這篇論文旨在探討電阻式記憶體（RRAM）的製作及其性能，特別是以摻雜離子的氧化鐵薄膜作為電阻切換層的應用。研究中採用了多種材料特徵技術，包括X光繞射（XRD）和X射線光電子能譜（XPS），以深入分析材料的品質與特性。

在第一部分，我們利用濺鍍法製作電阻切換元件，並研究其在電流與電壓特性方面的表現。具體而言，製備了具有電阻切換特性的Fe2O3及其Ag摻雜版本。研究結果顯示，Ag的摻雜顯著提升了元件性能。測試結果表明，資料保持時間可達104秒以上，且電阻的開/關比率約為10³。平均設置電壓和重置電壓分別為0.94V和-1.35V。性能的提升主要歸因於氧空位與Ag原子之間的相互作用，這促進了導電絲的形成。XPS分析顯示，隨著Ag的摻雜，氧空位的數量顯著增加，進一步提升了元件性能。此外，Ag原子作為陷阱中心，能夠更有效地捕獲和釋放電荷，進一步促進導電絲的形成。因此，Ag摻雜的Fe2O3在RRAM元件中展現出良好的應用潛力。

在第二部分，我們探討了使用射頻濺鍍系統製作的ITO/Cu摻雜Fe2O3/ITO薄膜電阻式記憶體（RRAM）。XRD圖譜顯示，Cu:Fe2O3薄膜具有菱面體結構，且未檢測到銅的二次相或雜質相。在設置電壓（Vset）方面，Cu:Fe2O3薄膜的標準偏差和平均電壓分別為-1.98V和0.92V，而重置電壓（Vreset）的數值分別為0.39V和1.31V。Cu:Fe2O3薄膜的電阻開關週期及資料保持測試結果顯示，其開/關比為39.1，保持時間超過104秒，表明Cu摻雜的Fe2O3薄膜能有效改善RRAM性能。

此外，還分析了氧化鐵薄膜在電阻式記憶體中的特性。實驗結果顯示，氧化鐵薄膜具備優異的可程式設計性和穩定性，適合用於電阻式記憶體的製備。透過調控氧化鐵薄膜的結構與生成過程，可以有效提升記憶體性能，為其在實際應用中的推廣提供有力的研究參考。

本研究的意義在於，通過對不同摻雜元素的引入和材料特性的深入分析，我們能夠更全面地理解和優化RRAM的性能。Ag和Cu摻雜的氧化鐵薄膜在電阻切換特性上的顯著改善，為未來高性能RRAM的開發提供了新的思路和方向。這不僅有助於提升記憶體的資料保持能力和開關週期，還能有效降低操作電壓，提升整體能源效率。

未來的研究可以進一步探討不同摻雜元素及其濃度對RRAM性能的影響，並嘗試將這些技術應用於其他類型的記憶材料。此外，還可以研究不同製程條件對薄膜結構和性能的影響，以尋找最佳的製作工藝。這些研究將有助於推動RRAM技術的商業化應用，並在更廣泛的電子設備中實現高效和穩定的資料存儲。

This paper aims to investigate the fabrication and performance of resistive random-access memory (RRAM), particularly the application of iron oxide thin films doped with ions as the resistive switching layer. Various material characterization techniques, including X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), were employed to thoroughly analyze the quality and characteristics of the materials.

In the first part, we fabricated resistive switching devices using the sputtering method and studied their current-voltage characteristics. Specifically, we prepared Fe2O3 and its Ag-doped versions with resistive switching properties. The research results indicated that Ag doping significantly enhanced the device performance. The test results showed that the data retention time could exceed 104 seconds, and the resistance on/off ratio was about 10³. The average set voltage and reset voltage were 0.94V and -1.35V, respectively. The performance enhancement was mainly attributed to the interaction between oxygen vacancies and Ag atoms, which facilitated the formation of conductive filaments. XPS analysis revealed that the number of oxygen vacancies significantly increased with Ag doping, further improving the device performance. Moreover, Ag atoms acted as trap centers, effectively capturing and releasing charges, further promoting the formation of conductive filaments. Therefore, Ag-doped Fe2O3 demonstrated good application potential in RRAM devices.

In the second part, we investigated the ITO/Cu-doped Fe2O3/ITO thin-film RRAM fabricated using the RF sputtering system. XRD patterns showed that the Cu:Fe2O3 film had a rhombohedral structure, with no secondary phase or impurity phase of copper detected. In terms of set voltage (Vset), the standard deviation and average voltage of the Cu:Fe2O3 film were -1.98V and 0.92V, respectively, while the reset voltage (Vreset) values were 0.39V and 1.31V, respectively. The switching cycle and data retention tests of the Cu:Fe2O3 film showed an on/off ratio of 39.1 and a retention time exceeding 104 seconds, indicating that Cu-doped Fe2O3 films could effectively improve RRAM performance.

Furthermore, we analyzed the properties of iron oxide thin films in resistive memory. The experimental results showed that iron oxide thin films have excellent programmability and stability, making them suitable for the fabrication of resistive memory. By adjusting the structure and fabrication process of iron oxide thin films, memory performance can be effectively enhanced, providing valuable research references for their practical application.

The significance of this study lies in the comprehensive understanding and optimization of RRAM performance through the introduction of different dopant elements and in-depth analysis of material properties. The significant improvements in the resistive switching characteristics of Ag and Cu-doped iron oxide thin films provide new ideas and directions for the development of high-performance RRAM in the future. This not only helps to enhance data retention capability and switching cycles of the memory but also effectively reduces operating voltage, thereby improving overall energy efficiency.

Future research can further explore the effects of different dopant elements and their concentrations on RRAM performance and attempt to apply these techniques to other types of memory materials. Additionally, studying the impact of different fabrication conditions on thin-film structure and performance could help identify the optimal manufacturing process. These studies will contribute to the commercialization of RRAM technology and the realization of efficient and stable data storage in a broader range of electronic devices.

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