Here, 130 silver pillars were fabricated using a novel embossing technique that did not pose the issues associated with focussed-ion beam milling: surface amorphization and Ga contamination. Displacement-controlled compression tests on pillars with diameters of 130 to 3000nm revealed, for sub-micrometer samples, an inverse proportionality of flow strength to diameter, which was associated with a wide strength distribution and a deformation taking place in large discrete strain bursts. The largest pillars showed instead near bulk-like behavior. Unlike studies on other face-centred cubic materials, mechanical twinning was also an important deformation mechanism in Ag due to its very low stacking fault energy. In addition, occasional pre-existing twin boundaries constituted preferential planes for localized deformation if favorably sloped. Despite the absence of ion-induced artefacts, scaling laws and absolute values of strength were comparable to those obtained via focussed-ion beam milling.

Deformation Behavior of Silver Submicrometer-Pillars Prepared by Nanoimprinting. S.Buzzi, M.Dietiker, K.Kunze, R.Spolenak, J.F.Löffler: Philosophical Magazine, 2009, 89[10], 869-84