Geometrically Amplified Wetting of Silver Nanosolder on a Rough Diamond Surface.

Abstract

The wetting behavior of silver at the nanoscale on a textured diamond substrate is not absolutely roughness-dependent in printing diamond chips, tough bioimplant coating, and joining for cutting tool industries. This study uses a molecular dynamics simulation to capture the stochastic wetting behavior toward precision for given geometries. It is deduced that the metalophilic character of molten silver is increased with an increase in roughness on sinusoidal contoured diamond substrates rather than orthogonal pillars of the same roughness until an equilibration time of 210 ps at a temperature of 950 K. Increasing the roughness after the equilibrium time causes a supermetalophilic angle of 13° for the sinusoid at 500 ps, and the orthogonal design causes the Wenzel state. Therefore, wetting states are metastable and ultimately depend upon the wetting time and geometry rather than the roughness only. A high joining strength creates a long-lasting coating, owing to the high surface energy of the textured surface. This study presents effective thin seam development in the least possible time of 230 ps and silver consumption at the nanoscale for supermetalophilic and metalophobic coatings in electronic packaging.