Plasma Anodic Nitridation of Silicon in N 2 ‐ H 2 System

Silicon nitride films were directly formed on silicon by plasma anodic nitridation within nitrogen and hydrogen. The nitridation pressure ranged from 0.5 to 2.0 torr, at temperatures from 700° to 900°C. The growth rate of silicon nitride increased with an increase of the dc bias voltage to the silicon wafers. The refractive index of the films was measured to be about 2.00–2.30 by ellipsometry. Film composition was analyzed with Auger electron spectroscopy. Dielectric breakdown strength of the silicon nitride films was about 6.0 MV/cm after oxygen heat‐treatment.