THERMAL ROBUSTNESS OF VFB AND EOT IN HfO,(N) P-MOS DEVICES WITH PARTIALLY SILICIDED Pt GATE ELECTRODES

摘要

We investigated the process window of partially silicided (PASI) Pt gate electrodes which can effectively suppress unintentional threshold voltage increases of Hf-based high-k p-MOSFETs, and the impact of application of the PASI Pt (PASI-PtSi) gate electrode on their electrical properties. The values of the EOT, flat-band voltage, and the gate leakage current density of the HfO_x(N) p-MOS capacitors with the PASI-PtSi gate electrodes are almost identical when the Pt film is more than double the thickness of the poly-Si films at silicidation temperatures from 400 to 600°C. No degradation in the gate leakage current density of the HfO_x(N) MOS capacitors with the PASI-PtSi gate electrodes was observed, compared with the FUSI-NiSi and FUSI-PtSi gate electrodes. Consequently, it is concluded that the PASI technology is useful in scaled CMOS devices with Hf-based high-k dielectrics.