本論文提出創新的漂移式臨界電壓模型以正確描述現今及未來金氧半電晶體的開關行為，解決了傳統2□B臨界電壓模型無法應用在各式新穎結構之金氧半電晶體的問題。當元件微縮至奈米級尺度，各種元件設計與架構使得電晶體的切換特性不再與基底摻雜濃度相關，使得傳統以反轉電荷定義之臨界電壓模型無法再適當合理地描述金氧半電晶體的開關行為。
在此論文中，臨界電壓的定義不再傳統地依據反轉電荷量的多寡，而是提出由漂移與擴散電流之大小關係決定。由於漂移電流與擴散電流分別主導了金氧半電晶體其導通與關閉電流之行為，因此在兩者相當的情況下，可作為理想之臨界電壓位準。相對於傳統2□B臨界電壓模型，漂移電流式臨界電壓模型下之臨界電壓不再由『電荷』決定，而是直接以『電流』觀點來分析元件的導通與關閉行為，如此，不只在解析上提供了更具有物理意義的定義，並回歸到電路操作上根本的電流作用。
漂移電流式臨界電壓模型，透過對帕松方程式求解，確實的解出漂移電流與擴散電流，進一步得到臨界電壓及電流之值。透過適當的數學分析，各種元件設計及架構，皆能得到符合於模擬結果之解析解。此新臨界電壓模型不僅適用於各式典型或非典型的單、多閘極金氧半電晶體，對採用新閘氧層或新通道層的未來架構，皆能給出適切的臨界電壓解析模型，其相應的臨界電流並能提供作為臨界電壓實際量測之電流標準。

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