In this paper the influence of the temperature cycle time history profile on the fatigue life of ball grid array (BGA) solder joints is studied. Temperature time history in a Pentium processor laptop computer was measured for a three-month period by means of thermocouples placed inside the computer. In addition, pentium BGA packages were subjected to industry standard temperature cycles and als...

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...

Evaluation of the low cycle fatigue life by the small specimen test technique (SSTT) and some other properties (metallographical structure and Vickers hardness) for the TIG (tungsten inert gas) weld of F82H IEA-heat were carried out. The TIG-weld was distinguished into seven regions with different metallographical structure and hardness, which were the base metal (BM) region (region with almost...

Life time of electronic products is often limited by competing failure mechanisms brought on by the product’s use and its surrounding environment. Solder interconnect failure is a known life limiting failure mechanism that is induced by repeated temperature excursions. Thermal fatigue reliability of solder is conventionally assessed by simple temperature cycling tests, which apply a constant te...

The coherent hadron production analogous to Cherenkov radiation of photons gives rise to the ring-like events. Being projected on the ring diameter they produce the two-bump structure recently observed for the away-side jets at RHIC. The position of the peaks and their height determine such properties of the hadronic medium as its nuclear refractive index, the parton density, the free path leng...

A novel and direct method to measure the stress-strain properties of surface mount solder joints is proposed in this paper. The specimen used in the experiments is a quad flat pack (QFP)-solder-printed circuit board (PCB) assembly and the fabrication of solder joints makes use of conventional surface mount technology (SMT). Mechanical cycling and thermal shock testing can be conducted directly ...

The reliability of solder joints in electronic packaging is becoming more important as the ball grid array (BGA) develops rapidly into the most popular packaging technology. Thermal fatigue of solder joints has been a reliability concern in the electronic packaging industry since the introduction of surface mount technology (SMT). Microstructural coarsening (phase growth) is considered to be cl...

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