• 대한전자공학회논문지SD
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• 제44권4호
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• pp.32-42
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• 2007

[ $0.35{\mu}m$ ]twin-well non-epitaxial CMOS 공정에서의 substrate noise에 의한 아날로그 회로의 성능 저하를 예측하기 위하여 substrate 저항을 모델링하였다. Substrate 저항 모델 방정식은 P+ guard-ring isolation에 적용되어 측정값과 일치함을 확인하였다. Substrate 저항을 네 가지 형태로 구분하고 각각에 대하여 semi-empirical 모델 방정식을 확립하여, 측정값과 비교하여 rms 오차가 10% 미만이 되었다. 이 substrate 저항 모델을 guard-ring에 의한 isolation 구조에 적용하기 위하여 모델 방정식과 ADS(Advanced Design System) 회로 시뮬레이션에 의한 결과와 Network Analyzer의 측정 결과를 비교하였고, 비교적 잘 일치함을 확인하였다.

• 한국건축시공학회지
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• 제3권4호
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• pp.73-78
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• 2003

In this Study, we examined the influence of characteristics of rolling loads by casters on separation resistance of substrate concrete and synthetic resin floor coating. In the experiment, we first prepared floor samples having substrate concrete of various compressive strength, surface hardness and surface configurations, then put the coated samples to the test of separation resistance with Rolling Caster Loading Machine. Three loading conditions consisted of different kinds of casters, rolling conditions, and coating materials. Consequently, we clarified that the grade of separation resistance varied widely according to the characteristics of substrate concrete and rolling loads.

• 한국표면공학회지
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• 제30권1호
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• pp.33-43
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• 1997

The effects of process parameters substrate such as substrate current and substrate temperature on the corrosion resistance of ion plated TiN film were investigated. TiN fims were deposited on speed steel on which Ti or Ni hed been previously evaporated. Dense TiN films could be obtained under higher substrate current(1A) and substrate temperature($500^{\circ}C$), whereas TiN films deposited with lower substances current(0.5A) and substrate temperature($300^{\circ}C$) showed porous structure. The corrosion resistances of high speed steel was considerably increased when dense TiN films had been formed on it. The effect of Ti and Ni interlayer on the increase of the corrosion resistance was also significant with dense TiN films, while there was little effect of interlayer on the corrosion resistance when TiN films were porous. the effect of interlayer on the corrosion resistance was more outstanding with Ti then with Ni, because Ti reacts more easily with oxygen to form an oxide layer, and it also shows higher resistance against chlorine containing corrosion media.

• 한국표면공학회지
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• 제30권2호
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• pp.93-103
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• 1997

High temperature materials used in the elevated temperature and corrosive atmosphere must have the good oxidation resistance and preserve their own mechanical properties simultaneously. For the oxidation resistance, it is very important to form a protective oxide scale such as $Al_2O_3$ or $Cr_2O_3$ on the substrate. However, the additions of protective oxide forming elements such as Cr and Al in the alloy to enhance its oxidation resistance are limited due to the deleterious effects on their mechanical properties. PECVD(P1asma Enhanced Chemical Vapor Deposition) coating processes were employed to improve the oxidation resistance at high temperature. Cr and/or A1 were coated on the substrates of Ni and Inconel 600 at various temperatures of 400, 500, $600^{\circ}C$ and at different conditions of specimen surfaces. Then, coated specimens were exposed to isothermal and cyclic oxidation conditions in air at 1000 and $1100^{\circ}C$. In order to enhance the adhesion between the substrate and coated layer, heat treatments of the coated specimens were conducted in a vacuum. At isothermal oxidation experiments, Al-coated Ni specimen showed better oxidation resistance than pure Ni. At cyclic oxidation experiments at $1000^{\circ}C$. Cr and Al-coated specimen showed better oxidation resistance. Cr-coated Inconel 600 had also showed better oxidation resistance due to Cr in the substrate. By PECVD coating process, oxidation resistance could be improved, but it was not improved as expected due to the weakness of the adhesion between the substrate and the coated layer.

• 한국표면공학회지
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• 제49권3호
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• pp.252-259
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• 2016

In order to form an aluminum-doped zinc oxide (AZO) transparent electrode film on a polyethylene terephthalate (PET) substrate used for a flexible display substrate, the AZO transparent electrode was produced at low temperature without substrate heating. Even though the produced electrode showed characteristic optical transmittance of 90 % (at 550 nm) and sheet resistance within $100{\Omega}/sq$, cracks occurred 10 minutes after loading applied 2 mm radius of curvature, and the sheet resistance increased linearly. An insertion layer of ZrCu was formed between the AZO film and the PET substrate to suppress the generation of cracks on the AZO film. It was verified that the crack was not generated 30 minutes after the loading of 2 mm radius of curvature, and no increase in sheet resistance was recorded. There was also not cracks in the dynamic bending test of 4 mm radius, but surface resistance was slightly increased. As a result, the ZrCu insertion film improved the interfacial adhesion between the substrate and AZO film layer without increasing sheet resistance and decreasing transmittance.

• Corrosion Science and Technology
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• 제9권4호
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• pp.143-146
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• 2010

For the issue of flaking of the hot-dip galvanizing coating during drawing, the microcosmic characteristics of the coatings have been analyzed and experiments have been done to investigate the influence of coating thickness, Al content and steel substrate strength on its flaking-resistance. The results show that the fact of flaking is that the coating partially flaked off at the position far away from interface of steel substrate and coating, and not entirely flaked off from steel substrate because of poor adhesion. The flaking-resistance of coating decreases with the increasing of coating thickness and steel substrate strength, and increases with the increasing of Al content in coating at the same experimental conditions.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.393-394
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• 2008

This paper presents a new method to extract the substrate resistance by fitting current-dependent base resistance of parasitic BJT without a complex RF extraction method. The extracted substrate resistance values using the new method match well with those using the RF one, verifying the accuracy of the proposed DC technique.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.809-812
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• 2005

In this work, a new method for extracting substrate parameters of RF MOSFETs based on 3-port measurement is presented using device simulation. A T-type substrate resistance network is used. 3-port Y-parameter analyses were performed on the equivalent circuit of RF MOSFETs. All the components in the RF MOSFETs when the device is turned off were extracted directly from the 3-port device simulation data. The small-signal output admittance $Y_{22}$ can be well modeled up to 40 GHz. From the 3-port simulation and modeling results, it was verified that the proposed equivalent circuit and parameter extraction method was more accurate than the single substrate resistance model.

• International Journal of Internet, Broadcasting and Communication
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• 제7권2호
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• pp.161-167
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• 2015

The performance of high power LEDs highly depends on the junction temperature. Operating at high junction temperature causes elevation of the overall thermal resistance which causes degradation of light intensity and lifetime. Thus, appropriate thermal management is critical for LED packaging. The main goal of this research is to improve thermal resistance by optimizing and comparing nano-pore silicon-based thermal substrate to insulated metal substrate and direct bonded copper thermal substrate. The thermal resistance of the packages are evaluated using computation fluid dynamic approach for 1 W single chip LED module.

• 한국표면공학회지
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• 제37권3호
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• pp.158-163
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• 2004

ITO thin film was deposited on the glass by RF magnetron sputtering. Dependance of the process parameters such as thickness, target-to-substrate distance, substrate temperature and oxygen partial pressure on the transmittance and electrical resistance of ITO film were investigated. The deposition conditions for getting better optical and electrical ITO characteristics were the 1800-$2300\AA$ thickness, 65mm substrate-to-target distance, $350^{\circ}C$ substrate temperature and 8% oxygen partial pressure. At these conditions, the transmittance and sheet resistance of the ITO film were 83.3% and 77.86Ω/$\square$, respectively.