• Journal of the Korean institute of surface engineering
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• v.51 no.6
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• pp.400-404
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• 2018

A metal 3D printer has been developed on its own to electrodeposit the localized area. Nozzles were used to selectively laminate the electrolytic plating method. To analyze the factors affecting the deposition, the stack height, thickness and surface roughness were experimentally analyzed according to the current density and the temperature of the electrolyte. Electrolytic temperature and current are electrodeposited when the deposition conditions are dominant over the etching conditions, but the thickness is kept constant. On the contrary, when the etching conditions are dominant, the electrodeposited shape is rather the etched. As a result, the uniformity of surface quality and electrodeposition rate could be improved by conducting experiments under constant conditions of electrolyte temperature and current density.

• Korean Journal of Materials Research
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• v.20 no.10
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• pp.555-558
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• 2010

This study examined the effect of current density on the surface morphology and physical properties of copper plated on a polyimide (PI) film. The morphology, crystal structure, and electric characteristics of the electrodeposited copper foil were examined by scanning electron microscopy, X-ray diffraction, and a four-point probe, respectively. The surface roughness, crystal growth orientation and resistivity was controlled using current density. Large particles were observed on the surface of the copper layer electroplated onto a current density of 25 mA/$cm^2$. However, a uniform surface and lower resistivity were obtained with a current density of 10 mA/$cm^2$. One of the important properties of FCCL is the flexibility of the copper foil. High flexibility of FCCL was obtained at a low current density rather than a high current density. Moreover, a reasonable current density is 20 mA/$cm^2$ considering the productivity and mechanical properties of copper foil.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.139-140
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• 2002

This paper discusses the effect of plating condition on the mechanical property of electroplated Cu film. Current density, the amount of the organic additives was found to affect the residual stress of electroplated copper film. The result show that, in the case of residual stress, the copper film deposited at higher additive result in lower residual stress and plating current by $15mA/cm^2$ induced a better result than any other ones.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.05a
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• pp.145-149
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• 1995

The metallization is the key to determining cell costs, call performance, and cell and system reliabiltiy. The Burled Contact Solar Cell (BCSC) was specifical1y desinged to be compatible tilth low cost, mass production techniques and avoid the conventional metallization problem. By using electroless plating trchniqeu, we performed this metallization inexpensively and reliabley, This paper presents the details of the optimization procedure of metallization schemes on laser grooved cell surface Commercially available Ni ,Cu, and Ag plating solutions were applied for the cell metallization. The application of those solutions on the buried contact front metalization has resulted in an cell efficiency of 18.5% The cell parameters are an open circuit voltage of 651 mV, short circuit current density of 38.6 mA/$\textrm{cm}^2$, and fill factor of 73.5%.

• BMB Reports
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• v.32 no.3
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• pp.266-272
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• 1999

The insulin-like growth factor (IGF) system consisting of IGF-I, IGF-II, IGF-receptors, and IGF-binding proteins (IGFBP) regulates the proliferation of a variety of cancer cell types. To examine whether a decrease in endogenous IGFBP-3 stimulates proliferation or inhibits differentiation, Caco-2 cells, a human colon adenocarcinoma cell line, were stably transfected with an anti-sense IGFBP-3 expression construct or pcDNA3 vector as control. Accumulation of IGFBP-3 mRNA and secretion of IGFBP-3 into serum-free conditioned medium, 9 days after plating, were significantly lower in Caco-2 cell clones transfected with anti-sense IGFBP-3 cDNA compared to the controls. The anti-sense clones grew at a similar rate to the controls for 8 days after plating, but achieved a higher final density between days 10 and 12. The levels of sucrase-isomaltase mRNA, a marker of enterocyte differentiation of Caco-2 cells, were lower in the anti-sense clones examined on day 9. In conclusion, proliferation of Caco-2 cells can be stimulated by lowering endogenously-produced IGFBP-3.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2003.11a
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• pp.118-121
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• 2003

The electrochemical behaviors of UBM nickel were investigated. Electrode potential has been changed with the surface composition. Zinc is dissolved into the solution immediately after immersion. Electrode potential has three distinct regions: Zinc dissolution region, transient region and nickel plating region. The effects additives on electrode potential and polarization curves were also investigated. The addition of suppressor lowered the current density which is related with deposition rate.

• Journal of Ocean Engineering and Technology
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• v.11 no.4
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• pp.49-60
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• 1997

This paper deals with the effect of coating layer on the fatigue strength of TiN coated 1Cr-1Mo-0.25V steel prepared by using the arc ion plating (AIP) process, in which it was characterized by the presence of extractor grid (ion filter). The rotary bending fatigue tests were carried out under room air conditions, and the fatigue crack initiation and growth bwhavior were observed by using plastic replica method. As experimental results, it was found that the obvious improvement of fatigue life at lower stress region was confirmed in TiN coated specimen processed with ion filter. It was also exlained that the increase of fatigue life in the case of an improved AIP process with ion filter was attributed to the retardation of crack initiation of the substrate surface due to hard coating layer, more densly formed with the reduced size and density of droplets.

• Journal of the Korean institute of surface engineering
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• v.46 no.4
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• pp.158-161
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• 2013

Recently, the weight reduction and miniaturization of the electronics have placed great emphasis. The miniaturization of PCB (Printed Circuit Board) as main component among the electronic components has also become progressed. The use of acid copper plating process for Via-Filling effectively forms interlayer connection in build-up PCBs with high-density interconnections. However, in the case of copper-via filled in a bath, which is greatly dependent on the effects of additives. This paper discusses effects of Cl ion on the filling of PCB vias with electrodeposited copper based on both electrochemical experiment and practical observation of cross sections of vias.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.232-233
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• 2015

The effects of various bath conditions such as surfactant concentration, bath pH, bath temperature, agitation of bath; as well as pulse parameters such as cathodic current density, pulse duty cycle and frequency, on the grain size, surface finish, and appearance of the tin plated coatings have been investigated. The plating bath under investigation is an aqueous acidic solution composed of a mixture of $SnSO_4$, $H_2SO_4$, and a surfactant. The bath conductivity and pH are measured by a glass pH electrode. The microstructure of the coatings produced is characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and surface profilometry. XRD analysis shows that the deposits consist of tetragonal ${\beta}$-Sn crystal structure irrespective of plating conditions. The mechanism involved in the morphology evolution in response to various parameters and conditions has also been discussed.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2011.05a
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• pp.184-185
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• 2011

In this study, in order to obtain a high reflectivity for the LED lead frame, tin dip coating and tin plating were conducted respectively, and wettability of LED lead frame with tin solder also was tested by wetting balance tester. A Cu sheet was plated in Cu brighten electroplating bath and followed by immersion in a Sn electro-less plating bath [1]. On the other hand, in the dip coating process, a Cu sheet was dipped into molten tin. In the progress of wetting test, besides wetting balance curve, the maximum measured force($F_m$), the maximum withdrawal force($F_w$) and zero-cross time($t_0$) were obtained in various temperatures. With the maximum withdrawal force, the surface tension was calculated at different temperatures. The Cu sheet plated with bright Cu and Sn show a silver bright property while that of Cu dipped with Sn possessed a high reflectance density of 1.34GAM at $270^{\circ}C$.