An investigation of annealing effect on forming nickel disilicide by ion beam synthesis

Abstract

In this study, we investigated the annealing effects of forming the nickel disilicide by ion beam synthesis. An MEVVA (metal vapor vacuum arc) ion implanter implanted nickel ions into silicon wafers at an elevated temperature of 100°C. The as-implanted specimens were furnace annealed in an argon ambient under various temperatures for 30min and various times at 550°C. The results show that the poly nickel disilicide was found in the as-implanted specimen with an ion fluence of 1×1017ions/cm2. The sheet resistance and the Si/Ni ratio of the specimens were affected by the distribution of nickel atoms and the formation of nickel disilicide. The minimum sheet resistance and the Si/Ni ratio were obtained at the post-annealing temperature of 550°C for 30min. Additionally, the rectangular precipitates were elongated along the surface of the substrate as the annealing time increased. Thus, the formation of the precipitate proved to be anisotropic.