• Title, Summary, Keyword: TSDC

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A Study on the Thermally-Stimulated Displacement Current (TSDC) of the Organic Ultra-Thin Langmuir-Blodgett(LB) Films (Langmuir-Blodgett(LB) 유기 초박막의 열자격 변위 전류에 관한 연구)

  • ;;;M. lwamoto
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.11 no.8
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    • pp.581-586
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    • 1998
  • This paper describes athermally stimulated displacement current (TSDC) of arachidic acid(AA) and polyamic acid alkylamine salts(PAAS) Langmuir-Blodgett(LB) films, which is a precursor of polyimide(PI). The TSDC measurements of AA LB film were performed from temperature to about 11$0^{\circ}C$ at a rate of 0.2$^{\circ}C$/s inside a vacuum chamber for a reference. And the TSDC measurements PAAS LB film were performed from room temperature to about 25$0^{\circ}C$ and temperature was increased at the same rate as that of AA LB film. They show that there are TSDC peaks at about 7$0^{\circ}C$ in the arachidic acid LB films, and at about 7$0^{\circ}C$ and 16$0^{\circ}C$ in the PAAs LB films. Results of these measurements indicate the one small peak at 7$0^{\circ}C$ is resulted from a softening of the alkyl group and the large peak at 16$0^{\circ}C$ is possibly due to dipole of C-O group in the PASS molecule. We have calculated the vertical component of the AA and PAAs L film out of the TSDC curves. It shows that the dipole moment of the AA LB film is about 70-mD at 7$0^{\circ}C$. And the dipole moment of PAAS LB film is about 040mD at 7$0^{\circ}C$ and about 200mD at 16$0^{\circ}C$ in the first measurement of TSDC. In the second measurement of TSDC of PASS LB film after cooling down to room temperature, the TSDC peaks are almost disappeared.

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Study on Polarization Properties of BaTiO3by Using Thermally Stimulated Depolarization Current (열자극 탈분극전류 방법에 의한 BaTiO3의 분극 특성 연구)

  • Song, Ho-Jun;Lee, Yong-Ryeol;Park, Yeong-Joon
    • Korean Journal of Materials Research
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    • v.12 no.8
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    • pp.613-616
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    • 2002
  • The polarization properties of $BaTiO_3$ were investigated by using thermally stimulated depolarization current (TSDC) technique. Two peaks were observed at about 400 K (peak A) and 435 K (peak B) from TSDC spectra obtained from the temperature range of 280-500 K. Peak A shows a sharp decrease of TSDC due to extinction of spontaneous polarization above the phase transition temperature of $BaTiO_3$. The values of activation energy of peak A and peak B were calculated to be 0.70 eV and 0.87 eV respectively. From the results of TSDC measurement with a variation of polarizing electric field strength, we found that saturation of total current of TSDC was started from 3kV/cm. However, the amount of total current of TSDC was not affected by the variation of polarizing time.

A Study of TSDC for Li2B4O7 Single Crystal (Li2B4O7 단결정의 TSDC에 관한 연구)

  • Cha, Jong Won
    • Journal of Korean Ophthalmic Optics Society
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    • v.3 no.1
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    • pp.269-277
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    • 1998
  • The TSDC(Thermally Stimulated Depolarization Current) measurement were carried out in the temperature range $30{\sim}500^{\circ}C$. We observed the anomalous two peaks that have a thousand times longer relaxation time than that of the space charge. It seems that the origin of the two peak are due to the electron trapping effect and to the adsorption of the vacancies at silver electrode.

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A study on the thermally-stimulated displacement current(TSDC) of the PAAS Langmuir-B1odgett(LB) films (PAAS LB 박막의 열자격 변위 전류에 관한 연구)

  • Lee, Ho-Sik;Kim, Sang-Keol;Song, Min-Jong;Choi, Myung-Kyue;Lee, Won-Jae;Kim, Tae-Wan;Kang, Dou-Yol
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • pp.11-14
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    • 2000
  • This paper describes a thennally stimulated displacement current(TSDC) of polyamic acid alkylamine salts(PAAS) Langmuir-Blodgett(LB) films, which is a precursor of polyimide(PI). The TSDC measurements of PAAS LB film were performed from room temperature to about $250^{\circ}C$ and the temperature was increased at a rate of $0.2^{\circ}C/s$. This show that this is TSDC peaks at about $70^{\circ}C$ in the arachidic acid LB films, and at about $70^{\circ}C$ and $160^{\circ}C$ in the PAAS LB films. Results of this measurements indicate that one small peak at $70^{\circ}C$ is resulted from a softening of the alkyl group and the large peak at $160^{\circ}C$ is possibly due to dipole moment of C-O group in the PAAS molecule. We have calculated the vertical component of dipole moment of the P AAS LB film out of the TSDC curves. It shows that the dipole moment of PAAS LB film is about -40mD at $70^{\circ}C$ and about 200mD at $160^{\circ}C$ in the first measurement of TSDC. In the second measurement of TSDC of PAAS LB film after cooling down to room temperature, the TSDC peaks are almost disappeared.

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Thermally Stimulated Depolarization Current Test for Reliability of X5R MLCC (TSDC 방법을 이용한 X5R MLCC의 신뢰성 평가)

  • Park, Ji-Young;Park, Jae-Sung;Kim, Young-Tae;Hur, Kang-Heon
    • Journal of the Korean Ceramic Society
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    • v.46 no.2
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    • pp.155-160
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    • 2009
  • The reliability could be one of the essential properties for multilayer ceramic capacitor (MLCC) using in various electronic devices and the concentration and mobility of oxygen vacancy would play important role in the reliability. To investigate the migration behavior of oxygen vacancies, thermally stimulated depolarization current (TSDC) is adopted. In dielectric material of X5R MLCC, the TSD-Current peak observed around 150$^{\circ}C$ and 200$^{\circ}C$ which represented the migration of oxygen vacancy. Substituting Yttrium for Dysprosium in X5R MLCC showed higher migration activation energy and lower TSD current density.

Thermal Stimulated Conductivity in Cellulose Triacetate-Multiwalled Carbon Nanotube Polymer Films

  • Basavaraja, C.;Jo, Eun-Ae;Kim, Bong-Sung;Huh, Do-Sung
    • Bulletin of the Korean Chemical Society
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    • v.31 no.8
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    • pp.2207-2210
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    • 2010
  • This paper describes the preparation and study of thermally stimulated discharge conductivity (TSDC) study of cellulose triacetate (CTA) - multiwalled carbon nanotubes (MWNTs) film thermoelectrets. TSDC has been carried out in the temperature range 308 - 503 K and at four different polarizing fields. The conductivity of the polymer blends increased with increase in temperature showing a semi-conducting behavior. The apparent activation energy also showed a pronounced effect with the increase in the content of MWNTs.

Depolarization Mechanism of Alternating-current-poled Pb(Mg1/3Nb2/3)O3-PbTiO3 Single Crystals Measured using in-situ thermally Stimulated Depolarization Current (TSDC 방법을 이용한 AC 폴링된 PMN-PT 단결정의 디폴링 메커니즘 분석)

  • Lee, Geon-Ju;Kim, Hwang-Pill;Lee, Sang-Goo;Lee, Ho-Yong;Jo, Wook
    • Journal of Sensor Science and Technology
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    • v.29 no.1
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    • pp.59-62
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    • 2020
  • Currently, increasing attention is being paid to relaxor-based ferroelectric single crystals in photoacoustic images, especially for high-end applications. Among the crystals are (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-100xPT) single crystals located near their morphotropic phase boundary (x = 0.30-0.35) because of their ultrahigh piezoelectric and electromechanical coupling properties. The alternating current poling (ACP) treatment, rather than the conventional direct current poling treatment, has recently been spotlighted due to its effectiveness in enhancing the piezoelectric properties. So far, it has been suggested that the enhanced piezoelectricity originates from either a domain miniaturization to nanodomains or from an electric-field-induced monoclinic symmetry. In this study, we demonstrate by thermally stimulated depolarization current measurements that the effect of ACP is too complex to be explained using a single mechanism and that the proposed electric-field-induced monoclinic symmetry is unlikely to exist.