• 제목/요약/키워드: I-V measurements

검색결과 353건 처리시간 0.028초

실루엣에 의한 한국여성의 체형분석 (A Study on the Classification of the Somatotype of Korean Females)

  • 남윤자;이순원
    • 한국의류학회지
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    • 제8권1호
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    • pp.47-56
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    • 1984
  • The purpose of this study was to classify somatotype and to investigate the 15 measurements for the clothing construction. The size of sample was 467 females between age 6 and 60. Analysis of Variance (ANOVA) was employed to analyze the 15 measurements by group and somatotype. The results of the study were as follows; 1) All the measurements were significantly different among the groups except the Vertebralis angle. 2) Concerning the upper part of the body, Standard somatotype was found more frequently in group IV. V compared with the other, Turning over somatotype in group I. II, Bending somatotype in group VI. VII. VIII. Concerning the under part of the body Standard somatotype was found more frequently in group IV. V. VI. VII. VIII. compared with the other, Forward-turning over somatotype of the lower help body and Turning over somatotype in group I. II. III. when the upper part of the body was turning over somatotype, the under part of the body was generally Turning over somatotype or Forward-turning over somatotype. When the upper part of the body was Bending somatotype, the under part of the body was commonly Forward somatotype.

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Comparative Measurements and Characteristics of Cu Diffusion into Low-Dielectric Constant para-xylene based Plasma Polymer Thin Films

  • Kim, K.J.;Kim, K.S.;Jang, Y.C.;Lee, N.-E.;Choi, J.;Jung, D.
    • 한국표면공학회지
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    • 제34권5호
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    • pp.475-480
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    • 2001
  • Diffusion of Cu into the low-k para-xylene based plasma polymer (pXPP) thin films deposited by plasma-enhanced chemical vapor deposition using the para-xylene precursor was comparatively measured using various methods. Cu layer was deposited on the surfaces of pXPPs treated by $N_2$ plasma generated in a magnetically enhanced inductively coupled plasma reactor. Diffusion characteristics of Cu into pXPPs were measured using Rutherford backscattering spectroscopy (RBS), secondary ion mass spectroscopy (SIMS), cross-sectional transmission electron microscopy (XTEM), and current-voltage (I-V) measurements for the vacuum-annealed Cu/pXPPs for 1 hour at $450^{\circ}C$ and were compared. The results showed a correlation between the I-V measurement and SIMS data are correlated and have a sensitivity enough to evaluate the dielectric properties but the RBS or XTEM measurements are not sufficient to conclude the electrical properties of low-k dielectrics with Cu in the film bulk. The additional results indicate that the pXPP layers are quite resistant to Cu diffusion at the annealing temperature of $450^{\circ}C$ compared to the other previously reported organic low-k materials.

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비정질 실리콘을 이용한 다층 유전 박막의 전기적 특성에 관한 연구 (Study on Electric Charactreistics of Multi-dielectric Thin Films Using Amorphous Silicon)

  • 정희환;정관수
    • 한국진공학회지
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    • 제3권1호
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    • pp.71-76
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    • 1994
  • The electrical characteristics of the capacitor dielectric films of amorphous silicon-nit-ride-oxide(ANO) structures are compared with the capacitor dielectric films of oxide-nitride-oxide (ONO) structrues The electrical characteristics of ONO and ANO films were evaluated by high frequency(1 MHz) C-V high frequency C-V after constant voltage stree I-V TDDB and refresh time measurements. ANO films shows good electrical characteristics such as higher total charge to breakdown storage capacitance and longer refresh time than ONO films. Also it makes little difference that leakage current and flat band voltage shyift(ΔVfb)of ANO ana ONO films.

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Numerical Simulation on Self-heating for Interlayer Tunneling Spectroscopy in $Bi_2Sr_2CaCu_2O_{8+x}$

  • Park, Jae-Hyun;Lee, Hu-Jong
    • Progress in Superconductivity
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    • 제9권1호
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    • pp.18-22
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    • 2007
  • For interlayer tunneling spectroscopy using a small stack of $Bi_2Sr_2CaCu_2O_{8+x}$ (Bi-2212) intrinsic junctions in a high-bias range, large self-heating takes place due to the poor thermal conductivity of Bi-2212. In this study, we numerically estimate the self-heating around a Bi-2212 sample stack for I-V or dI/dV-V measurements. Our results show that the temperature discrepancy between the Bi-2212 sample stack and top Au electrodes due to bias-induced self-heating is small enough along the c-axis direction of Bi-2212. On the other hand, the lateral temperature discrepancy between the sample stack and the Bi-2212 on-chip thermometer stack can be as large as ${\sim}20\;K$ for the highest bias required to observe the pseudogap hump structure. We thus suggest a new in-situ ac thermometry, employing the Au current-bias electrode itself deposited on top of the sample stack as the resistive thermometer layer, which is supposed to allow safe temperature measurements for the interlayer tunneling spectroscopy.

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Light I-V 곡선을 이용한 결정질 태양전지의 이상계수와 직렬 저항 특성 분석 (Use of a Transformed Diode Equation for Characterization of the Ideality Factor and Series Resistance of Crystalline Silicon Solar Cells Based on Light I-V Curves)

  • 정수정;김수민;강윤묵;이해석;김동환
    • 한국재료학회지
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    • 제26권8호
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    • pp.422-426
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    • 2016
  • With the increase in installed solar energy capacity, comparison and analysis of the physical property values of solar cells are becoming increasingly important for production. Therefore, research on determining the physical characteristic values of solar cells is being actively pursued. In this study, a diode equation, which is commonly used to describe the I-V behavior and determine the electrical characteristic values of solar cells, was applied. Using this method, it is possible to determine the diode ideality factor (n) and series resistance ($R_s$) based on light I-V measurements. Thus, using a commercial screen-printed solar cell and an interdigitated back-contact solar cell, we determined the ideality factor (n) and series resistance ($R_s$) with a modified diode equation method for the light I-V curves. We also used the sun-shade method to determine the ideality factor (n) and series resistance ($R_s$) of the samples. The values determined using the two methods were similar. However, given the error in the sun-shade method, the diode equation is considered more useful than the sun-shade method for analyzing the electrical characteristics because it determines the ideality factor (n) and series resistance ($R_s$) based on the light I-V curves.

Characteristics of Insulation Diagnosis and Failure in Gas Turbine Generator Stator Windings

  • Kim, Hee-Dong
    • Journal of Electrical Engineering and Technology
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    • 제9권1호
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    • pp.280-285
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    • 2014
  • In order to evaluate the insulation deterioration in the stator windings of five gas turbine generators(137 MVA, 13.8 kV) which has been operated for more than 13 years, diagnostic test and AC dielectric breakdown test were performed at phases A, B and C. These tests included measurements of AC current, dissipation factor, partial discharge (PD) magnitude and capacitance. ${\Delta}I$ and ${\Delta}tan{\delta}$ in all three phases (A, B and C) of No. 1 generator stator windings showed that they were in good condition but PD magnitude indicated marginally serviceable and bad level to the insulation condition. Overall analysis of the results suggested that the generator stator windings were indicated serious insulation deterioration and patterns of the PD in all three phases were analyzed to be internal, slot and spark discharges. After the diagnostic test, an AC overvoltage test was performed by gradually increasing the voltage applied to the generator stator windings until electrical insulation failure occurred, in order to determine the breakdown voltage. The breakdown voltage at phases A, B and C of No. 1 generator stator windings failed at 28.0 kV, 17.9 kV, and 21.3 kV, respectively. The breakdown voltage was lower than that expected for good-quality windings (28.6 kV) in a 13.8kV class generator. In the AC dielectric breakdown and diagnostic tests, there was a strong correlation between the breakdown voltage and the voltage at which charging current increases abruptly ($P_{i1}$, $P_{i2}$).

PACVD of Plasma Polymerized Organic Thin Films and Comparison of their Electrochemical Properties

  • I.S. Bae;S.H. Cho;Kim, M.C.;Y.H. Roh;J.H. Boo
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2003년도 춘계학술발표회 초록집
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    • pp.53-53
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    • 2003
  • Plasma polymerized organic thin films were deposited on Si(100) glass and metal substrates using thiophene and ethylcyclohexane precursors by PECVD method. In order to compare electrochemical properties of the as-grown thin films, the effects of the RF plasma power in the range of 30~100 W. AFM showed that the polymer films with smooth surface and sharp interface could be grown under various deposition conditions. Impedance analyzer was utilized for the determination of I-V curve for leakage current density and C-V for dielectric constants, respectively. To obtain C-V curve, we used a MIM structure of metal(Al)-insulator(plasma polymerized thin film)-metal(Pt) structure. Al as the electrode was evaporated on the thiophene films that grew on Pt coated silicon substrates, and the dielectric constants of the as-grown films were then calculated from C- V data measured at 1MHz. From the electrical property measurements such as I-V and C-V characteristics, the minimum dielectric constant and the best leakage current of thiophene thin films were obtained to be about 3.22 and $1{\;}{\times}10^{-11}{\;}A/cm^2$. However, in case of ethylcyclohexane thin films, the minimum dielectric constant and the best leakage current were obtained to be about 3.11 and $5{\;}{\times}10^{-12}{\;}A/cm^2$.

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태양전지의 단락전류 편차가 태양전지모듈에 미치는 전기적인 영향 분석 (The electrical effects of PV cell's short-circuit current difference for PV module application)

  • 김승태;박지홍;강기환;안형근;한득영;유권종
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.3-4
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    • 2008
  • Photovoltaic module consists of serially connected solar cell which has low voltage characteristics. But, the other way, the whole current flow of PV module is restricted by lowest current of one solar cell. For the experiment, we make PV module composing the solar cells that have short circuit current difference of 0%, 1%, 3% and 5%. Using Light I-V and Dark I-V measurements, electrical characteristic parameters like Isc(short-circuit current), Voc(open-circuit voltage), Rs(series resistance), Rsh(shunt resistance) are analyzed. PV module of low current characteristics has electrical stress from other modules. And, such a module has a tendency of hot-spot suffering which leads degradation.

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Influence of Series Resistance and Interface State Density on Electrical Characteristics of Ru/Ni/n-GaN Schottky structure

  • Reddy, M. Siva Pratap;Kwon, Mi-Kyung;Kang, Hee-Sung;Kim, Dong-Seok;Lee, Jung-Hee;Reddy, V. Rajagopal;Jang, Ja-Soon
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제13권5호
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    • pp.492-499
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    • 2013
  • We have investigated the electrical properties of Ru/Ni/n-GaN Schottky structure using current-voltage (I-V) and capacitance-voltage (C-V) measurements at room temperature. The barrier height (${\Phi}_{bo}$) and ideality factor (n) of Ru/Ni/n-GaN Schottky structure are found to be 0.66 eV and 1.44, respectively. The ${\Phi}_{bo}$ and the series resistance ($R_S$) obtained from Cheung's method are compared with modified Norde's method, and it is seen that there is a good agreement with each other. The energy distribution of interface state density ($N_{SS}$) is determined from the I-V measurements by taking into account the bias dependence of the effective barrier height. Further, the interface state density $N_{SS}$ as determined by Terman's method is found to be $2.14{\times}10^{12}\;cm^{-2}\;eV^{-1}$ for the Ru/Ni/n-GaN diode. Results show that the interface state density and series resistance has a significant effect on the electrical characteristics of studied diode.

회전 도포 공정을 이용한 Polymethyl methacrylate(PMMA) 박막의 열처리에 따른 전기적 특성 평가 (Electric properties of Polymethyl methacrylate(PMMA) Films to thermal treatment Prepared by Spin Coating)

  • 나문경;강동필;안명상;명인혜;강영택
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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    • pp.1924-1926
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    • 2005
  • Poly(methyl methacrylate) (PMMA) is one of the promising representive of polymer gate dielectric for its high resistivity and sutible dielectric constant. PMMA (Mw=96700) films were prepared on p-Si by spin coating method. PMMA were coated compactively and flatly as observes by AFM. MIS(Al/PMMA/p-Si) structure was made and capacitance-voltage (C-V) and current-voltage (I-V) measurements were done with PMMA films for repeated annealing cycles at $100^{\circ}C$. 1-V measured at various delay times $(0{\sim}20sec)$ showed little change and the absence of hysteresis in the I-V characteristics with delay times, which eliminate the possibility of deep traps in the PMMA films. The observed thermal stability, smooth surfaces, dielectric constant, I-V behavior implies PMMA formed by spin coating can be used as an efficient gate dielectric layer in OTFTs.

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