Background: The total dose effect studies for the Silicon-Oxide-Nitride-Oxide-Silicon (SONOS) have not been mainly focused on fail mechanism in circuit. Purpose: A commercial SONOS-based Nitride-Read-Only- Memory (NROM) was irradiated by 60Co γ rays and annealed

Total Ionizing Dose (TID) failure mechanism and annealing characteristics of the device were analyzed. Methods: DC

AC and function parameters of this memory were tested in radiation and annealing by VLSI test system

the radiation-sensitive parameters were obtained through analyzing the test data

and the reason for function failure was analyzed. Results: The study showed that: the threshold of MOS in charge pump and the sense amplifier were drift because of the interface trap charge

and the circuit module performance deterioration led to functional failure of the device. The current parameters were raised rapidly because leakage paths formed in Shallow Trench Isolation (STI). Conclusion: A little of interface trap charge was annealed during annealing

resulting in incomplete recovery of circuit module performance

and insignificant drop of the current parameters.Cited