High-fluence Co implantation in Si, SiO2/Si and Si3N4/Si Part III:: heavy-fluence Co bombardment induced surface topography development

The surface topography development of Si(1 0 0), Si(1 1 1), oxide/Si and nitride/Si structures under high normal fluence (1 x 10(16)-2.6 x 10(18) ions cm(-2)) keV Co metal vapour vacuum are (MEVVA) irradiation has been investigated by scanning electron microscopy (SEM). The results show that for normal fluences up to similar to 10(17) ions cm(-2), the surface topography remains flat. As the fluence increases, pores develop and grow to form a columnar structure. At even higher fluences the columns are eroded to form an acicular structure. Deposition of a silicon dioxide or nitride layer on the Si surface leads to a significant suppression of the onset fluence for the formation of a rough surface. The porous surface could not be transformed to the network of acicular structures or a flat surface by high temperature annealing. (C) 1999 Elsevier Science B.V. All rights reserved.