The electromigration-induced microstructural variation at the joint interface and within the bulk of Pb-free and Pb-Sn solders is examined. The accumulation of solder alloy elements accelerates the interfacial reaction and thus the formation of interfacial intermetallic compound. The formation of intermetallic compound results in stress accumulation and enhances whisker growth within the solder. The torque induced by electron wind results in grain rotation of the solder bulk. The current stress causes the dissolution and thus supersaturation of second phase in the matrix, for example Zn in Sn of a Sn-Zn solder. Dissolution and thus recrystallization of the second phase occurs. The recrystallization behavior of the second phase has been observed for Sn-9Zn.
|Title of host publication||Electromigration in Thin Films and Electronic Devices|
|Subtitle of host publication||Materials and Reliability|
|Number of pages||14|
|Publication status||Published - 2011 Aug|
All Science Journal Classification (ASJC) codes
- Materials Science(all)