臺灣博碩士論文加值系統

近年來，光電產業蓬勃發展，全球液晶面板業目前最熱門的話題即是IGZO技術應用在最先進液晶顯示器製品，因此驅動顯示器的開關元件「薄膜電晶體」（ＴＦＴ）就顯得格外重要。由於薄膜電晶體的好壞將會大幅的影響顯示器的性能，因此如何改善薄膜電晶體的品質、以及降低生產成本，一直都是研究與生產上努力的目標。
本論文採用射頻磁控濺鍍法來製備氧化銦鎵鋅薄膜，第一部分:以GIXRD之材料分析手法探討不同UV-Ozone照光時間應用於GZO透明導電薄膜其常溫與變溫之電特性變化。第二部份：採用三種不同退火溫度作為對薄膜的處理並以XPS、AFM、以及Contact Angle等儀器分析薄膜之材料特性與觀察薄膜之微結構。第三部分:經由一系列的分析，成功製備出高飽和場效載子遷移率為9.61 cm2/Vs，高開關比Ion/Ioff ~107，最佳次臨界擺幅S.S=0.29V/decade 之電晶體。
最後，根據最佳的退火溫度參數，將元件穩定性以變溫量測(NBTS)以及薄膜電晶體之磁滯效應(Hysteresis)加以討論。

In recent years, the optoelectronics industry has well developed. The IGZO technology used in the cutting-edge display products has been the currently hottest topic in global LCD display industry, in this way the driving device of the LCD display - thin film transistor (TFT) is particularly important. The quality of TFTs will dramatically affect the performance of the LCD display, so how to improve the quality of thin-film transistors, as well as lower production cost, has been the goal of the research and production efforts.
In this study, we use rf magnetron sputtering method to fabricate GaZnO transparent conductive oxide and InGaZnO thin-film transistors. First Part: The Investigation of the GaZnO TCO Film Hall measurement in Room-Temp ＆ Temp-Dependent two conditions through GIXRD technique. Second Part: We use XPS, AFM, and Contact Angle technique to identify the relationship between InGaZnO thin-film transistors with various annealing temperature. Third Part: We also examine the InGaZnO TFT devices characteristic and stability via Negative Bias Temperature Stability (NBTS) and hysteresis.

摘要 I
ABSTRACT II
致謝 III
TABLE OF CONTENTS IV
LIST OF TABLES VI
LIST OF FIGURES VII
CHAPTER 1 INTRODUCTION 1
1.1 PREFACE 1
1.2 MOTIVATION 1
1.3 ORGANIZATION OF THIS THESIS 2
CHAPTER 2 THEORY AND LITERATURE REVIEW 4
2.1 ZINC OXIDE 4
2.2 OVERVIEW OF TRANSPARENT CONDUCTIVE OXIDE 6
2.3 OVERVIEW OF THIN FILM TRANSISTOR 8
2.4 BASIC OPERATION OF THIN FILM TRANSISTOR 12
2.5 THIN-FILM TRANSISTOR CHARACTERISTIC PARAMETERS 15
2.6 PHYSICS VAPOR DEPOSITION SYSTEM 18
2.6.1 Physics Vapor Deposition Method 18
2.6.2 RF magnetron sputtering 19
2.6.3 The principle of R.F magnetron sputtering 19
CHAPTER 3 EXPERIMENTS AND MEASUREMENT TECHNIQUES 21
3.1 EXPERIMENTAL METHODS 21
3.1.1 GaZnO TCO thin-films fabrication Process 21
3.1.2 TFT Device fabrication Process 22
3.2 CHARACTERIZATION FOR MATERIALS AND DEVICES 24
3.2.1 X-ray photoelectron spectroscopy (XPS) 24
3.2.2 X-ray diffraction spectroscopy 25
3.2.3 UV transmittance and absorption 25
3.2.4 Atomic force microscope(AFM) 26
3.2.5 Surface Energy 27
3.2.6 Measurement of GaZnO TCO characteristics 27
3.2.7 Measurement of InGaZnO TFT characteristics 29
CHAPTER 4 RESULTS AND DISCUSSIONS 30
4.1 THE INVESTIGATION OF THE ZNO:GA TCO FILM SCATTERING MECHANISM 30
4.2 BASIC IGZO TFT DEVICE ELECTRICAL PROPERTIES 42
4.3 MATERIAL ANALYSIS OF IGZO THIN-FILMS 43
4.3.1 XPS spectra of Annealing treated IGZO films 43
4.3.2 Contact Angle 48
4.3.3 AFM 50
4.4 THE ELECTRICAL PROPERTIES OF A-IGZO TFT WITH VARIOUS ANNEALING TEMPERATURE 54
4.5 NEGATIVE BIAS TEMPERATURE STABILITY OF IGZO TFT 56
CHAPTER 5 CONCLUSIONS AND SUGGESTIONS 64
5.1 CONCLUSIONS 64
5.2 FUTURE WORK 64
REFERENCE 66

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