在此實驗中，我們將研究鎳摻雜二氧化鈦薄膜在矽基板上的特性。我們會進行未摻雜與摻雜的二氧化鈦薄膜之物理特性、化學特性和電特性方面的量測與討論。 物理特性方面，由場放射掃描電子顯微鏡和X光繞射來看薄膜的厚度和結構。化學特性部分，由X射線光電子光譜學和傅立葉轉換紅外光譜儀來看薄膜的化學組成比和化學鍵結。電特性部份，由電壓-電流特性圖與電容-電壓特性圖來看薄膜的漏電流與電容值。為了改善電特性，我們將進行鎳摻雜二氧化鈦薄膜之氧氣、氮氣和笑氣下回火處理的研究。
為了進行摻雜，我們選用氯化鎳當做實驗中的摻雜溶液，以改善電特性方面。在700度中通笑氣回火處理下，未摻雜的二氧化鈦薄膜之介電常數為29；摻雜後的二氧化鈦薄膜之介電常數提升到94。

In this study, the characteristics of Nickel-doped LPD-TiO2 films on silicon substrate were investigated. In our experiment, we do some measurement about physical, chemical and electrical properties for undoped and Nickel-doped LPD-TiO2 films and discussed with them. The TiO2 film thickness was characterized by field emission scanning electron microscopy ( FE-SEM ), structure was characterized by X-ray diffraction (XRD), chemical properties was characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR) and electrical properties was characterized by leakage current: current-voltage (B1500A) and dielectric constant: capacitance-voltage (4980A). For the electrical property improvements, we investigated the Ni-doped LPD-TiO2 films by the post-anneal treatments in nitrogen, oxygen and nitrous oxide ambient.
For nickel doping, the nickel chloride was used as the doping solution and the electrical characteristics were improved. After thermal annealing in nitrous oxide at 700 oC, the dielectric constant of polycrystalline titanium oxide film is 29 and can be improved to 94 with nickel doping.

論文審定書.....................................................................................................................i
ACKNOWLEDGEMENT ii
摘 要 iii
ABSTRACT iv
CONTNETS v
LIST OF FIGURES viii
LIST OF TABLE xi
Chapter 1 1
Introduction 1
1-1 Developments in Gate Dielectric 1
1-2 Properties of TiO2 3
1-3 Comparison of Deposition Methods of TiO2 4
1-4 Advantages of Liquid Phase Deposition 5
1-5 Motivation of Doping Nickel 6
Chapter 2 12
Experiments 12
2-1 Deposition System 12
2-2 Cleaning of Substrate 13
2.3 Aluminum Metal Cleaning Processes 14
2-4 Preparation of Deposition Solution 14
(A) Preparation of (NH4)2TiF6 solution 15
(B) Preparation of boric acid solution 15
(C) Preparation of Nickel chloride solution 15
(D) Preparation of SiO2 saturated H2SiF6 solution 15
2-5 Film Deposition 16
2-5.1 LPD-TiO2 process 16
2-5.2 Ni-doped LPD-TiO2 process 16
2-5.3 SiO2 layer Process 17
2-6 Growth Mechanisms of LPD-TiO2 Films 18
2.7 Mechanisms of LPD-SiO2 Films 19
2-8 Improvements of Electrical Properties by Nickel Doping 20
2-9 Characteristics 20
2-9.1 Physical and Chemical Properties 21
(a) Thickness and Cross-Sectional Morphologies 21
(b) Surface Morphologies 21
(c) Structure 21
(d) Composition 21
2-9.2 Electrical Properties 22
(a) Structure for Electrical Measurement 22
(b) Current-Voltage (I-V) Measurement 22
(c) Capacitance-Voltage Measurement 23
Chapter 3 29
Results and Discussion 29
3-1 Undoped and Ni-doped LPD-TiO2 Film at 40 oC on Si Substrate 29
3-1.1 Deposition Rate of LPD-TiO2 Films as a Function of Deposition Time 30
3-1.2 Deposition Rate of Ni-doped LPD-TiO2 Films as a Function of Deposition Time 30
3-2 XRD Patterns of Undoped and Ni-doped LPD-TiO2 Films by Thermal Treatment 31
3-2.1 X-ray Diffraction Spectra of LPD-TiO2 Films by N2O Annealing 31
3-2.2 X-ray Diffraction Spectra of LPD-TiO2 Films by O2 Annealing 31
3-2.3 X-ray Diffraction Spectra of LPD-TiO2 Films by N2 Annealing 32
3-2.4 X-ray Diffraction Spectra of Ni-doped LPD-TiO2 Films by N2O Annealing 32
3-2.5 X-ray Diffraction Spectra of Ni-doped LPD-TiO2 Films by O2 Annealing 33
3-2.6 X-ray Diffraction Spectra of Ni-doped LPD-TiO2 Films by N2 Annealing 34
3-3 FTIR Spectra of Undoped and Ni-doped LPD-TiO2 Films by Thermal Treatment 34
3-3.1 FTIR Spectra of Undoped LPD-TiO2 Films by N2O Annealing 34
3-3.2 FTIR Spectra of Undoped LPD-TiO2 Films by O2 Annealing 35
3-3.3 FTIR Spectra of Undoped LPD-TiO2 Films by N2 Annealing 36
3-3.4 FTIR Spectra of Ni-doped LPD-TiO2 Films by N2O Annealing 36
3-3.5 FTIR Spectra of Ni-doped LPD-TiO2 Films by O2 Annealing 37
3-3.6 FTIR Spectra of Ni-doped LPD-TiO2 Films by N2 Annealing 37
3-4 ESCA Analysis of Ni-doped LPD-TiO2 Films 38
3-5 Electrical Characteristics of LPD-TiO2 Films by Thermal Treatment 38
3-5.1 Electrical Characteristics of LPD-TiO2 Films by N2O Annealing 38
3-5.2 Electrical Characteristics of LPD-TiO2 Films by O2 Annealing 40
3-5.3 Electrical Characteristics of LPD-TiO2 Films by N2 Annealing 41
3-6 Electrical Characteristics of Nickel-doped LPD-TiO2 Films Prepared by Thermal Treatment 42
3-6.1 Electrical Characteristics of Nickel-doped LPD-TiO2 Films by N2O Annealing 42
3-6.2 Electrical Characteristics of Nickel-doped LPD-TiO2 Films by O2 Annealing 43
3-6.3 Electrical Characteristics of Nickel-doped LPD-TiO2 Films by N2 Annealing 45
3-7 Various NiCl2 Volumes of Nickel-doped LPD-TiO2 Film at 40oC on Si Substrate 46
3-7.1 The Thickness of Ni-doped TiO2 Films on Si substrate as a function of Various NiCl2 Volumes 46
3-7.2 Electrical Characteristics of Various NiCl2 Volumes Ni-doped TiO2 Films Annealed at 700 oC in N2O Ambient 46
3-8 Improvement of J-E Characteristics of Ni-doped LPD-TiO2 on Si with a SiO2 Layer 47
Chapter 4 89
Conclusions 89
References 90
Chapter 1 90
Chapter 2 98
Chapter 3 99

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