本研究以溶膠凝膠法在ITO玻璃基板上塗佈NiTiO3薄膜。根據XRD顯示NiTiO3為非晶態 (Amorphous)。實驗的第一部分主探討薄膜在未退火的情況下的電阻開關特性表現，我們以Al和Ti做為上電極，透過量測可以發現以Al作為上電極，有單極和雙極兩種電阻開關操作，在單極操作下可以發現Ron/Roff值雖然比較大但是在操作次數上只有40次而且操作電壓變化較大，雙極操作上可以有比較多的操作次數以及更均勻的操作電壓和高低阻值，會有不同的電阻開關特性主要是由不同的Reset機制所導致。以Ti作為上電極可以發現只有雙極操作下才具有電阻開關特性，且 Ron/Roff值小於10，推測是因為上下電極的功函數差所導致。實驗的第二部分我們選擇以表現較好的Al作為上電極和雙極操作模式進行退火的分析，分別進行200 oC、300 oC、400 oC退火，可以發現在退火200 oC下有最高的操作次數，Ron/Roff值也較大，由於退火後氧空缺會被填補，退火後可以發現Vset都比在未退火的情形下更為浮動，而300 oC、400 oC退火下電阻開關特性開始衰退。

In this work, NiTiO3 thin film in metal-insulator-metal stacks was investigated. The NiTiO3 and top electrode was deposited on ITO by Spinning Coating and e-beam, respectively. Al and Ti were deposited as top electrode respectively. The coexistence of both the unipolar and the bipolar RS mode is observed for the Al/NiTiO3/ITO device. On the other hand, there is only unipolar RS mode is observed for the Ti/NiTiO3/ITO. Then, we chose the Al/NiTiO3/ITO device to analyze the film annealed with different temperature. Through the analysis of XPS, further understanding on the resistivity of our device can be studied. By assuming that the conductive filaments can be mostly controlled by the oxygen vacancies. By different annealing temperature, we can control the quantity of oxygen vacancies in NiTiO3 layer. The effects of the different RS mode and annealing temperature of NiTiO3 will be discussed.

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