Electroless nickel plating

About: Electroless nickel plating is a research topic. Over the lifetime, 1593 publications have been published within this topic receiving 14940 citations.

Initiation of Electroless Nickel Plating on Copper, Palladium‐Activated Copper, Gold, and Platinum

Abstract: The catalytic activity of copper, palladium-activated copper, gold, and platinum for electro-oxidation of hypophosphite and electroless nickel plating was investigated in an ammoniacal solution of pH 8.8 at 50/sup 0/C by potential measurements and linear sweep voltammetry from -0.3 to -0.92V vs. SCE. Early stages of nickel plating on copper-palladium substrates were studied by scanning electron microscopy in conjunction with EDAX. It was found that palladium-activated copper and gold were catalytically active in the entire range of potentials examined; copper was active below -0.6 platinum was not active at all. Small amounts of electrolytically deposited nickel considerably increased the electro-oxidation rate of hypophosphite on copper, gold, and palladium. TEM examinations showed that activation of copper in a PdCl/sub 2//HCl solution resulted in the deposition of palladium in the form of separate patches. Electroless nickel deposition on copper substrates with separate palladium spots took place on copper and palladium independently of each other. The deposition on palladium was faster than that on copper. It was concluded that the activation of copper substrates around palladium spots occurred solely through a spontaneous potential shift, induced by electro-oxidation of hypophosphite on the palladium spots. It was suggested that small amounts of one metal synergisticallymore » enhanced the catalytic activity of the other metals.« less

Electroless nickel plating on alumina ceramics

Abstract: Pour obtenir une bonne adherence du depot chimique de nickel sur des substrats en ceramique (96 a 99,5% d'alumine), on utilise comme traitements de preparation de la surface une attaque au fluorure d'ammonium suivie d'une sensibilisation au chlorure stanneux et d'une activation par du chlorure de palladium. Une composition appropriee et une purge du bain avec du gaz inerte ameliore l'adherence

Electroless nickel bumping of aluminum bondpads. II. Electroless nickel plating

Abstract: Electroless nickel has been used for many decades to provide a hard, corrosion resistant surface finish to engineering components. In recent years, its application has been extended to the electronics industry for the production of solderable surfaces on printed circuit boards, which utilize a further thin gold coating to prevent oxidation of the nickel surface. The recent interest in the use of flip-chip technology in electronics manufacture has required the development of low cost methods for solder bumping of semiconductor wafers. The electroless nickel process has been considered as a suitable candidate for the deposition of a solderable under bump metallization (UBM) layer onto the Al bondpads. However, the extension of existing electroless nickel plating processes to this new application requires greater understanding of the technique. In particular, the coating of the small isolated bondpads on the wafer surface introduces difficulties that make the use of many commercially available solutions impossible. This paper reports the results of a number of experiments carried out to investigate the electroless nickel bumping of Al bondpads and highlights the issues that need to be considered when selecting materials and techniques.

Electroless nickel plating on ZM6 (Mg–2.6Nd–0.6Zn–0.8Zr) magnesium alloy substrate

Abstract: To improve the corrosion resistance of ZM6 (Mg–2.6Nd–0.6Zn–0.8Zr) magnesium alloy, electroless nickel plating on ZM6 alloy with a new pretreatment process and nickel carbonate bath was investigated in this paper. The morphology, component, chemical composition and structure of the pretreatment layers and electroless nickel coating were analyzed using scanning electronic microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction spectroscopy. The adhesion and corrosion resistance of the Ni–P coating were evaluated by means of thermal shock, potentiodynamic polarization, and salt spray test. The results showed that a compact zinc immersion layer was formed on the surface of the ZM6 alloy in a new zinc dipping solution. The subsequent amorphous electroless nickel coating was uniform, in which the content of P was 9.7 wt.%. Its thickness reached about 62 μm at 2 h deposition. Compared with the bare substrate, the corrosion potential of the coated alloy shifted by 1075 mV positively and the corrosion current density decreased two orders of magnitude in 3.5 wt.% NaCl solution. The salt spray test time of Ni–P coating was 158 h. These results suggest that the electroless nickel plating procedure developed in the study is available for ZM6 alloy and the Ni–P coating obtained with good adhesion could protect the substrate effectively.