| 研究生: |
吳祐紳 Wu, You-Shen |
|---|---|
| 論文名稱: |
溶膠凝膠法備製ZrCeOx薄膜於電阻式記憶體之應用 Research of Sol-Gel Derived ZrCeOx Thin Films for RRAM Applications |
| 指導教授: |
黃正亮
Huang, Cheng-Liang |
| 學位類別: |
碩士 Master |
| 系所名稱: |
電機資訊學院 - 電機工程學系 Department of Electrical Engineering |
| 論文出版年: | 2020 |
| 畢業學年度: | 108 |
| 語文別: | 中文 |
| 論文頁數: | 102 |
| 中文關鍵詞: | 溶膠凝膠法 、ZrCeOx薄膜 、電阻式記憶體 |
| 外文關鍵詞: | Sol-gel, ZrCeOx thin film, RRAM, Polycrystalline |
| 相關次數: | 點閱:93 下載:0 |
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本研究利用溶膠凝膠法製備ZrCeOx薄膜,並塗佈在ITO玻璃基板上,再使用電子束蒸鍍法鍍上金屬作為頂電極,製程出金屬-絕緣層-金屬(MIM)結構之電阻式記憶體。本研究分成兩部分,第一部分討論ZrCeOx薄膜在未退火的情況下,改變薄膜厚度與頂電極(Al、Ti)的變因之下,其元件電阻切換特性之影響,透過量測可發現僅有一層與兩層之薄膜製程之元件具有電阻切換特性,且以Al作為頂電極之元件有較佳的電阻切換特性,皆為負開正關之雙極切換機制,其操作次數約為150次,Ron/Roff值皆有大於101,薄膜厚度增加可能造成電阻值上升導致並未產生電阻切換機制。以Ti作為頂電極之元件,其操作次數約為60次,且Ron/Roff值小於101,推測是因為上下電極之功函數差所致。
在第二部分,我們選擇電阻切換特性較好的Al作為頂電極,分別進行200 ℃、300 ℃、400 ℃之退火製程,探討薄膜經過退火製程後對元件電阻切換特性的影響,經量測發現皆為負開正關之雙極切換機制,在退火溫度為400 ℃之元件有最佳的電阻切換特性,其操作次數高達646次,雖然Ron/Roff值隨著退火溫度的上升有變窄的趨勢,但仍維持101足夠的寬度分辨高低阻態。由於薄膜經過退火製程後,銦離子的擴散與薄膜內之氧空缺量增加,使導通燈絲更容易形成,產生操作電壓降低,操作次數明顯上升,元件因而有更佳的穩定度與可靠度。
Amorphous ZrCeOx thin films were prepared by sol-gel method and the resistive switching (RS) properties of sol-gel derived Al/ZrCeOx/ITO devices were investigated. The influences of annealing temperature, film thickness, and top electrode on the RS properties were also discussed. It is found that the 2 layered thin film annealed at 400 ℃ can operate up to 643 times. In addition, as the number of coating layers increases, the repeatability of the components becomes more stable. However, On/Off ratio and retention times were not affected by the number of coating layers or with/without annealing. The On/Off ratio values are all in between 101 and 102, and the retention times are up to 104 seconds. The reason for the large increase in the number of operations after annealing is likely attributed to the diffusion of In ions from ITO substrate to ZrCeOx film and the increased oxygen vacancies, which would allow the discontinuous ions to fit into the connecting process of the formation of filaments. In addition, the conduction mechanism could be classified into ohmic conduction in the low resistance state and space-charge-limited current conduction mechanism in the high resistance state.
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