• 제목/요약/키워드: Hysterisis

검색결과 83건 처리시간 0.032초

ZnO 나노선 - Au 나노입자 하이브리드 메모리 소자 (A ZnO nanowire - Au nanoparticle hybrid memory device)

  • 김상식;염동혁;강정민;윤창준;박병준;김기현;정동영;김미현;고의관
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
    • /
    • pp.20-20
    • /
    • 2007
  • Nanowire-based field-effect transistors (FETs) decorated with nanoparticles have been greatly paid attention as nonvolatile memory devices of next generation due to their excellent transportation ability of charge carriers in the channel and outstanding capability of charge trapping in the floating gate. In this work, top-gate single ZnO nanowire-based FETs with and without Au nanoparticles were fabricated and their memory effects were characterized. Using thermal evaporation and rapid thermal annealing processes, Au nanoparticles were formed on an $Al_2O_3$ layer which was semi cylindrically coated on a single ZnO nanowire. The family of $I_{DS}-V_{GS}$ curves for the double sweep of the gate voltage at $V_{DS}$ = 1 V was obtained. The device decorated with nanoparticles shows giant hysterisis loops with ${\Delta}V_{th}$ = 2 V, indicating a significant charge storage effect. Note that the hysterisis loops are clockwise which result from the tunneling of the charge carriers from the nanowire into the nanoparticles. On the other hand, the device without nanoparticles shows a negligible countclockwise hysterisis loop which reveals that the influence of oxide trap charges or mobile ions is negligible. Therefore, the charge storage effect mainly comes from the nanoparticles decorated on the nanowire, which obviously demonstrates that the top-gate single ZnO nanowire-based FETs decorated with Au nanoparticles are the good candidate for the application in the nonvolatile memory devices of next generation.

  • PDF

Laser CVD에 의한 SiON막의 형성과 그 특성 (The Formation and Characteristics of Laser CVD SiON Films)

  • 권봉재;박종욱;천영일;이철진;박지순;성영권
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1991년도 추계학술대회 논문집 학회본부
    • /
    • pp.241-244
    • /
    • 1991
  • In this paper, we introduced Silicon Oxynitride films deposited by Laser CVD, and evaluated the electrical breakdown of these films by TZDB(Time Zero Dielectric Breakdown) and TDDB(Time Dependent Dielectric Breakdown) test. In addition, high frequency C-V test was done in order to calculate hysterisis and flatband voltage(before and after electric field stress). Failure times against eletric field are examined and electric field accelation factor $\beta$ are obtained, and long term reliability was also described by extrapolating into life time in the operating voltage(5V). In this experiments, the deposited films with increased temperature represented small flatband voltage, hysterisis and favorable breakdown characteristics, this is why the hydrogen in the film was decreased and the film was densified, long term reliability was good in the laser CVD SiON films.

  • PDF

수술용 강선에 대한 인장력 측정센서의 설계 및 특성평가 (Design and Evaluation of the Tension Sensor for Surgical Steel Wires)

  • 주진원;이봉식
    • 대한기계학회논문집A
    • /
    • 제21권2호
    • /
    • pp.261-271
    • /
    • 1997
  • This paper presents the design process and characteristic test results of tension sensors for measuring the ultimate tension forces of surgical wires. Three types of sensor were designed and tested for calibration. The first two types which transfer the wire tension to the sensing element by direct contact have too much hysterisis errors due to the firctional effect. This error can be considerably reduced in the modified structure, where a cover and a loading button is used to transfer force and moment to the sensing element. The strains predicted by theoretical equations agree well with those by finite element calculations neglecting friction and the strains by finite element analysis considering friction are in good agreement with those measured by four strain gages. The modified ring type tension sensor developed in this paper is expected to be useful for measuring the tension of surgical wires with nonlinearity of 1.31%FS, hysterisis of 5.74%FS and repeatability of 0.19%FS.

$2({Y}_{3-x}Bi_x)({Fe}_{5-y}Al_y)O_{12}$ 가네트의 x, y 변화에 따른 자기특성에 관한 연구 (A Study un the Magnetic Properties of $2({Y}_{3-x}Bi_x)({Fe}_{5-y}Al_y)O_{12}$ Garnet with the Variation of x, y Additions)

  • 홍기원;박권화;장경욱;이준웅
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1993년도 하계학술대회 논문집 B
    • /
    • pp.1134-1136
    • /
    • 1993
  • The mean grain size of sample decreases with increasing the addition of $Al_2O_3$ in the basic composition of YIG. It is mean that the addition of $Al_2O_3$ is helpless the development of magnetic properties in YIG garnet, considering the relation of ${\mu}{\propto}D^{1/3}$. To increase addition of $Al_2O_3$ decreased the area of hysterisis loop. It is known that the addition of $Al_2O_3$ is help the development of magnetic properties in YIG garnet, considering the relation of loss component factor and the area of hysterisis loop. As a results, sample with the addition of $Al_2O_3$ 0.5 mol % among the fabricated samples is must effective in the magnetic properties of YIG Garnet.

  • PDF

반발식 자기 베어링의 응용으로서 고온 초전도체의 특성에 관한 실험적 연구 (An Experimental Study on the Characteristics of the High Temperature Superconductor as an Application of the Repulsive Type Magnetic Bearing)

  • 유제환;임윤철
    • Tribology and Lubricants
    • /
    • 제13권2호
    • /
    • pp.52-59
    • /
    • 1997
  • An experimental study is presented for the characteristics of the high temperature superconductor as an application of the repulsive type magnetic bearing. A ring shaped YBCO type superconductor and Neodium permanent magnets are employed for the experiment. For the case of field cooling, superconductor shows strong repulsive force, which is due to the Meissner effect, as the gap between the superconductor and the magnet gets closer. The repulsive force variation with respect to the gap change shows hysterisis characteristics. The area of the loop of the hysterisis curve represents the dissipation of energy, which reveals that the magnetic bearing with superconductor has large damping. The effect of the initial gap and the magnetic flux density on the repulsive force is analyzed experimentally and the static stiffness variation is calculated from the measured repulsive force variation. The relative sliding velocity between the superconductor and the magnet has little effect on the repulsive force which is quite different from the usual sliding element bearing. As the initial gap for the field cooling becomes larger, the maximum repulsive force at the minimum gap increases and approaches to the value for the case of zero field cooling.

토러스 형상 돌기의 흡착특성 유한요소해석

  • 조성산;양승민
    • 한국윤활학회:학술대회논문집
    • /
    • 한국윤활학회 2002년도 제35회 춘계학술대회
    • /
    • pp.179-184
    • /
    • 2002
  • Adhesive contact characteristics of torus-shaped bumps, which are commonly used to reduce friction and stiction in hard disks, are analyzed to examine the applicability to the MEMS structure. The analysis is conducted with the finite element technique considering the adhesive force. Torus-shaped bumps of various rim and bump radii are analyzed. The jump-to-contact behavior, adhesion hysterisis, pull-off forces, contact region and pressure, and surface and subsurface stresses are presented and discussed. Analysis results in the absence of adhesive force are also presented to identify the effect of adhesive force.

  • PDF

진동대 실험에 의한 RC부재의 이력거동 (Hysterisis Rules of RC member by Shaking Table Test)

  • 이대형;양동욱;백민철;홍현기;정영수
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
    • /
    • pp.9-10
    • /
    • 2009
  • 본 연구는 진동대 실험을 통하여 철근콘크리트 부재의 이력거동 모델을 규명하고자 한다. 부재의 이력거동은 지진과 같은 과도한 하중에 의한 부재의 안전성을 규명하는데 필수적이다. 질량에 따른 이력거동의 차이를 조사하였다.

  • PDF

Recent Trends on Wide-Viewing-Angle LC Modes and New Trials on CNT-LC System

  • Lee, Seung-Hee;Lee, Young-Hee
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
    • /
    • pp.101-104
    • /
    • 2005
  • Recently, competition between LC modes for LC TVs becomes high. In this paper, status of each mode is briefly reviewed with commenting on its electro-optic characteristics and possible application fields. Further, to understand effects of carbon nanotubes (CNTs) dispersed in nematic liquid crystal on electro-optic characteristic and orientation of the LC, CNT-doped NLC cells are made and evaluated. The hysterisis studies of voltage-dependent capacitance show that the amount of residual dc is greatly reduced due to ion trapping by CNTS.

  • PDF