MODELING THE MEMORY RETENTION CHARACTERISTICS OF SILICON-NITRIDE-OXIDE-SILICON NONVOLATILE TRANSISTORS IN A VARYING THERMAL ENVIRONMENT

The memory retention characteristics of silicon-nitride-oxide-silicon nonvolatile memory devices are found to be strongly thermally activated. A model is developed based on thermal emission of charge from traps. This model accurately predicts the threshold voltage decay of transistors stored in varying thermal environments. The model is demonstrated to be accurate over 7 decades of time and for temperatures between -40 and 200 °C.