• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2002년도 추계기술심포지움논문집
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• pp.49-53
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• 2002

The Sn-Cu eutectic solder bump formation ($140{\mu}{\textrm}{m}$ diameter, $250{\mu}{\textrm}{m}$ pitch) by electroplating was studied for flip chip package fabrication. The effect of current density and plating time on Sn-Cu deposit was investigated. The morphology and composition of plated solder surface was examined by scanning electron microscopy. The plating thickness increased with increasing time. The plating rate increased generally according to current density. After the characteristics of Sn-Cu plating were investigated, Sn-Cu solder bumps were fabricated on optimal condition of 5A/dm$^2$, 2hrs. Ball shear test after reflow was performed to measure adhesion strength between solder bump and UBM (Under Bump Metallization). The shear strength of Sn-Cu bump after reflow was higher than that of before reflow.

• 소성∙가공
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• 제15권5호
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• pp.366-372
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• 2006

The effect of coating time in arc ion plating on surface properties of the TiN-coated high speed steel(SKH51) is presented in this paper. Surface roughness, micro-hardness, coated thickness, atomic distribution of TiN and adhesion strength are measured for various coating times. It has been shown that the coating time has a deep influence on the micro-hardness, the coated thickness, the atomic distribution of Ti and the adhesion strength of the SKH51 steels but that it has little influence on the surface roughness.

• 한국기계가공학회지
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• 제10권5호
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• pp.44-50
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• 2011

The effect of deposition time in arc ion plating on surface properties of the TiN-coated SM45C steel is presented in this paper. The surface roughness, micro-particle, micro-hardness, coated thickness, atomic distribution of TiN, and adhesion strength are measured for various deposition times. It has been shown that the deposition time has a considerable effect on the micro-hardness, the coated thickness, and the atomic distribution of TiN of the SM45C steels but that it has little influence on the surface roughness and adhesion strength.

• Clinics in Shoulder and Elbow
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• 제6권1호
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• pp.44-49
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• 2003

Purpose: Many different operative technique of mid-shaft clavicle fracture have been reported. The aim of this prospective study was to compare the results of anterior or anterior-inferior plating with superior plating on the acute mid-shaft fracture of clavicle Materials and Methods: From February1997 to February 2002, thirty-eight consecutive open reduction and internal fixation with reconstruction plates were performed in thirty-eight patients. from August 1999, anterior or anterior-inferior plating was mainly used, prospectively. The duration of follow-up averaged 17 months (range,23 to 43 months). The mean age was 38 years old (range,21 to 57 years old) on anterior or anterior-inferior plating group and 35 years old (range,24 to 55 years old) on superior plating group. The physician progress note, VAS patient complement score, Roentgenogram and ASES score was evaluated. Results: Four patients were lost to follow-up. There was no statistical difference on mean radiological bone union time （8.7 weeks vs. 8.6 weeks) and ASES score (92 vs 94) at inferior and superior plating groups (P > 0.05). VAS patient complement score was very good or excellent on anterior or anterior-inferior group, average score was 1.1 (ranger,0 to 2) compare with superior plating group (P < 0.05). There were two cases of infection, 1 case of failed fixation on superior plating group and 1 case of delayed union on anterior inferior plating group. Conclusion: Anterior inferior plating on acute clavicle midshaft fracture results in excellent patient complement score compare with conventional superior reconstruction plate.

• 대한족부족관절학회지
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• 제15권3호
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• pp.153-158
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• 2011

Purpose: This study was performed retrospectively and to compare the clinical outcomes of the surgical management using Antiglide plating and lateral plating for Danis-Weber type B isolated lateral malleolar fractures. Materials and Methods: Between March 2004 and March 2009, 92 patients were followed up for more than 6 months after surgical treatment. 49 patients were treated with Antiglide plating, whereas the remaining 43 patients underwent lateral plating. The results of the two groups were analyzed both radiographically and clinically using Ankle scoring system. Results: Both groups were comparable for age, sex distribution, time to surgery, and operation time. Bone union was noted at average of 8 weeks in all fractures. The mean ankle score was similar in both groups (94% versus 93%). Conclusion: Antiglide plating for Danis-Weber type B isolated lateral malleolar fracture is one of the good methods which has some advantages such as early ankle motion, ambulation and smaller operative incision.

• 환경위생공학
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• 제17권3호
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• pp.37-45
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• 2002

The Purpose of this study is to reduce environmental problems caused by landfill of bituminous coal fly ash emitted from the power plant and to reuse it. First of all, we experimented that Al and Si elements were extracted from fly ash and investigated that extracted Al and Si elements night use a coagulant. The extraction was carried out under various conditions ; concentration of the extraction solution, calcination temperature and calcination time. As the results, it was found that the optimum conditions of the extraction of Al and Si elements from fly ash were as follows, concentration of NaOH was 5N for both of them, calcination temperature was $700^{\circ}C$ and $600^{\circ}C$ and calcination time was 1hr and 1.5hr, respectively The extracted solution was used as a coagulant to treat the diluted metal-plating solutions which contained Pb and Cu, respectively. As the result of treatment on the diluted Pb-plating solution with 315NTU, the removal efficiency of turbidity was more than 90%, and the removal efficiency of Pb was about 80%. As for treatment of the non-turbid diluted Cu-plating solution, the removal efficiency of Cu was about 98%.

• 마이크로전자및패키징학회지
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• 제22권1호
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• pp.51-54
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• 2015

An electro-plating technology on a cured isotropic conductive pattern with a hybrid Cu paste composed of resin matrix, copper, and solder powders has been developed. In a conventional technology, Ag paste was used to perform a conductive pattern on a PCB or silicon substrate. From previous research, the electrical conductive mechanism and principle of the hybrid Cu paste were concisely investigated. The isotropic conductive pattern on the PCB substrate was performed using screen-printing technology. The optimum electro-plating condition was experimentally determined by processing parameters such as the metal content of the hybrid Cu paste, applied current density, and time for the electroplating in the plating bath. The surfaces and cross-sections were observed using optical and SEM photographs. In conclusion, the optimized processing conditions for Cu electro-plating technology on the conductive pattern were a current density of $40mA/cm^2$ and a plating time of 20min on the hybrid Cu paste with a metal content of 44 vol.%. More details of the mechanical properties and processing conditions will be investigated in further research.

• 청정기술
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• 제11권3호
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• pp.153-164
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• 2005

This study found a reliable evaluation for four kinds of pb-Free plating solutions and it's layers, through pure Sn, SnAg, SnBi and SnCu. These four kind of solutions are widely used to pb-Free plating. Hull-cell, Harring-blum, coverage, throwing power, current efficiency, stability, life-time, composition, hardness, roughness, abrasion, scratch, solderability, corrosion, contact angle, morphology, SIR(Surface insulation resistance) and Whisker test were experimented. Also, Using ICP, XRF, FE-SEM, EDS, temperature/humidity chamber, solderability tester, hardness tester, roughness tester, abrasion tester, salt spray tester, contact angle tester, SIR tester, and microscope. In this paper could be shown the systematic and various analysis for reliability about four kinds of pb-Free plating solutions, processes and it's deposit surface.

• 전기학회논문지
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• 제65권3호
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• pp.445-451
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• 2016

General fuse elements of solution for fast acting operation characteristics made using silver or silver alloy, those are not able to dominate cost competition to the advanced global leaders that have not only high technology but competitive price. In this study, the method that compose the fuse elements manufactured solution of fast acting operation characteristics by using precision multi-layer thin film plating and helical cutting process from low-priced copper metal. Furthermore, in order to move rated current line of fuse due to the heat loses, the manufacture construction method of fixed resistor is introduced, and then Ni-P plating layer and Sn plating layer are introduced multiply for controling fine opening time characteristics. So this study can establish the high productive and low-priced production method.

• 마이크로전자및패키징학회지
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• 제26권2호
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• pp.51-54
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• 2019

실리콘 기판상에 여러 조건의 전류밀도에서 로듐 도금을 실시하였다. 직류전원의 경우 전류밀도가 증가하면 로듐 표면에 균열이 발생하였다. 잔류응력을 낮추기 위하여 펄스전류를 인가하였다. 펄스전류의 off 시간이 도금층의 잔류응력을 낮추는데 영향을 주었다. 펄스전류의 인가 주기를 5:5로 하였을 경우 균열 없는 로듐 도금층을 얻었다.