Suppression of boron penetration in P⁺-Poly-SiGe Gate P-channel metal-oxide-semiconductor field-effect transistor using NH₃-Nitrided and N₂O-grown gate oxides

High-performance p⁺-poly-SiGe-gate p-channel metal-oxide-semiconductor field-effect transistors (pMOSFETs) have been fabricated using NH₃-nitrided or N₂O-grown oxide instead of the conventional O₂-grown oxide. It is found that NH ₃-nitrided or N₂O-grown oxide can suppress boron penetration in the p⁺-poly-SiGe gate, which improves the integrity of gate dielectrics, resulting in a low flat-band voltage shift, subthreshold swing, and drain-induced barrier lowering.