Showing papers by "Joseph Anthony Abys published in 2002"

Electroplating and Properties of SnBi and SnCu for Lead-Free Finishes

Abstract: SUMMARYTin alloys such as Sn-0.7% Cu and Sn-2%Bi were identified as viable alternatives to tin-lead finishes. Electroplating of these alloys is challenging because of the great difference in reduction potentials of the individual elements and the usual problems associated with strong immersion deposition and poor alloy control. To overcome these problems we utilised metal-specific non-complexing organic additives, which can significantly slow down or completely inhibit deposition of the alloying element in a certain range of potentials. In this paper, we present the recent developments for SnBi and SnCu plating chemistries. The plating electrochemistry and materials properties of deposited alloys are discussed.

Solder electroplating bath including brighteners having reduced volatility

Abstract: In accordance with the invention, the volatility of a solder plating bath with volatile brighteners such as aldehydes has its volatility reduced by the addition of diols to the bath The diols to the bath The diols are advantageously 1,3 propanediol or 1,2 propanediol and are accompanied by lower molecular weight alcohols In a preferred embodiment, a diol along with low alcohol is added to a bath comprising sulfonic acid, surfactant, grain refiner and brightening agents comprising an aromatic aldehyde and a carboxylic acid

Metallic product coated on surface with doped tin or tin alloy

Abstract: PROBLEM TO BE SOLVED: To prevent production of whiskers on tin coated metallic products. SOLUTION: A metallic substrate is coated with a tin or tin alloy layer subjected to surface doping in order to suppress the growth of tin whiskers. A metallic ground surface layer is arbitrarily selectively arranged between the substrate and the tin. In an exemplary embodiment, the metallic substrate contains the nickel surface layer and the copper alloy formed by coating gold or palladium with the tin layer subjected to surface doping. The doping suppresses the growth of the whiskers and eventually the structure is particularly effective as an electrical connector or a lead frame.

Electroplating palladium alloy composition and electroplating method using the composition

Abstract: PROBLEM TO BE SOLVED: To provide an aqueous electroplating bath for electroplating of a palladium alloy in a mixed ligand system. SOLUTION: The first ligand forms a complex of palladium and the second ligand forms a complex of another metal, functioning to make the plating potentials of the two metals to proximate values. The palladium and the alloy metals exist as the complexes in different structures.

Metal article with multilayer coating

Abstract: In accordance with the invention, a metal substrate (10) is coated with a multilayer finish (11) comprising a layer (13) of tin or tin alloy and one or more outer metal layers (14). An optional metal underlayer (12) may be disposed between the substrate and the tin (13). In an exemplary embodiment the metal substrate comprises copper alloy coated with a nickel underlayer, a layer of tin and an outer metal layer of palladium. The resulting structure is particularly useful as an electrical connector or lead frame.