• Journal of Adhesion and Interface
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• v.4 no.2
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• pp.10-20
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• 2003

This paper is relative to the electroless deposition of nickel or copper films on polyimide and polytetrafluoroethylene substrates. First, it is presented an original approach of the electroless process which consists in grafting nitrogenated functionalities on the polymer surfaces via plasma or VUV-assisted treatments operating in a nitrogen-based atmosphere ($NH_3$, $N_2$), and then in catalysing the grafted surfaces in an aqueous tin-free, Pd(+2)-based solution. Adhesion of the Pd(+2) catalytic species on polymer surfaces is explained by the formation of strong covalent bonds between these species and the grafted nitrogenated groups. Second, it is show how a fragmentation test performed in conjunction with electrical measurements can be used to characterize the practical adhesion of the electroless coatings deposited on flexible polymer substrates, and to evidence the influence of some experimental parameters (plasma treatment time and nature of the gas phase).

• Textile Coloration and Finishing
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• v.22 no.1
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• pp.77-82
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• 2010

Highly conductive yarn was successfully obtained using electroless nickel plating method with palladium activation. In the presence of palladium seed on surface of fibers as a catalyst, continuos nickel layer produced on surface of fibers by reducing $Ni${2+}$ ion in the electroless plating bath to $Ni^0$. It was found that the Pd-activation using $SnCl_2$ and $PdCl_2$ to deposit palladium seeds on the surface of fibers plays a key role in the subsequent electroless plating of nickel. It also found that electroless nickel plating on the fibers can induce the nickel-plated $ELEX^{(R)}$ fibers to improve the electrical conductivity of the fibers. The thickness of nickel coating layer on the Pd-activated $ELEX^{(R)}$ fibers and specific conductivity of the fiber were increased through electroless plating time. The temperature of nickel plating bath was very effective to enhance the nickel deposition rate.

• Journal of the Korean institute of surface engineering
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• v.26 no.4
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• pp.175-182
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• 1993

Electroless plating of nickel was studied electrochemically in the presence of complexing agents. Nickel sulfate solution with dimethylamine borance(DMAB) as the reducing agent was used. Effects of temperature pH, concentration and complexing agents-citric acid, EDTA, tartaric acid-were studied.Experimental meas-urements showed that the rate of electroless nickel deposition was closely related to electrochemical parame-ters such as temdperature, pH, concentration and the properties of complexing agets.

• Journal of the Korean institute of surface engineering
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• v.24 no.4
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• pp.206-214
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• 1991

In the basic study of selective electroless Ni plating of Si wafers, plating rate and physical properties are investigated to obtain optimum conditions of contact hole filling. Si wafers are excellently activated in the concentration of 0.5M IF, 1mM PdCl2, 2mM EDTA at $70^{\circ}C$, 90sec. The optimum condition of Ni-B deposition on p-type Si wafers is 0.1M NiSO4, 0.11M Citrate, $70^{\circ}C$, pH6.8, 8mM DMAB. The main factor in the sheet resistences variation of films is amorphous and on heat treating matrix was transformed into a stable phase (Ni+Ni3B) at $300-400^{\circ}C$. But pH or DMAB concentration in the plating solution doesn't play role of heat-affected phase change.

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.120.2-120
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• 2003

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.179.2-179
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• 2002

• Journal of the Korean institute of surface engineering
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• v.28 no.2
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• pp.83-91
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• 1995

A new method for preparation of thin nickel foam for Ni-MH battery was investigated. In this method, fine graphite powders of $1\mu\textrm{m}$～$2\mu\textrm{m}$ diameter were pasted into pores of thin polyurethane foam film in order to supply electric conducting seeds for nickel deposition by electroless plating reaction. After electroless plating, remaining polyurethane foam was removed chemically by organic solvent treatment and graphite particles also removed by ultrasonic cleaning. Porosity of formed nickel foam was about 85% During electroplating, porosity of the nickel foam decreased less than 5% up to $30\mu\textrm{m}$ coating thickness. And then it was electroplated and heat-treated to improve mechanical strength and ductility. Finally, thin nickel foam for Ni electrode of Ni-MH battery with 80% porosity and $350\mu\textrm{m}$～X$400\mu\textrm{m}$ thickness was obtained.

• Transactions of Materials Processing
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• v.28 no.2
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• pp.77-82
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• 2019

Corrosion occurs well on surface of roll formed and Zn alloy subsequently electro-deposited on steel bolt under wet condition. In this study, variations in corrosion resistance were investigated through the measurement of polarization curves on steel bolts which were roll formed and subsequently coated with various types of coating methods. According to the measured polarization curve, Ni-P electroless deposits on roll formed steel increased the resistance to corrosion. The corrosion resistance of Zn alloy powder coated steel bolt was found to be better than that of Zn-Ni electro-deposited sample.

• Journal of Powder Materials
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• v.14 no.2 s.61
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• pp.108-115
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• 2007

Cu-Ni-P alloy nano powders were fabricated by the electrical explosion of electroless Ni plated Cu wires. The effect of applied voltage on the explosion was examined by applying pulse voltage of 6 and 28 kV, The estimated overheating factor, K, were 1.3 for 6 kV and 2.2 for 28 kV. The powders produced with pulse voltage of 6 kV were composed of Cu-rich solid solution, Ni-rich solid solution, and $Ni_3P$ phase. While, those produced with 28 kV were complete Cu-Ni-P solid solution and small amount of $Ni_3P$ phase. The initial P content of 6.5 at.% was reduced to 2-3 at.% during explosion due to its high vapour pressure.

• Journal of the Microelectronics and Packaging Society
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• v.11 no.3 s.32
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• pp.37-45
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• 2004

Electroless Ni(P) has been widely used for under bump metallization (UBM) of flip chip and surface finish layer in microelectronic packaging because of its excellent solderability, corrosion resistance, uniformity, selective deposition without photo-lithography, and also good diffusion barrier. However, the brittle fracture at solder joints and the spatting of intermetallic compound (IMC) associated with electroless Ni(P) are critical issues for its successful applications. In the present study, the mechanism of IMC spatting and microstructure change of the Ni(P) film were investigated with varying P content in the Ni(P) film (4.6,9, and $13 wt.\%$P). A reaction between Sn penetrated through the channels among $Ni_3Sn_4$ IMCs and the P-rich layer ($Ni_3P$) of the Ni(P) film formed a $Ni_3SnP$ layer. Thickening of the $Ni_3SnP$ layer led to $Ni_3Sn_4$ spatting. After $Ni_3Sn_4$ spatting, the Ni(P) film directly contacted the molten solder and the $Ni_3P$ phase further transformed into a $Ni_2P$ phase. During the crystallization process, some cracks formed in the Ni(P) film to release tensile stress accumulated from volume shrinkage of the film.