標題: | Thermomigration of Cu-Sn and Ni-Sn intermetallic compounds during electromigration in Pb-free SnAg solder joints |
作者: | Chen, Hsiao-Yun Chen, Chih 材料科學與工程學系 Department of Materials Science and Engineering |
公開日期: | 1-四月-2011 |
摘要: | Thermomigration in Pb-free SnAg solder alloys is investigated during accelerated electromigration tests under 9.7 x 10(3) A/cm(2) at 150 degrees C. It is found that Cu-Sn intermetallic compounds (IMCs) migrate toward the cold end on the substrate side and, as a result, voids accumulate in the chip side for the bump with current flowing from the substrate end to the chip end. Theoretical calculations indicate that the thermomigration force is greater than the electromigration force at a thermal gradient above 400 degrees C/cm for this stressing condition. Copper atoms may migrate against current flow and become the dominant diffusion species. On the other hand, Ni-Sn IMCs did not migrate even under a huge thermal gradient of 1400 degrees C/cm. These findings provide more understanding on the thermomigration of metallization materials in flip-chip solder joints. |
URI: | http://dx.doi.org/10.1557/jmr.2011.25 http://hdl.handle.net/11536/9019 |
ISSN: | 0884-2914 |
DOI: | 10.1557/jmr.2011.25 |
期刊: | JOURNAL OF MATERIALS RESEARCH |
Volume: | 26 |
Issue: | 8 |
起始頁: | 983 |
結束頁: | 991 |
顯示於類別: | 期刊論文 |