2011 年，氧化鉿（HfO2）被發現具備鐵電特性後，該材料便吸引了廣泛關注，與傳統鐵電材料相比，氧化鉿即使在 10 nm 級別的厚度下仍然能夠保持穩定的鐵電性，這主要歸功於其獨特的晶相轉變。此外，氧化鉿展現出高度的可微縮性、低熱預算算 (Thermal budget) 需求，以及與CMOS製程的良好相容性，使其成為新一代鐵電電晶體與鐵電記憶體的關鍵候選材料。
而目前，鐵電元件中的鐵電記憶體有了廣泛研究，最常見的結構為MFM（金屬-鐵電-金屬）配置，在Si基板上沉積金屬電極，中間則夾有鐵電層（HfZrOx, HZO）及界面層，此種結構通常採用TiN 做為金屬電極，而本文則探討氧化鉿鋯（HfZrOx, HZO）在不同金屬電極條件下的特性變化。通過調整金屬電極種類、介電層厚度及沉積方法和退火溫度等關鍵製程參數，觀察其元件特性，基於先前的研究，我正在通過實驗使用不同的金屬鈮（Nb）做為電極來探索及提高鐵電記憶體的性能。
此外， Nb的臨界溫度為10K，這也意味著Nb作為低溫元件的量測可行性更高。因此，在未來發展上，可藉由觀察MFM結構在超導條件下的約瑟夫森接面。而隨著鐵電記憶體在人工智慧運算中的應用越來越受到重視，超導電子學與鐵電性的結合也是未來可能的重要研究方向。透過 Nb 超導材料的應用，這將有助於未來超導電子元件的發展，甚至可能為量子計算技術提供新穎的材料選擇。

Since the discovery of ferroelectric properties in hafnium oxide (HfO₂) in 2011, the material has attracted widespread attention. Compared to traditional ferroelectric materials, HfO₂ can maintain stable ferroelectricity even at thicknesses as low as 10 nm, mainly due to its unique phase transition behavior. Additionally, HfO₂ exhibits excellent scalability, low thermal budget requirements, and strong compatibility with CMOS processes, making it a key candidate for next-generation ferroelectric transistors and ferroelectric memory devices.
Currently, ferroelectric memory has been extensively studied among ferroelectric devices. The most common structure is the MFM (metal–ferroelectric–metal) configuration, where metal electrodes are deposited on a silicon substrate with a ferroelectric layer (HfZrOx, HZO) and an interfacial layer in between. This structure typically uses titanium nitride (TiN) as the metal electrode. In this study, we investigate how the properties of hafnium-zirconium oxide (HfZrOx, HZO) vary under different metal electrode conditions. By adjusting key process parameters such as the type of metal electrode, dielectric layer thickness, deposition method, and annealing temperature, we aim to observe changes in device performance. Based on previous research, I am currently exploring and enhancing the performance of ferroelectric memory through experiments using niobium (Nb) as the electrode material.
Moreover, with a critical temperature of 10 K, Nb offers higher feasibility for low-temperature device measurements. This opens the possibility of observing Josephson junction behavior in MFM structures under superconducting conditions. As the application of ferroelectric memory in artificial intelligence computing continues to gain attention, the integration of superconducting electronics with ferroelectricity may become a significant research direction in the future.
The application of Nb as a superconducting material will contribute to the development of future superconducting electronic devices and may even offer novel material choices for quantum computing technologies.

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