• Journal of the Korean Professional Engineers Association
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• v.16 no.1
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• pp.39-47
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• 1983

전자산업의 발전은 전자분야 자체뿐 아니라, 관련 전산업분야의 발진을 기초로 카는 것이며, 납땜성이 뛰어난 전기 주석 도금 System의 개발도 그 일익을 담당하게 되는 것이다. 그러나 주석도금 System의 종류와 방법에 따라서 납땜성의 차이는 아주 크며, 그 이유는 주석도그에 사용된 첨가제의 동시전착에 큰 영향이 있음을 알게 되었다. 본 조사는 납땜이 뛰어난 반광택 산성주석도금 방법에 대한 것으로 그 첨가제의 개발 및 사용방법을 기술하고 있다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.219-220
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• 2015

주석도금폐액으로부터 이온교환수지를 이용하여 주석을 회수하는 연구를 하였다. 주석 흡착이 가능한 3종류의 이온교환수지를 사용하여 기초 실험한 결과 tertiary기능기를 가진 이온교환수지는 주석을 흡착하지 못하였고, iminodiacetic 기능기를 가진 이온교환수지는 주석의 흡착률은 높으나, 불순물 함량이 높았으며, ethylhexyl-phosphar의 기능기를 가진 이온교환수지는 주석의 흡착률은 낮으나 pH 조절에 따라 불순물의 제어가 가능하였다.

• The korean journal of orthodontics
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• v.27 no.3 s.62
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• pp.493-502
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• 1997

This study was conducted to evaluate the tensile bond strength by bonding the dental bracket with Super-bond after treating the surface of dental Nickel-Chromium alloy with sandblasting, sandblasting & tin-plating, respectively, and tin-plating. 10 pieces of Nickel-Chromium alloys with brackets bonded with Super-bond without their surface treatment were sampled as a control group, 20 pieces of Nickel-Chromium alloy brackets bonded with Super-bond after treating them with sandblasting as group I, 20 pieces of Nickel-Chromium alloys tin-plated and bonded with Super-bond after sandblasting as group II, and then 20 pieces of alloys with brackets bonded with Super-bond after tin-plating as group III. The result of those examination and comparison is summarized as follows: 1. Group I showed the mean tensile bond strength of $14.41{\pm}2.24MPa$ which was highest among 4 groups, followed by group III($13.59{\pm}.51MPa$), group II($12.27{\pm}.45MPa$), and control group($10.50{\pm}1.57MPa$), respectively. However, it was shown that there was no statistically significant difference between group I and III, group III and II, and group II and control group(p>0.05). 2. The main failure pattern of those brackets showed that $70\%$ of the control group had an adhesive failure at the bracket-Superbond interface, and $30\%$ at the Nickel-Chromium alloy-Superbond interface, while other groups did the adhesive failure at the bracket-Superbond interface. 3. When examined under SEM, it was shown that adhesives were mostly attached to the surface of the Nickel-Chromium alloy for all groups while a considerable quantity of adhesives were attached to the bracket base. Then, those samples treated only with sandblasting showed the most even and remarkable roughness of their surface.

• Journal of the Microelectronics and Packaging Society
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• v.28 no.1
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• pp.47-54
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• 2021

For the bonding of smaller PCB solder bumps of less than 100 microns, an experiment was performed to make up a tin plating solution and find plating conditions in order to produce a bump pattern through tin electroplating, replacing the previous PCB solder bumps process by microballs. After SR patterning, a Cu seed layer was formed, and then, through DFR patterning, a pattern in which Sn can be selectively plated only within the SR pattern was formed on the PCB substrate. The tin plating solution was made based on methanesulfonic acid, and hydroquinone was used as an antioxidant to prevent oxidation of divalent tin ions. Triton X-100 was used as a surfactant, and gelatin was used as a grain refiner. By measuring the electrochemical polarization curve, the characteristics of organic additives in Triton X-100 and gelatin were compared. It was confirmed that the addition of Triton X-100 suppressed hydrogen generation up to -1 V vs. NHE, whereas gelatin inhibited hydrogen generation up to -0.7 V vs. NHE. As the current density increased, there was a general tendency that the grain size became finer, and it was observed that it became finer when gelatin was added.

• Journal of the Korean Professional Engineers Association
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• v.16 no.3
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• pp.68-73
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• 1983

The metal deposition behavior in the barrel tin plating has been studied for the electronic DIP products, and tried to find out some modified factors in order to explain partial ,current flow behavior of this load. The deposition distribution characteristics for DTP products should be classified with the normal barrel plating as partially conductive load. Deposit distribution curves obtained from one-dimensional model have shown strong dependence n the applied current density, rotating speed of barrel and metal ion concentration of the solution. Theoretical formula J=$\delta$'/${\beta}$-{-c$^3$/${\gamma}$-exp-(1-${\alpha}$)n${\Phi}$} derived from one-dimensional porous model has been proposed for the barrel plating behavior where higher overpotential and concentration changes take place during barrel plating.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2000.11a
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• pp.1-2
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• 2000

In chip plating, several parameters must be taken into consideration. Current density, solution concentration, pH, solution temperature, components volume, chip and media ratio, barrel geometrical shape were most likely found to have an effect to the process yields. The 3 types of barrels utilized in chip plating industry are the onventional rotating barrel, vibrational barrel(vibarrel), and the centrifugal type. Conventional rotating barrel is a close type and is commonly used. The components inside the barrel are circulated by the barrel's rotation at a horizontal axis. Process yield has known to have higher thickness deviation. The vibrational barrel is an open type which offers a wide exposure to electrolyte resulting to a stable thickness deviation. It rotates in a vertical axis coupled with multi-vibration action to facilitate mixed up and easy transportation of components. The centrifugal barrel has its plated work centrifugally compacted against the cathode ring for superior electrical contact with simultaneous rotary motion. This experiment has determined the effect of barrel vibration intensity to the plating thickness distribution. The procedures carried out in the experiment involved the overall plating process., cleaning, rinse, Nickel plating, Tin-Lead plating. Plating time was adjusted to meet the required specification. All other parameters were maintained constant. Two trials were performed to confirm the consistency of the result. The thickness data of the experiment conducted showed thatbthe average mean value obtained from higher vibrational intensity is nearer to the standard mean. The distribution curve shown has a narrower specification limits and it has a reduced variation around the target value. Generally, intensity control in vi-barrel facilitates mixed up and easy transportation of components. However, it is desirable to maintain an optimum vibration intensity to prevent solution intrusion into the chips' internal electrode. A cathodic reaction can occur in the interface of the external and internal electrode. 2H20 + e $\rightarrow$M/TEX> 20H + H2.. Hydrogen can penetrate into the body and create pressure which can cause cracks. At high intensity, the chip's motion becomes stronger, its contact between each other is delayed and so plating action is being controlled. However, the strong impact created by its collision can damage the external electrode's structure there by resulting to bad plating condition.

• The korean journal of orthodontics
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• v.21 no.1 s.33
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• pp.7-16
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• 1991

To estimate the possibility of the application of TiN ion-plating to the orthodontic appliance, colorimetric properties, and characteristics of ion-plated film as well as adhesive strength of TiN film to the substrate and mechanical properties of ion-plated orthodontic appliance were investigated. The obtained results were as follows: 1) TiN ion-plated film had the colorimetric properties which were the hue of about 2.5 Y, the brightness of about 6, and the chroma of about 4 by the standard color chip of JIS. 2) TiN ion-plated film was $2{\mu}m$ in thickness and its deposition pattern was rather irregular. 3) TiN phase was confirmed on the X-ray diffraction pattern. 4) Critical load for delamination of ion-plated film from stainless steel band was 10N. 5) Tensile and yield strength of ion-plated specimen was increased about 10Kg $f/mm^2$, while elongation was decreased $1\%$ compairing to the values of the non ion-plated specimen.

• Journal of the Korean institute of surface engineering
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• v.36 no.2
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• pp.168-175
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• 2003

The purpose of solder plating on chip external electrode is to provide a proper solderability to chips on PCB's. The quantitative or qualitative analysis of solderability has been performed by destructive methods, reflow or flow. Evidently, the solderability tends to depend on the grain structure which is varied with additives. Research on the feasibility of employing electrochemical techniques to characterize the solderability of electroplated tin - lead, with respect to the additives, was non destructively performed. The deposit morphology and the polarization behavior of electrolytes containing proprietary additives were evaluated to investigate the soldering degradation. The plated panels from synthetic electrolyte were analyzed according to % Sn, plating thickness, deposit appearance, grain structure, solderability and cyclic voltammetry.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2002.05a
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• pp.43-43
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• 2002

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2001.11a
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• pp.70-70
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• 2001