本研究以射頻磁控濺鍍法在透明ITO玻璃基板上沉積非晶態的鑭釓氧(LGO)薄膜，並鍍上金屬上電極製成Al/LGO/ITO元件以觀察其電阻轉換特性。第一部分討論不同LGO介電層厚度(25/55/95 nm)之特性表現，在25 nm時能觀察到較好的單極轉換特性，轉換次數到達110次，Ron/Roff約為105。第二部份我們藉由觀察不同的沉積氣氛比例(Ar:O2)所形成之薄膜，並討論氧空缺對元件特性的影響，當通入O2的比例大於20%時會使薄膜沉積速率降低，膜厚變薄且薄膜內氧空缺增加，因此所形成的導電燈絲較粗，使所需的操作電壓上升也使操作次數下降。第三部分在薄膜退火處理方面，退火溫度提高使擴散至介電層中的In離子比例增加，In離子與氧空缺一起形成導電燈絲可減少在SET過程所需施加的電壓，當退火溫度為400oC時能有效的使操作電壓降低且更穩定，操作次數達到452次，Ron/Roff維持在約104，有最好的電阻轉換特性。最後以不同上電極(Al、Ti)之元件來加以分析其導通機制，兩種電極的高阻態及低阻態都分別為Schottky及歐姆導通主導，Ti/LGO/ITO同樣具有單極轉換特性，但特性表現不佳，說明其轉換特性與其上電極和介電層的功函數差有關。

In this study, we deposited the amorphous LaGdO3 thin films on by RF sputtering, and the unipolar resistive switching (URS) properties in Al/LGO/ITO structure was investigated. Through different deposition atmosphere Ar/O2 ratios and thicknesses, we assume that the conductive filaments can be mostly dominated by oxygen vacancies. Besides, the RS characteristics and operating voltage were improved after annealing. It’s speculated that the In ions diffused by ITO participate in the formation of the filaments. Finally, we change the top electrode to investigate the conduction mechanism. The current conduction mechanism of the device in LRS and HRS were found to be dominated by the Ohmic behavior and Schottky emission respectively. It was also confirmed that the potential barrier height between top electrode and LGO is a significant factor on the RS characteristics.

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