相較於其他非揮發性記憶體，鐵電記憶體實現一個電晶體作為記憶體元件，可以減少所需的元件讓製程較簡易。二氧化鉿基底的鐵電材料與傳統鐵電材料相比具有相容於先進CMOS製程、高切換速度及低功率消耗等特性，歸功於鐵電材料的極化特性能隨著外加電場的正負極變化改變極化狀態。但也因此，可靠度更容易受到鐵電氧化層和矽基板間介面層影響，所以在介面層材料的選擇需更加嚴謹，考量各種適性，如:介電常數、與矽基板間的能隙大小、熱穩定性、是否助於鐵電性等等。
本論文中主要利用氮氧化鋁(AlON)作為介面層來實現以HfZrOx (FE-HZO)為氧化層的鐵電電晶體(FeFET)應用於鐵電記憶體，在不破壞鐵電相穩定的情況下，含氮量約為13％的高介電常數材料-氮氧化鋁，被選擇作為鐵電電晶體中氧化層和矽基板之間的介面層（IL）內存以增強記憶視窗（memory window），與以二氧化矽(SiO2)作為介面層的鐵電電晶體相比，增強了可靠度。
氮氧化鋁作為介面層的鐵電電晶體顯示優良的性能，通過 ±4V的操作電壓下記憶視窗可以達到3.1 V，可保持長達十年的使用壽命，並且在長脈衝寬度為10-4 s操作下高達105次的耐用性，較其它鐵電電晶體出色。歸因於介面層較高的介電常數值和較大的ΔEv，使得較小的壓降跨在介面層上同時抑制電荷捕捉(charge trapping)效應。含氮的介面層還增強了熱穩定性和通過限制殘留的OH基與矽基板反應抑制新的介面層產生。此外，氮氧化鋁和鐵電層可以在原子層沉積步驟中不破腔進行簡化了製程。從元件性能和製程觀點上，氮氧化鋁實現更可行的鐵電記憶體的途徑。

Compared with traditional ferroelectric materials, the hafnium oxide based ferroelectric materials are compatible with advanced CMOS processes, high switching speed and low power consumption. The polarization characteristics of the ferroelectric materials are attributed to the difference of the applied electric field which changes the polarization state. Compared with other non-volatile memory, ferroelectric memory transistors implement a transistor as a memory element, which can reduce the required components and make the process easier. But because of this, reliability is more easily affected by the interface layer between the ferroelectric oxide layer and the silicon substrate, so the choice of the interface layer material needs to be more rigorous, and various suitability needs to be considered.
In this paper, aluminum oxynitride (AlON) is mainly used as the interface layer to realize the application of ferroelectric thin film transistors (FE-FET) with HfZrOx (FE-HZO) as the oxide layer to ferroelectric memory applications.Without destabilizing the ferroelectric (FE) phase, high-k AlON with [N] of ~13 % was proposed as the interfacial layer (IL) between FE HfZrOx (HZO) and Si substrate for FeFET memory to enhance the memory window (MW) while improving reliability compared to SiO2 IL. The AlON-based memory shows promising performance in terms of a large MW of 3.1 V by ±4 V operation, long retention up to 10 years, and robust endurance up to 105 cycles with a long pulse width of 10-4 s, outstanding other FeFET memory devices. It is ascribed to the high k value and larger ΔEv that respectively allow a lower voltage drop across the IL and suppress hole trapping. [N] in the IL also enhances the thermal stability that inhibits sub-IL formation by restraining the reaction of residual OH groups with Si substrate. Besides, the AlON and FE-HZO can be integratedin a single ALD step to simplify the process. From device performance and process viewpoints, AlON paves a promising avenue to enable more reliable and feasible FeFET memory.

摘要 i
Abstract ii
誌謝 iv
目錄 v
圖目錄 vii
表目錄 x
第一章 序論 1
1-1 研究背景 1
1-2 鐵電材料 2
1-2-1 材料結構劃分 2
1-2-2 傳統鐵電材料V. S新穎鐵電材料 2
1-2-3 鐵電性 4
1-3 鐵電電晶體介紹 6
1-4 介面層介紹 7
第二章 文獻回顧 19
2-1 鐵電材料選用與分析 19
2-1-1 鐵電材料HfZrOx與HfSiOx的選擇 19
2-1-2 非理想鐵電特性曲線介紹 20
2-2 鐵電電晶體的瓶頸 21
2-2-1 記憶視窗失效機制 21
2-2-2 鐵電電晶體記憶時間保持失效原因 22
2-2-3 鐵電電晶體耐用度失效機制 23
2-3 介面材料選用及分析 25
2-3-1 氧化鋁作為絕緣層優點 25
2-3-2 氧化鋁對於鐵電性缺點 25
第三章 實驗動機以及製程步驟 39
3-1 實驗動機 39
3-2 實驗製程步驟 40
第四章 實驗結果與討論 49
4-1 鐵電電晶體電性分析 49
4-1-1 電晶體電壓電流特性分析 49
4-1-2 不同量測手法之電荷捕捉效應 50
4-1-3 元件可靠度分析之耐用度 50
4-1-4 元件可靠度分析之記憶保持時間 52
4-1-5 利用Pulse I-V方法萃取PUND 53
4-2 鐵電電晶體物性分析 53
4-2-1 XPS(X-ray photoelectron spectroscopy)分析 53
4-2-2 TEM(transmission electron microscope)分析 54
4-2-3 Mapping分析 54
4-2-4 XRD(X-ray diffractometer)分析 55
第五章 結論與未來展望 68
Reference 70
Chapter 1 70
Chapter 2 71
Chapter 3 72
Chapter 4 73
Chapter 5 73

Chapter 1
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Chapter 2
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Chapter 3
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Chapter 4
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Chapter 5
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