Development of 'ECOBRASS' Lead-free Copper Alloy.

Comparison of thermo-mechanical behavior of lead-free copper and tin-lead column grid array packages

Thermo-mechanical behavior of the lead (Pb)-free ceramic copper column grid array (CuCGA) package under accelerated thermal cycling is characterized and compared with the conventional tin–lead (Sn–Pb) ceramic column grid array (CCGA). In situ thermal deformations of the highest DNP (distance to neutral point) copper column is measured for an initial isothermal loading of DT = 75 C and subsequen...

A Test Methodology for Copper Dissolution in Lead-Free Alloys

Lead-free selective soldering can result in extended times at high temperatures, which in turn can result in excessive dissolution of exposed copper, such as plated through holes. This phenomenon is more severe with lead-free, since the alloys have higher melting points, hence requiring longer times for the PTH to reach the higher temperatures, and the alloys typically have a greater capacity t...

Lead-Free Wrought Copper Alloys for Bushings and Sliding Elements

Initial Stages of Oxidation of Copper and Copper-iron Alloy

The initial oxidation stages of copper and copper-iron alloys have been studied by the AtomProbe Field Ion Microscope (AP-FIM). The depth profiles of copper oxide formed in-situ were successfully determined. The composition of the oxide was close to the value of Cu20, but a large concentration fluctuation was found. The interface between the oxide and the metal was found to be diffuse, the widt...

Lead-free and Tin-lead Rework Development Activities within the Nemi Lead-free Assembly and Rework Project

With the upcoming European ROHS legislation and other global movements to lead-free assembly, the NEMI lead-free rework group investigated and developed lead-free rework processes for medium to high-end computer products. The work concentrated on development of lead-free hot air convection rework for PBGA, CBGA, and uBGA, and lead-free hand soldering rework for TSOP and 2512 chip components on ...