臺灣博碩士論文加值系統

根據ITRS的預測，閘極氧化層的漏電流效應會因為直接穿透效應的因素而變大，不但使元件壽命降低，也會造成不必要的功率損秏。隨著元件微縮，想要元件仍然有好的電性，取代傳統的二氧化矽是必要的。為了解決這些問題，我們使用高介電質材料取代之，像三氧化二鉿，三氧化二釓，三氧化二鑭，三氧化二釔，三氧化二釹…等。我們對高介電質材料的要求有好的熱穩定性、製程整合與金屬閘極的相容性、大的能階差。
本篇論文探討利用濺鍍方式來沉積三氧化二釔與三氧化二釹的電性及物理特性。此外，我們也利用NH3電漿的方式，探討它對三氧化二釔薄膜的影響。我們發現經由NH3電漿處理後能抑制interfacial layer的長成也能改善電性，如提高崩潰的電場和降低漏電流等。最後，我們使用多種氬氣比氧氣流量比例沉積薄膜，找出最合適的沉積比例。經由實驗後，我們發現對三氧化二釔薄膜而言，以氬氣:氧氣為25:5為最好。另外就三氧化二釹薄膜而言，以氬氣:氧氣為12.5:12.5為最佳。以此條件沉積出來的薄膜，都有較薄的厚度，較低的漏電流與較高的崩潰電壓。

In this work, the yttrium oxide and neodymium oxide film were deposited on Si substrate by RF-sputtering. We investigated the influence of NH3 plasma on yttrium oxide film. It is found that the breakdown electrical field and gate leakage were improved by NH3 plasma treatment. Therefore, it suppresses the formation of the interfacial layer and silicate. In addition, we study the influence of Ar:O2 ratios to optimize the Y2O3 sputtering condition. We found that the optimize sputtering gas conditions for Y2O3 thin film is Ar:O2=25:5. This condition exhibits thinner thickness, lower gate leakage current, and higher breakdown voltage. The film (Ar:O2=25:5) is more comparability with Y2O3 component structure. The surface morphology of the yttrium oxide films, RMS decreases with R (O2/Ar) decreases. Also, we study the influence of Ar:O2 ratios to optimize the Nd2O3 sputtering condition. Optimize PDA temperature for Nd2O3 thin films is 600˚C. From the C-V curve, we found that the condition (Ar:O2=12.5:12.5) has thinner Nd2O3 film thickness.

Acknowledgment i
Chinese Abstract ii
English Abstract iii
Contents iv
Content of Figures vii
List of Tables x
Chapter 1 Introduction
1-1 CMOS technology scaling trends…………………………1
1-2 The limit of gate oxide scale……..……………………2
1-3 High-k condidates…………………...……………………2
1-4 Stability of high-k dielectric layer...……………………2
1-5 Issues for interface engineering…...……………………3
1-6 The motivation in this study………...……………………3
1-7 Thesis Organization…………………...……………………4

Chapter 2 The Physical Properties of Yttrium Oxide
2-1 Introduction…………………………………………….……...6
2-2 Experiment…………………………………….……………..7
2-3 Results and Discussion………………….…………………….7
2-3-1 XRD of yttrium oxide film analysis……………………7
2.3.2 XPS of yttrium oxide film analysis….………………...7
2-4 Summary……………………………………….……………….8
Chapter 3 The Electrical Characteristic of Yttrium Oxide Film MOSCAP
3-1 Introduction……………………………………….…….13
3-2 Experiment………………………………………….…………13
3-3 Results and Discussion………………………….……………...13
3-3-1 Basic yttrium oxide thin film MOSCAP characteristic….14
3-3-2 NH3 plasma pre-treatment effect on yttrium oxide thin film MOSCAP…………………………………...……………16
3-4 Summary……………………………………………….…….27
Chapter 4 The Electrical Characteristics and Physical Properties of O2/Ar Sputter Ratio on Yttrium Oxide Films
4-1 Introduction…………………………………………….……...30
4-2 Experiment…………………………………….……………..30
4-3 Results and Discussion………………………..…..………….31
4-3-1 XPS of yttrium oxide film for different gas ratio analysis……………………………………...…………..31
4-3-2AFM of yttrium oxide film for different gas ratio analysis………………………………..…………….…..32
4-3-3 C-V and J-V characteristics of MOSCAP with yttrium oxide gate dielectric using various Ar/O2 ratio................32
4-4 Summary……………………………………….……………….34
Chapter 5 The Electrical Characteristics and Physical Properties of O2/Ar Sputter Ratio on Neodymium Oxide Films
5-1 Introduction…………………………………………….……...53
5-2 Experiment…………………………………….……………..53
5-3 Results and Discussion………………………..…..………….54
5-3-1 C-V and J-V characteristics of MOSCAP with neodymium oxide gate dielectric using various Ar/O2 ratio……………………………………………...............54
5-4 Summary……………………………………….……………….55
Chapter 6 Conclusions and Future Works
6-1 Conclusions…………………………………….……………63
6-2 Future works…………….…………………………………63

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