• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 1996년도 추계학술대회 논문집
• /
• pp.199-202
• /
• 1996

This paper describes the thermally stimulated current (TSC) measurements of arachidic acid and polyamic acid alkylamine salt(PAAS) LB film, which is a precursor of polyimide(PI). The measurements were performed from room temperature to about 25$0^{\circ}C$ and the temperature was increased at a rate of 0.02 K/s linearly. It shows that peaks of TSC are observed at about 8$0^{\circ}C$ in the arachidic acid and about 8$0^{\circ}C$, 16$0^{\circ}C$ in the PAAS LB films. Results of these measurements indicate that one peak at 8$0^{\circ}C$ is resulted from alkyl group; the other peak at 16$0^{\circ}C$ is due to alkyl and C-O group of PAAS. Additional large peak at about 16$0^{\circ}C$ is due to dipole moments in the PAAS films. The DSC and TGA of PAAS, arachidic acid and octadesylamine are measured. Thermal imidization was performed at 30$0^{\circ}C$ far 1 hour by our pre study

• E2M - 전기 전자와 첨단 소재
• /
• 제8권6호
• /
• pp.759-767
• /
• 1995

This paper examines the electrical properties according to a curing time and a corona degradation in epoxy composites which are used for transformers. To consider these phenomena, the electrets were formed by appling high voltages to five kinds of specimens designed according to a constant mixing rate and then TSC(Thermally Stimulated Current) values at the temperature range of -160-200[>$^{\circ}C$] were measured from a series of experiments. The behaviour of carrier and its possible origins in epoxy composites were studied. Various effects of curing time and electric field on epoxy composites were also investigated.

• 대한전기학회논문지
• /
• 제41권2호
• /
• pp.185-191
• /
• 1992

In this paper, it is attempted to distinguish the charged particles and to judge the polarity by the use of Thermally Stimulated Current(TSC) and Temperature Gradient Thermally Stimulated Surface Potential Measurement(TG-TSSP)with experimental insulation material XLPE-EVA for power cables which is made by blending cross-linked polyethylene(XLPE) and ethylene-vinylacetate copolymer(EVA). In addition, it is performed to investigate the effect of EVA blending. From the experimental results, it is known that for the case of XLPE-EVA blended experimental material, the generation of space charged electric field is not obtained in the high temperature region due to the obatruction of the injection of trapping carrier by the electron and the positive hole.

• 대한전기학회논문지
• /
• 제40권8호
• /
• pp.808-815
• /
• 1991

The behavior of space charge in PE/ionomer blends has been investigated using the thermally stimulated current (TSC) technique. In the blends, at least two TSC peaks over the temperature range from -50 to 100\ulcorner are observed, one at -5 ~ 10\ulcorner (a peak) and the others at above 60\ulcorner (a peak). The a peak is assigned as the orientation of dipoles from the ionomer component. Two a peaks seem to be related to the charge trapping at sites related to the crystalline phases. One a peak is associated with the ionic interfaces and the other with the ethylene chains without the ionic interfaces. The amount of charges stored in PE/Surlyn 1652 blends increases as the poling field increases over the field range of +8 ~ +30 kV/mm, whereas that in PE/Surlyn 1601 blends increases slightly at low poling fields and then decreases at high poling fields above +10 kV/mm. Exact reasons for such a dirrerence are not known at this point.

• E2M - 전기 전자와 첨단 소재
• /
• 제6권1호
• /
• pp.50-54
• /
• 1993

각종 monomer를 공중합시킨 PE의 고전계 전기전도와 X선 유기 TSC(X-ray induced thermally stimulated current)를 측정하고 공중합 monomer의 영향에 대하여 검토하였다. 할로겐을 함유한 공중합 PE에서 고전계 전기전도가 억제되는 것을 관찰하였다. 또 할로겐을 함유하는 monomer를 공중합시킨 PE의 X선 유기 TSC에서는 공중합에 의한 전자 trap은 약 0.4eV정도로 평가된다. 이들 시료에서 절연 파괴 강도가 상승한 것은 전자 트랩이 전자의 전계가속을 억제하여 고전계 전기전도를 억제시키고 절연파괴강도를 향상 시킨 것으로 추측된다.

• 한국진공학회지
• /
• 제8권3A호
• /
• pp.187-193
• /
• 1999

In this study, PVDF thin films which show the excellent piezoelectricity and pyroelectricity, are prepared by PVD (physical vapor deposition) method, and thir electrical conduction phenomena for analyses of the electrical conduction mechanism and TSC (Thermally Stimulated Current) for identification of the behavior of conductive carriers are investigated. As a result of FT-IR(Fourier Transform Infrared Spectroscopy) spectra, the crystalline phase transforms $\alpha$ type into $\beta$ type with increasing electric field. From XRD (X-Ray diffraction) analyses patterns, the degree of crystallinity increases from 49.8% to 67%, as the substrate temperature increases from $30^{\circ}C$ to $80^{\circ}C$. As a result of electrical conduction phenomena, the electrical conduction mechanism of PVDF thin films is identified as ionic conduction mechanism. From TSC analyses, there are three peaks as P1, P2, P3 with increasing temperature, and with increasing substrate temperature, the peak temperature of TSC increases and the peak intensity of TSC decreases.

• E2M - 전기 전자와 첨단 소재
• /
• 제7권5호
• /
• pp.383-388
• /
• 1994

Deep levels in semi-insulating GaAs were observed by thermally stimulated current(TSC) measurement In the temperature ranges of 100-300K Tl(E$\_$c/-0.18eV), T2(E$\_$c/-0.20eV), T3(E$\_$c/-0.31eV), T4(E$\_$c/-0.40eV), and T5(E$\_$c/-O.43eV) traps have been observed. The TI, T2, and T5 traps seem to be related to the V$\_$As/, V$\_$Ga/-complex, and As$\_$Ga/$\^$++/ respectively. T4 trap is considered with respect to V$\_$Ga/-V$\_$As/ complex.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2000년도 제2회 학술대회 논문집 일렉트렛트 및 응용기술전문연구회
• /
• pp.68-72
• /
• 2000

In order to estimate spatial charging process in the corona charging which has been used to make polymer electret, the electrical properties of polypropylene film were obtained from Thermally Stimulated Current (TSC) measurements after corona charging between knife electrode and cylinder electrode with the voltages of -5, -6, -7 and -8[kV], respectively. And then the electrostatic contour and the electric field vector were also simulated by using Finite Element Method (FEM). The edge effect around edge of knife electrode affected the electrostatic contour on surface of specimen and the electric field concentration inside specimen. The uneven charging state in the electret due to the mistake on design could be calculated and so the optimal design of corona charging device which is appropriate to various materials is come to be practicable.

• 한국안전학회지
• /
• 제11권2호
• /
• pp.60-66
• /
• 1996

In order to look into the internal structure and electrical properties of insulating Silicone rubbers added reinforcing fillers ; Silica(0-140 phr ), and to examine the behavior of charged particles, and the properties of thermally stimulated current (TSC) are investigated, respectively. From the TSC which are formed by applying the electric field of 2~5 ㎸/mm to specimen at temperature range from -150 to $270^{\circ}C$, the results arp as following. In the case of non-filled specimen, four peaks of $\delta$, $\gamma$ , $\beta$ and u are obtained at the temperature of $-120^{\circ}C$, $-60^{\circ}C$, $20^{\circ}C$ and $130^{\circ}C$, respectively and the case of filled specimen, three peaks of $\delta$, ${\alpha}_2$ and ${\alpha}_1$ are observed at the temperature of of $-120^{\circ}C$, $80^{\circ}C$ and $130^{\circ}C$, respectively. The origins of these peaks are that, the $\delta$ peak seems to the result from the contribution of side chain methyl radical, and the $\beta$ peak from the depolarization of space charge polarization owing to added imputity during during manufacturing specimens, and the $\beta$ peak from the orientation of $Si-CH_3$dipole, and the ${\alpha}_2$ near the temperature of $130^{\circ}C$ from carboxyl acid that is formed by the thermal oxidation of high temperature.

• E2M - 전기 전자와 첨단 소재
• /
• 제9권4호
• /
• pp.396-403
• /
• 1996

In this paper, the (S $r_{0.85}$.C $a_{0.15}$)Ti $O_{3}$ of paraelectric grain boundary layer (GBL) ceramics were fabricated, and the analysis of microstructuye and the thermally stimulated current(TSC) were investigated for understanding effects of GBL's interfacial phenomenon on variations of electrical properties. As a result, the three peaks of .alpha., .alpha. and .betha. were obtained at the temperature of -20 [.deg. C], 20[.deg. C] and 80[.deg. C], respectively. The origins of these peaks are that the .alpha. peak observed at -20[.deg. C] looks like to be ascribed to the ionization excitation from donor level in the grain, and the .alpha.' peak observed at 20[.deg. C] appears to show up by detrap of the trapped carrier of border between the oxidation layer and the grain, and the .betha. peak observed at 80[.deg. C] seems to be resulted from hopping conduction of existing carrier in the trap site of the border between the oxidation and second phase. and second phase.