• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.2
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• pp.175-182
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• 1990

In order to investigate the conduction characteistics of the biaxially oriented polypropylene film, several measurements have been carried out in the range of temperature between 5['c] and 25['c] as well as the field intensity between 10[MV/m] and 300[MV/m]. The whole range of the characteristics observed at 15['c] appears to be divided into five regions` the Ohmic conduction region due to ionic carrier below 40[MV/m], the region from 40[MV/m] to 70[MV/m] in which the conduction mechanism is attributed to Poole-Frenkel effect, the region from 70[MV/m] to 82[MV/m] in which the negative resistance characteristics are observed, then the region from 82[MV/m] which is dominated by Schottky effect and finally, the region from 240[MV/m] up to the point where dielectric breakdown occurs in which the mechanism is based on Flowler-Nordheim theory.

• Electrical & Electronic Materials
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• v.10 no.9
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• pp.945-951
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• 1997

Inorder to investigated electrical conduction characteristics of silicone oils due to viscosity variation we studied the electrical conduction properties at temperature range of 10~110[$^{\circ}C$] and electrical field from 1 to 1.33$\times$10$^4$[V/cm] The viscosity of used specimens was low viscous(1, 2, 5[cSt]) silicone oils. It was shown the ohmic conduction characteristics in low temperature and low field by Ion dipole and humidity included specimen. And we known the conduction mechanism due to electron injection by Schottky's effect in the high temperature an d high field region.

• Korean Journal of Materials Research
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• v.24 no.3
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• pp.140-144
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• 2014

The contact mechanism of devices is usually researched at electrode contacts. However, the contact between a dielectric and channel at the MOS structure is more important. The graphene was used as a channel material, and the thin film transistor with MOS structure was prepared to observe the contact mechanism. The graphene was obtained on Cu foil by the thermal decomposition method with $H_2$ and $CH_4$ mixed gases at an ambient annealing temperature of $1000^{\circ}C$ during the deposition for 30 min, and was then transferred onto a $SiO_2/Si$ substrate. The graphene was doped in a nitrogen acidic solution. The chemical properties of graphene were investigated to research the effect of nitric atoms doping. The sheet resistance of graphene decreased after nitrogen acidic doping, and the sheet resistance decreased with an increase in the doping times because of the increment of negative charge carriers. The nitric-atom-doped graphene showed the Ohmic contact at the curve of the drain current and drain voltage, in spite of the Schottky contact of grapnene without doping.

• Korean Journal of Materials Research
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• v.33 no.6
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• pp.229-235
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• 2023

An all-perovskite oxide heterostructure composed of SrSnO₃/Nb-doped SrTiO₃ was fabricated using the pulsed laser deposition method. In-plane and out-of-plane structural characterization of the fabricated films were analyzed by x-ray diffraction with θ-2θ scans and φ scans. X-ray photoelectron spectroscopy measurement was performed to check the film's composition. The electrical transport characteristic of the heterostructure was determined by applying a pulsed dc bias across the interface. Unusual transport properties of the interface between the SrSnO₃ and Nb-doped SrTiO₃ were investigated at temperatures from 100 to 300 K. A diodelike rectifying behavior was observed in the temperature-dependent current-voltage (IV) measurements. The forward current showed the typical IV characteristics of p-n junctions or Schottky diodes, and were perfectly fitted using the thermionic emission model. Two regions with different transport mechanism were detected, and the boundary curve was expressed by ln I = -1.28V - 13. Under reverse bias, however, the temperature- dependent IV curves revealed an unusual increase in the reverse-bias current with decreasing temperature, indicating tunneling effects at the interface. The Poole-Frenkel emission was used to explain this electrical transport mechanism under the reverse voltages.

• Journal of the Korean Ceramic Society
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• v.55 no.3
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• pp.244-260
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• 2018

Issues in the electrical characterization of semiconducting photoanodes in a photoelectrochemical (PEC) cell, such as the cell geometry dependence, scan rate dependence in DC measurements, and the frequency dependence in AC measurements, are addressed, using the example of a $TiO_2$ photoanode. Contrary to conventional constant phase element (CPE) modeling, the capacitive behavior associated with Mott-Schottky (MS) response was successfully modeled by a Havriliak-Negami (HN) capacitance function-which allowed the determination of frequency-independent Schottky capacitance parameters to be explained by a trapping mechanism. Additional polarization can be successfully described by the parallel connection of a Bisquert transmission line (TL) model for the diffusion-recombination process in the nanostructured $TiO_2$ electrode. Instead of shunt CPEs generally employed for the non-ideal TL feature, TL models with ideal shunt capacitors can describe the experimental data in the presence of an infinite-length Warburg element as internal interfacial impedance - a characteristic suggested to be a generic feature of many electrochemical cells. Fully parametrized impedance spectra finally allow in-depth physicochemical interpretations.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.36 no.6
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• pp.418-423
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• 1987

In the course of the investigation to the field dependent electrical conducation mechanism in polypropylene, an abnormal conduction phenomena such as voltage controlled negative resistance charateristics has been observed at the junction of two regions charateriged by schottky effect and space charge effect respectively. This abnormal characteristics was observed initially about 110MV / m of the field strength and at 25 , however, the field strength where it observed was decreased and the apparent feature of negative charateristics was less pronounced as increasing ambient temperature. Although the observations of analogous characteristics in other materials such as polyethylene, polymethylemethactylate, and polystyrene have already been reported together with plausible explanation by Toureille and others, however, it was found that the proposed concept by those authors was little use to the present observations for quantitative discussions. Accordingly we tried to adapt another conceptual discussion based on Gibbons's formulation pertaing to the saturatio trend of the field dependent drift velocity of carriers towards the thermal velocity corresponding to the ambient temperature so that the quantitative explanatio on the observed facts has been succeeded to some estent of reasonable acceptance.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.729-732
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• 2001

In this study, the effect of oxygen partial pressure on the electrical properties of vanadium oxide(VO$_{x}$) thin films were investigated. The thin films were prepared by r.f. magnetron sputtering from V$_2$O$_{5}$ target in a gas mixture of argon and oxygen. The oxygen partial pressure ratio is changed from 0% to 8%. I-V characteristics were distinguished between linear and nonlinear region. In the low field region the conduction is due to Schottky emission, while at high fields it changes to Fowler-Nordheim tunneling type conduction. The conductivity measurements have shown an Arrhenius dependence of the conductivity on the temperature.ure.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.30A no.1
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• pp.44-50
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• 1993

In an attempt to improve the electrical characteristics of tantalum pentoxide dielectric film, silicon substrate was reacted with a nitrogen plasma to form a silicon nitride of 50.angs. and then tantalum pentoxide thin films were formed by reactive sputtering in the same chamber. Breakdown field and leakage current density were measured to be 2.9 MV/cm and 9${\times}10^{8}\;A/cm^{2}$ respectively in these films whose thickness was about 180.angs.. With annealing at rectangular waveguides with a slant grid are investigated here. In particular, 900.deg. C in oxygen ambient for 100 minutes, breakdown field and leakage current density were improved to be 4.8 MV/cm and 1.61.6${\times}10^{8}\;A/cm^{2}$ respectively. It turned out that the electrical characteristics could also be improved by oxygen plasma post-treatment and the conduction mechanism at high electric field proved to be Schottky emission in these double-layered films.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1636-1638
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• 1996

MMA-Styrene-Tetramethyltin(MST) thin films were fabricated by plasma polymerization method, and their electrical properties were confirmed by IR and GPC. The electrical conductivity increased with increasing temperature, and the adsorption current hardly appeared. The high-field electrical conduction mechanism is the electronic one such as schottky, and the activation energy is about 1.1 eV.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.5
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• pp.489-495
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• 1991

In this paper, we study the electrical conduction mechanism in Langmuir-Blodgett(LB) ultra thin films for which the LB device has a metal/LB films(TCNQ)/metal sandwich structure. Our experiments show that the current at the LB device does not depend on the temperature at below 0 C. This phenomena confirm that the electrical conduction current is a tunnel current inherent to ultra thin films. However, the current depends upon the temperature near the room temperature. This phenomena indicates the electeical conduction current is a Schottky current inherent to ultra thin films.