Time-dependent dielectric breakdown of hydrogenated silicon carbon nitride thin films under the influence of copper ions

Time-dependent dielectric breakdown (TDDB) of hydrogenated silicon carbon nitride (H:SiCN) thin films deposited using a plasma-enhanced chemical vapor deposition has been studied using metal-insulator-semiconductor capacitors with Cu gate electrodes. The experimental TDDB data of these films agree excellently with the thermochemical E model where the time to breakdown decreases exponentially with an increase in the electric field and temperature. Breakdown of the H:SiCN films was found to be significantly accelerated by the presence of Cu ions in the films. The breakdown acceleration is believed to be caused by an electric field enhancement due to the accumulation of positively charged Cu ions.