Solution Aging Impact on the Voiding in Cu-Solder Joints

A completely electrochemical scheme has been proposed for synthesis of nanoporous Au (NPG) based catalyst for formic acid oxidation. The protocol realized on Au and glassy carbon includes first, electrochemical co-deposition of a Au(1-x)Agx alloy, followed by de-alloying (Ag dissolution) that generates an ultrathin and continuous porous structure of thickness less than 20 nm. The NPG is then functionalized with Pt by surface limited redox replacement of underpotentially deposited Pb layer to form Pt-NPG. Testing of the catalyst shows its high activity toward formic acid oxidation.

A comprehensive study of the effect of poly(ethylene glycol) (PEG) degradation on the void formation at the interface of electroplated Cu and Pb-free solder has been performed. Chemical analysis at different times of the deposition process by MALDI-TOF reveals a dramatic shift in the peaks to lower mass range with aging. SEM cross-sectional images of Cu-solder interface show a decrease in void formation attributed to PEG degradation with aging. This effect is confirmed quantitatively by the use of plating solutions containing PEG with preselected molecular weight.

All Electrochemical Pt Nanoporous Catalyst Synthesis

Thin NP filmdeposited on Au

Clustered NP catalystdeposited on glassy carbon

Alloy Electrodeposition

De-alloying Pt Functionalization

Formic Acid Oxidation

Development and Application of a New Method for Epitaxial Growth of Metals, Alloys and Multilayers by Surface Limited Redox Replacement

Nikolay Dimitrov, SUNY at Binghamton, DMR 0742016

Dissemination: A large portion of the activities on development of protocols for synthesis of catalysts based on nanoporous metals and their functionalization supported by this grant, was presented as oral talks by Nikolay Dimitrov and Martha Kamundi at the 220th Meeting of ECS and Fall Meeting of MRS, both in Boston MA. Matt Fayette introduced the audience of GRC in Electrodeposition to the essence of PI’s group activities. Two related papers were published in ACS Advanced Materials & Interfaces and Journal of Electronic Materials and two more are in preparation.

Professional Development

Fred Wafula graduated with Ph.D. in December of 2012 and found and industrial postdoctoral position.

Matt Fayette presented an invited talk to the audience of his Alma Mater, SUNY at Potsdam, Potsdam NY.

During the summer of 2012 Rohan Gheewala was involved in a REU work with our research group.

Ongoing Collaborations

Studies of the durability of Pt-coated catalysts for formic acid oxidation have been carried out in collaboration with Dr. Natasa Vasiljevic from University of Bristol, UK.

Work on the catalytic activity of Pt4Cu(hkl) alloy nanoparticles and thin films with Dr. Fang’s group has been finalized and a paper is in preparation.

Glass interposers metalized with combined electroless/ electrolytic protocol continues in collaboration with Dr. Borgesen’s group at SUNY Binghamton.

Dr. Natasa VasiljevicDepartment of Physics,University of Bristol, UK

Rohan Gheewala, a sophomore student pursuing business major and minor in engineering joined in May 2012 the PI’s group for a ten-week summer REU activity sponsored by NSF. He participated in our Glass Interposers related research and received training on most of our Lab practices .

Dr. Peter Borgesen

ECS Boston: Pt deposition via Surface Limited Redox Replacement (SLRR) of Pb and H UPD.

DEPARTMENT OF SYSTEMS SCIENCE AND INDUSTRIAL ENGINEERING

Nikolay Dimitrov - Invited Talks:

Fred Wafula, a graduate student in the PI’s group, defended his dissertation and received his Ph.D. degree in December 2011. He is currently appointed as postdoc with Atotech, Albany, NY. His work is on Cu electroplating for electronics.

Hofstra University: All Electrochemical Fabrication of a Pt-Nanoporous Au Catalyst for Formic Acid Oxidation.

Matt Fayette, a graduate student in the PI’s group, was among the key student participants in both, 2012 Gordon Research Conference and Student Seminar. He successfully presented oral talks on both events and received colleagues’ acclamation.

Martha Kamundi, a graduate student in the PI’s group, gave an oral presentation in the main program of 2011 Fall Meeting of Materials Research Society in Boston. The talk covered the mainstream of her Ph.D. dissertation due by the end of 2012.

Development and Application of a New Method for Epitaxial Growth of Metals, Alloys and Multilayers by Surface Limited Redox Replacement

Nikolay Dimitrov, SUNY at Binghamton, DMR 0742016