Influence of Complexing Agents in Electroless Nickel Strike Plating Solution for Solder Ball Shear Properties on Electroless Thin Ni/Au Plated Film.

Abstract

Electroless thin film nickel / gold plating processes have been applied to fine copper pattern surfaces. Generally, a palladium catalyst treatment is used as a pretreatment of electroless nickel plating. As described in earlier reports, using an electroless nickel strike plating solution without palladium catalyst improved the solder ball shear properties. Complexing agent selection of nickel strike plating solution was examined in this study to improve solder ball shear properties because the nickel complexing agent in the electroless nickel strike plating solution influences them. Results show that complexing agents with high chelating activity for nickel ions such as citric acid exhibit excellent solder ball shear properties.