• 전자공학회논문지A
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• 제31A권3호
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• pp.46-52
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• 1994

We investigated theoretically the current-voltage characteristics of resonant tunneling diodes with a single quantum well structure. using a self-consistent method. This method is a numerical analysis which is able to include the effects of the undoped spacer layer and the band bending by charge accumulation and depletion on the contact layers which have not been considered in the flat-band model reported by Esaki. so that it is better suited to explain experimental results. The structure used is an $AL_{0.5}Ga_{0.5}AS/GaAs/Al_{0.5}Ga_{0.5}AS$ single quantum well. In this work. we estimate the theoretical current-voltage characteristics of the same structure, and then, the dependence of the current-voltage curves on the thickness of undoped spacer layers sandwiched between the barrier and highly n-doped GaAs contact layer.

• 대한전자공학회논문지
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• 제13권2호
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• pp.1-4
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• 1976

LiN103의 X캇트판의 공진주파수의 온도특성을 구하는 이론적 방법을 제안하고 계산결과 공진주파수의 온도계수가 -78.43x10-0/℃임을 알았다. In this paper, temperature dependence of the resonant frequency of thickness shear mode in X cut plate of Li.NbO3 is theoretically analyzed. An a result of this analysis, theoretical value -78.43×10-6/℃ of the temperature coefficient of resonant frequency is obtained.

• 한국결정성장학회지
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• 제8권3호
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• pp.411-418
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• 1998

LPCVD 방법으로 실리콘 산화막 두께 10nm에서 80nm인 MOS를 제작하였다. 그리고 스트레스 전계 산화막 전류의 두께 의존성을 조사하였다. 산화막 전류는 스트레스 전류와 전이전류로 구성되어 있음을 보여 주었다. 스트레스 전류는 스트레스 유기 누설전류와 직류전류로 이루어졌으며 산화막을 통하는 트립 어시스트 터널링으로 행해진다. 전이전류는 계면에서 트랩의 터널링 충전과 방전에 의해 이루어진다. 스트레스 전류는 산화막 전류의 두계 한계를 평가하는데 이용되고 전이전류는 기억소자에서 데이터 유지에 사용된다.

• 대한기계학회논문집B
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• 제21권3호
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• pp.445-456
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• 1997

Continuous casting process is numerically analyzed using the continuum model in a non-orthogonal coordinate system. Flow damping in the mush is modeled by combining the viscosity dependence on liquid fraction in dilute mush and the permeability dependence on liquid fraction in concentrated mush. The effect of turbulence is indirectly considered by effective diffusivity determined elsewhere by experiment. The main objective is to investigate the effects of casting parameters such as casting speed and tundish superheat on the distribution of surface temperature, shell thickness, metallurgical length and centerline segregation. Some of the computed results are compared with available experiments, and reasonable agreements are obtained.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.80-82
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• 2009

The dependence of the efficiency characteristics of hydrogenated amorphous silicon single junction solar cells on the various intrinsic layer thickness has been investigate in the glass/$SnO_2$:F/p,i,n a-Si:H/Al type of amorphous silicon solar cells by cluster PECVD system. The open circuit voltage, short circuit current, fill factor and conversion efficiency have been measured under AM 1.5 condition. The result of the cell performance was improved about 8.2% due to an increase in the short circuit current.

• 대한전기학회논문지
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• 제44권7호
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• pp.901-907
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• 1995

The switching characteristics of As$_{10}$ Ge$_{15}$ Te$_{75}$ thin film were investigated under d.c. bias. And the frequency dependence of the conductivity was analysed with regard to the temperature dependence, in order to find the physical properties of the As$_{10}$ Ge$_{15}$ Te$_{75}$ thin film ; a characteristic relaxation time (.tau.$_{0}$ ), the spatial density of defect states (N), and the localized wavefunction (.alpha.$^{-1}$ ). It was formed that the threshold voltage depends on thickness, electrode distance, annealing time and temperature, respectively. The threshold voltage is increased as the thickness and the electrode distance is increased, while the threshold voltage is decreased in proportion to the increased annealing time and temperature.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.356.2-356.2
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• 2014

Spin Transfer Torque (STT) is of great interest in data writing scheme for the Magneto-resistive Random Access Memory (MRAM) using Magnetic Tunnel Junction (MTJ). Scalability for high density memory requires ferromagnetic electrodes having the perpendicular magnetic easy axis. We investigated CoZr as the ferromagnetic electrode. It is observed that interfacial magnetic anisotropy is preferred perpendicular to the plane with thickness dependence on the interfaces with Pt layer. The anisotropy energy (Ku) with thickness dependence shows a change of magnetic-easy-axis direction from perpendicular to in-plane around 1.2 nm of CoZr. The interfacial anisotropy (Ki) as the directly related parameters to switching and thermal stability, are estimated as $1.64erg/cm^2$ from CoZr/Pt multilayered system.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.239-242
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• 1999

In this study, we evaluates the dependence of thickness and temperature in the breakdown strength of MDPE and effect of semiconductor. As the result, breakdown strength trend to decrease according to the increase of thickness and temperature but there is no dependence of temperature in the 70${\mu}{\textrm}{m}$ MDPE film. We obtained the result that the breakdown strength was a little lower in the structure of Semil/MDPE than Semi/MDPE/Semi, but breakdown strength of MDPE was greater both of all. Therefore we are investigating the effect of semiconductor in the breakdown strength.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.1171-1173
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• 1993

Dielectric breakdown strength of LDPE films was investigated using metal electrodes and semiconductive electrodes respectively. In both of two cases, the results show that there are characteristics of dependence on thickness and dependence on temperature. However, there are some differences in both cases.

• Journal of Magnetics
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• 제11권2호
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• pp.70-73
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• 2006

The magnetization angle and thickness dependence of magnetic anisotropy in the exchange-biased [Pd/Co]${\times}$5/FeMn multilayers with an out-of-plane anisotropy were investigated to determine the origin of perpendicular exchange biasing. As the Co thickness increased to 1.5 nm in the [Pd(0.8 nm)/Co(t)]${\times}$5/FeMn(120 nm) films, the hysteresis loops were converted from square loops at a thin Co (<0.4 nm) to complicated round ones at a thick Co. The irregularly asymmetric step (IAS) at the left top of the loop appeared in the loop of the 0.6-nm Co film due to an inhomogeneity in the exchange anisotropy. As the Pd thickness increased to 1.6 nm, the step disappeared, and the perpendicular magnetic anisotropy was maximized in the Co thickness between 0.6 and 0.9 nm. The conversion of the magnetization loop along the magnetization angle coincided with the equation $H_{(eff)}=H_o\;cos{\theta}$. The IAS of the 0.8-nm Pd film disappeared after thermal annealing up to $200^{\circ}C$ under an external magnetic field.