Effects of Bottom Polysilicon Doping on the Reliability of Interpoly Oxide Grown by Using Electron Cyclotron Resonance N2O-Plasma

Abstract

The Effects of the bottom polysilicon doping on the reliability of polyoxides grown using electron cyclotron resonance (ECR) N2O-plasma have been investigated for the interpoly dielectrics (IPDs) of nonvolatile memories (NVMs). In situ doped polysilicon films have a smooth surface. ECR N2O-plasma polyoxide on in situ doped polysilicon has a lower leakage current and a higher breakdown field, furthermore, a lower electron trapping rate and a larger charge-to-breakdown (Q(bd)) UP to 10 C/cm(2), which is comparable to the electrical properties of ONO IPD. This is mainly attributed not only to a nitrogen-rich layer with strong Si-N bonds but also to a smooth interface. We conclude that ECR N2O-plasma polyoxide on in sitar doped polysilicon is a good candidate for an interpoly dielectric of future high density NVMs.