Electromigration damage characterization in Sn-3.9Ag-0.7Cu and Sn-3.9Ag-0.7Cu-0.5Ce solder joints by three-dimensional X-ray tomography and scanning electron microscopy

H. X. Xie, D. Friedman, K. Mirpuri, Nikhilesh Chawla

Research output: Contribution to journalArticle

32 Scopus citations

Abstract

Cerium (Ce)-containing Sn-3.9Ag-0.7Cu alloy exhibits desirable attributes of microstructural refinement, increased ductility, and mechanical shock performance, while possessing better oxidation resistance than other rare-earth-containing solders. In addition to the beneficial mechanical properties, it is imperative to study the reliability performance of novel solder alloys in the form of electromigration experiments, in comparison with Sn-3.9Ag-0.7Cu. In this study, electromigration tests were conducted on solder joints at elevated temperature with a constant current using a V-groove testing methodology. The microstructural change of solder joints during electromigration was investigated by scanning electron microscopy, and the void growth was monitored utilizing the three-dimensional (3D) x-ray microtomography imaging technique. The current density inside the solder matrix was determined by 3D microstructure-based finite-element modeling. Finally, the product of diffusivity and effective charge number of solder joints during electromigration was calculated from both marker displacement and 3D void growth. It was found that electromigration-induced Cu diffusion in Sn-3.9Ag-0.7Cu-0.5Ce alloy was greatly accelerated, and void formation at the cathode side was retarded as a result of finer microstructure and existence of CeSn3 intermetallic particles.

Original languageEnglish (US)
Pages (from-to)33-42
Number of pages10
JournalJournal of Electronic Materials
Volume43
Issue number1
DOIs
StatePublished - Jan 1 2014

Keywords

  • Rare earth
  • cerium
  • electromigration
  • lead-free solder
  • x-ray tomography

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Electrical and Electronic Engineering
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Electromigration damage characterization in Sn-3.9Ag-0.7Cu and Sn-3.9Ag-0.7Cu-0.5Ce solder joints by three-dimensional X-ray tomography and scanning electron microscopy'. Together they form a unique fingerprint.

  • Cite this