本論文以共濺鍍系統製作氧化鎂基底薄膜之電阻式記憶體元件。其結構為金屬鋁電極/氧化鎂基底薄膜(MgO-based)/氧化銦錫(ITO)。首先我們沉積未摻雜的氧化鎂薄膜，利用氧化鎂的穩定性製作電阻式記憶體。當薄膜厚度為30奈米且在真空環境中進行退火，元件有出色的性能。經由電特性分析，阻態的切換行為主要由氧空缺的導電燈絲形成與斷裂控制。在低阻態時電流傳導機制為歐姆傳導，在高阻態時為蕭基發射電流傳導機制。元件在有切換特性前需要一個電鑄過程(VForming = -9.4V)，而在後續切換行為有低的操作電壓(VSET = -0.78V，VRESET = 0.98V)。在200次的切換過程中有相對密集的電流分布，其電流開關比大約為1.5×103。
而後透過共靶濺鍍銦摻雜，進一步使記憶體性能有所提升。通過銦的摻雜，因為缺陷的增加、增加薄膜中的載子濃度，使元件轉變為免電鑄過程(Forming-free)之元件。因為避免了電鑄過程，減少了薄膜的崩潰，使元件有更好的穩定度和可靠性。找出氧化鎂功率100W，氧化銦功率40W為最佳功率比例，同時保持低的操作電壓(VSET = -0.88V，VRESET = 0.32V)。然而因為銦摻雜使高阻態的電阻值降低導致電流開關比降低兩倍為5.02×102
最後進行不同氣氛退火條件，發現在氧氣環境中進行退火改變氧空缺濃度之元件有最佳的記憶體性能表現。元件的操作電壓並沒有明顯的變化(VSET = -0.86V，VRESET = 1.08V)。並且有好的可靠性，切換次數超過了1000次，和好的資料保存性(超過104秒)。然而因為在氧氣環境中退火使在低阻態時導電燈絲沒有一個完整的路徑連接上下電極，使電流在低阻態時有些微的降低。開關比相較於在真空環境中退火的元件大約降低5倍為1.51×102，雖然開關比降低但還是足以在二進制記憶體裝置中區分0和1。

In this thesis, the MgO-based thin film was fabricated by co-sputtering. The resistive memory structure is Al / MgO-based thin film / ITO. First of all, we deposit undoped magnesium oxide thin film, and take advantage of the stability of magnesium oxide to make resistive memory. When the film thickness is 30nm and annealed in a vacuum environment, the device has excellent performance. Through the analysis of electrical characteristics, the switching behavior of the resistance state is mainly controlled by the formation and breakage of the oxygen vacancy conductive filament. The current conduction mechanism is ohmic conduction in the low resistance state, and the Schottky emission current conduction mechanism in the high resistance state. The component requires an electroforming process (VForming = -9.4V) before it has switching characteristics, and a low operating voltage (VSET = -0.78V, VRESET = 0.98V) in the subsequent switching behavior. During the 200 times switching cycle, there is a relatively dense current distribution, and the ON/OFF ratio is about 1.5×103.
Then, through the doping of indium, because of the increase of defects and the increase of the carrier concentration in the thin film, the device is transformed into a forming-free device. Due to the electroforming process is avoided, the collapse of the film is reduced, and the device has better stability and reliability. Magnesium oxide power of 100W and indium oxide power of 40W is the best power ratio, while the device maintaining a low operating voltage (VSET = -0.88V, VRESET = 0.32V). However, indium doping reduces the resistance value of the high-resistance state, resulting in a 2-fold reduction in the ON/OFF ratio of 5.02×102.
Finally, annealing conditions in different atmospheres were found, and it was found that the film annealed in an oxygen environment have the best memory performance. The operating voltage of the device does not change significantly (VSET = -0.86V, VRESET = 1.08V) And it has good reliability, the number of switching cycle exceeds 1000 times, and good data retention (over 104 seconds). However, due to annealing in an oxygen environment, the conductive filament does not have a complete path to connect the top and bottom electrodes in the low resistance state, so that the current is slightly reduced in the low resistance state. Although the ON/OFF ratio is reduced, it is still sufficient to distinguish between 0 and 1 in a binary memory device.

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