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Publications (4)0.48 Total impact

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    ABSTRACT: In this paper, the photo-stimulated discharge (PSD) current spectra of polyimide (PI) are obtained by the optical parametric oscillator (OPO) laser to characterize the deep space charge traps in the dielectric materials. The result shows that the energy level of charge traps in the PI film is distributed in 3.10~4.10eV, and the main part concentrates in 3.35~3.85eV. These data can provide experimental basis for the further research and improvement on electrical properties of materials.
    01/2010;
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    ABSTRACT: A photo-stimulated discharge (PSD) method is more effective than thermal methods to characterize the deep space charge traps in dielectric materials. In this paper, a new PSD measuring system was first built up based on the optical parametric oscillator laser. The laser can generate continuously tunable wavelengths whose range are 210-420 nm and with average output pulse energy 2.3 mJ. The system overcomes the shortcoming of weak output energy in past experiments, especially in the range of ultraviolet band. The PSD current spectra of PET were measured by this system. The results show that the energy level of charge traps in the PET film is mainly distributed in 4.08~5.18 eV, and the trap density maximum is at 4.22 eV. These data can provide the experimental basis for further research and improvement on electrical properties of materials.
    Modern Physics Letters B 01/2010; 24(18):1933-1941. · 0.48 Impact Factor
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    ABSTRACT: Photo-stimulated discharge (PSD) spectroscopy of polyester (PET), polypropylene (PP), polyimide (PI) of DuPont charged by either corona discharge or contact electrode were performed with self-made PSD measurement system in order to investigate the space charge traps of the polymers. The samples were irradiated with new type of continuously tunable wavelength laser based on the optical parametric oscillator (OPO) through the semi-transparent electrode. Experimental results indicate that the energy distribution of traps varies with different materials: there exists only one single trap energy level to be activated by OPO laser in PET, however, broad peaks spectrum in PI and PP. In the meanwhile some of deep trap are ascribed to factors like additives such as cross-linking agent. The effect of molecular motions on thermal erosion of the traps was also investigated.
    Properties and Applications of Dielectric Materials, 2009. ICPADM 2009. IEEE 9th International Conference on the; 08/2009
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    ABSTRACT: Photo-stimulated discharge (PSD) is an effective method to characterize the deep traps in the dielectric materials. In this paper, a new PSD measuring system was firstly built up based on the optical parametric oscillator laser. The laser can generate continuously tunable wavelength output light of which wavelength range is 210-420 nm and average output pulse energy is 2.3 mJ. The system overcomes the shortcoming of weak output energy in the experiments before, especially in the range of ultraviolet band. Experiments proved that this PSD system can work well and can be widely used in the theoretical and practical research of the dielectric materials.
    01/2009;