Stress-induced leakage current in lightly Al-doped Ta2O5

The response of lightly Al-doped Ta₂O₅ stacked films (6 nm) to constant current stress (CCS) under gate injection (current stress in the range of 1 to 30 mA/cm² and stressing time of 50-400 s) has been investigated. Different degradation mechanisms control the stress-induced leakage current (SILC) in dependence on both the stress conditions and the applied measurement voltage. The well known charge trapping in pre-existing traps operates only at low level stress. The new trap generation plays a key role in the current degradation and is the dominant mechanism controlling the SILC.