industrial needs of magnetic random access memory(MRAM) application.

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Fabrication of interface-controlled Josephson junctions using Sr$_2$AlTaO$_6$ insulating layers

  • Kim, Jun-Ho;Choi, Chi-Hong;Sung, Gun-Yong
    • 한국초전도학회:학술대회논문집
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    • 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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    • pp.165-168
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    • 2000
  • We fabricated ramp-edge Josephson junctions with barriers formed by interface treatments instead of epitaxially grown barrier layers. A low-dielectric Sr$_2$AlTaO$_6$(SAT) layer was used as an ion-milling mask as well as an insulating layer for the ramp-edge junctions. An ion-milled YBa$_2$Cu$_3$O$_{7-x}$ (YBCO)-edge surface was not exposed to solvent through all fabrication procedures. The barriers were produced by structural modification at the edge of the YBCO base electrode using high energy ion-beam treatment prior to deposition of the YBCO counter electrode. We investigated the effects of high energy ion-beam treatment, annealing, and counter electrode deposition temperature on the characteristics of the interface-controlled Josephson junctions. The junction parameters such as T$_c$, I$_c$c, R$_n$ were measured and discussed in relation to the barrier layer depending on the process parameters.

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$(Sr{\cdot}Ca)TiO_{3}$ 세라믹스의 용량-전압 특성 (Capacitive-Voltage properties of$(Sr{\cdot}Ca)TiO_{3}$ Ceramics)

  • 강재훈;최운식;김충혁;김진사;박용필;송민종
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.34-37
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    • 2001
  • In this study, the capacitance-voltage properties of $(Sr_{1-x}\cdot Ca_x)TiO_3(0.05{\leq}x{\leq}0.20)$-based grain boundary layer ceramics were investigated. The ceramics were fabricated by the conventional mixed oxide method. The sintering temperature and time were $1480\sim1500^{\circ}C$ and 4 hours. respectively. The 2nd phase formed by the thermal diffusion of CuO from the surface leads to very excellent dielectric properties, that is, ${\varepsilon}_r$ >50000, tan$\delta$ <0.05, ${\Delta}C$ < ${\pm}10%.$ The capacitance is almost unchanged below about 20[V] but it decreases slowly about 20[V]. The results of the capacitance-voltage properties indicated that the grain boundary was composed of the continuous insulating layers.

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실리콘 고무의 플라즈마 표면처리된 반도전-절연계면 처리에 따른 접착특성과 절연성능 (Adhesion and Electrical Performance by Plasma Treatment on Semiconductive-Insulation Interface Layer of Silicone Rubber)

  • 황선묵;이기택;홍주일;허창수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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    • pp.11-14
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    • 2004
  • In this paper, the effect of adhesion properties of semiconductive-insulating interface layer of silicone rubber on electrical properties was investigated. The modifications produced on the silicone surface by oxygen plasma were accessed using ATR-FTIR, contact angle and AFM. Adhesion was obtained from T-peel tests of semiconductive layer having different treatment durations. In addition, ac breakdown test was carried out for elucidating the change of electrical property with duration of plasma treatment. From the results, the treatment in the oxygen plasma produced a noticeable increase in surface energy, which can be mainly ascribed to the the creation of O-H and C=O. It is observed that adhesion performance was determined by not surface energy but roughness level of silicone surface. It is found that ac dielectric strength was increased with improving the adhesion between the semiconductive and insulating interface.

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산화 그래핀을 절연층으로 사용한 유연한 ReRAM과 다층 절연층 ReRAM의 제작 방법 및 결과 비교 (A Review: Comparison of Fabrication and Characteristics of Flexible ReRAM and Multi-Insulating Graphene Oxide Layer ReRAM)

  • 김동균;김태헌;윤태환;박정호
    • 전기학회논문지
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    • 제65권8호
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    • pp.1369-1375
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    • 2016
  • A rapid progress of the next-generation non-volatile memory device has been made in recent years. Metal/insulator/Metal multi-layer structure resistive RAM(ReRAM) has attracted a great deal of attention because it has advantages of simple fabrication, low cost, low power consumption, and low operating voltage. This paper describes the working principle of the ReRAM device, a review of fabrication techniques, and characteristics of flexible ReRAM devices using graphene oxide as an insulating layer and ReRAM devices using multi-layered insulator. The switching characteristics of the above ReRAM devices have been compared. The oxidized graphene could be employed as an insulator of next generation ReRAM devices.

터널링 박막 두께 변화에 따른 부동 게이트 유기 메모리 소자 (Floating Gate Organic Memory Device with Tunneling Layer's Thickness)

  • 김희성;이붕주;신백균
    • 한국진공학회지
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    • 제21권6호
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    • pp.354-361
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    • 2012
  • 유기 메모리 절연막 제작을 위해 일반적으로 사용되어지는 습식법이 아닌 건식법 중 플라즈마 중합법을 이용하였다. 유기 절연 박막으로 사용된 단량체는 Styrene과 MMA을 사용하고, 터널링 박막은 MMA를 사용하며, 메모리 박막은 열기상증착법을 이용한 Au 박막을 사용하였다. 최적화된 소자의 구조는 Au의 메모리층의 두께를 7 nm, Styrene 게이트 절연막의 두께를 400 nm, MMA 터널링 박막의 두께를 30 nm로 증착하여 제작된 부동 게이트형 유기 메모리 소자는 40/-40 V의 double sweep시 27 V의 히스테리시스 전압을 얻을 수 있었다. 이 특성을 기준하여 유기 메모리의 전하 포집 특성을 얻을 수 있었다. 유기 재료 중 MMA 대비 Styrene의 전하 포집 특성이 좋은 것으로 보아 향후 부동 게이트인 Au 박막을 유기 재료인 Styrene으로 대체하여 플렉시블 소자의 가능성을 기대한다.

2층 고온초전도 전력케이블 코어의 전자장 해석 (Electro-magnetic Field Analysis of 2-Layer HTS Power Transmission Cable Core)

  • 조전욱;주진홍;김석환;배준한;김해종;김해준;성기철;홍정표
    • 한국초전도저온공학회:학술대회논문집
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    • 한국초전도저온공학회 2003년도 학술대회 논문집
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    • pp.269-271
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    • 2003
  • A typical HTS power transmission cable has multi-layer conductor structure to increase the current capacity. The tapes of the innermost layer are wound on a round former, and adjacent tapes of another layer are separated by a thin insulating film. In steady state, the total current flows in the conductor layer, and consequently there is magnetic field between the inner and outer layer. This paper describes a magnetic field amplitude around the conductor layer and the HTS tape by a transport current. Also, this paper will help for future cable conductor prototypes.

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다층구조를 적용한 백색 전계발광소자의 발광효율 향상 (Enhancement of Emission Efficiency of Multilayer White Light Organic Electroluminescent Device)

  • 김주승;구할본
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 춘계학술대회 논문집 센서 박막재료
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    • pp.27-31
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    • 2001
  • We fabricated organic electroluminescent(EL) devices with mixed emitting layer of poly(N-vinylcarbazole)(PVK), 2,5-bis(5'-tert-butyl-2-benzoxazoly)thiophene(BBOT), N,N'-diphenyl-N,N'-(3-methyphenyl)-1,1'-biphenyl-4, 4'-diarnine(TPD) and poly(3-hexylthiophene)(P3HT). To improve the external quantum efficiency of EL devices, we added the functional layer to the devices such as LiF insulating layer, carrier confinement layer(BBOT) and hole injection layer(CuPc). In the ITO/emitting layer/Al device, the maximum quantum efficiency at 15V was $1.88{\times}10^{-5}%$. And then, it is increased by a factor of 27 to $5.2{\times}10^{-3}%$ in ITO/CuPc/emitting layer/BBOT/LiF/Al device at 15V.

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