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博碩士論文 etd-0728112-134938 詳細資訊
Title page for etd-0728112-134938
論文名稱 Title |
運用微機電系統技術開發可應用於微波通訊系統之微型變壓器 Development of Micro-transformer by MEMS Technology for Microwave Communication System |
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系所名稱 Department |
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畢業學年期 Year, semester |
語文別 Language |
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學位類別 Degree |
頁數 Number of pages |
104 |
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研究生 Author |
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指導教授 Advisor |
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召集委員 Convenor |
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口試委員 Advisory Committee |
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口試日期 Date of Exam |
2012-07-14 |
繳交日期 Date of Submission |
2012-07-28 |
關鍵字 Keywords |
微機電系統、微波通訊系統、微型變壓器、品質因子、插入損失、懸浮式結構 suspending structure, insertion loss, quality- factor, micro transformer, microwave communication system, MEMS |
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統計 Statistics |
本論文已被瀏覽 5689 次，被下載 0 次 The thesis/dissertation has been browsed 5689 times, has been downloaded 0 times. |
中文摘要 |
傳統平面式微型變壓器因為採用平面式結構，故在高頻操作時大部分電磁波能量會經矽基板而散逸，進而導致元件品質因子低於10以下以及插入損失高達-6 ~ -10 dB。為了提升品質因子與降低插入損失，本論文運用微機電系統技術開發一種具懸浮式結構之雙埠與三埠微型變壓器，其主要結構是由兩個互相纏繞且具懸浮結構之微型電感器組成，而每個微型電感器是由厚度為0.32 µm 之氮化鉭/鉭/銅底電極、高度為10 µm 之銅支撐柱及厚度為6 µm 之螺旋銅導體層所構成。 本研究採用田口法與商用電磁模擬軟體(Ansoft-HFSS)分析矽基懸浮式微型變壓器之最佳化銅導體層尺寸，並且模擬該元件之高頻特性，包括電感值、磁耦合系數、品質因子、不平衡振幅差、不平衡相位差、共模拒斥比與插入損失。本論文在製程方面主要是採用面型微加工與電化學沉積技術以完成懸浮式微型變壓器之製作，製作流程包含五次光學微影製程與八次薄膜沉積製程。 經商用網路分析儀(Agilent-E8364B)與模擬軟體(Agilent-ADS)之量測與分析，本論文所開發之雙埠變壓器於5.2 GHz中心頻率下，具有高磁耦合系數(0.78)與相當高之品質因子(17.20)。在相同操作頻率下，所製備之三埠變壓器亦具有相當低之不平衡振幅差(-0.02 dB)與不平衡相位差(1.65°)，以及相當高之共模拒斥比(36.78 dB)與極低之插入損失(-4.52 dB)。本論文所開發之微型變壓器，其晶片尺寸僅為0.7 mm×0.7 mm×0.5 mm且具有優良之高頻特性，所以相當適合應用於可攜式微波通訊系統之中。 |
Abstract |
The conventional planar micro transformers presented very low quality-factor (Q<10) and very high insertion loss (-6 ~ -10 dB) at high operation frequency since most of the microwave power is dissipated through the silicon substrate. To increase the quality-factor and reduce the insertion loss of silicon-based transformers, this dissertation presents a two-port and three-port micro transformers with suspending structure utilizing the micro-electro-mechanical systems (MEMS) technology. The proposed silicon-based transformers are constructed by two winding and suspending micro inductors. Each suspending micro inductor consists of a 0.32 µm-thick TaN/Ta/Cu bottom electrode, a 10 µm-height supporting copper vias and a 6 µm-thick spiral copper conducting layer. This research adopts the Taguchi method and commercial electromagnetic simulation software (Ansoft-HFSS) to optimize the dimensional specifications of the copper conducting layer. Many high frequency characteristics of the suspending micro transformers are simulated, including the inductance, the magnetic coupling factor, the quality-factor, the magnitude imbalance, the phase imbalance, the common mode rejection ratio (CMRR) and the insertion loss. In this research, the surface micromachining and electrochemical deposition techniques are used to implement the suspending micro transformers. The main fabrication steps include five photolithography and eight thin-film deposition processes. According to the simulation and measurement results from the commercial network analyzer (Agilent-E8364B) and software (Agilent-ADS), the implemented two-port transformer demonstrates a high magnetic coupling factor (0.78) and a very high quality-factor (Q=17.20) at 5.2 GHz. On the other hand, the proposed three-port transformer presents a low magnitude imbalance (-0.02 dB), a low phase imbalance (1.65°), a high CMRR (36.78 dB) and a very low insertion loss (-4.52 dB) under the same operation frequency. In this dissertation, a novel suspending micro transformer has been developed and characterized. The proposed micro transformer is very suitable for being used in the portable microwave communication system due to its small chip size (0.7 mm×0.7 mm×0.5 mm) and excellent high-frequency characterization. |
目次 Table of Contents |
Acknowledgement i Abstract(in Chinese) iii Abstract(in English) iv Contents vi List of Figures viii List of Tables xii Chapter 1 Introduction 1 1-1 Research Motivation 1 1-2 Review of Transformer 3 1-3 Overview of Dissertation 11 Chapter 2 MEMS Technology and Basic Transformer Theory 13 2-1 MEMS Technology 13 2-1-1 Surface Micromachining 15 2-2 Basic Micro Transformer Theory 18 2-2-1 Two-port Micro Transformer 18 2-2-2 Three-port Micro Transformer 23 2-2-3 Suspending Structure 26 Chapter 3 Design and Simulation of Micro Transformer 28 3-1 Introduction 28 3-2 Process Flow Design 33 3-3 Simulation Results and Discussion 36 3-3-1 Two-port Micro Transformer 36 3-3-2 Three-port Micro Transformer 41 Chapter 4 Fabrication of Micro Transformer .45 4-1 Layout Design 45 4-1-1 Two-port Micro Transformer 45 4-1-2 Three-port Micro Transformer 48 4-2 Fabrication Process Flow 50 4-2-1 Two-port Micro Transformer 50 4-2-2 Three-port Micro Transformer 54 Chapter 5 Characterization Results and Discussion 59 5-1 Key Problems and Solve Methods 59 5-1-1 GSG Bottom Electrodes of Micro Transformer 59 5-1-2 Supporting Copper Vias of Micro Transformer 61 5-1-3 Spiral Copper Conducting Layer of Micro Transformer 62 5-1-4 Microstructures Inspection by SEM 64 5-2 Simulation and Measurement Results 66 5-2-1 Two-port Micro Transformer 66 5-2-2 Three-port Micro Transformer 71 Chapter 6 Conclusion and Future Works 74 6-1 Conclusion 74 6-2 Future Work 75 Bibliography 77 |
參考文獻 References |
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