本研究利用射頻磁控濺鍍法在Si基板上沉積Gd2O3薄膜並利用電子束蒸鍍法鍍製不同金屬做為上電極，形成金屬-介電-半導體(MIS)結構。本實驗分成三部分，第一部分探討Gd2O3薄膜在不同退火溫度及氣氛下的物理特性。由實驗可知，與空氣退火相比，薄膜在氮氫混合氣氛下退火能夠產生較多氧空缺，且由XPS可驗證隨著退火溫度升高，非晶格氧的特徵峰訊號增強並往高束縛能偏移。本實驗中，Gd2O3薄膜具有n型半導性，並且在氮氫退火800oC時載子濃度最高。TEM橫截面影像發現Al/Gd2O3與Gd2O3/Si界面皆有一層氧化層，且在氮氫退火後Gd2O3/Si界面層厚度會明顯增加。
第二部分探討的是不同退火溫度對Al/Gd2O3/Si異質接面整流特性的影響。根據實驗結果，Al/Gd2O3/Si在經過氮氫退火(600-900oC)之後皆具有整流的效果，然而經過理想因子的計算過後，得知氮氫800oC下的接面性質較符合理想二極體，元件的整流的特性由p-n接面主導。另外，探討不同上電極(Al、Ti、Cr及Au)對電性的影響時，可以發現功函數小的金屬材料具有較大的漏電流，且皆具有整流特性，並且除了Ti上電極，其他金屬的整流特性都由p-n接面所主導。
最後將探討Metal/Gd2O3/Si元件的電阻轉換特性，由實驗結果得知，經過氮氫800oC退火處理後，元件具有較佳的電阻轉換特性，足夠的氧空缺使得薄膜更容易形成導電路徑，使得所需要的操作電壓降低，並且開關比在-0.5V下可達到104。同樣選擇上電極功函數小者，界面處形成的能障較小，可在相對較小的電壓下作電阻的切換。

The purpose in our study is to discuss the characteristic of rectification and resistive switching of a self-rectifying device in RRAM. In this study, the Gd2O3 thin films are deposited on Si substrates by RF magnetron sputtering and various metal top electrodes are fabricated by E-beam evaporator to form metal-insulator-semiconductor structures. According to the result, more oxygen vacancies in the n type semiconducting Gd2O3 thin film are produced under N2-H2 annealing. The rectifying ratio of Al/Gd2O3/Si device with 800oC annealing in N2-H2 can reach 6 orders and the resistive switching property has the lowest Set voltage as well as ON/OFF window with 4 orders. Therefore, the Al/Gd2O3/Si device is considered as one of the potential structures in self-rectifying RRAM.

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