在科技發達的現代社會中，仰賴大量計算及儲存空間的物聯網、AI和大數據相關的科技也不斷的在發展，使得我們對記憶體的講究和需求也日趨上升，其中，電阻式記憶體(RRAM)結構簡單、易於微縮、低功耗、高速操作等諸多優點，使其成為下一代非揮發性記憶體的有利候選。
本實驗以磁控濺鍍法將鈦酸鋇(BaTiO3)及鐵酸鉍(BiFeO3)鍍製在ITO基板上，分別製作單介電層元件: Al/ BaTiO3/ITO 和 Ag/ BaTiO3/ITO ; 以及雙介電層元件: Al/ BaTiO3/ BiFeO3/ITO 和 Ag/ BaTiO3/ BiFeO3/ITO。其中在製作雙介電層元件時的退火製程分為雙層主動層一起退火及各別退火，藉由元件的記憶體電性表現嘗試探討一起退火及各別退火對雙主動層元件的的影響。
電性量測方面利用半導體參數分析儀(Agilent B1500A)量測電阻式記憶體元件的電流-電壓特性曲線(I-V curve)及元件穩定性，透過量測，我們可以發現雙主動層元件在reset時的電流會呈現階段性的下降，日後或許可以利用這個特色來使RRAM達到多階記憶(multi-level memory)的效果，另外主動層各別退火的元件在電性持久度上較兩層主動層一起做退火的元件來的好，Ag/ BaTiO3/ BiFeO3/ITO 元件的開關電流比值(on/off ratio) > 50 ，並且在高、低阻態的維持時間都能超過10000秒，其開關切換次數也穩定的來到1500次。
除了一般的RRAM電性量測外，我們也對鍍製出的鈦酸鋇及鐵酸鉍薄膜進行XRD及XPS分析，另外，本論文也對參與RRAM燈絲傳導機制的歐姆傳導、空間電荷侷限電流(SCLC)稍作探討。

Today, in the era of advanced technology, the IoT, AI, and big data which heavily depend on the number of calculations and storage spaces, have also been developed to address the looming demands. Owing to the advantages of simple structure, low power consumption, and rapid operation speed on data reading and writing, random resistive memory (ReRAM) stands out among the available types of memory.
In this research, BaTiO3 target and BiFeO3 targets are prepared and then sputtered on ITO substrate to realize a single active layer: Al/ BaTiO3/ITO and Ag/ BaTiO3/ITO, as well as dual active layers: Al/ BaTiO3/ BiFeO3/ITO and Ag/ BaTiO3/ BiFeO3/ITO. For the operation of dual active layers, the impacts of the different annealing environments on the memory properties of the devices are investigated. The annealing process is handled in two separate approaches for comparison: either annealing both layers of this dual-layer stack concurrently, or annealing each layer separately.
For the aspects of the electrical characteristics, the I-V curves, the endurance, and the memory retention of the devices are probed by a precision semiconductor parameter analyzer (Agilent B1500A). It is found that the current of devices with dual active layers has manifested a two-step decline during the reset process, which may have a unique potential for realizing the multi-level memory of ReRAM in the future. Additionally, the ReRAM memory endurance of the dual-stack device with each of the active layers annealed separately has outperformed the one with active layers that are annealed together. Also, the on-off switching current ratio of Ag/ BaTiO3/ BiFeO3/ITO is in the excess of 50, and the retention time in both high and low resistance states could be maintained for more than 10000 seconds, while during the endurance test, over 1500 switching cycles are also realized.
In addition to the measured electrical properties, XRD and XPS analyses of BaTiO3 and BiFeO3 thin film are also performed. A follow-up discussion on the filament conduction mechanisms responsible for the observation of the high and low resistance states, including the ohmic conduction, and space charge limited current (SCLC) is presented.

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