研究生: |
彭育賢 Peng, Yu-Hsien |
---|---|
論文名稱: |
氧化鉿薄膜之電阻式記憶體電阻轉換特性研究 The Resistive Switc hing Characteristics of Resistive Random Access Memory Made by HfOx Thin Films |
指導教授: |
甘炯耀
Gan, Jon-Yiew |
口試委員: | |
學位類別: |
碩士 Master |
系所名稱: |
工學院 - 材料科學工程學系 Materials Science and Engineering |
論文出版年: | 2010 |
畢業學年度: | 98 |
語文別: | 中文 |
論文頁數: | 93 |
中文關鍵詞: | 電阻轉換特性 、電阻式記憶體 、氧化鉿 |
相關次數: | 點閱:1 下載:0 |
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本研究利用射頻磁控濺鍍法在白金(Pt)底電極上鍍製HfOx固態電解質薄膜,並鍍製不同的上電極金屬製作出具有金屬-絕緣層-金屬(MIM)結構的電阻式記憶體。藉由銀(Ag)、銅(Cu)、白金(Pt)三種不同上電極元件的電性分析,探討元件發生電阻轉換現象的可能成因,此外我們還調整了元件固態電解質的厚度以及量測所設定的電流限制值,觀察元件的電阻轉換特性在這些改變下所受到的影響,研究電阻轉換的可能機制。最後,由於電阻式記憶體的電阻轉換行為與離子在固態電解質內部的擴散有關,因此我們將量測元件在不同溫度以及不同定電壓下完成Forming所需要的時間,配合離子跳躍的相關理論,解釋離子在外加電場的影響下,在HfOx固態電解質中移動行為。由實驗結果得到以下重要的訊息:
(一)HfOx的電阻轉換特性是由容易氧化的上電極金屬(銀、銅)所造成,而金屬氧化後所形成的金屬離子能夠藉由電場的影響擴散進入HfOx固態電解質中。(二)Ag/HfOx/Pt元件的電阻轉換機制與導電微通道在固態電解質內部的生成、斷裂、以及復原有關。(三)外加電場會改變離子在固態電解質內部移動時所需要跨越的能障,造成離子的移動速度與電場呈現非線性的提升,降低元件發生電阻轉換所需要的時間。(四)固態電解質薄膜的活化能會影響離子移動的難易程度,因此我們可以藉由薄膜活化能的量測,更加了解元件的各種操作特性。
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