A modified scheme to tune the Schottky Barrier Height of NiSi by means of dopant segregation technique

Abstract A modified scheme to tune the Schottky Barrier Height (SBH) of NiSi effectively by means of dopant segregation (DS) technique is presented. This scheme consists of the following steps: (1) The deposited Ni films undergo a rapid thermal anneal (RTA1) at 300 °C/60 s to form Ni-rich silicide followed by removal of un-reacted Ni; (2) implant boron (B) or arsenic (As) into pre-formed Ni-rich silicide and RTA2 at 450–700 °C/30 s to transform Ni-rich silicide to NiSi and to induce DS at NiSi/Si interface as well. The SBHs to electrons ( ϕ bn ) or to holes ( ϕ bp ) of NiSi tuned using this scheme by B or As DS is ≥1.0 eV, corresponding to ϕ bp or ϕ bn ≤0.1 eV, comparable to those tuned using conventional scheme by DS, in which B or As ions are implanted into NiSi followed by drive-in anneals to induce DS at NiSi/Si interface.