Modulation of effective Schottky barrier height of nickel silicide on silicon using pre-silicide ammonium sulfide treatment

Abstract

Modulation of effective electron Schottky Barrier Height (ΦBn,eff) by sulfur (S) donor-like traps was achieved through the use of pre-silicide ammonium sulfide treatment. The mechanisms responsible for the reduction of ΦBn,eff were elucidated through an analysis of current-voltage measurements taken at various temperatures. Owing to the different physical locations of the S donor-like traps near the metal/semiconductor junction, e.g., at the interface and in the depletion region, mechanisms such as trap-assisted tunneling (TAT) and generation of electron-hole pairs can participate in the carrier transport, and be more dominant in the low temperature regime for reducing ΦBn,eff.