本論文是以氧化鉿/鈦化氮/二氧化矽/矽為基板探討上電極效應、電流傳導機制與熱退火效應。在討論上電極效應部分,從鎢及鎢/鈦上電極之結果發現,鎢上電極使元件呈現單極性操作,而鎢/鈦上電極使元件呈現雙極性操作。這裡說明不同的上電極會造成元件操作模式不同,同時鎢/鈦是一個良好的上電極選擇。經過電流傳導機制之討論後,我們可以發現元件在低阻態時是歐姆傳導,而在高阻態時,低電壓區是歐姆傳導,高電壓區是普爾-法蘭克發射。從以上的分析我們可以更了解元件處於高阻態與低阻態時的電流傳導機制。最後在熱退火效應方面,我們可以發現在適當製程溫度條件下可以使耐久度獲得十倍的提升。透過此方法改善使電阻式記憶體更具有發展的潛力。
In this thesis, we discuss on the top electrode effect, current conduction mechanism and annealing effect for the HfO2 based RRAM. At the discussion of the top electrode effect, the W top electrode causes the device to present unipolar operation, but in the W/Ti top electrode present bipolar operation. We may know that top electrode influence the switching characteristic and the polarity of RRAM seriously. Second, the W/Ti/HfO2/TiN device in LRS is the ohmic conduction, but when HRS, the low voltage region (<0.05V) is the ohmic conduction, the high voltage region (>0.1V) is Poole-Frenkel emission. Finally, in the annealing effect, the suitable temperature condition to obtain the 10 times of promotion in endurance. From the result of the annealing effect, we can provide a method to improve endurance and have the development potential.