臺灣博碩士論文加值系統

摘 要
由於快閃記憶體的讀寫均是藉由熱載子傳輸來達到電荷儲存和抹去的目的。因此在執行這些動作的同時，就非常有可能對於浮動閘極氧化層以及界面產生局部性的損害。而這些損害會使得記憶體元件電特性下降，並對於可靠度產生嚴重影響。因此為了能夠深入了解記憶體損害的程度以及局部熱載子對元件的影響。我們根據電荷汲引量測發展出一套直接萃取氧化層電荷和界面陷阱側向分佈的技術。由於此技術可直接從量測到的電荷汲引曲線獲得所要結果，並不需要繁雜的數值模擬。已然成為研究熱載子損傷最好的量測工具之一。 雖然
此方法在理論上好像相當容易，但是在實際上卻有一個相當難克服且不容易執行的步驟（氧化層電荷中和的步驟）。也由於此步驟並不容易執行且確定，常常使得所求得的Not和Nit分佈帶著相當程度的誤差，使之實驗失去了應有的準確性。為了要去改善此方法所造成的缺失，在本論文中我們提供了二種針對中和步驟改善的方法，其一為二階段中和步驟，其二為電荷汲引曲線數值修正。而這些改善的方法對於提升電荷汲引量測技術的準確性有著相當程度的助益。在本研究的最後，我們選取了8051微控制器（Micro-controller）和SRAM 靜態隨機存取記憶體來進行輻射總劑量測試以及低劑量效應測試，用以作為太空元件抗輻射影響評估可靠性的指標。

目 錄
摘要 ………………………………………………………………………………… i
致謝 ………………………………………………………………….…………….. ii
目錄 ..……………………………………………………………………………… iii
圖目錄 …………………………………………………………………………….. vi
第一章 緒論 ……………………………………………………….…………….. 1
1.1緒言 …………………………………………………………………. 1
1.2研究概要 ……………………………………………………………. 2
第二章 快閃式記憶體的工作原理與可靠性 …...……………………………….. 4
2.1 記憶體的介紹與回顧 ……………………………………………… 5
2.2快閃式記憶體的基本工作原理 ……………………………………. 6
2.3載子在絕緣體的傳輸機制 …………………………………………. 7
2.3.1氧化層的Fowler-Nordheim (FN) 穿遂 ……………………. 8
2.3.2通道熱電子注入 ……………...……………………………...10
( Channel-Hot-Electron (CHE) injection )
2.3.3矽基底熱電子注入 ……………...……………………….…. 13
( Substrate-Hot-Electron Injection )
2.3.4帶間穿遂引發熱電子注入 …………….…………………… 13
2.4 簡介氧化層電荷和界面陷阱 ……………....…………………….. 14
2.5影響快閃記憶體可靠性的因素 ……………...…………………… 17
2.5.1資料保存（Data Retention） .……………………………… 17
2.5.2開口萎縮（Window Closure） ……………………………. 18
2.5.3單元干擾（Cell Disturbs） …………………………………. 19
2.5.4不均勻抹去現象 ……………...…………………………….. 20
（Nonuniform Erase Phenomenon）
2.6 結論 …………………………………………………………….. 20
第三章 各類量測技術之探究 ……………………...…………………………… 31
3.1次起始特性量測技巧 ……………...……………………………… 31
3.2閘極衍生汲極漏電流量測 ……………...………………………… 33
（Gate-Induced-Drain-Leakage Current Measurement）
3.3矽基底撞擊游離電流量測 ……………...………………………… 34
（Substrate-Impact-Ionization Current Measurement）
3.4電荷汲引技術 ……………...……………………………………… 35
3.4.1電荷汲引的方式及原理 ……………...…………………….. 35
3.4.2電荷汲引電流量測裝置及設定 …………….……………… 37
3.5側向氧化層缺陷分布萃取技術 …………….…………………….. 39
3.5.1早期方法的回顧 …………….……………………………… 40
3.5.2新方法的原理及程序 …………….………………………… 41
3.5.3單一接面電荷汲引量測 …………….……………………… 42
3.5.4抹去操作所衍生之損傷側向分佈的萃取 ……….………… 47
3.5.5 氧化層電荷的中和 ……………..…………………………... 49
3.5.6 源極偏壓對抹去操作的影響 ……………..……………...… 52
3.5.7 界面陷阱以及氧化層電荷的萃取 ……………...………….. 52
3.5.8 電荷汲引量測與GIDL量測的比較 ……………..………… 54
3.6通道熱載子損害 ……………...…………………………………… 54
3.6.1通道熱載子損傷側向分佈的萃取 …………….…………… 54
3.6.2通道熱載子所衍生之氧化層電荷的中和 …………………. 56
3.6.3通道熱載子所衍生之損害對時間的關係 …………………. 57
3.7 結論 ……………………………………………………………… 57
第四章 二階段中和步驟與電荷汲引曲線數值修正 ……………..……………. 92
4.1實驗目的與緣由 ……………..……………………………………... 92
4.2 二階段中和步驟 …………………………………………………... 93
4.3電荷汲引曲線數值修正 ……………..…………………………….. 97
4.3.1 原理說明 ……………..……………………………………... 97
4.3.2 實驗程序 ……………..……………………………………... 99
4.3.3 實驗結果及討論 …………………………………………... 100
4.4 結論 …………………………….………………………………. 101
第五章 太空元件輻射總劑量測試研究 ……………………….…………….. 115
5.1 實驗目的與緣由 …………...………………………………….… 115
5.2 8051微控制器的基本原理及輻射效應 …………….…………… 116
5.2.1 微控制器的基本原理 ……………..……………………… 116
5.2.2 實驗方法與程序 ………………………………………….. 118
5.2.3 實驗結果與討論 …………………………………………. 120
5.3靜態隨機存取記憶體（SRAM）的基本特性
與輻射效應 …………………………………………………….. 122
5.3.1 SRAM之基本特性 ………………………………………. 122
5.3.2 SRAM特性參數說明 ……………………………………. 123
5.3.3 實驗方法與程序 ………………………………………….. 125
5.3.4實驗結果與討論 …………………………………………. 126
5.4 結論 …………………………………………………….………. 128
第六章 結論與建議 …………………………………………………...……….. 141
6.1 結論 ……………………………………………………………… 141
6.2未來工作與建議 ……..……….………………………….………. 142
參考文獻 ………………………………………………………………………. 144

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