Leakage Current Reduction Mechanism of Oxide–Nitride–Oxide Inter-Poly Dielectrics through the Post Plasma Oxidation Treatment

Abstract

High quality oxide–nitride–oxide (ONO) inter-poly dielectrics were successfully fabricated by the optimized plasma oxidation without H2. The bottom low pressure chemical vapor deposition (LPCVD) oxides treated by the conventional N2O annealing step were subjected to the post deposition process using a plasma treatment. This process reduces both the leakage current and the stress-induced leakage current (SILC), while no thickness increase of the bottom LPCVD oxides was observed due to the plasma treatment. Based on the photo electron injection technique, it is found that the O2 plasma oxidation method significantly reduces the defect centers located at 1.67 nm away from the bottom oxide/floating gate interface.