| Title |
Premature Failure Associated with Microstructural Coarsening in Surface Mount Solders During Thermal cycling |
| Abstract |
The growth of fatigue cracks was investigated in near-eutectic solder joints of ceramic leadless chip carriers (LLCC`s) packages subjected to thermal displacement-induced fatigue at temperature ranges of from -35℃ to 125℃ with 1hr to 4hr time period. Under these conditions, it was observed that the coarsened region of the eutectic phases developed at 45℃ to the printed circuit board during the early stage of cyclic loading. It was discussed that microstructural coarsening could lead to premature transgranular failure, which propagated up from beneath the LLCC into the fillet, resulting in deteriorated reliability of electronic systems. |