Atomistic structural change of silicon surface under a nanoparticle collision

As the dimensions of the semiconductor device com-ponents shrink, a profound understanding of the mi-cro/nanomachining of monocrystalline silicon surface isbecoming essential. Molecular dynamics (MD) simulationis a powerful tool for the study of the processing mecha-nism of silicon surfaces. The MD simulations of nano-cutting1,2], nano-grinding3,4], as well as nano-indenta-tion5,6] have been studied intensively. It is shown that theamorphous phase transformation and the plastic flow in-si…

Atomistic structural change of silicon surface under a nanoparticle collision

This study investigates the effect of the incident angle on the trajectory of a nanoparticle and the damaged region on a silicon surface, by molecular dynamic simulation of the collision and recoil of a nanoparticle with a monocrystlline silicon surface. With the change of the incident angle, the recoil angle of the particle changes in a large range from an obtuse angle to an acute angle. The incident angle determines which part of the particle is in contact with the surface when the particle penetrates into the deepest position. Furthermore, it is the contacting part of the particle that the released elastic deformation energy of the surface acts on. These lead to the phenomenon that the recoil angle is sensitive to the incident angle in the collision process at a nanoseale. A depressed region is formed on the surface after the collision. The shape of the damaged region changes from a deep scoop to a flat arc, which is consistent with the trajectory of the particle. Some silicon atoms on the surface are extruded out by the incident particle, and form a pileup at the rim of the depressed region.