A comparison of active near-interface traps in nitrided and as-grown gate oxides by the direct measurement technique

Abstract

This paper presents a comparative analysis of the electrically active near-interface traps, energetically located above the bottom of conduction band. Two different samples of N-type SiC MOS capacitors were fabricated with gate oxides grown in (1) dry O2 (as-grown) and (2) dry O2 annealed in nitric oxide (nitride). Measurements performed by the direct measurement method revealed that the traps located further away from the SiO2/SiC interface are removed by nitridation. A spatially localized behaviour of NITs is observed only in the nitrided gate oxide but not in the as-grown gate oxide.