Study of silicon surface implanted by silver ions

Abstract

Ag+-ion implantation of single-crystal c-Si at low-energy (E = 30 keV) high-doses (D = 1.25⋅1015–1.5⋅1017 ion/cm2) and current density (J = 2, 8, 15 μA/cm2) was carried out. The changes of Si surface morphology after ion implantation were studied by scanning electron and atomic force microscopy. The near surface area of samples was also analyzed by diffraction of the backscattered electrons and energy-dispersive X-ray microanalysis. At the lowest implantation doses of c-Si amorphization of near-surface layer was observed. Ag nanoparticles were synthesized and uniformly distributed over the near Si surface when the threshold dose of 3.1⋅1015 ion/cm2 is exceeded. At a dose of more than 1017 ion/cm2, the formation of a surface porous Si structure was detected. Ag nanoparticle size distribution function becomes bimodal and the largest particles were localized along Si-pore walls.