Electric-field and temperature dependence of the activation energy associated with gate induced drain leakage

We examined the effect of temperature and electric field on the activation energy (E-a) of gate-induced drain leakage (GIDL) of a MOSFET. The measured GIDL current shows a temperature dependence consistent with a non-tunneling mechanism. In the low-electric-field regime and for temperatures above 55 degrees C, E-a is about 0.4 eV and drops from 0.4 eV to 0.1 eV as the applied gate voltage goes below V-FB in the accumulation direction (decreased for the n-channel MOSFET). This suggests that electron-hole-pair generation at Si/SiO2 interface traps (D-it), enhanced by the electric field (the Poole-Frenkel effect), dominates GIDL in that regime. For temperatures below 55 degrees C, E-a is less than 0.15 eV for both weak and strong electric fields and displays minimal temperature dependence, indicating inelastic trap-assisted tunneling or phonon-assisted tunneling from a trap. In the very strong-electric-field regime (> 1 MV/cm), band-to-band tunneling is the dominant mechanism. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4789382]