近幾年來，具有奈米點儲存單元的非揮發性記憶體元件被廣泛的提出來克服傳統浮動閘極記憶體在操作上及可靠度上的問題。良好的記憶體元件需要具備好的元件耐力，保存時間長及操作電壓小等特性。在眾多奈米點記憶體元件中，金屬奈米點的記憶體受到廣泛的研究而有機會成為新一代記憶體元件結構。金屬點的特色主要有高狀態密度、強通道耦合能力、可調變金屬功函數以及不易受載子侷限效應所引起的能階擾動。在元件設計上金屬奈米點不但可減少操作電壓、增加抹除寫入速度與電子保存時間，最重要的是我們可以控制奈米點尺寸以及低溫製作。此項優點能應用於薄膜電晶體液晶顯示器上，如面板上製作驅動IC與邏輯IC可以增加面板多變性，開關電晶體旁增加影像儲存記憶體來節省電源損耗以增加可攜帶性。本論文主要以高功函數金屬作為記憶體儲存元件為研究，利用高溫氧化、低溫氧氣退火條件形成奈米點，並用材料分析與電性分析來研究奈米點的電荷儲存效應。

In recently years, nonvolatile memory with nanocrystals cell have widely applied to overcome the issue of operation and reliability for conventional floating gate memory. The excellent electrical characteristics of memory device need good endurance, long retention time and small operation voltage. Among numerous memory devices with nanocrystals, the memory device with metal nanocrystals was widely researched. It will be new candidate for flash memory. The advantages of metal nanocrystals has have higher density of states around Fermi level, stronger coupling with conduction channel, wide range of available work functions and smaller energy perturbation due to carrier confinement. So metal nanocrystals can reduce operate voltage, and increase write/erase speed and endurance. Most important of all, we can control the sizes of nanocrystals dot and manufacture at low temperature。This advantage can apply to thin film transistor liquid crystal display; it fabricates driving IC and logical IC on panel for diverseness and adds memory beside switch TFT as image storage to reduce power consumption for portability.
In this thesis, we will discuss metal nanocrystals as memory storage medium. And we can use high temperature oxidation, low temperature annealing with oxygen to form nanocrystals. Besides we analyze the effect of electron storage at metal nanocrystals by means of material and electrical analysis.

Contents

Abstract (Chinese) …………………………………………………i
Abstract (English) …………………………………………………ii
Acknowledgment (Chinese) …………………………………………iv
Content…………………………………………………………………v
Figure Captions ……………………………………………………Vii

Chapter.1 Introduction
1.1 General Background………………………………………………1
1.2 Motivation ………………………………………………………6
1.3 Organization of This Thesis…………………………………8

Chapter.2 Characteristic of Nickel-Silicide Nanocrystals Formed with Various Oxidation Temperatures
2.1 Introduction………………………………………………………9
2.2 Experimental Process…………………………………………11
2.3 Results and discussion………………………………………12
2.3.1 Material Characteristic after 900℃ oxidation…12
2.3.2 Electrical Characteristic after 900℃ oxidation…12
2.3.3 Material Characteristic after 800℃ oxidation……14
2.3.4 Electrical Characteristic after 800℃ oxidation…14
2.3.5 Electrical Characteristic after 700℃ oxidation…15
2.4 Summary……………………………………………………………16

Chapter.3 Characteristic of Metal Nanocrystals Formed with Various Thermal Annealing Treatments
3.1 Introduction……………………………………………………17
3.2 Experimental Process…………………………………………18
3.3 Results and discussion………………………………………19
3.3.1Electrical characteristic with O2 400℃ annealing…19
3.3.2Electrical characteristic with O2 600℃ annealing…20
3.4 Summary……………………………………………………………21

Chapter.4 Conclusion and suggestion for future work
5.1Conclusion…………………………………………………………22
5.2 Suggestion of Future Work …………………………………23

References……………………………………………………………24

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