Evaluation of the degradation of floating-gate memories with Al2O3 tunnel oxide

Replacing the tunnel oxide of non-volatile memories by a high-k dielectric is addressed in this paper. This work reports in its first part an experimental study of conduction and trapping in Al
₂
O
₃
layers. The experimental data of these layers is then integrated in a novel endurance model suitable for flash memories with high-k tunnel oxide. Simulation results show that low (+8/-7V) operating voltages can be used to obtain large threshold voltage shifts, and despite a great amount of trapped negative charges (several 10
₁₂
/cm
²
), the programming window isn't closed after 10
⁷
write/erase (W/E) cycles