High quality oxynitride gate dielectrics preparedby reoxidation ofNH 3 -nitrided SiO 2 in N 2 O ambient

The significant advantages of reoxidation of NH3-nitrided SiO2 using N2O, as opposed to O2, in a rapid thermal system have been demonstrated. MOS capacitors with N2O-reoxidised NH3-nitrided SiO2 show improved charge-to-breakdown characteristics and suppressed interface state generation under both injection polarities compared to those with pure SiO2 and O2-reoxidised NH3-nitrided SiO2. Significant reduction of nitridation-induced traps by N2O reoxidation is mainly responsible for these improvements.