• Journal of the Korean Ceramic Society
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• v.52 no.4
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• pp.264-268
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• 2015

Cu films were plated in an eco-friendly electroless bath (No-Formaldehyde) on Ni/screen printed Ag pattern/PET substrate. For electroless Cu plating, we used sodium-phosphinate ($NaH_2PO_2{\cdot}H_2O$) as reducing agent instead of Formaldehyde. All processes were carried out in electroless solution of pH 7 to minimize damage to the PET substrate. According to the increase of sodium-phosphinate, the deposition rate, the granule size, and rms roughness of the electroless Cu film increased and the Ni content also increased. The electroless Cu films plated using 0.280 M and 0.575 M solutions of sodium-phosphinate were made with Cu of 94 at.% and 82 at.%, respectively, with Ni and a small amount P. All electroless Cu plated films had typical FCC crystal structures, although the amount of co-deposited Ni changed according to the variation of the sodium-phosphinate contents. From these results, we concluded that a formation of higher purity Cu film without surface damage to the PET is possible by use of sodium-phosphinate at pH 7.

• Journal of the Korean institute of surface engineering
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• v.24 no.4
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• pp.187-195
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• 1991

Adhesion strength of electroless-plated Ni, Ni-P and Cu deposites on alumina substrate has been studied. Grain boundary spaces produced on the substrate surface by etching treatment provided anchoring sites for enhancing the adhesion strength. Adhesion strengths of Ni-P and Ni deposit were higher than that of Cu deposit, because of higher initial nucleation rates than the latter. The electroless-plated Ni-P and Ni underlayer improved the adhesion strength of the Cu deposit. In could be attributed to the enhanced adhesion between the substrate and those underlayers as well as the satisfactory adhesion between Cu deposits and those underlayers. Heat treatment was also conducted in order to enhance the adhesion strength of Cu layer. The strength was enhanced by about 19% when the treatment was conducted at $150^{\circ}C$ for 2 hours. The enhancement was attributed to relief of internal stress and release of hydrogen.

• Polymer(Korea)
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• v.27 no.1
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• pp.52-60
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• 2003

In this work, two types of Ni-plating, namely electrolytical and electroless Ni-platings on carbon fiber surfaces, were carried out to enhance the impact resistance of composites. And the comparison between electrolytical and electroless methods on their impact properties of composite system was studied. The surface properties of carbon fibers were characterized using XRD, SEM, and contact angle measurements. The impact behaviors were investigated using an Izod type impact tester. As experimental results, it was observed that electrolessly plated Ni layers had Ni-P alloys on carbon fiber surfaces as revealed by XRD, and electrolytically Ni-plated carbon fibers showed higher surface free energies than those of the electrolessly Ni-plated carbon fibers. In particular, the impact strengths of electrolessly Ni-plated carbon fibers-reinforced plastics were strongly increased. These results were probably due to the difference of wettabilities according to the different types of Ni-plating methods.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2001.07a
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• pp.95-99
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• 2001

Cu is considered as a promising alternative interconnection material to Al-based interconnection materials in Si-based integrated circuits due to its low resistivity and superior resistance to the electromigration. New humping and UBM material systems for solder flip chip interconnection of Cu pads were investigated using electroless-plated copper (E-Cu) and electroless-plated nickel (E-Ni) plating methods as low cost alternatives. Optimally designed E-Ni/E-Cu UBM bilayer material system can be used not only as UBMs for solder bumps but also as bump itself. Electroless-plated E-Ni/E-Cu bumps assembled using anisotropic conductive adhesives on an organic substrate is successfully demonstrated and characterized in this study

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.350-355
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• 2009

The crysralline silicon solar cell where the solar cell market grows rapidly is occupying of about 85% or more high efficiency and low cost endeavors many crystalline solar cells. The fabricaion process of high efficiency crystalline silicon solar cells necessitate complicated fabrication processes and Ti/Pd/AG contact, This metal contacts have only been used in limited areas in spite of their good srability and low contact resistance because of expensive materials and process. Commercial solar cells with screen-printed solar cells formed by using Ag paste suffer from loe fill factor and high contact resistance and low aspect ratio. Ni and Cu metal contacts have been formed by using electroless plating and light-induced electro plating techniques to replace the Ti/Pd/Ag and screen-printed Ag contacts. Copper and Silver can be plated by electro & light-induced plating method. Light-induced plating makes use the photovoltaic effect of solar cell to deposit the metal on the front contact. The cell is immersed into the electrolytic plating bath and irradiated at the front side by light source, which leads to a current density in the front side grid. Electroless plated Ni/ Electro&light-induced plated Cu/ Light-induced plated Ag contact solar cells result in an energy conversion efficiency of 16.446 % on 0.2~0.6${\Omega}$ cm, $20{\times}20mm^2$, CZ(Czochralski) wafer.

• Korean Journal of Metals and Materials
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• v.47 no.10
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• pp.675-680
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• 2009

Effects of $85^{\circ}C/85%$ Temperature/Humidity (T/H) treatment conditions on the peel strength of an electroless-plated Ni/polyimide system were investigated from a $180^{\circ}$ peel test. Peel strength between electroless-plated Ni and polyimide monotonically decreased from $37.4{\pm}5.6g/mm$ to $22.0{\pm}2.7g/mm$ for variation of T/H treatment time from 0 to 1000 hrs. The interfacial bonding mechanism between Ni and polyimide appears to be closely related to Ni-O bonding at the Ni/polyimide interface. The decrease in peel strength due to T/H treatment appears to be related to polyimide degradation due to moisture penetration through the interface and the bulk polyimide itself.

• Korean Journal of Materials Research
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• v.23 no.11
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• pp.661-665
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• 2013

We investigated the characteristics of electroless plated Cu films on screen printed Ag/Anodized Al substrate. Cu plating was attempted using neutral electroless plating processes to minimize damage of the anodized Al substrate; this method used sodium hypophosphite instead of formaldehyde as a reducing agent. The basic electroless solution consisted of $CuSO_4{\cdot}5H_2O$ as the main metal source, $NaH_2PO_2{\cdot}H_2O$ as the reducing agent, $C_6H_5Na_3O_7{\cdot}2H_2O$ and $NH_4Cl$ as the complex agents, and $NiSO_4{\cdot}6H_2O$ as the catalyser for the oxidation of the reducing agent, dissolved in deionized water. The pH of the Cu plating solutions was adjusted using $NH_4OH$. According to the variation of pH in the range of 6.5~8, the electroless plated Cu films were coated on screen printed Ag pattern/anodized Al/Al at $70^{\circ}C$. We investigated the surface morphology change of the Cu films using FE-SEM (Field Emission Scanning Electron Microscopy). The chemical composition of the Cu film was determined using XPS (X-ray Photoelectron Spectroscopy). The crystal structures of the Cu films were investigated using XRD (X-ray Diffraction). Using electroless plating at pH 7, the structures of the plated Cu-rich films were typical fcc-Cu; however, a slight Ni component was co-deposited. Finally, we found that the formation of Cu film plated selectively on PCB without any lithography is possible using a neutral electroless plating process.

• Carbon letters
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• v.14 no.4
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• pp.243-246
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• 2013

In this work, electroless Ni-plating on polyethylene terephthalate (PET) ultra-fine fibers surfaces was carried out to improve the electric conductivity of the fiber. The surface properties of PET ultra-fine fibers were characterized using scanning electron microscopy, X-ray diffraction, and contact angle analyses. The electric conductivity of the fibers was measured using a 4-point testing method. The experimental results revealed the presence of island-like nickel clusters on the PET ultra-fine fibers surfaces in the initial plating state, and the electric conductivity of the Ni-plated fibers was enhanced with increasing plating time and thickness of the Ni-layers on the PET ultra-fine fibers.

• Korean Journal of Materials Research
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• v.24 no.11
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• pp.632-638
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• 2014

We investigated the effects of DMAB (Borane dimethylamine complex, C2H10BN) in electroless Ni-B film with addition of DMAB as reducing agent for electroless Ni plating. The electroless Ni-B films were formed by electroless plating of near neutral pH (pH 6.5 and pH 7) at $50^{\circ}C$. The electroless plated Ni-B films were coated on screen printed Ag pattern/PET (polyethylene terephthalate). According to the increase of DMAB (from 0 to 1 mole), the deposition rate and the grain size of electroless Ni-B film increased and the boron (B) content also increased. In crystallinity of electroless Ni-B films, an amorphization reaction was enhanced in the formation of Ni-B film with an increasing content of DMAB; the Ni-B film with < 1 B at.% had a weak fcc structure with a nano crystalline size, and the Ni-B films with > 5 B at.% had an amorphous structure. In addition, the Ni-B film was selectively grown on the printed Ag paste layer without damage to the PET surface. From this result, we concluded that formation of electroless Ni-B film is possible by a neutral process (~green process) at a low temperature of $50^{\circ}C$.

• Journal of the Korean institute of surface engineering
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• v.48 no.4
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• pp.149-157
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• 2015

We investigated the effects of the fabric structure or the kinds of plated metals on the electromagnetic interference shielding effectiveness (EMI SE) by means of electroless plating on polyester fabric. We found that the weight of deposited metal, EMI SE, and flexibility of the conductive fabric for EMI shield is affected by morphology of fabric and structure of fiber. The EMI SE of conductive fabric plated Ni/Cu/Ni by electroless plating method on draw textured yarn (DTY) polyester was in the practically useful range of above 70 dB over a wide frequency range of 10 MHz to 1.0 GHz at the surface resistivity of $0.05{\Omega}/{\square}$. Au or Ag plated conductive fabric by immersion plating method is not able to provide for a good EMI SE.