本論文中，以一些常見的氧化物做為電阻式隨機存取記憶體的氧化層，在材料的選用上，主要以高絕緣並且為半導體產業常使用的氧化物為主。
首先，在室溫下，我們探討以TiO2 做為阻值轉換層的電阻式記憶體的製備方法與電特性。因為實驗內容探討退火對元件產生的影響，因此以X光光電子能譜儀(XPS)分析射頻磁控濺鍍所製備的TiO2 薄膜，分析所獲得的數據曲線，可以確認此薄膜是以TiO2 在各種退火溫度下的組成改變趨勢。製備完成的元件，在100毫伏電壓的操作下，可在有著雙極性電阻轉換特性的直流操作下運作超過1000次的次
數，並且有著超過10000 秒的穩定記憶特性。根據動態與靜態量測的數據中，計算標準差探討退火製程對所備製的電阻式記憶體造成的效益，而利用累積概率能了解元件在靜態量測下的表現。

另一部分，本論文以Pt/MgZnO/Pt與ITO/MgZnO/Pt為架構的電阻式隨機存取記憶體的製備方法與電特性。製備完成的記憶體，能夠完成超過500次的操作次數，會在100毫伏電壓下，有著超過10000 秒的穩定記憶特性，並有雙極性電阻轉換特性。利用分析電流-電壓曲線，可以探討載子的傳導機制；在Set過程中，起初電壓電流呈現一次線性關係，在逐漸增加電壓的過程中，電流隨電壓上升的幅度趨緩且為與電壓平方成正相關，此時傳導機制進入空間電荷限電流值，最後當電壓到達VSET，導電路徑成功形成，元件進入導通狀態。

最後，為了達到更好的高阻態與低組態之穩定性，我們研究以ITO/TiO2/MgZnO/ITO 的雙層氧化物結構之電阻式記憶體開關電特性。製備完成的元件，一樣表現出雙極性電阻轉換特性，並有效降低在高電阻態與低電阻態的標準差，且維持優良的記憶體開關比，意味著雙層結構是改善記憶體特性的重要方法之一。

In this thesis, a few kinds of common and high-κ oxide-based materials are applied as the resistive switching layers of resistive random access memory (RRAM) devices and the characteristics are investigated.
In the beginning, the fabrication and characterization of the devices with TiO2 resistive switching layers are reported. In order to research in how annealing temperature influences RRAM devices, we analyze X-ray photoelectron spectroscopy (XPS) spectrum of the annealed TiO2 films fabricated by RF sputter to confirm the TiO2 phase and investigate the trend. The fabricated devices exhibit over one thousand DC switching cycles and shows bipolar resistance switching behavior. Moreover, stable retention test for over 104 s under a 100 mV stress is carried out successfully. According to dynamic and static test, we calculate the standard deviation to explore how annealing process impacts on RRAM devices. Furthermore, cumulative probability plots demonstrate the static performance of the devices.
The other part is described the fabrication and analysis of the RRAM cell with Pt/MgZnO/Pt and ITO/MgZnO/Pt structures. The fabricated device shows over five hundreds DC switching times and displays stable retention test for over 104 s under 100 mV stress that exhibits bipolar switching behavior. With I-V curves fitting method, we can analyze the conductive mechanism of the devices. In set process is firstly dominated by Ohmic conduction since current is proportional to applied voltage and then transforms to the space-charge-limited-current(SCLC) process which current is proportional to square of applied voltage in the high resistance state. Finally, conduction filaments form successfully and turns into low resistance state when applied voltage sweeps to VSET.
Finally, in order to improve stability of high resistance state and low resistance state, we investigate the characteristics of bilayer (two oxide layer) structure : ITO/TiO2/MgZnO/ITO RRAM device. The fabricated device shows bipolar switching behavior as well and bring forth lower standard deviation of high resistance state and low resistance state; moreover, it can maintain good ratio of RHRS /RLRS. The bilayer structure reveals a critical method to improve the characteristics of RRAM devices.

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