• 한국진공학회지
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• 제16권5호
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• pp.348-352
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• 2007

반도체 기술이 초고집적화 되어감에 따라 미세화공정에 의하여 소자의 크기가 급격히 줄어들고 있으며, 공정에서는 선폭이 크게 줄어드는 추세이다. 또한 박막을 다층으로 제조하여 소자의 집적도를 높이는 것이 중요한 이슈가 되고 있다. 이와 같은 수많은 제조 공정을 거치는 동안, Si 기판과 금속 박막사이에는 확산에 의한 많은 문제점들이 발생되고 있기 때문에, 이러한 금속과 Si 사이의 확산을 방지하는 것이 큰 이슈로 부각되어 왔다. 특히 Cu는 낮은 온도에서도 Si과 확산을 일으켜 Si 기판과 접합에서 확산에 의한 소자 failure 등이 문제로 발생하게 되며, 또한 선폭이 줄어듦에 따라 고열이 발생하여 실리콘으로 spiking이 발생하게 된다. 이를 방지하기 위하여 본 논문에서는 질소와 탄소를 첨가한 3개의 화합물로 구성된 Tungsten-Carbon-Nitrogen (W-C-N) 확산방지막을 사용하였다. 실험은 물리적 기상 증착법(PVD)으로 질소비율을 변화하며 확산방지막을 증착하였고, 이를 여러 가지 온도에서 열처리하여 열적인 안정성에 대한 실험을 실시하였다. 결정구조를 확인하기 위하여 X-ray Diffraction 분석을 통하여 확산방지막의 특성을 연구하였다.

• Bulletin of the Korean Chemical Society
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• 제33권4호
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• pp.1259-1263
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• 2012

Two metal compounds, $[Co(phen)_2(H_2O)_2]{\cdot}2H_2SIP{\cdot}2H_2O$ 1 and $[Ni(phen)_3]{\cdot}2H_2SIP{\cdot}3H_2O$ 2, have been obtained by incorporating 1,10-phenanthroline (phen) and 5-sulfoisophthalic acid monosodium salt ($NaH_2SIP$) ligands under hydrothermal conditions. Meanwhile, the two compounds were characterized by element analysis, IR, XRD, TG-DTA and single-crystal X-ray diffraction. Both 1 and 2 present 3D supramolecular structures via O-H${\cdots}$O hydrogen bond interactions. Luminescent properties for 1 and 2 were also studied. The compound 1 has two fluorescence emission peaks centered at 398 nm attributed to the intraligand emission from the SIP ligand and at 438 nm assigned to the combined interaction of intraligand ${\pi}^*-{\pi}$ transitions of the phen ligand and ligand-to-metal-charge-transfer (LMCT) transitions (${\lambda}_{ex}$ = 233 nm). The compound 2 shows one emission band centered at 423 nm with a shoulder peak at 434 nm which may be originated from the intraligand ${\pi}^*-{\pi}$ transitions of the phen ligand (${\lambda}_{ex}$ = 266 nm).

• 자원리싸이클링
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• 제3권1호
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• pp.9-16
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• 1994

Stellite 스크랩을 용융 NaOH로 분해하고 이로부터 Co가분말을 제조하였다. NaOH에 의한 Stellite 스크랩의 완전분해는 $750~800^{\circ}C$에서 Stellite에 대한 NaOH의 중량비 약 2로 1시간 이내에 이루어졌다. 함Co화합물은 X-선분석과 시차열중량분석에 의해 $Co_2O_3{\dot}H_2O$로 판명되었다. 함Co화합물은 HCl로 용해하여 $CoCl_2$용액으로 만들고, 그리고 용액의 pH를 조절하여 먼저 Fedldhs을 제거한 후, pH 약 13 또는 4에서 각각 2가 EH는 3가의 수산화코발트로 침전시켰다. 이 침전물들은 $400~500^{\circ}C$에서 수소로 환원하여 1.0~$1.5\mu\textrm{m}$크기의 고순도 Co로 제조되었다. Stellite스크랩으로부터 Co 회수율은 약 75~86 중량 %이었다.

• 대한금속재료학회지
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• 제47권12호
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• pp.811-818
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• 2009

In order to meet increasingly complex and rigorous technical specifications, extensive effort has been devoted to fabricate clad materials with multi-layered metal plates. In this study, novel stainless steel/aluminum/copper (STS/Al/Cu) three-ply clad materials were fabricated by a hot rolling process for cookware applications. The effect of the testing temperature on the mechanical properties of the clad materials and on each component metal was investigated during the tensile tests. The interface properties of the clad materials were also examined by optical microscopy (OM) and an electron probe micro-analyzer (EPMA). The best mechanical and interfacial properties for a warm working process were found in a sample annealed at a temperature of $300^{\circ}C$. For the sample annealed at $400^{\circ}C$, the results of the tensile test indicated that interface delamination occurred only in the region of the Al/Cu interfaces. This was due to the formation of the thick and brittle intermetallic compound of $Al_2Cu$ in the Al/Cu interface. In contrast, no interface delamination was observed in the STS/Al interface, most likely due to its strong bond strength.

• 한국건축시공학회지
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• 제1권2호
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• pp.185-190
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• 2001

The purpose of this study is the development of practical Dry floor tile unit method that settle the defect of a wet method and designed for resin mat. With use of PE resin which is confirmed the basic property, it is developed that resin mat, joint-sealing compound with fixed form and space management to Dry floor tile unit method. The result of this study is below. 1) To acquire above the 4kgf/$\textrm{cm}^2$ - construction specification criterion, the bonding space that between resin mat and tile has to occupy the 50% of resin mat module space(10,000$\textrm{cm}^2$). 2) Criteria of bonding part plane is below. simpleness of metal form. productivity, uniform quality after injection molding cooling, easy cutting for remain space management, adhesive property, construction ability, transformation of a severed piece under pressure and so on. 3) To get the shape that could protect the interfacial breakdown, it is designed that resin mat and tile are unified after the bond input. 4) Adapted joint-sealing compound is the material of urethane kinds wedge form. Resin mat has the water passageway that could drain the water. 5) To manage the severed piece of tile, the resin mat is likely to divide the half and the quarter and the plastic drainage is developed in the severed piece.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.438-439
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• 2006

Porcelain insulators have generally been used in Korea to insulate a transmission line from the tower, and a highly polymerized compound polymer insulator which has superior stain proof characteristics, has also been used widely. Currently, a worker rides on the suspension insulator string for installation on towers and conductors but in case of polymer insulators, this will pollute and scratch the housing result in durability reduction by deterioration and corona. This study developed a high strength aluminum compound metal lauder designed to work on polymer insulators without riding, and a clamp type connecting device and safety gear for easy installation on the tower and conductor. These polymer insulator work device can be used for 154kV and 345kV polymer insulators through a strength and load test to secure safety. This paper presents field usage.

• Journal of Welding and Joining
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• 제21권2호
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• pp.97-101
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• 2003

The change of microstructures in the base metal during transient liquid phase bonding process of directionally Ni base superalloy, GID-111 was investigated. Bonds were fabricated using a series of holding times(0~7.2ks) at three different temperatures. The flip chip bonding utilizing self-aligning characteristic of solder becomes mandatory to meet tolerances for the optical device. In this paper, a parametric study of aging condition and pad size of samples was evaluated. A TiW/Cu/electroplated Cu UBM structure was selected and the samples were aging treated to analyze the effect of intermetallic compounds with the time variations. An FIB technique was applied to the preparation of samples for TEM observations. An FIB technique is very useful to prepare TEM thin foil specimens from the solder joint interface. After aging treatment, the tendency to decrease in shear strength was measured and the structure of the solder and the UBM was observed by using SEM, TEM and EDS. As a result, the shear strength was decreased of about 21% in the 100${\mu}{\textrm}{m}$ sample at 17$0^{\circ}C$ aging compared with the maximum shear strength of the sample with the same pad size. In the case of the 12$0^{\circ}C$ aging treatment, 18% of decrease in shear strength was measured at the 100${\mu}{\textrm}{m}$ pad size sample. An intermetallic compound of Cu6Sn5 and Cu3Sn were also observed through the TEM measurement by using.

• 한국진공학회지
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• 제8권4B호
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• pp.514-518
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• 1999

Gold (Au) is not supposed to react with sapphire(single crystalline ) under thermodynamic equillibrium, therefore, a strong adhesion between these two dissimilar materials is not expected. However, pull test showed that the gold film sputter-deposited onto annealed and pre-sputtered sapphire exhibited very strong adhesion even without post-deposition annealing. Strongly and weakly adhered samples as a result of the pull testing were selected to investigate the adhesion mechanisms with Auger electron spectroscopy. The Au/ interfaces were analyzed using a new technique that probes the interface on the film using Auger electron escape depth. It revealed that one or two monolayers of Au-Al-O compound formed at the Au/Sapphire interface when AES in the UHV chamber. It showed that metallic aluminum was detected on the surface of sapphire substrates after irradiating for 3 min. with 7keV Ar+ -ions. These results agree with TRIM calculations that yield preferential ion-beam etching. It is concluded that the formation of Au-Al-O compound, which is responsible for the strong metal-ceramic bonding, is due to ion-induced cleaning and reduction of the sapphire surface, and the kinetic energy of depositing gold atoms, molecules, and micro-particles as a driving force for the inter-facial reaction.

• 한국주조공학회지
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• 제38권3호
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• pp.55-59
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• 2018

To optimize the conductivity and to reduce the weight by as much as possible, Al-Cu composites were prepared through a suction-casting procedure. Pure copper metal foam was infiltrated by melted aluminum with the use of the vacuum, after which warm rolling was conducted to remove several remaining pores at the interface between the Cu foam and the aluminum matrix. Despite the short casting time, significant dissolution of Cu into the melt was observed. Moreover, it was found that various Al-Cu intermetallic compounds arose at the interface during the isothermal heating process after the casting and rolling steps. The average thickness of the Al-Cu intermetallic compound tended to increase in proportion to the heating time. The electrical and thermal conductivity levels of the cast composites were found to be comparatively low, mainly due to the dissolution of the Cu foam and the formation of intermetallics at the interface.

• 열처리공학회지
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• 제16권1호
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• pp.2-9
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• 2003

The aluminum alloy which is light and has excellent thermal conductivity and iron base alloy that is remarkable heat-resistece and wear resistence properties were bonded together. The bond was created between a stationary and a rotating member by using the frictional heat generated between them while subjected to high normal forces on the interface of Al alloy and iron base alloy. The microstructure of the bonded interface of friction welding and the strength in the bonded interface formed under various bonding conditions were examined through TEM, SEM with EDX and triple bending test. In interface of bonding materials formed after various heat treatment, bonding strength was substantially different, resulting from formation of intermetallic compound or softening during annealing.