• 한국산업보건학회지
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• 제26권2호
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• pp.119-138
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• 2016

Objectives: The purpose of this study is to review size, shape, and crystal structure-dependent toxicity of major metal oxide particles such as silicon dioxide, tungsten trioxide, aluminum oxide, and titanium dioxide as byproducts generated in semiconductor fabrication facility. Methods: To review the toxicity of major metal oxide particles, we used various reported research and review papers. The papers were searched by using websites such as Google Scholar and PubMed. Keyword search terms included '$SiO_2$(or $WO_3$ or $Al_2O_3$ or $TiO_2$) toxicity', 'health effects $SiO_2$(or $WO_3$ or $Al_2O_3$ or $TiO_2$). Additional papers were identified in references cited in the searched papers. Results: In various cell lines and organs of human and animals, cytotoxicity, genotoxicity, hepatoxicity, fetotoxicity, neurotoxicity, and histopathological changes were induced by silicon dioxide, tungsten trioxide, aluminium oxide, and titanium dioxide particles. Differences in toxicity were dependent on the cell lines, organs, doses, as well as the chemical composition, size, surface area, shape, and crystal structure of the particles. However, the doses used in the reported papers were higher than the possible exposure level in general work environment. Oxidative stress induced by the metal oxide particles plays a significant role in the expression of toxicity. Conclusions: The results cannot guarantee human toxicity of the metal oxide particles, because there is still a lack of available information about health effects on humans. In addition, toxicological studies under the exposure conditions in the actual work environment are needed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.364-364
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• 2010

In the electricity control field, a relay is the most widely used electrical switch. But it has problems about a material transfer phenomenon, contact bounce, and the mechanical life. These Problems cause the serious problem in a facility. So, we tried to solve these problems by applying MOSFET electronic switch and could find good improvement compared to conventional electrical switch.

• 한국화재소방학회논문지
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• 제14권4호
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• pp.23-28
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• 2000

반도체 공장의 제연설계를 위한 성능기준 설계를 분석하였다. 사례분석을 통하여 제연 설계 시스템의 성능평가 기준을 설정하고 최적의 배연 방법을 분석하기 위한 FDS 화재모델링을 수행하였다. 제연 설계 지침이나 관련 법규 또는 표준화된 기준이 부족한 한국과 미국의 현실에서 본 연구의 성능기준 설계 방법은 반도체공장의 제연 설계를 위한 현실적인 적용과 활용이 기대된다.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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• pp.110-115
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• 2004

Examine merits and demerits and obstacle factor that exist to all direction of digital infratechnology that is supplied on industry whole according to development special quality of computer by development of computer and Information Technology and electricity electron information communication facility that basic impulse insulation level does not exist examined scorched earth or an interference problem factor and countermeasure of semiconductor degauss of factor and electricity electron information transmission system that is numbed or causes system down.

• 한국BIM학회 논문집
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• 제6권4호
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• pp.18-26
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• 2016

Recently, for the purpose of maintenance of facilities and energy, there have been growing cases of the 3D image scan-based reverse design technology mostly in the manufacturing field. In the MEP field, because of differences between design and physical model, the reverse technology has been utilized in factory facilities such as a semiconductor factory. Because 3D point clouds from scanning include accurate 3D object information, the efficiency of management works related to the complex MEP facilities can be enhanced. In this study, the reverse technology was surveyed, and the MEP facility management based on 3D image scanning was analyzed. Based on the results, a method of 3D image scan-based MEP facility management was proposed.

• 방사선산업학회지
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• 제6권1호
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• pp.67-73
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• 2012

The development of radiation detection systems mainly consist of two parts-radiation detector fabrication including material development, and its appropriate electronics development. For the core-technology incubation of a radiation detection system, radiation fabrication and an evaluation facility are scheduled to be founded at the RFT (Radiation Fusion Technology) Center at KAERI (Korea Atomic Energy Research Institute) by 2015. This facility is utilized for the development and incubation of bottleneck-technologies to accelerate the industrialization of a radiation detection system in the industrial, medical, and radiation security fields. This facility is also utilized for researchers to develop next-generation radiation detection instruments. In this paper, the establishment of core-technology development is introduced and its technological mission is addressed.

• 방사선산업학회지
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• 제10권1호
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• pp.37-41
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• 2016

The recent prevalence of PET examinations in Korea has led to an increase in the number of cyclotrons. The medical isotope $^{18}F$ produced in most cyclotron facilities currently operating in Korea is emitted into the environment during the production of [$^{18}F$]FDG, a cancerdiagnosis reagent. The amount of [$^{18}F$]FDG synthesized determines the radioactive concentration of $^{18}F$ in the exhaust. At some facilities, this amount temporarily exceeds the emission limit. In this study, we evaluated the $^{18}F$ radioactivity concentration in the exhaust from the cyclotron facility at Chosun University. The $^{18}F$ radioactivity concentration was measured using an air sampler and a HPGe semiconductor detector. The measurements showed that the radioactive concentration of $^{18}F$ in the exhaust at the cyclotron facility at Chosun University was the highest during [$^{18}F$]FDG synthesis but remained under the legal limit of $2,000Bq\;m^{-3}$.

• 산업경영시스템학회지
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• 제39권1호
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• pp.73-80
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• 2016

This study focuses on the formation of input release lots in a semiconductor wafer fabrication facility. After the order-lot pegging process assigns lots in the fab to orders and calculates the required quantity of wafers for each product type to meet customers' orders, the decisions on the formation of input release lots should be made to minimize the production costs of the release lots. Since the number of lots being processed in the wafer fab directly is related to the productivity of the wafer fab, the input lot formation is crucial process to reduce the production costs as well as to improve the efficiency of the wafer fab. Here, the input lot formation occurs before every shift begins in the semiconductor wafer fab. When input quantities (of wafers) for product types are given from results of the order-lot pegging process, lots to be released into the wafer fab should be formed satisfying the lot size requirements. Here, the production cost of a homogeneous lot of the same type of product is less than that of a heterogeneous lot that will be split into the number of lots according to their product types after passing the branch point during the wafer fabrication process. Also, more production cost occurs if a lot becomes more heterogeneous. We developed a multi-dimensional dynamic programming algorithm for the input lot formation problem and showed how to apply the algorithm to solve the problem optimally with an example problem instance. It is necessary to reduce the number of states at each stage in the DP algorithm for practical use. Also, we can apply the proposed DP algorithm together with lot release rules such as CONWIP and UNIFORM.

• 경영과학
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• 제32권4호
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• pp.69-80
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• 2015

The semiconductor industry is one of those in which the most intricate processes are involved and there are many critical factors that are controlled with precision in those processes. Naturally production scheduling in the semiconductor industry is also very complex and studied by the industry and academia for many years; however, still there are many issues left unclear in the problem. This paper proposes an multi-objective optimization-based scheduling method for semiconductor fabrication(fab). Two main objectives are throughput maximization and meeting target production quantities. The first objective aims to reduce production cost, especially the fixed cost incurred by a large investment constructing a new fab facility. The other is meeting customer orders on time and also helps a fab maintain stable throughput through controlled WIP balancing in the long run. The paper shows a trade-off structure between the two objectives through experimental studies, which provides industrial practitioners with useful references.

• 한국입자에어로졸학회지
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• 제14권2호
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• pp.41-47
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• 2018

Numerical analysis was conducted to characterize particle deposition onto a heated horizontal semiconductor wafer in vacuum environment. In order to calculate the properties of gas surrounding the wafer, the gas was assumed to obey the ideal gas law. Particle transport mechanisms considered in the present study were convection, Brownian diffusion, gravitational settling and thermophoresis. Averaged particle deposition velocities on the upper surface of the wafer were calculated with respect to particle size, based on the numerical results from the particle concentration equation in the Eulerian frame of reference. The deposition velocities were obtained for system pressures of 1000 Pa~1 atm, wafer heating of 0~5 K and particle sizes of $2{\sim}10^4nm$. The present numerical results showed good agreement with the available experimental ones.