臺灣博碩士論文加值系統

使用高介電值材料在薄膜電晶體上，可以提高閘極氧化層電容值，以獲得一個較高的開口率及汲極電流；同時需要使用低介電值材料用於各導線連接處來降低電阻-電容延遲。在本實驗中，主要採用液相沈積法來成長氧化鈦薄膜在非晶矽及多晶矽上，用來獲得一個11.76和29.54的高介電值薄膜。

When the size of display panel increased, the RC delay of TFTs became serious. High dielectric (high-k) materials used as the gate oxide can increase the gate oxide capacitance Co, which can induce a higher drain current, and higher aperture ratio. Therefore, low-k materials are used for inter-metal dielectrics. Thus, it can improve the RC delay.
LPD-TiO2 film on a-Si and poly-Si technology and characterization of films were described in detail in this thesis. The highest dielectric constant of 11.76 and 29.54, and lowest leakage current density of 5.45×10-7A/cm2 at -0.45 MV/cm and 3.11×10-1 A/cm2 at 0.45 MV/cm for the O2-annealed of LPD-TiO2film on a-Si and poly-Si can be obtained.

CONTENTS
CHAPTER 1 1
Introduction 1
1-1 Background 1
1-1.1 Advantages of Active Matrix Display Liquid Crystal Display (AMLCD) 1
1-1.2 Structure of AMLCD 1
1-1.3 Comparison a-Si and poly-Si TFTs 3
1-2 Motivation 4
1-3 Properties of TiO2 5
1-4 Advantages of Liquid Phase Deposition 6
CHAPTER 2 13
EXPERIMENT 13
2-2 Deposition procedures 14
2-2.1 Cleaning of Substrate 14
2-2.2 Preparation of deposition solution 15
2-2.3 LPD-TiO2 Processes 16
2-2.4 SiO2 buffer layer Processes 17
2-3 Annealing Treatment 18
2-4 Characteristics 18
2-4.1 Physical Property 18
2-4.2 Chemical property 19
2-4.3 Electrical Properties 19
CHAPTER 3 24
RESULTS AND DISCUSSION 24
Part A: LPD-TiO2 films deposited on a-Si/P-Si and poly-Si/P-Si by (NH4)2TiF6 solution 24
3-1 Mechanism of LPD-TiO2 film 24
3-2 LPD-TiO2 deposited on a-Si/P-Si 25
3-2-1 Physical Characteristics 25
3-2-2 Chemical Characteristics 27
3-2-3 Electrical Characteristics 29
3-3 LPD-TiO2 deposited on poly-Si 34
3-3-1 Physical Characteristics 34
3-3-2 Chemical Characteristic 35
3-3-3 Electrical Characteristics 37
Part B: LPD-TiO2 films deposited on a-Si/P-Si and poly-Si/P-Si by H2TiF6 solution 40
3-4 Mechanism of LPD-TiO2 film 40
3-5 LPD- TiO2 deposited on a-Si 40
3-5-1 Physical Characteristics 41
3-5-2 Chemical Characteristics 42
3-5-3 Electrical Characteristics 42
3-6 LPD- TiO2 deposited on poly-Si 45
3-6-1 Physical Characteristics 45
3-6-2 Chemical Characteristics 46
3-6-3 Electrical Characteristics 47
CHAPTER 4 85

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