Characterization and modeling of program/erase induced device degradation in 2T-FNFN-NOR flash memories

In this paper, we report the program/erase degradation mechanisms in two transistor (2T) Fowler-Nordheim (FN) tunneling operated flash memories, based on extensive experimental study of the degradation characteristics of such 2T-FNFN test memory arrays and reference transistor arrays from several generation process technologies. A quantitative model has been established describing the degradation characteristics under various stress conditions (i.e. degradation due to program/erase cycling at various voltages and temperatures). A software tool has been developed to estimate the reliability performance of various products under different use conditions. This model (and tool) can also be used to estimate the product reliability performance in future process generations.