Trap-assisted tunneling current through ultra-thin oxide

The increase of gate current in a MOS device following high field stressing is referred to as stress-induced leakage current (SILC) and is widely believed to result from trap-assisted tunneling (TAT). Based on a consideration of the relative magnitudes of the direct and trap-assisted tunneling probabilities, this work explains why SILC is observed only within a "window" of oxide thickness. This work also provides further experimental evidence that SILC is due to inelastic trap-assisted tunneling of electrons from the cathode conduction band.