A Comprehensive Understanding of the Erase of TANOS Memories Through Charge Separation Experiments and Simulations

We investigate and quantify the role played by electrons and holes during the erase operation of TANOS memories by means of charge separation experiments and physics-based simulations. Results demonstrate that electron emission via trap-to-band tunneling dominates the first part of the erase operation, whereas hole injection prevails in the remaining part of the transient. In addition, we show that the efficiency of the erase operation is high and constant mainly because of the high energy offset between nitride and alumina valence bands. Our results clearly identify the physical mechanisms responsible for TANOS erase and allow deriving some important guidelines for the optimization of this operation.

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