臺灣博碩士論文加值系統

本論文之研究重點將針對 ZnGa2O4 進行全面的研究，ZnGa2O4 為一種寬能隙半導體材料，對光電和功率電子應用具有可觀的潛力，該材料具有高熱穩定性、優異的光電性能和紫外吸收能力等獨特特性，使其成為製作先進元件的理想材料。本研究使用射頻磁控濺射技術，在最密堆積面之藍寶石基板上沉積了 ZnGa2O4 和鋁摻雜 ZnGa2O4 薄膜，並利用X光繞射儀、掃描式電子顯微鏡、穿透式電子顯微鏡、原子力顯微鏡和光致螢光光譜等表徵技術對其薄膜的結晶結構、組成形態和光學性質進行了系統地分析。同時，研究了基於鋁摻雜 ZnGa2O4 薄膜的深紫外光探測器特性及光致螢光特性之表徵分析。此外，透過 ZnGa2O4 薄膜與 NO 氣氛進行反映實驗，從響應時間和恢復時間的結果顯示，這些薄膜對特定氣體具有高靈敏度與專一選擇性，並與現有的氣體感測材料進行了比較，未來將很有機會應用於氣體感測領域中。研究結果表明，通過射頻磁控濺射技術製備的 ZnGa2O4 和鋁摻雜 ZnGa2O4 薄膜具有優異的深紫外光探測特性、光致螢光特性和潛在的氣體感測能力。這些研究成果有助於深入了解 ZnGa2O4 薄膜的生長過程和特性，並為開發先進的光電元件和氣體感測技術提供重要的基礎，從其之特性表現可以知道，ZnGa2O4 薄膜未來將非常有機會成為多功能元件應用的先進材料。

This dissertation focuses on the comprehensive study of ZnGa2O4, a wide-bandgap semiconductor with exceptional properties that hold significant promise for both optoelectronic and power electronic applications. The unique characteristics of ZnGa2O4, including its high thermal stability, excellent electrical properties, and UV absorption capabilities, make it an attractive material for advanced device fabrication. ZnGa2O4 films and Al-doped ZnGa2O4 films were deposited on c-plane sapphire substrates using RF magnetron sputtering. The structural, morphological, and optical properties of the films were analyzed using X-ray diffraction, scanning electron microscopy, atomic force microscopy transmission electron microscopy, and photoluminescence spectroscopy etc. Photoluminescence characterization of the Al-doped ZnGa2O4 films was performed to investigate their phosphor properties. The deep-ultraviolet photodetector characteristics based on Al-doped ZnGa2O4 film are also investigated. Furthermore, the gas sensing characteristics of the ZnO: ZnGa2O4 films were evaluated by conducting experiments with NO target. The films demonstrated high sensitivity and selectivity towards specific gases, making them ideal candidate for gas sensing applications. The response and recovery times of the gas sensor were determined, and their performance was compared to existing gas sensing materials. The results indicate that RF magnetron sputtered Al-doped ZnGa2O4 films possess excellent photoluminescence and deep-ultraviolet photodetector characteristics whereas ZnO: ZnGa2O4 films possess promising gas sensing capabilities. These results contribute to the understanding of the growth process and characterization of ZnGa2O4 based films, providing valuable insights for the development of advanced optoelectronic devices and gas sensing technologies. The combination of deep-ultraviolet photodetector, photoluminescence, and gas sensing characteristics makes ZnGa2O4 based films a versatile material for a wide range of next generation applications.

摘要 i
Abstract ii
Table of Contents iii
List of Tables v
List of Figures vi
Chapter 1. Introduction 1
1.1 Basic Properties 1
1.2 Crystal Structure 1
1.3 Defect Structure 2
1.4 Conductivity Control and Doping 2
1.5 Research Gap and Motivation 3
Chapter 2. Growth Method, Characterization Techniques, and Experimental 6
2.1 Growth Method: Radio-Frequency Magnetron Sputtering 6
2.2 Characterization Techniques 8
2.2.1 Structural Characterization 8
2.2.2 Surface Morphology 10
2.2.3 Optical Characterization 13
2.2.4 Electrical Characterizations 16
2.3 Experimental 16
2.3.1 Growth of Aluminum-doped ZnGa2O4 films for phosphor and DUV PDs16
2.3.2 Growth of ZnO: ZnGa2O4 films for NO gas sensor 17
Chapter 3. Results and Discussion 19
3.1 Growth of Aluminum-doped ZnGa2O4 films for Phosphor and Deep-Ultraviolet Photodetector Applications 19
3.1.1 Film Characteristics 19
3.1.2 Devices (Phosphor and DUV PDs) 25
3.2 Growth of ZnO: ZnGa2O4 films for Gas Sensor Applications 28
3.2.1 Film Characteristics 28
3.2.2 Gas Sensor 32
Chapter 4. Conclusions 36
Chapter 5. Future Work and Publications 37
5.1 Future Work 37
5.2 Publications 37
References 39

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