本研究以射頻濺鍍法在ITO玻璃基板上濺鍍氧化鈮薄膜。根據XRD顯示氧化鈮薄膜皆為非晶性(Amorphous)。第一部分探討氧化鈮薄膜不同退火溫度之電阻轉換特性，並製成ITO/NbOx/Al(MIM)元件作為記憶單元。在退火300/400/500°C觀察到單極性電阻轉換，且隨退火溫度增加，電阻轉換表現更好。第二部分則以不同氧化鈮薄膜厚度量測ITO/NbOx/Al之電性。在一定厚度(25/50nm)下，才能觀察到單極性電阻轉換， ITO/NbOx(50nm)/Al轉換次數18次且RON/ROFF達104，ITO/ NbOx (25nm)/Al轉換次數達33次且RON/ROFF達105，藉由漏電流機制分析，高阻態皆由SCLC主導，低阻態由歐姆傳導機制主導。為了更了解內部電阻轉換的形式，以XPS縱深分析，結果顯示轉換機制應是由氧空缺所控制，並在NbOx/Al的接面處產生interfacial layer，推測其為電阻轉換發生的位置。第三部分為改變上電極材料，以Ti和複合電極Ti/Pt取代Al電極，ITO/ NbOx/Ti電阻轉換特性不明顯，而ITO/ NbOx/Ti/Pt觀察到雙極性電阻轉換，轉換次數22次且RON/ROFF約為104。高阻態IISchottky主導，低阻態由歐姆機制主導，說明複合電極可調變功函數並改善電阻轉換特性。

In this work, we fabricated niobium oxide thin films in metal-insulator-metal stacks. The niobium oxides and the top electrodes were deposited on ITO by RF sputtering and e-beam respectively. We successfully fabricated ITO/NbOx/Al MIM thin films with unipolar resistive switching. Through the analysis of XPS and fitting of conduction mechanism, we can further understand the resistive switching in our device. We assume that the conductive filaments can be mostly controlled by the oxygen vacancies. The effect of the thickness of NbOx will be discussed. Besides, we also change the top electrode to observe the resistive switching. Bi-layer Ti/Pt shows bipolar resistive switching and with better performance than Ti only. It could be related to the work function differences and bi-layer could alter the work function.

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