1/f noise interpretation of the effect of gate oxide nitridation and reoxidation in dielectric traps

Nitrided gate oxides and reoxidized nitrided gate oxides exhibit increased reliability under electrical and radiation stress and improved dopant barrier properties. However, the process of nitridation introduces oxide charges and traps. In this paper, 1/f noise measurements in MOSFETs and the carrier number fluctuation (McWhorter) model are used to extract the dielectric trap density in space and energy near the conduction and valence band edges of silicon. It is found that reoxidation can be used to reduce nitridation induced interface traps to levels found in oxides.>