快閃記憶體目前被廣泛地應用在各種電腦、通訊、及消費性電子產品中。隨著其記憶容量的增加和應用層面的擴展，一個有效的故障模型在快閃記憶體的測試上更是扮演一個重要的角色。而一般靜╱動態隨機存取記憶體的元件結構和操作模式都和快閃記憶體有相當大的差別，所以其故障行為必定迥然不同。因此，必須要另外發展適用於快閃記憶體的故障模型。
反及閘型態快閃記憶體是快閃記憶體中常被使用的一種。在此篇論文中，我們利用反及閘型態快閃記憶體的陣列來進行故障行為分析。在論文的第三章中，我們提出記憶單元的等效電路模型，並用 HSPICE 這套電路模擬軟體來驗證並模擬快閃記憶體的行為。此等效電路模型可以模擬記憶單元在寫入和清除時的臨界電壓變化、汲極電流量、穿遂電流量、及電荷保存特性。

在論文的第四章中，利用第三章所提出的等效電路模型來進行故障行為的模擬和分析。我們考慮記憶單元陣列上可能發生的缺陷，模擬電路中的電阻性短路、開路、和位元線間的耦合效應所造成的故障行為，並歸納整理出14種故障。

由研究結果發現，只考慮固定電位故障的故障模型對於快閃記憶體是不夠的，其故障涵蓋率相當低。在此篇論文中，我們在電路層級模擬反及閘型態快閃記憶體的實際故障行為，並根據模擬結果建立出正確且實用的故障模型。

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.

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