Low temperature (850 degrees C) two-step N2O annealed thin gate oxides

Abstract

The electrical characteristics of thin gate dielectrics prepared by low temperature (850 degrees C) two-step N2O nitridation (LTN) process are presented. The gate oxides were grown by wet oxidation at 800 degrees C and then annealed in N2O at 850 degrees C. The oxide with N2O anneal, even for low temperature (850 degrees C), had nitrogen incorporation at oxide/silicon interface. The charge trapping phenomena and interface-state generation (Delta D-itm) induced by constant current stressing were reduced and charge-to-breakdown (Q(bd)) under constant current stressing was increased. This LTN oxynitride was used as gate dielectric for N-channel MOSFET, whose hot-carrier immunity was shown improved and reverse short channel effect (RSCE) was suppressed.