• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 1997년도 추계학술대회 발표논문집:21세기를 향한 정보통신 기술의 전망
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• pp.451-462
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• 1997

A 2-dimensional numerical analysis is presented for thermal-electron heat conduction effects upon the electron transport and the drain current-voltage characteristics of submicron GaAs MESFETs, based on the use of a nonstationary hydrodynamic transport model. It is shown that for submicron GaAs MESFETs, electron heat conduction effects are significant on their internal electronic properties and also drain current-voltage characteristics. Due to electron heat conduction effects, the electron energy is greatly one-djmensionalized over the entire device region. Also, the drain current decreases continuously with increasing thermal conductivity in the saturation region of large drain voltages above 1 V. However, the opposite trend is observed in the linear region of small drain voltages below 1 V. Accordingly, for a large thermal conductivity, negative differential resistance drain current characteristics are observed with a pronounced peak of current at the drain voltage of 1 V. On the contrary, for zero thermal conductivity, a Gunn oscillation characteristic is observed at drain voltages above 2 V under a zero gate bias condition.

• Journal of Electrochemical Science and Technology
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• 제12권1호
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• pp.1-20
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• 2021

In-depth knowledge of electrode processes is crucial for determining the electrochemical performance of lithium-ion batteries (LIBs). In particular, the conduction mechanisms of charged species in the electrodes, such as lithium ions (Li+) and electrons, are directly correlated with the performance of the battery because the overall reaction is dependent on the charge transport behavior in the electrodes. Therefore, it is necessary to understand the different electrochemical processes occurring in electrodes in order to elucidate the charge conduction phenomenon. Thus, it is essential to conduct fundamental studies on electrochemical processes to resolve the technical challenges and issues arising during the ionic and electronic conduction. Furthermore, it is also necessary to understand the transport of charged species as well as the predominant factors affecting their transport in electrodes. Based on such in-depth studies, potential approaches can be introduced to enhance the mobility of charged entities, thereby achieving superior battery performances. A clear understanding of the conduction mechanism inside electrodes can help overcome challenges associated with the rapid movement of charged species and provide a practical guideline for the development of advanced materials suitable for high-performance LIBs.

• 공업화학
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• 제22권1호
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• pp.26-30
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• 2011

염료 감응형 태양전지의 에너지 전환 효율을 향상시키고자 $TiO_2$에 $WO_3$을 첨가하여 광전극을 제조하고 그 전기화학적 특성 평가를 하였다. 또한 $WO_3$가 첨가된 $TiO_2$를 회쇄함으로써 회쇄 효과가 전지효율에 미치는 영향을 고찰하였다. I-V 곡선을 통하여 측정된 염료 감응형 태양전지의 효율은 $WO_3$ 첨가 및 회쇄 효과에 의하여 2.8에서 6.0%로 크게 증가하였다. 이와 같은 결과는 $TiO_2$의 전도대에서 전달되는 전자가 염료 및 전해질과 재결합되기 전에 $TiO_2$의 전도대보다 낮은 $WO_3$의 전도대를 통해 전달되기 때문에 전체 전류의 양이 증가되어 효율이 증가한 것으로 여겨진다. 또한, 임피던스 결과로부터 $TiO_2$/염료/전해질 계면의 저항 값이 감소하는 것을 확인하였다.

• Current Applied Physics
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• 제18권12호
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• pp.1583-1591
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• 2018

We analysed perovskite $CH_3NH_3PbI_{3-x}Cl_x$ inverted planer structure solar cell with nickel oxide (NiO) and spiroMeOTAD as hole conductors. This structure is free from electron transport layer. The thickness is optimized for NiO and spiro-MeOTAD hole conducting materials and the devices do not exhibit any significant variation for both hole transport materials. The back metal contact work function is varied for NiO hole conductor and observed that Ni and Co metals may be suitable back contacts for efficient carrier dynamics. The solar photovoltaic response showed a linear decrease in efficiency with increasing temperature. The electron affinity and band gap of transparent conducting oxide and NiO layers are varied to understand their impact on conduction and valence band offsets. A range of suitable band gap and electron affinity values are found essential for efficient device performance.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1996년도 추계학술발표회 논문집
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• pp.34-44
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• 1996

N-machine produces more than input energy at above 3000 rpm. any space energy is absorbed when the N-machine is rotating at a very high velocity. Laws of electromagnetics verify that normal conduction is due to that electrons moves from one three-dimensional crystallizing ${\pi}-bonding$ orbital to next. The ${\pi}-far$ infrared rays are generated from the resonance and rotation of the electrons on the orbitals of three-dimensional crystallizing ${\pi}-bonding$ atoms. Material in universe is composed of ${\pi}-rays$, which have alternative outward electric field. If the alternative outward electric fields of the ${\pi}-rays$ are resonant each other they make attraction force, which is the gravity. The collection of space energy is due to a attraction force between the radially alternating electric field and the ${\pi}-far$ infrared rays in the space. Electrons flow by absorbed density difference of ${\pi}-far$ infrared rays along a conduction wire, which also verifies that normal electron conduction is due to a flow from one three-dimensional crystallizing ${\pi}-bonding$ orbital to next.

• 한국진공학회지
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• 제9권2호
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• pp.130-135
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• 2000

Photoluminescence(PL)와 photoreflectance(PR)를 이용하여 $Al_{0.25}/Ga_{0.75}/As/In_{0.15}/Ga_{0.85}$/AS/GaAS 슈우도형 고 전자 이동도 트랜지스터 구조에 대한 특성을 조사하였다. 온도 10K의 PL측정에서 InGaAs 양자우물에 의한 e2-hl 및 e2-hl 전이 피크가 각각 1.322 및 1.397 eV에서 관측되었다. 온도 의존성으로부터 첫번째 가전자 띠와 두번째 가전자 띠의 에너지 차이는 약 23'meV로 나타났다. 또한 300 K에서의 PR 측정으로 e2-h2및 e2-hl 전이에 의한 피크를 관측하였고, 두번째 전도 띠의 에너지 준위에 의한 피크가 띠 채움으로 인해 첫번째 전도 띠의 에너지 준위에 의한 피크보다 상대적으로 우세하였다. 반면에 PL 측정에서는 전자 가리개 효과 때문에 첫번째 전도 띠에 의한 피크가 우세하였다.

• 한국수소및신에너지학회논문집
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• 제22권5호
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• pp.656-662
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• 2011

The purpose of this study was to correlate between photoelectrochemcial hydrogen production rate and electron transfer with various types of metal doped $TiO_2$ nanotubes as photoanodes. In order to fabricate light sensitized photoanode, CdS, $WO_3$, and Pt were doped by electrodeposition method. As the results of experiments, the electron transfer was favorable from higher position to lower position of conduction band (CB). In consequence, the higher hydrogen production rate was as follows, CdS/$TiO_2$ (100 $umol/hr-cm^2$) > $WO_3/TiO_2$ (20 $umol/hr-cm^2$) > Pt/$TiO_2$ (10 $umol/hr-cm^2$). The surface characterizations exhibited that crystal structure, morphological and electrical properties of various metal depoed $TiO_2$ nanotubes by the results of SEM, TEM, XPS, and photocurrent measurements.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.155-158
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• 1998

This paper is calculated at electron swarm simulation by Back Prolongation of Boltzmann equation for range of E/N values from 0.1~200[Td], pressure P= 1.0[Torr], temperature T=300[ 。K], the electron swarm parameter(drift velocity, longitudinal . transverse diffusion coefficients, characteristic energy, etc) in He gas is used by electron collision cross section, particularly explicate the simulation technique, and consider electrical conduction characteristic of He gas.

• E2M - 전기 전자와 첨단 소재
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• 제10권5호
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• pp.453-460
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• 1997

In order to investigate the electrical conduction properties of polyethylene thin film for power cable with manufacturing methods, the thickness of specimen was the 30, 100[${\mu}{\textrm}{m}$] of LDPE and 200[${\mu}{\textrm}{m}$] of XLPE were manufactured. The experimental condition for conduction properties was measured until the breakdown occurs at temperature ranges from 30 to 110[$^{\circ}C$] and the electric field from 1$\times$10$^3$to 5$\times$10$^{6}$ [V/cm]. As for increase of temperature, the current density of LDPE was increased with constant ratio in low field, but changes with exponential function in high electric field. The tunnel current of pre-breakdown region is shifted toward low field as much as thermal excitation energy. At low electric field, the XLPE showed dominant electrical conduction properties by thermal excitation, and transformation of the electron was resisted by the crystal at high electric field.

• 한국세라믹학회지
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• 제20권2호
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• pp.161-165
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• 1983

We studied the dependence of electrical conduction mechanism of Cupric Oxide on temperature and measured the specific resistivity of sintered specimen from $600^{\circ}C$ to 90$0^{\circ}C$ . We considered the relations between electrical conducti-vityand temperature with reheating the sintered specimen. X-Ray diffraction patterns showed that lattice parameters of cupric oxide increased above 20$0^{\circ}C$. Cupric oxide had nostoichiometric compositions$(CuO_{1+x})$ owing to the excess oxygen and showed hole conduction with energy gap of 0.15eV below $650^{\circ}C$$\pm$1$0^{\circ}C$ Above $650^{\circ}C$$\pm$1$0^{\circ}C$ cupic oxide had the stoichiometric composition and showed electron-hole conduction owing to the intrinsic ionization with energy gap of 1.04V.