title: Origin of a Nanoindentation Pop-in Event in Silicon Crystal.
abstract: The Letter concerns surface nanodeformation of Si crystal using atomistic simulation. Our results account for both the occurrence and absence of pop-in events during nanoindentation. We have identified two distinct processes responsible for indentation deformation based on load-depth response, stress-induced evolution of crystalline structure and surface profile. The first, resulting in a pop-in, consists of the extrusion of the crystalline high pressure Si-III/XII phase, while the second, without a pop-in, relies on a flow of amorphized Si to the crystal surface. Of particular interest to silicon technology will be our clarification of the interplay among amorphization, crystal-to-crystal transition, and extrusion of transformed material to the surface.
authors.affiliation: Nordic Hysitron Laboratory, Department of Chemistry and Materials Science, School of Chemical Engineering, Aalto University, 00076 Aalto, Finland.
authors.forename: R
authors.initials: R
authors.lastname: Abram
authors.affiliation: Nordic Hysitron Laboratory, Department of Chemistry and Materials Science, School of Chemical Engineering, Aalto University, 00076 Aalto, Finland.|Institute of Materials Science, University of Silesia in Katowice, 75 Pulku Piechoty 1A, 41-500 Chorzow, Poland.
authors.forename: D
authors.initials: D
authors.lastname: Chrobak
authors.affiliation: Nordic Hysitron Laboratory, Department of Chemistry and Materials Science, School of Chemical Engineering, Aalto University, 00076 Aalto, Finland.|Extreme Energy-Density Research Institute, Nagaoka University of Technology, Kamitomioka 1603-1, Nagaoka, Niigata 940-2188, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Nowak