Synchrotron radiation based X-ray micro-diffraction study on reliability issues of solder joints in electronic packaging technology

Orientation distribution of Cu⁶Sn⁵ and its relationship with orientation of substrate Cu was studied with synchrotron based micro X-ray diffraction. We have obtained Laue spots both from Cu⁶Sn⁵ and Cu at the same time. From the Laue pattern, orientation distribution maps of Cu⁶Sn⁵ and Cu were obtained. Orientations Cu⁶Sn⁵ scallops had strong dependence to that of Cu. [001] direction of Cu⁶Sn⁵ was always parallel to [110] of Cu, to minimize misfit. It was also found that there are loses in its texture as reflow time increases