• Journal of the Korean Vacuum Society
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• v.16 no.1
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• pp.40-45
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• 2007

ZnCdSe alloy semiconductor was widely used for the optoelectronic device. And CdSe is the end-point in this material. In this work, we measured the dielectric function spectrum of cubic CdSe with Vacuum Ultra Violet spectroscopic ellipsometry and analysed this data with parametric model. As a result, we observed some of transition energy point over 6 eV and obtained the database for dielectric function spectrum, which could be used for temperature or alloy composition dependence study on optical property of CdSe.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.12
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• pp.1165-1174
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• 2016

The energy band gaps and the bowing parameters of zincblende InAs1-xN are determined by using an empirical pseudopotential method(EPM) within the improved virtual crystal approximation(VCA), which includes the disorder effect. The direct-band-gap bowing parameter calculated by using the EPM is 4.1eV for InAs1-xNx ($0{\leq}x{\leq}0.05$). The dependences of the band gaps of N-dilute InAs1-xNx on the temperature and composition are calculated by modifying the band anti-crossing(BAC) model. The calculation results are consistent with experimental values, and the coupling parameter CMN of InAs1-xNx is found to be equal to 1.8 by fitting the EPM data.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1994.10a
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• pp.58-61
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• 1994

본 연구에서는 내부 외부 진동원(8-30Hz)에 따른 격자보 구조의 동적 응답을 효과적으로 제어하기 위해 격자보 구조의 동적 거동에 지배적인 영향을 미치는 철근비, 질량, 탄성계수 등 여러 인자들의 비교, 분석을 통해 동적 거동에 영향을 미치는 인자를 분석함으로써 격자보 구조의 설계시 인자의 변화에 따른 동적 거동 특성을 예측하여 이에 적절히 대응할 수 있도록 도모하였다. 이를 위해 국내에 건설된 반도체 공장의 격자보 구조 중에서 기본 해석 모델을 결정하고 이에 대해 실험적 모드 해석과 유한 요소 해석을 사용해서 기본 해석 모델의 모드 매개변수를 구하고, 기본 해석 모델에 사용되는 각 인자가 고유 진동수에 미치는 영향을 비교.분석하였다.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.5
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• pp.877-886
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• 2019

The energy band gaps and optical constants of zincblende $In_yGa_{1-y}As_{1-x}N_x$ on the variation of temperature and composition are determined by using band anticrossing method. The energy band gaps are decreasing continuously in $In_yGa_{1-y}As_{1-x}N_x$ ($0{\leq}x{\leq}0.05$, $0{\leq}y{\leq}1.0$, 300K) and the bowing parameter is calculated as 0.522eV. The calculation results of energy band gaps are consistent with those of other studies. A refractive index n and a high-frequency dielectric constant ${\varepsilon}$ are calculated by a proposed modeling equation using the results of energy band gaps.

• Journal of the Korea Society for Simulation
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• v.27 no.2
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• pp.125-137
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• 2018

Simulations have been used to evaluate the efficiency of logistics or manufacturing systems and predict the outcomes of the systems. New simulation models are needed to evaluate new alternative plants and layouts during the resource design process. Although it is easy to handle minor changes in parameters by modifying a simulation model, it takes considerable time and effort for simulation modelers to alter the layout, which involves changes in many simulation sub-models. Therefore, this study proposes a method to transfer information in AutoCAD layout to the simulation model automatically. This study also defines a standard document as an Excel Form, and suggests a method to transfer information on the basic layouts, processes, resources, and workers to a simulation model automatically. A simulation tool, called Tecnomatix Plant Simulation 9.0, was used for this study. The proposed approach in this study was applied to a semiconductor wafer factory for a case study.

• Journal of the Korean Society for Nondestructive Testing
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• v.19 no.5
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• pp.369-377
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• 1999

Recently, it is gradually raised necessity that thickness of thin film is measured accuracy and managed in industrial circles and medical world. Ultrasonic signal processing method is likely to become a very powerful method for NDE method of detection of microdefects and thickness measurement of thin film below the limit of ultrasonic distance resolution in the opaque materials, provides useful information that cannot be obtained by a conventional measuring system. In the present research. considering a thin film below the limit of ultrasonic distance resolution sandwiched between three substances as acoustical analysis model, demonstrated the usefulness of ultrasonic signal processing technique using information of ultrasonic frequency for NDE of measurements of thin film thickness. Accordingly, for the detection of delamination between the junction condition of boundary microdefect of thin film sandwiched between three substances the results from digital image processing.

• The Journal of Korean Institute for Practical Engineering Education
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• v.3 no.1
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• pp.15-24
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• 2011

Modeling and simulation for Green Energy depends largely on the type of system under investigation. The topics are very wide ranging from semiconductor physics (solar), electrical motor/generator (wind turbines), power electronics (grid connections) to typical control strategies. To correctly model these technologies requires a broad set of models and various simulation techniques. To further refine or detail the simulation the modeling has to be performed on a specific level, being system, circuit or component level. Combinations of several levels allows gradually improving the validity of the overall model against available parameters and model equations.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.402-402
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• 2012

최근 반도체 공정 중 fluorocarbon (CxHyFz) 가스와 함께 플라즈마 밀도가 큰 유도결합형 플라즈마을 사용한 식각장비가 많이 사용되고 있다. 특히 저 유전상수 값을 가지는 박막을 밀도가 큰 플라즈마와 함께 fluorocarbon 가스를 이용하여 식각을 하게 되면 매우 복잡한 현상이 생긴다. 따라서 식각률에 대한 모델을 세우고 적용하는 일이 매우 어렵다. 본 연구에서는 CF4가스를 Ar가스와 함께 혼합하고 기판 플라즈마와 유도결합형 플라즈마를 동시에 가진 식각장비를 사용하여, 저 유전상수 값을 갖는 박막을 식각하였다. 또한, 간단한 식각모델인 Langmuir adsorption model를 이용하여 식각률(Etch rate)에 대한 합리적인 이해를 얻기 위해, 기판과 유도결합형 플라즈마의 파워에 따른 식각률을 계산하고, 식각모델에서 사용되는 매개변수인 이온플럭스(Ion Flux)와 식각수율(Etch yield)을 연구하였다. 기판의 플라즈마 파워가 20에서 100 W 증가하면서 식각률이 269에서 478 nm/min로 증가하였으며, 식각수율이 0.4에서 0.59로 증가하는 것을 관찰하였다. 반면에 기판의 플라즈마 파워 증가에 따라 이온 플럭스는 3.8에서 $4.7mA/cm^2$로 변화가 크지 않았다. 또한, 유도결합형 플라즈마의 파워가 100에서 500 W 증가하면서, 식각률이 117에서 563 nm/min로 증가하였으며, 이온플럭스가 1.5에서 $6.8mA/cm^2$으로 변화하였다. 그러나, 식각수율은 0.46에서 0.48로 거의 변화하지 않았다. 그러므로 저 유전상수 값을 가지는 박막 식각의 경우, 기판의 플라즈마는 식각수율을 증가시키며 유도결합형 플라즈마는 이온 플럭스를 증가시켜 박막 식각에 기여하는 것으로 사료된다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.639-647
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• 2019

Recently, as the semiconductor integration technology due to miniaturization and high density of electronic equipment have developed, it is importantly recognized the application of thermal control system in order to release inner heat generated from chips, modules, In this study, we considered the heat transfer and pressure drop characteristics in a horizontal channel with four blocks using k-${\omega}$ SST turbulence model During CFD (Computational Fluid Dynamics) analysis, the parameters applied block width, block height, heat source and turbulence generator placement etc. As the boundary conditions of analysis, the channel inlet temperature and flow velocity were respectively 300 K and 3.84 m/s, the heat flux was $358W/m^2$. As a result, the heat transfer performance was decreased as the block width ratio (w/h) was increased, while it was increased as the block height ratio (h/w) was increased. In addition, as the arrangement of heat source size was increased to high heat flux from low heat flux, it was influenced by heat source size and the heat transfer coefficient showed a tendency to increase, When the turbulence generator was installed in the upper part of block No. 1 position the closely to the channel entrance, the heat transfer characteristics was greatly influenced on the whole of four heating blocks. and in oder to consider the pressure drop characteristics, we are able to select the most appropriate turbulence generator's position.