Effects of tungsten silicidation on Fowler-Nordheim tunnelling current and charge trapping in polysilicon-oxide-silicon capacitors

Results of Fowler-Nordheim current stress are compared for tungsten polycided and non-polycided gate MOS capacitors. An initial high pre-tunnelling current, decreasing with subsequent gate bias scan, is reported for non-polycided device tunnelling from the gate. This is attributed to the charging of oxide electron traps. A temperature anneal at 200°C demonstrates that these traps are rechargeable