Abstract
In the recently years, flash memories are becoming widely used in many applications, such as solid state disks, embedded controller, and mobile communication products. Therefore, the fault modeling of flash memories plays an important role in the testing field. The NAND-type flash memory is one of the commonly used flash memories. To explore all faulty behaviors on NAND-type flash memory is impractical, and therefore the SPICE model level simulation for defects is considered. In this thesis, two SPICE models of the flash cell are developed and used for circuit-level faulty behavior simulation. The defects can be classified to 25 types and result in 14 types of faults. For our study, resistive short defects generally cause parametric faults. We propose the faulty behavior with different order of short resistance and coupling capacitance. The results show that resistive short defects not only cause parametric faults but also cause stuck-at fault or degraded threshold voltage fault. From the proposed fault model, if only stuck-at-1 and 0 faults are considered, the fault coverage is poor. However, traditional 100% fault coverage based on stuck-at fault model is too far from real fault coverage.