Advanced Features of Electrolytic Silver-tin (AgSn20) Process

This work describes the Silveron™ GT-820 Silver-Tin as a robust process for the electrodeposition of silver-tin alloys of composition equal to Ag3Sn and Ag4Sn. A design of experiment method was used to study the influence of process parameters on the deposit performance. It was found that the alloy composition is controlled by organics components of the bath. It is independent on the metal concentration ratio and the applied current density inside the specified process window. The silver-tin deposit is semi-crystalline directly after plating but can be converted to a fully crystalline material by a short annealing. This coating is not only ductile and tarnish resistant but also displays a good insertion and retention force needed for press-fit interconnections. The product was tested successfully under serial production conditions and shown to be suitable for tin and tin-lead replacement in solderless interconnections. Continue reading

Toxicity Study of a Nanoparticle Containing Passivate Layer

The authors report on the cell toxicity study of a nanoparticle containing chromium(III) passivation. The toxicity of abrasion from zinc plated and nano-passivated screws was tested with human A549 cells. As a reference system we used the abrasion from zinc plated and thick layer passivated screws. The tests showed no toxic potential of the nanoparticle-containing passivation layer, as can be seen by the normal growing behavior of the cells in presence of the abrasion. Continue reading