In-situ synchrotron micro-diffraction study of surface, interface, grain structure, and strain/stress evolution during Sn whisker/hillock formation

Journal Article · Mon Mar 14 00:00:00 EDT 2016 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4942920· OSTI ID:22596885

Pei, Fei; Bower, Allan F.; Chason, Eric ^[1]; Jadhav, Nitin ^[2]; Buchovecky, Eric ^[3]; Liu, Wenjun; Tischler, Jonathan Z.; Xu, Ruqing ^[4]; Ice, Gene E. ^[5]

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1. School of Engineering, Brown University, Providence, Rhode Island 02912 (United States)
2. IBM, Hopewell Junction, New York 12533 (United States)
3. Saint-Gobain, Northboro R&D Center, Northborough, Massachusetts 01532 (United States)
4. Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)
5. Oak Ridge National Lab, Oak Ridge, Tennessee 37831 (United States)

We have performed X-ray synchrotron micro-diffraction measurements to study the processes controlling the formation of hillocks and whiskers in Sn layers on Cu. The studies were done in real-time on Sn layers that were electro-deposited immediately before the X-ray measurements were started. This enabled a region of the sample to be monitored from the as-deposited state until after a hillock feature formed. In addition to measuring the grain orientation and deviatoric strain (via Laue diffraction), the X-ray fluorescence was monitored to quantify the evolution of the Sn surface morphology and the formation of intermetallic compound (IMC) at the Sn-Cu interface. The results capture the simultaneous growth of the feature and the corresponding film stress, grain orientation, and IMC formation. The observations are compared with proposed mechanisms for whisker/hillock growth and nucleation.

• OSTI ID: 22596885
• Journal Information: Journal of Applied Physics, Vol. 119, Issue 10; Other Information: (c) 2016 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COMPARATIVE EVALUATIONS
COPPER
DEPOSITS
DIFFRACTION
FLUORESCENCE
GRAIN ORIENTATION
INTERFACES
INTERMETALLIC COMPOUNDS
MORPHOLOGY
STRAINS
STRESSES
SURFACES
SYNCHROTRONS
TIN
WHISKERS
X RADIATION