• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.257-260
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• 2007

Hydrogenated amorphous silicon thin film transistors were fabricated on a flexible metal substrate. A negative voltage at a floated gate can be induced by a negative substrate bias through a capacitor between the substrate and gate electrode. This can recover the shifted-threshold voltage to an original value.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1632-1635
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• 2007

We developed a novel growth method of CNTs on metal substrate for device applications, deposited by a triode direct current plasma enhanced chemical vapor deposition (dc-PECVD). With resist-assisted patterning (RAP) method, we had grown CNTs on metal substrate, which were strongly bonded with metal substrate.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 춘계학술발표강연 및 논문개요집
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• pp.44-44
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• 2003

Growth mechanism of carbon nanotubes(CNTs) synthesized by chemical vapor deposition is abided by two growth modes. These growth modes are classified by the position of activated catalytic metal particle in the CNTs. Growth mode can be also affected by interaction between substrate and catalytic metal and induced energy such as thermal and plasma. We studied the reaction of catalytic metal to the substrate and growth mode of CNTs. Various substrates such as Si(100), graphite plate, coming glass, sapphire and AAO membrane are used to study the relation between catalytic metal and substrate in the synthesis of CNTs. For catalytic metal, thin film was deposited on various substrate via sputtering technique with a thickness of ∼20nm and magnetic fluids with none-sized particles were dispersed on AAO membrane. After laying process on AAO membrane, it was dried at 80$^{\circ}C$ for 8 hour. Synthesizing of CNTs was carried out at 900$^{\circ}C$ in NH3/C2H2 mixture gases flow for 10minutes.

• 한국재료학회지
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• 제24권7호
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• pp.344-350
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• 2014

Metal films (i.e., Ti, Al and SUH310S) were prepared in a magnetron sputtering apparatus, and their cross-sectional structures were investigated using scanning electron microscopy. The apparatus used consisted of a cylindrical metal target which was electrically grounded, and two anode rings attached to the top and to the bottom of the target. A wire was placed along the center-line of the cylindrical target to provide a substrate. When the electrical potential of the substrate was varied, the metal-film formation rate depended on both the discharge voltage and the electrical potential of the substrate. As we made the magnetic field stronger, the plasma which appeared near the target collected on the plasma wall surface and thereby decreased the bias current. The bias current on the conducting wire was different from that for cation collection. The bias current decreased because the collection of cations decreased when we increased the magnetic-coil current. When the substrate was electrically isolated, the films deposited showed a slightly coarse columnar structure with thin voids between adjacent columns. In contrast, in the case of the grounded substrate, the deposited film did not show any clear columns but instead, showed a densely-packed granular structure. No peeling region was observed between the film and substrate, indicating good adhesion.

• Journal of Welding and Joining
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• 제18권4호
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• pp.55-63
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• 2000

This paper presents a study of the solder bumping process. The theoretical model, based on the variational principle instead of solving the Navier-Stokes equation with moving boundaries, was developed to considered the energy dissipation in semi-solid phase and the approximate solidification time of the molten metal droplet. The simulation results revealed that the developed model could reasonably describe the collision behavior of molten metal with solid surface. Simulations were made with variation of initial droplet temperature, substrate metal and initial substrate temerature.

• Toxicological Research
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• 제23권1호
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• pp.1-9
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• 2007

Transporters are membrane proteins that mediate the transfer of substrate across the cellular membrane. In this overview, the characteristics and the toxicological relevance were discussed for various types of transporters. For drug transporters, the overview focused on ATP-binding cassette transporters and solute carrier family 21A/22A member transporters. Except for OCTN transporters and OATP transporters, drug transporters tend to have broad substrate specificity, suggesting drug-drug interaction at the level of transport processes (e.g., interaction between methotrexate and non-steroidal anti-inflammatory agents) is likely. For metal transporters, transporters for zinc, copper and multiple metals were discussed in this overview. These metal transporters have comparatively narrow substrate specificity, except for multiple metal transporters, suggesting that inter-substrate interaction at the level of transport is less likely. In contrast, the expressions of the transporters are often regulated by their substrates, suggesting cellular adaptation mechanism exists for these transporters. The drug-drug interactions in drug transporters and the cellular adaptation mechanisms for metal transporters are likely to lead to alterations in pharmacokinetics and cellular metal homeostasis, which may be linked to the development of toxicity. Therefore, the transporter-mediated alterations may have toxicological relevance.

• Journal of electromagnetic engineering and science
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• 제7권1호
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• pp.47-52
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• 2007

We investigated the effects of substrate, metal-line, and surface material on the performance of radio frequency identification(RFID) tag antenna using a tag antenna with a meander line radiator and T-matching network. The results showed that readability of the tag antenna with a thin high-loss substrate could be increased so that it was similar to that of a low-loss substrate if the substrate was very thin. The readability of the tag antenna decreased significantly when the metal line was thinner than the skin depth. The readability of the tag also decreased drastically when the tag was attached to high-permittivity high-loss target objects.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1304-1309
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• 2004

Synthesis of carbon nanotubes and nanofibers on a catalytic metal substrate, using an ethylene fueled inverse diffusion flame, was investigated. Multi-walled carbon nanotubes, with diameters of 20 - 60nm, were formed on the substrate coated with nickel-nitrate in the region of 5 - 6mm from the flame center along the radial direction. The gas temperature for this region was ranging from about 1400 to 900K. Nickel particles originated from the coated nickel-nitrate on the substrate were the major catalyst for the formation of the nanomaterials. HR-TEM and Raman spectrum revealed that synthesized carbon nanotubes had multi-walled structures with some defective graphite layers at walls.

• 마이크로전자및패키징학회지
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• 제30권1호
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• pp.63-70
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• 2023

오늘날 심각한 환경 오염과 에너지의 중요성으로 전력 반도체의 중요도가 지속적으로 높아지고 있다. 특히 wide band gap(WBG)소자 중 하나인 SiC-MOSFET은 우수한 고전압 특성을 가지고 있어 그 중요도가 매우 높다. 하지만 SiC-MOSFET의 전기적 특성이 열에 민감하기 때문에 패키지를 통한 열 관리가 필요하다. 본 논문에서는 기존 전력 반도체에서 사용하는 direct bonded copper(DBC) 기판 방식이 아닌 insulated metal substrate(IMS) 방식을 제안한다. IMS는 DBC에 비해 공정이 쉬우며 coefficient of thermal expansion (CTE)가 높아서 비용과 신뢰성 측면에서 우수하다. IMS의 절연층인 dielectric film의 열전도도가 낮은 문제가 있지만 매우 얇은 두께로 공정이 가능하기 때문에 낮은 열 전도도를 충분히 극복할 수 있다. 이를 확인하기 위해서 이번 연구에서는 electric-thermal co-simulation을 수행하였으며 검증을 위해 DBC 기판과 IMS를 제작하여 실험하였다.

• 한국진공학회지
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• 제12권S1호
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• pp.74-78
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• 2003

In this paper, we studied, by numerical calculation, a system, which was composed of metal-film and metal-substrate irradiated by IPIB with beam ion energy 250 keV, current density 10 to 250 A/$\textrm{cm}^2$. While the IPIB irradiation was going on, an induced effect named mixing occurred. In this case, metal-film and part of metal-substrate melted and mixed. The mixing state was kept as it was in melting phase due to the fast cooling rate. Our works were simulating the heating and cooling process via our STEIPIB program and tried to find proper parameters for a specific film-substrate system, 500 nmtitanium film coated on aluminum, to get best mixing results. The parameters calculated for such Ti-Al system were compared with the experimental results and were in good accordance to the experimental results.