High quality, ultrathin nitrided gate dielectric films were investigated to study their effects on device performance and reliability for ultralarge scale integration complementary metal oxide semiconductor applications. Thermal nitridation was performed on 200 mm wafers in a vertical reduced pressure furnace using N2O and/or NH3. It was demonstrated that nitrided gate dielectric films (ROXNOX, N2O oxide) have improved hot carrier lifetime and barrier properties to boron diffusion. In addition, N2O oxides, as well as ROXNOX, were found to be a promising alternative gate dielectric to the conventional oxide.