指導教授：胡振國臺灣大學：電子工程學研究所林建智Lin, Chien-ChihChien-ChihLin2014-11-302018-07-102014-11-302018-07-102014http://ntur.lib.ntu.edu.tw//handle/246246/263833With the aggressive downscaling of MOS devices in semiconductor industry, the high-k gate dielectrics continuously play significant roles to achieve small equivalent oxide thickness for high-performance logic technology. The low manufacturing cost and low-temperature process of high-k dielectrics are also of practical interests for display and solar cell industry. In this dissertation, the Al2O3 MOS devices using room-temperature sputtering followed HNO3 compensation technique were demonstrated. After HNO3 compensation, the surface roughness, interface trap density, flatband voltage, and leakage current would also be effectively improved. The better reliability performance was also observed in dielectric breakdown tests and ten-year lifetime projections. Moreover, the positive bias current of Al2O3 MOS devices without HNO3 compensation showed the irregular temperature response at temperature above 70 ℃, which is corresponding to Frenkel-Poole emission. In contrast, the generation-recombination current is the dominant component for the Al2O3 MOS devices with HNO3 compensation. Using the temperature-sensitive current characteristics, we successfully demonstrated the Al2O3 MOS tunneling temperature sensors with enhanced temperature sensitivity and improved power consumption in comparison with SiO2 and HfO2 sensors. Subsequently, the electrical nonuniformity of ultrathin SiO2 and HfO2 gate dielectrics was investigated. The effective uniform area ratio regarded as an indication of gate oxide quality can be extracted from the deep depletion of C-V characteristics. In our cases, the effective uniform area ratio increases with SiO2 thickness, whereas decreases with increasing equivalent oxide thickness of HfO2, which was also reconfirmed by the same trend of leakage current fluctuations and the constant field stress measurements. Furthermore, a particular edge-dependent inversion current behavior resulting from edge fringing effect was observed for MOS tunneling diodes. The inversion current would increase with increasing tooth spacing for comb-shaped MOS tunneling diodes. The results suggested that the current conduction would be controlled by the electron diffusion current between the teeth and hole tunneling current affected by Schottky barrier height lowering. Finally, the photosensitivity can be improved by reducing SiO2 thickness and selecting smaller tooth spacing for SiO2 comb-shaped MOS tunneling photodiodes. In addition, the HfO2 photodiodes demonstrated high and steady photosensitivity owing to the current conduction dominated by electron only and smaller conduction band offset. In appendix of this dissertation, the electrical transport and photoconductive characteristics of CdTe nanowire transistors were investigated, which cooperated with the NANI group in University of Southern California. The Sb doped CdTe nanowire transistors exhibited p-type conductivity. Two acceptor levels existing in energy bandgap of CdTe nanowire were found via low-temperature electrical measurements, which is exactly in agreement with the photoluminescence measurement results. In addition, the Sb doped CdTe nanowire transistors demonstrated significant photoresponse to visible-near-infrared irradiation.Contents Abstract (Chinese) I Abstract (English) III Contents V List of Figure Captions XI List of Table Captions XIX Chapter 1 Introduction 1-1 Motivation 1 1-2 High-k Gate Dielectrics 5 1-3 Interface Issues in Advanced MOS Devices 7 1-4 Gate Oxide Reliability of MOS Devices 8 1-5 MOS Tunneling Temperature Sensors 9 1-6 MOS Tunneling Photodiodes 10 1-7 Thesis Overview 11 Chapter 2 Improvement in Physical and Electrical Characteristics of Low-Temperature Processing Al2O3 High-k Dielectrics Utilizing Nitric Acid Compensation Method 2-1 Introduction 17 2-2 Experimental Details 19 2-2-1 Fabrication of Al2O3 MOS Capacitors 19 2-2-2 Measurement Details 21 2-3 Physical Properties of Al2O3 High-k Dielectrics 21 2-3-1 Surface Topography of Al2O3 High-k Dielectrics 21 2-3-2 Microstructure and Elemental Analysis of Al2O3 MOS Capacitors 22 2-4 Electrical Properties of Al2O3 MOS Capacitors 23 2-4-1 Capacitance-Voltage Characteristics 23 2-4-2 Interface Properties 25 2-4-3 Current-Voltage Characteristics 26 2-4-4 Comprehensive Discussion of Electrical Characteristics 27 2-5 Summary 28 Chapter 3 Nitric Acid Compensated Al2O3 MOS Devices with Improved Negative Bias Reliability and Positive Bias Temperature Response 3-1 Introduction 41 3-2 Experimental Details 43 3-2-1 Fabrication of Al2O3 MOS Capacitors 43 3-2-2 Measurement Details 44 3-3 Comparison of Room-Temperature Reliability Performance for Al2O3 MOS Devices without and with Nitric Acid Compensation 44 3-3-1 Time-Zero Dielectric Breakdown Measurements 44 3-3-2 Time-Dependent Dielectric Breakdown CVS Measurements 46 3-3-3 Time-Dependent Dielectric Breakdown CCS Measurements 48 3-3-4 Illustration of Dielectric Breakdown Mechanism 50 3-4 Temperature-Dependent Negative Bias Reliability Analysis 52 3-4-1 Temperature-Dependent CVS Measurements 52 3-4-2 Ten-Year Lifetime Projection 53 3-5 Improvement of Positive Bias Temperature Response 54 3-5-1 Temperature-Dependent Current Conduction Behaviors 54 3-5-2 Fundamental Current Conduction Mechanism 55 3-5-3 Illustration of Current Instability (Higher Temperature Response) 58 3-6 Summary 61 Chapter 4 Performance Enhancement of MOS Tunneling Temperature Sensors by Employing Ultrathin Al2O3 High-k Dielectrics 4-1 Introduction 75 4-2 Experimental Details 77 4-2-1 Fabrication of MOS Tunneling Temperature Sensors 77 4-2-2 Measurement Details 79 4-3 Working Principle and Design Concept 80 4-3-1 Current Conduction Mechanism and Working Principle 80 4-3-2 Design Concept Description 82 4-4 Characterization of Al2O3 MOS Tunneling Temperature Sensors 84 4-4-1 Temperature-Sensitive Characteristics 84 4-4-2 Investigation of Dominant Current Conduction Mechanism 85 4-4-3 Cycling Reliability Performance 87 4-5 Comparison of SiO2, HfO2 and Al2O3 MOS tunneling Temperature Sensors 88 4-5-1 Enhanced Temperature Sensitivity by Employing Al2O3 Dielectrics 88 4-5-2 Saturation Voltage Improvement by Employing Al2O3 Dielectrics 89 4-5-3 Comprehensive Discussion of Three Kinds of Temperature Sensors.91 4-6 Summary 92 Chapter 5 Electrical Nonuniformity Phenomenon in Deep Depletion Capacitance-Voltage Behavior of MOS Capacitors with Ultrathin SiO2 and High-k Dielectrics 5-1 Introduction 105 5-2 Experimental Details 107 5-2-1 Fabrication of MOS Capacitors with SiO2 and HfO2 Dielectrics 107 5-2-2 Measurement Details 107 5-3 Deep Depletion Behaviors of Capacitance-Voltage Characteristics for MOS Capacitors with Ultrathin Oxides 108 5-3-1 Brief of Deep Depletion Behaviors in MOS Devices 108 5-3-2 Different Deep Depletion Behaviors of MOS Capacitors with SiO2 and HfO2 High-k dielectrics 109 5-4 Concept of Local Depletion Capacitance and Effective Uniform Area Ratio 5-4-1 Concept of Local Depletion Capacitance 110 5-4-2 Concept of Effective Uniform Area Ratio 112 5-5 Investigation of Electrical Nonuniformity in Ultrathin SiO2 and HfO2 High-k Dielectrics 116 5-5-1 Comparison of Electrical Nonuniformity in Ultrathin SiO2 and HfO2 High-k Dielectrics 116 5-5-2 Connection between Leakage Current and Electrical Nonuniformity 117 5-5-3 Relationship between Reliability and Electrical Nonuniformity 118 5-6 Summary 119 Chapter 6 Investigation on Edge Fringing Effect and Oxide Thickness Dependence of Inversion Current in MOS Tunneling Diodes with Comb-Shaped Electrodes 6-1 Introduction 131 6-2 Experimental and Design Concept of Electrode Patterns 134 6-2-1 Experimental and Measurement Details 134 6-2-2 Parameters of Square and Comb-Shaped Electrodes 135 6-3 Edge-Dependent Inversion Tunneling Current Behavior 136 6-3-1 Edge-Dependent Current-Voltage Characteristics 136 6-3-2 Current Conduction Mechanism and Device Simulation 137 6-4 Characteristics of MOS Tunneling Photodiodes with Ultrathin SiO2 and HfO2 High-k Dielectrics 141 6-4-1 Thickness-Dependent Inversion Current of SiO2 MOS tunneling diodes 141 6-4-2 Comparison of Inversion Current Photoresponse for MOS Tunneling Photodiodes with Ultrathin SiO2 and HfO2 High-k Dielectrics 142 6-5 Summary 144 Chapter 7 Conclusion and Perspective 7-1 Conclusion 157 7-2 Perspective and Future Work 160 Appendix Antimony Doped Cadmium Telluride Semiconductor Nanowires: Synthesis, Characterization and Application A-1 Introduction 163 A-2 Experimental Details 165 A-3 Morphologies and Structure Characterization 167 A-4 Electrical Transport and Photoluminescence Characteristics 168 A-5 Photodetector Performance 173 A-6 Summary 175 References 191 Publication List 2136342080 bytesapplication/pdf論文公開時間：2019/07/22論文使用權限：同意有償授權(權利金給回饋本人)金氧半元件硝酸補償技術高介電係數氧化層可靠度不均勻度金氧半穿隧式溫度感測器金氧半穿隧式光二極體碲化鎘奈米線thesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/263833/1/ntu-103-F97943170-1.pdf