NAND 快閃記憶體在少量寫入/抹除操作下異常的次臨界擺幅及轉導回復

Abstract

本篇論文主要研究不同NO氮化濃度下NAND快閃記憶體元件抹寫週期的忍耐度(endurance)。採用三維元件模擬，來驗證量測特性。我們發現週期忍耐度後臨限電壓位移，轉導(Gm)回復 和次臨界擺幅 (SS) 上升等現象發生。本論文主要討論一種模型，淺溝槽絕緣(STI)內的正電荷及穿隧氧化層邊緣(edge of the tunnel oxide)的正電荷為最可能週期忍耐度後發生退化的主要原因。

In this thesis, we investigate endurance characteristic for 100 cycles with different NO nitridation in NAND FLASH memory device. After endurance, the Vt shift, Gm recovery and subthreshold swing (SS) degradation occurred. So, in this work, one possible model of degradation is investigated by examining the measurement data and found that the positive fixed charge in STI and in the edge of the tunnel oxide are the most reasonable to affect these degradations.