近年來，半導體材料中的矽、鍺的量子點被認為可以與現今的半導體製程技術相配合。而量子的尺寸效應及可見光範圍的光致螢光(PL)也已經被發現在奈米尺寸的矽或是鍺量子點中。因此，在半導體的領域中量子尺寸縮小的效應主要可以應用在快閃記憶體及光電的元件上。在光電元件的應用方面，利用其量子點周圍的高能障形成量子侷限效應所產生的能階分裂或是利用一些界面態與量子點來形成其發光的機制；而在快閃記憶體的應用上，則是以量子點浮動閘極取代傳統的複晶矽浮動閘極。主要的優點有密集度增加、可設計的能階差、降低讀寫的電壓、增快讀寫的速度、以及記憶體中載子儲存時間的加長。基於以上種種的優點都傾向利用量子點來製作光電及記憶體元件。本論文主要以鍺量子點的記憶體作為主要的研究，利用電漿輔助化學氣相沉積(PECVD)的方式及不同的退火條件析出鍺量子點，且以材料的研究以及電性的佐證來研究鍺量子點的電荷儲存效應。

Over the past years, semiconductor quantum crystallite or micro-crystals of Si and Ge have received considerable attention for both fundamental and technological reasons. Quantum size effect and visible photoluminescence have been observed in nanometer-sized Si or Ge quantum crystallites. It has two practical applications. one is to prove to be optical semiconductor devices；the other is to turn into nano-crystal memories.
The material Ge is considered a promising material for optical device fabrication. It has been found that Ge quantum dots embedded in Si matrices exhibit photoluminescence (PL) originating from the spatially indirect no-phonon recombination between holes confined within the Ge dots and electrons from the conduction band of the Si. For nano-crystal memories employing discrete charge traps as storage elements have exhibited great potential in device performance, power consumption, and technology scalability, thus recently attracting much research attention as promising candidates to replace the conventional DRAM or Flash memories.
In the thesis, we will discuss the material properties of SiNGe and SiCNGe films, such as FTIR, AES, Raman Scattering spectrum analysis. The write/erase and retention characteristics of the nano-crystal are presented through current–voltage (I–V) and capacitance–voltage (C–V) measurements.

Contents

Abstract (Chinese) ……………………..………………………….……i
Abstract (English) …………………………………………………….ii
Acknowledgment (Chinese) …………………………………….……iv
Content ………………………………………………….………………v
Table Captions……………………………………………………………viii
Figure Captions ……………………………………………………...ix

Chapter.1 Introduction
1.1 General Background……………………..……………….1
1.2 Motivation …………………………………………………….4
1.3 Organization of This Thesis……………………………5

Chapter.2 Intrinsic characteristics of the SiNGe and SiCNGe
Deposited by PECVD Method
2.1 Introduction………………………………………...............6
2.2 Experimental Procedure…………………………………….7
2.3 Results and discussion………………………………...……8
2.3.1 Intrinsic Film Properties……………………………...8
2.3.2 Electrical Characterization of the Intrinsic Film…9
2.4 Summary…………………………………………………10




Chapter.3 Characterization of the SiNGe thin Film with Various Thermal-Annealing Treatment
3.1 Introduction.…………………………………………….11
3.2 Experimental Procedure…………………………………...12
3.3 Results and discussion…………………………………….12
3.3.1 Structure Change after N2 800oC Thermal ………12
Annealing
3.3.2 Electrical Characteristics Measurement after…....14
N2 800oC Thermal-Annealing
3.3.3 Structure Change After O2 800oC Thermal……….16
Annealing
3.3.4 Electrical Characteristics Measurement after O2..17
800oCThermal-Annealing
3.3.5 Electrical Characteristics and Material …………...19
Measurement After O2 1000oC Thermal-Annealing
3.4 Summary…………………………………………………….21

Chapter.4 Characterization of the SiCNGe thin Film with Various Thermal-Annealing Treatment
4.1 Introduction.………………………………………………. 23
4.2 Experimental Procedure…………………………………...25
4.3 Results and discussion…………………………………….26

4.3.1 Structure Change After N2 800oC Thermal ………26
Annealing
4.3.2 Electrical Characteristics Measurement after……27
N2 800oC Thermal-Annealing
4.3.3 Structure Change After O2 800oC Thermal……….28
Annealing
4.3.4 Electrical Characteristics Measurement After..29
O2 800oC Thermal-Annealing
4.3.5 Electrical Characteristics and Material……………30
Measurement After O2 1000oC Thermal-Annealing
4.4 Summary……………………………………………………33

Chapter.5 Conclusion and suggestion for future work
5.1Conclusion……………………………………………….....34
5.2 Suggestion of Future Work ……………….…………..…37

References…………………...…..………………………………………38

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