Fabrication of conductive interconnects by Ag migration in Cu-Ag core-shell nanoparticles

Suk Jun Kim, Purdue University - Main Campus
E A. Stach, Birck Nanotechnology Center and School of Materials Engineering, Purdue University
Carol A. Handwerker, Purdue University - Main Campus

Date of this Version



Appl. Phys. Lett. 96, 144101 (2010)

This document has been peer-reviewed.



Copyright (2010) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Appl. Phys. Lett. 96, 144101 (2010) and may be found at http://dx.doi.org/10.1063/1.3364132. The following article has been submitted to/accepted by Applied Physics Letters. Copyright (2010) Suk Jun Kim, Eric A. Stach, Carol A. Handwerker. This article is distributed under a Creative Commons Attribution 3.0 Unported License.


Fabrication of conductive nanoparticle films is observed in Cu-Ag core-shell nanoparticles by fast diffusion of Ag at 220 degrees C from particle surfaces, leading to the formation of sintered necks of Ag at the initial particle-particle contacts. Transmission electron microscopy showed that the necks were pure Ag and that particle surfaces away from the contacts were nearly Ag-free. The extent of neck formation is controllable by the choice of initial Ag thickness. Analysis of the thermodynamics of the Ag-Cu system and the relative diffusivities of Ag and Cu provide criteria for fabrication of other core-shell two-phase systems by the same mechanism.


Engineering | Nanoscience and Nanotechnology