• 한국전기전자재료학회논문지
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• 제17권4호
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• pp.361-366
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• 2004

The interface stability of Ta-Mo alloy film on SiO$_2$ was investigated. Ta-Mo alloy films were formed by co-sputtering method, and the alloy composition was varied by controlling Ta and Mo sputtering power, When the atomic composition of Ta was about 91％, the measured work function was 4.24 eV that is suitable for NMOS gate. To identify interface stability between Ta-Mo alloy film and SiO$_2$, C-V and XRD measurements were performed on the samples annealed with rapid thermal processor between $600^{\circ}C$ and 90$0^{\circ}C$. Even after 90$0^{\circ}C$ rapid thermal annealing, excellent interface stability and electrical properties were observed. Also, thermodynamic analysis was studied to compare with experimental results.

• 대한기계학회논문집
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• 제15권1호
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• pp.201-208
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• 1991

본 연구에서는 균일 열유동이 접합면에 수직으로 흐르고 접합 경계면 균열의 열경계조건이 단열되어 있는 경우에 균질 및 접합재료 모두에 적용될 수 있는 열응세 기계수를 복소해석방법을 이용하여 구하고자 한다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.526-530
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• 2004

We report the space charge and the surface potential of the interface between metal and CuPc according to isotropic property and different metal by measuring the microwave reflection coefficients $S_{11}$ of copper(II)-phthalocyanine(CuPc) thin films by using a near-field microwave microscope(NSMM) in order to understand. CuPc thin films were prepared on gold and aluminium substrates using a thermal evaporation method. Two kinds of CuPc thin films were prepared. One was deposited on preheated substrate at $150^{\circ}C$ and the other was annealed after deposition by using thermal evaporation methods. The microwave reflection coefficients $S_{11}$ of CuPc thin films were changed by the dependence on the heat treatment conditions. By comparing reflection coefficient $S_{11}$ we measured electrical conductivity of CuPc thin films and studied this results with respect to the surface potential and space charge of the interface between metal and CuPc thin films.

• 설비공학논문집
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• 제7권4호
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• pp.556-565
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• 1995

The physical model of interest is based upon the concentric cylinder, where the outside cylinder is filled with optically thick and high temperature phase change material(PCM). The fluid is flowing through the inside cylinder to transfer the appropriate energy. The fluid is flowing through the inside cylinder to transfer the appropriate energy. The governing equations for the phase change material including internal thermal radiation and for the turbulent transfer fluid have been employed and numerically solved. The optically thick phase change justifies the P-l spherical harmonics approximation, which is believed to be appropriate choice particularly for the much coupled problem like in this study. The solid/liquid interface, temperature distribution within the PCM and the heat flux from the PCM to the transfer fluid have been obtained and compared with those of laminar transfer fluid. The numerical results show that the turbulent transfer fluid accelerates the solid/liquid interface and results in the increase of heat transfer rate from the PCM. The internal thermal radiation within the PCM, however, does not always playa role to increase the heat transfer rate throughout the inside cylinder. It is believed that the combined heat flux has been picked up more in the inflowing area than in the pure conductive phase change material.

• 한국재료학회지
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• 제27권4호
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• pp.221-228
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• 2017

Various morphologies of copper oxide (CuO) have been considered to be of both fundamental and practical importance in the field of electronic materials. In this study, using Cu ($0.1{\mu}m$ and $7{\mu}m$) particles, flake-type CuO particles were grown via a wet oxidation method for 5min and 60min at $75^{\circ}C$. Using the prepared CuO, AlN, and silicone base as reagents, thermal interface material (TIM) compounds were synthesized using a high speed paste mixer. The properties of the thermal compounds prepared using the CuO particles were observed by thermal conductivity and breakdown voltage measurement. Most importantly, the volume of thermal compounds created using CuO particles grown from $0.1{\mu}m$ Cu particles increased by 192.5 % and 125 % depending on the growth time. The composition of CuO was confirmed by X-ray diffraction (XRD) analysis; cross sections of the grown CuO particles were observed using focused ion beam (FIB), field emission scanning electron microscopy (FE-SEM), and energy dispersive analysis by X-ray (EDAX). In addition, the thermal compound dispersion of the Cu and Al elements were observed by X-ray elemental mapping.

• 공업화학
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• 제21권2호
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• pp.115-128
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• 2010

마이크로 프로세서 및 항공 우주산업의 기술 발전에 따른 냉각 조건이 까다로워짐에 따라 각종 산업에서 열 전도 향상을 통한 기기 내에서 외부로의 열 배출은 최근 각광을 받고 있다. 특히 열 전도성 고분자 복합재료의 경우 매우 다양한 물질을 사용하여 그 요구조건에 맞는 부품의 생산이 가능하고 가공 편의성으로 인한 마이크로 부품에서부터 큰 부속품까지 그 사용 범위가 넓다. 방열 소재로 사용되는 고분자 복합재료의 열전도도 예측 모델 식을 알아보고 방열 소재에 대해 알아보며 상업적으로 많이 사용되고 있는 충전제에 대해 다룬다. 또한 최근의 고분자 복합재료 방열소재의 동향에 대해 알아본다.

• 한국세라믹학회지
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• 제43권8호
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• pp.479-485
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• 2006

The residual stress changes on thermo-mechanical loading in the interface region of the Thermal Barrier Coating (TBC)/Thermally Grown Oxide (TGO)/Bond Coat (BC) were calculated on the TBC-coated superalloys using a Finite Element Method (FEM). It was found that the residual stress of the interface boundary was dependent upon mainly the oxide formation and the swelling rate of the oxide by creep relaxation. During an oxide swelling, the relaxation of residual stress which is due to creep deformation increased the TBC's life. In the case of the fine grain size of TGO scale, the TBC stresses piled up by oxide swelling could be relaxed by diffusional creep effect of TGO.

• 접착 및 계면
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• 제7권4호
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• pp.45-52
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• 2006

Five low molar ratio urea-formaldehyde (LUF) resins were synthesized in this study. The effects of molar ratio, free formaldehyde content, and catalysts on the curing characteristics of LUF resins were studied by measuring its free formaldehyde content, pH value change after catalysts added, curing rate, and pot life, observing its cured appearance, and analyzing its thermal behavior. The results indicate that: 1) The LUF resin with lower molar ratio than 1.0 can still cure; 2) Free formaldehyde content is not the main factor in affecting curing rate of LUF resin; 3) Compared with ammonium chloride as a traditional catalyst, persulfate salts markedly accelerate the curing rate of LUF resin, and result in the different appearance; 4) the addition of sodium chloride to catalysts can accelerate the curing rate of LUF resin, but the effect is moderate.

• Corrosion Science and Technology
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• 제14권4호
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• pp.161-165
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• 2015

This paper presents an analysis of thermal stress induced along the interface between a polymeric coating layer and a steel substrate as a result of uniform temperature change. The epoxy layer is assumed to be a linear viscoelastic material and to be theromorheologically simple. The viscoelastic boundary element method is employed to investigate the behavior of interface stresses. The numerical results exhibit relaxation of interface stresses and large stress gradients, which are observed in the vicinity of the free surface. Since the exceedingly large stresses cannot be borne by the polymeric coating layer, local cracking or delamination can occur at the interface corner.

• 한국전기전자재료학회논문지
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• 제31권4호
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• pp.198-202
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• 2018

In this work, we have investigated the effect of a 30-min thermal anneal at $550^{\circ}C$ on the electrical characteristics of neutron-irradiated 4H-SiC MOSFETs. Thermal annealing can recover the on/off characteristics of neutron-irradiated 4H-SiC MOSFETs. After thermal annealing, the interface-trap density decreased and the effective mobility increased in terms of the on-characteristics. This finding could be due to the improvement of the interfacial state from thermal annealing and the reduction in Coulomb scattering due to the reduction in interface traps. Additionally, in terms of the off-characteristics, the thermal annealing resulted in the recovery of the breakdown voltage and leakage current. After the thermal annealing, the number of positive trapped charges at the MOSFET interface was decreased.