近年來，隨著AI、物聯網以及大數據等等科技的蓬勃發展，需要大量的計算以及儲存空間，記憶體的要求以及需求也日益增加，由於電阻式記憶體(ReRAM)具有結構簡單、低功耗、讀寫速度快等優點，但要如何達到高密度、低功耗的記憶體，一直是一個待解的議題。
為了達到高密度的需求，本論文製備了1×1和2×2交叉式陣列電阻記憶體，使用射頻磁控濺鍍法製備的鐵酸鉍薄膜作為介電層材料，上、下電極分別為氧化銦錫和鋁，並量測此結構ReRAM電性及穩定性，經由量測，此元件具有能辨識的開關電流比值(on/off ratio > 100)，接著在高、低阻態維持時間都可以維持11000秒以上，並且在耐用度測試上，可以穩定的達到約200次的開關切換次數。
除了一般的電性量測分析，也對鐵酸鉍薄膜進行XRD和吸收等量測，並計算其能隙，本論文也探討了其燈絲傳導機制以及高、低阻態的導通機制，除了歐姆傳導、空間電荷侷限電流外(SCLC)，發現在高電場下的傅勒-諾德翰穿隧(Fowler-Nordheim Tunneling)也有參與其中。
接著探討電阻式記憶體對光之響應，以及不同波段的光對元件的影響，
進而去探討在紫外光下，進行元件阻態切換，以及低阻態的電流變化。

In recent years, the demand for IoT, big data, and AI have increased phenomenally, all come at the expense of requiring an astronomical amount of computing power and storage memory. With various types of memory considered, resistive memory (ReRAM) stands out due to its inherent advantages including a simple structure, low power consumption, and fast read and write speed.
To create a plausible ReRAM, the present work has prepared 1×1 and 2×2 crossbar arrays of ReRAM based on a bismuth ferrite film as prepared by radio frequency magnetron sputtering as the dielectric layer material, the top and bottom electrodes adopted are indium tin oxide(ITO) and aluminum(Al), respectively. The electrical properties and stability of the crossbar ReRAM are measured and the subsequent results have revealed in a sequence that the device has a recognizable switching current ratio (on/off ratio > 100), the retention time in both high and low resistance states could be maintained for more than 11000 seconds, while during the endurance test, over 200 switching cycles are also realized.
In addition to the general electrical measurement and analysis, XRD and absorption measurements are also performed on the bismuth ferrite film to determine the energy gap. This thesis also discusses the filament conduction mechanism that dictates the high and low resistance states, including the ohmic conduction, space charge limited current (SCLC), and Fowler-Nordheim tunneling under a high electric field.
Finally, the response of ReRAM under illumination and in particular with the influence of illumination of different wavelengths on the device are also discussed to investigate their impacts on the resistance switching of ReRAM and in particular the current in the low-resistance state under the ultraviolet irradiation.

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