本研究以溶膠凝膠法在ITO玻璃基板上塗佈Mg2TiO4薄膜。根據XRD顯示Mg2TiO4為非晶態 (Amorphous)。第一部分探討Mg2TiO4薄膜以Al/ Mg2TiO4/ ITO (MIM)結構下之不同退火溫度的電阻轉換特性。在未退火與退火200oC時觀察到單極性電阻轉換，未退火Al/Mg2TiO4 (30 nm)/ITO轉換次數約為30次且Ron/Roff達103，退火200oC Al/Mg2TiO4 (30 nm)/ITO轉換次數約為50次且Ron/Roff達105，電阻轉換特性隨著退火溫度升高而變好，且透由SIMS分析，了解到退火300oC無電阻轉換特性之原因可能來自於In離子的過渡擴散。第二部分則以不同厚度之Mg2TiO4薄膜 測量Al/Mg2TiO4/ITO (MIM)結構之電性，在一定厚度 (10/30 nm)下，才能夠觀察到單極性電阻轉換，未退火Al/Mg2TiO4 (10 nm)/ITO轉換次數約為25次且Ron/Roff 102，Al/Mg2TiO4 (10 nm)/ITO則無電阻轉換特性，藉由漏電流機制分析，高阻態由SCLC所主導，低阻態則是由歐姆傳導機制所主導。為了更了解內部電阻轉換的形式，以XPS表面分析，結果顯示轉換機制應是由氧空缺所控制。Mg2TiO4薄膜與上電極Al的接面處可能產生interfacial layer，推測其為操作電壓Vset上升的原因。

In this work, Mg2TiO4 thin films in metal-insulator-metal stacks was investigated. The Mg2TiO4 and top electrode was deposited on ITO by Spinning Coating and e-beam, respectively. Al/Mg2TiO4/ITO MIM thin films with unipolar resistive switching was successfully fabricated. Through the analysis of XPS; SIMS and fitting of conduction mechanism, further understanding on the resistivity of our device can be studied. Bu assuming that the conductive filaments can be mostly controlled by the oxygen vacancies. The effects of the thickness and annealing temperature of Mg2TiO4 will be discussed.

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