Novel submicron MOS devices by self-aligned nitridation of silicide (Sanicide)

A new MOS technology with the following advantages has been investigated: TiSi
2
is formed by being self-aligned to source and drain regions by silicidation; and TiN is formed by self-aligned to contact regions by direct nitridation. TiSi
2
was prepared by two-step annealing to only form silicide on the diffused layers. TiN was formed by direct nitridation of TiSi
2
in N
2
at a temperature higher than 900 °C. The TiN formed using this method was found to be an effective diffusion barrier between Al and Si for annealing at up to 500 °C for 1 hour. PSG-cap annealing provided excellent p-n junction characteristics with a silicide layer of 4 Ω/□ even after annealing at 950 °C for 30 min. Characteristics of devices fabricated by this new technology were demonstrated.