• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.179-182
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• 1995

The NO$_2$gas-detection characteristics were investigated using the functional organic Langmuir-Blodgett(LB) films of Copper-tetra-tert-butylphthalocyanine(CuTBP). The optimum conditions for a film deposition were obtained through a study of $\pi$-A isotherms, and the deposited film status was confirmed by the ellipsometry measurements. It was found that at room temperature there are increments of electrical conductivities by 40 times, 25 seconds of response time and 40 seconds of response time when the films were exposed to the 200ppm NO$_2$gases. We hale observed an increase of the electrical conductivities as the density of NO2 gas increases.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.58-62
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• 1995

Thermally stimulated currents have been measured to investigate the trap characteristics of the MONOS structures with the tunneling oxide layer of 27${\AA}$ thick nitride layer of 73${\AA}$ thick and blocking oxide layer of 40${\AA}$ thick. By changing the write-in voltage and the write-in temperature, peaks of the I-T characteristic curve due to the nitride bulk traps and the blocking oxide-nitride interface traps ware separated from each other experimentally. The results indicate that the nitride bulk traps are distributed spatially at a single energy level and the blocking oxide-nitride interface traps are distributed energetically at interface.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.275-275
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• 2008

This paper describe the fabrication of a Pd/polycrystalline 3C-SiC schottky diode and its characteristics, in which the polycrystalline 3C-SiC layer and Pd Schottky contact were deposited by using APCVD and sputter, respectively. Crystalline quality, uniformity, and preferred orientations of the Pd thin film were evaluated by SEM and XRD, respectively. Pd/poly 3C-SiC Schottky diodes were fabricated and characterized by I-V and C-V measurements. Its electric current density Js and barrier height voltage were measured as $2\times10^{-3}$ A/$cm^2$ and 0.58 eV, respectively. These devices were operated until about $400^{\circ}C$. Therefore, from these results, Pd/poly 3C-SiC Schottky devices have very high potential for high temperature chemical sensor applications.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.11a
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• pp.118-121
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• 1994

The NO$_2$ gas-detection characteristics were investigated using the functional organic Langmuir-Blodgett(LB) film of Copper-tetra-tert-butylphalocyanine(CUTBP). The optimum conditions for a film deposition were obtained through a study of $\pi$-A isotherm and the deposited film status was confirmed by ellipsometry measurements. In the NO$_2$ response experiments, first of all, the proper number of layer was obtained by a change of the electrical conductivities depending on the number of layer when the film is exposed to the gas. And response time, recovery time, and reproducibility were measured on it. On the other hand, how the NO$_2$ gas interacts to the LB film was studied by UV/visible absorption spectra.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.415-418
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• 1998

The maleate copolyrner($C_{18}MA-VE_2$) is used as sensitive materials and deposited on the slide-glass substrates at room temperature using Langmuir-Blodgett(LB) method. The results of current-time(1-t) measurements are performed to investigate the gas-detection characteristics of the sensitive LB films in the presence of organic gases just as chloroform, acetone, ethanol, methanol using the apparatus for the gas-detection measurement. Several interesting responses are observed at room temperature, such as reversible response, sensitivity and response time. Response time and sensitivities are evaluated 160~220[sec], minimum 6[times], maximum 70[times] for each organic gas by adsorption and penetration of the organic gases in the relation concentration of 100[%], respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.05a
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• pp.79-82
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• 1994

We have manufacture Copper-tetra-tert-butylphalocyanine (CuTBP)Langmuir-Blodgett(LB) films, which is known be sensitive to NO$_2$ gab. A response of these films to the NO$_2$ gab was studied. A surface pleasure of 25mN/m was obtained as a proper one for a film deposition. A deposited film status was identified with Uv/visible absorption spectra, ellipsometry measurements, and current-voltage(I-Y) characteristics. The NO$_2$ gas response experiments under 200ppm conducentration show that there are increment of electrical conductivity by 12 times, 5 seconds of response time, and 5 seconds of response time, and 90 seconds of recovery time.

• Electrical & Electronic Materials
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• v.9 no.1
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• pp.51-58
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• 1996

This report describes thick traveling-wave electrode formation and microwave transmission characteristics of the fabricated electrodes. Effective refractive indices of the microwave in the 5 micron CPW type traveling-wave electrodes is around 2.45 according to the results of time domain S parameter measurements. The bandwidth of the electrodes is about 10 GHz and could be extended to 15 GHz through optimization of the process. The developed process technique that enables plating of micropatterns upto 20 micron can be applied to broadband optical intensity modulators.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.226-229
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• 2001

To achieve ZnO layer with a high resistance, a new sputtering method with a Ramp method and cycled power process mode was developed. The specific resistance of the layers was in rang of 3*10$\^$10/Ωcm to 2*10$\^$11/Ωcm. The characteristics of ZnO thin films changed with working pressure and Ramp method were investigated by XRD(x-ray diffractometer), and SEM (scanning electron microscopy) analyses. This paper presents calculated and measured results for structures with thin ZnO layers. Measurements of SAW Properties using thin ZnO layered structures will be shown. Also presented are results on the quality of ZnO films and specifics of the deposition process.

• Journal of Electrical Engineering and Technology
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• v.2 no.2
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• pp.145-151
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• 2007

Electric load components have different characteristics according to the variation of voltage and frequency. This paper presents the load modeling of an electric locomotive by the parameter identification method. The proposed method for load modeling is very simple and easy for application. The proposed load model of the electric locomotive is represented by the combination of the loads that have static and dynamic characteristics. This load modeling is applied to the KTX in Korea to verify the effectiveness of the proposed method. The results of proposed load modeling by the parameter identification follow the field measurements very exactly.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.483-486
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• 1999

The treeing inhibitors of barbituric acid derivatives and azocompounds effects on the electrical properties of crosslinked low density polyethylene were investigated. The electrical treeing parameters for tree inception voltage, AC breakdown strength. volume resistivity, capacitance and dissipation factor at 1Mz and thermoluminescence measurements were discussed. From the results, 4- (4-nitrophenylazo) resorcinol among the treeing inhibitors was shown good insulation characteristics.