Title of Document: PROGNOSTICS OF SOLDER JOINT RELIABILITY UNDER VIBRATION LOADING USING PHYSICS OF FAILURE APPROACH Jie Gu, Doctor of Philosophy (Ph.D.), 2009 Directed By: Chair Professor and Director, Michael G. Pecht, Department of Mechanical Engineering Physics-of-failure (PoF) is an approach that utilizes knowledge of a product’s life cycle loading and failure mechanisms to perform reliabi...

This work aims to understand the reliability of Sn-Ag-Cu solder interconnects used in plastic ball grid array (PBGA) packages using microstructure evolution, laser moiré interferometry and finite-element modeling. A particle coarsening based microstructure evolution of the solder joint material during thermal excursions was studied for extended periods of time lasting for several months. The mi...

Fujitsu has implemented a company-wide effort to progressively reduce the use of lead (Pb) and eventually eliminate this environmental pollutant from its products. As part of this effort, we have developed a new lead-free solder that consists of tin (Sn), zinc (Zn), and aluminum (Al) and yet offers superior productivity and joint reliability. The new lead-free solder has a melting point equival...

Jet Propulsion Laboratory California Institute of Technology Pasadena, CA 91109 Differential expansion induced fatigue resulting from temperature cycling is a leading cause of solder joint failures in spacecraft. Achieving high reliability flight hardware requires that each element of the fatigue issue be addressed carefully. This includes defining the complete thermal-cycle environment to be e...

While the situation varies from country to country, nearly one year after the EU RoHS Directive came into force implementation of lead-free solder is progressing steadily. For lead-free soldering to be considered successful it is not sufficient just to have dealt with the challenges of mass production. It is also necessary to establish that the soldered joints produced are at least as reliable ...

Experimental research on the Pb phase coarsening of eutectic Pb/Sn flip chip solder joint under current stressing is reported. Phase growth is observed under different current densities and temperatures. Higher current density leads to faster grain coarsening. Based on the test results, a grain coarsening equation including the influence of current density is proposed, dn dn 0 1⁄4 Kjmt. The cur...