電阻式記憶體因具有快速的讀寫能力以及長久的資料保存時間，且元件微縮度高，在新式非揮發記憶體的研究上受到矚目。但是，電阻式記憶體仍有許多需要改進的地方，其中最大的問題在於電阻轉換因子（如轉換電壓與高低阻態等）的不穩定分布。為了解決這個問題，學者們紛紛構思新的製程與方法，例如離子摻雜、嵌入奈米級晶體、雙層式結構……等，皆獲得不錯的效果。其中，於上下電極之間堆疊兩層固態電解質薄膜的雙層式結構，因製程簡單方便，可在全室溫環境下製作，而成為改善元件轉換特性的重要指標。
本研究採用室溫製程，以TiO2與HfO2作為固態電解質材料，並使用射頻磁控濺鍍法分別製作了單層的Pt/TiO2/W、Pt/HfO2/W，以及雙層的Pt/TiO2/HfO2/W等電阻式記憶體，並進行電性量測。在比較單層與雙層結構之間的差異後，我們藉由改變固態電解質厚度與薄膜倒置堆疊等方法，獲得了雙層式元件最佳的實驗參數。最後，將量測所得的數據進行整理，我們推導出雙層式結構內部的導電微通道成長模型，以及雙極性轉換機制圖，以闡明元件的電阻轉換原理。
從實驗結果，我們可以歸納出幾點結論：（一）單層式元件由於高低阻態的變動性過大，無法進行長次數的電阻轉換；利用雙層固態電解質堆疊的結構，可以有效改善元件電阻態分布不均的問題。（二）對雙層式元件進行厚度參數的變化後，我們得到Pt/TiO2（40 nm）/HfO2（40 nm）/W的元件具有最佳的轉換行為，且此元件在85。C下可擁有約2 × 104秒以上的資料儲存時間。（三）利用氧空缺導電通道成長模型，可說明雙層式結構能夠抑止多條平行導電絲生成，促使單一導電絲斷裂與再生成行為的局部區域化。（四）Pt/dielectric/W類型的RRAM元件，在正負偏壓下的電致現象皆為空間電荷限制電流機制，但兩者使電子流動的方式與過程並不相同，這個現象主要是由於上下電極之間的功函數差值所致。

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