Internal Structure Refinement of Porous Sintered Silver via Electromigration

Abstract Atoms can move under high stress conditions such as temperature, mechanical pressure or electric current. Electromigration provides a driving force to move the atoms in metals conducting current usually resulting in the accumulation of atoms and void formation in anode and cathode respectively. The electromigration effect is normally considered a serious problem for electronic circuits but the recent works1–7 show that it can be used constructively for controlled fabrication of nanostructures2–4.We demonstrate that electromigration can be utilized to refine the porous structure of a sintered silver stripe leading to transformation of the internal pore and grain structure. The results show that pore shape, size and distribution are significantly changed after electromigration. Similarly, we have used the electromigration effect to mass produce nanorods under current densities of the order of 2.4 ×10+8 A/m2. Nanorods were formed across the whole stripe contrasting with studies on non-porous substra...