Abram R, Chrobak D, Nowak R
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.
Phys Rev Lett. 2017 Mar 3;118(9):095502. doi: 10.1103/PhysRevLett.118.095502.
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.
这封信涉及使用原子模拟对硅晶体表面纳米变形的研究。我们的结果解释了纳米压痕过程中突然弹出事件的出现和不出现情况。基于载荷-深度响应、应力诱导的晶体结构演变和表面轮廓，我们确定了导致压痕变形的两个不同过程。第一个过程导致突然弹出，是由晶体高压Si-III/XII相的挤出组成，而第二个过程没有突然弹出，依赖于非晶化硅向晶体表面的流动。硅技术特别感兴趣的将是我们对非晶化、晶体到晶体转变以及转变材料向表面挤出之间相互作用的阐明。
