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ER, N., D. CJ, L. MC, I. R, I. P, and M. - M. JN, On the width of the thermally stimulated discharge current peak, , Jan, 2010. Abstract
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ER, N., D. CJ, L. MC, I. R, I. P, and M. - M. J. N., The use of the final thermally stimulated discharge current technique to study the molecular movements around glass transition, , vol. 354, issue 2, 2011. Abstract

During electric polarization charge is injected into the material. The structure is decorated with space charge and during the subsequent heating an apparent peak and the genuine peaks that are related to dipole randomization and charge detrapping are observed. The method is used here to analyze the molecular movements in polyimide in the temperature range from 293 to 623K. Two weak relaxations have been observed around 337K and around 402K. The electrical conductivity changes with temperature in agreement with the Arrhenius law only below (W=(0.84±0.03) eV ) and above ( W=(0.82±0.03) eV) the temperature range where the β relaxation is observed. The variation of the electrical conductivity with temperature, in the range of the β relaxation, is controlled by the variation of the charge currier mobility with temperature and it shows a non-Arrhenius behavior. We suggest that the β1 sub-glass relaxation is related to the rotation or oscillation of phenyl groups and the β2 sub-glass relaxation is related to the rotation or oscillation of the imidic ring. At higher temperatures an apparent peak was observed. The relaxation time of the trapped charge, at 573K, is high than 8895s.

ER, N., N. RM, D. CJ, L. MC, I. P, and M. - M. JN, Electrical Method to Study the Weak Molecular Movements at Nanometric Scale in Low Mobility Materials, , vol. 636-637, pp. 430-436, Jan, 2010. Abstract
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ER, N., D. CJ, L. MC, I. R, I. P, and M. - M. JN, The study of the molecular movements in the range of glass transition by the final thermally stimulated discharge current technique, , Jan, 2010. Abstract
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ER, N., D. CJ, L. MC, I. R, I. P, and M. - M. JN, "Charge Carriers Injection/Extraction at the Metal-Polymer Interface and Its Influence in the Capacitive Microelectromechanical Systems-Switches Actuation Voltage", JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY, vol. 10: Univ Nova Lisboa, pp. 2503-2511, Jan, 2010. Abstract
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ER, N., D. CJ, L. MC, I. R, and M. - M. JN, Medium Electric Field Electron Injection/Extraction at Metal-Dielectric Interface, , no. 636-637, pp. 437-443, Jan, 2010. Abstract
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ER, N., D. CJ, L. MC, I. R, I. P, and M. - M. J. N., The use of the final thermally stimulated discharge current technique to study the molecular movements around glass transition, , vol. 354, pp. 385-390, Jan, 2011. Abstract
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ER, N., N. RM, D. CJ, L. MC, and M. - M. JN, "The determination of the metal-dielectric interface barrier height from the open-circuit isothermal charging current", Journal of Applied Physics, vol. 104, Jan, 2008. AbstractWebsite
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ER, N., D. CJ, L. MC, I. R, and M. - M. JN, Medium Electric Field Electron Injection/Extraction at Metal-Dielectric Interface, , vol. 636-637, pp. 437-443, Jan, 2010. Abstract
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