The package to board interconnection shear strength (PBISS) test method yields an amalgamated measure of pad peel strength, solder/pad interfacial strength and bulk solder shear strength. This measure mirrors the reliability of the actual product better than any single component strength value. Using a novel fixture that ensures pure shear stresses on the package, the shear strengths of two different ball grid array packages with Sn62PbAg2 solder balls are characterized as a function of pad finish and board build-up layer type. The tests can be performed relatively quickly (< 15 minutes for an entire package on board) with good repeatability. Results indicate that the component shear test is sensitive to the variables studied and attractive as a candidate technique for quantifying solder joint quality and integrity on actual production samples for a variety of package types and sizes. Potential applications of this method are for materials/process/vendor evaluation during product development phase and as a production/supplier quality assessment tool in the factory. Key words: interconnection strength, shear test, area array package, solder joint, pad surface finish

This paper reports the observations of the grain-refining mechanism found in Al-0.5Cu thin films that are subjected to hydrostatic compressive pressure during the annealing process. The films are deposited on Si substrates and subsequently placed under 60 MPa Ar gas pressure at 400°C. Transmission electron microscopy on these films reveals that plastic deformation occurs by dislocation slip and induces a refined grain structure. Polygonization is the primary mechanism for grain refining, resulting in the formation of sub-grain boundaries.