放射光X線ラミノグラフィによる繰返し通電を受ける電子基板におけるダイアタッチ接合部の非破壊観察

抄録

In this study, a synchrotron radiation X-ray laminography of thermal fatigue crack propagation process was investigated at die-attached joints subjected to cyclic energization loading, which is close to actual use conditions of electronic devices. Three types of thermal cycle tests with different test conditions were carried out. In order to evaluate the crack propagation quantitatively, we measured the cross sectional areas of cracks and voids in the layers. In the specimens loaded by cyclic energization of resistances, the cross-sectional area of the cracks and voids increased as the number of cycles increased. As a result, it was observed clearly and evaluated quantitatively that thermal fatigue cracks were propagated in the solder layers. In addition, the influence of creep due to the difference test conditions was clarified by calculating the crack growth rate. However, any crack propagations could not be observed in the specimen loaded by the thermal shock test.