在本篇研究論文中，我們在玻璃基板上生長氧化鋅奈米針以及奈米柱，並對其做了相關的物性光性化性等特性分析。從各特性分析，我們可以看出生長的氧化鋅奈米針及奈米柱皆有相似的趨勢，尤其在光致螢光(PL)的分析可以看出，峰值的位置(約位於409nm)較文獻常見的位置(375nm)紅移了約35nm，推測為奈米針及奈米柱的缺陷過多而造成。接著我們將生長後的奈米針及奈米柱於上方蒸鍍上銦鋅合金指叉式電極製成氣體感測器並對其做電流對時間的量測以觀測其光響應，發現其光響應隨著在笑氣下回火而有提高。為了減少電子電洞對復合機率，我們在氧化鋅奈米針及奈米柱底層長上一層二氧化鈦薄膜，形成ZnO nanotip/TiO2 film和ZnO nanorod/TiO2 film的異質接面結構，而後將其製成氣體感測器並做光響應的量測，發現奈米針及奈米柱兩者在光響應部分皆有明顯提升。最後我們可以得到氧化鋅奈米針長在二氧化鈦薄膜上的氣體感測器之光響應有22.85，上升時間40秒，下降時間82秒；氧化鋅奈米柱長在二氧化鈦薄膜上的氣體感測器之光響應有27.44，上升時間22秒，下降時間133秒。

In this study, zinc oxide (ZnO) nanotip and nanorod were grown on glass substrate by aqueous solution deposition (ASD). Both characteristics of the two nanostructures were investigated. For fabrication of ZnO nanostructure UV photodetector, In-Zn inter-digitated metal electrode was evaporated on the top of the grown ZnO nanostructure to form the contact via. Compared with the common value (375 nm), both the peaks from the PL spectra of ZnO nanotip and nanorod are red-shifted (409 nm) due to the massive defects in nanotip and nanorod. In order to improve the photosensiblity, heterojunction of ZnO nanostructure/TiO2 film was prepared and were made into UV photodetector. Photoresponses of both nanotip and nanorod were improved after N2O annealing at 300oC. With the heterojunction of ZnO 1D nanostructure on TiO2 film, the photoresponses of both ZnO nanotip/TiO2 film can reach to 22.85, and the rise time and decay time are 40 and 82 seconds, respectively. On the other side, the photoresponses of both ZnO nanorod/TiO2 film can reach to 27.44, and the rise time and decay time are 22 and 133 seconds, respectively.

ACKNOWLEDGEMENT ii
中文摘要 iii
ABSTRACT iv
CONTENTS v
LIST OF FIGURES vii
LIST OF TABLES ix
Chapter 1 …………………………………………………………………………...1
Introduction 1
1.1 Properties of ZnO one-dimensional nanostructures 1
1.2 ZnO-based gas sensor 2
1.3 Growth methods for ZnO one-dimensional nanostructures 5
1.4 Advantages of aqueous solution deposition (ASD) 6
1.5 Motivation 6
References 12
Chapter 2 15
Experiments 15
2.1 Substrate cleaning 15
2.2 RF sputtering for ZnO nucleation 15
2.3 ASD of ZnO nanotip and nanorod 16
2.3.1 Deposition process 16
2.3.2 Basic mechanism 17
2.4 Structure of ZnO 1D nanostructure gas sensor 19
2.5 ZnO 1D nanostructure/TiO2 film gas sensor 20
2.5.1 ASD-TiO2 film 20
2.5.2 Structure of ZnO 1D nanostructure/TiO2 film gas sensor 21
2.6 Characterization 21
2.6.1 Physical properties 21
2.6.2 Chemical properties 23
2.6.3 Optical properties 23
2.6.4 Electrical properties of gas sensor 25
References 33
Chapter 3 34
Results and Discussion 34
3.1 Physical properties of ZnO nanotip and nanorod 34
3.1.1 ZnO nanotip 34
3.1.1 ZnO nanotip 34
3.1.2 ZnO nanorod 34
Chemical properties of ZnO nanotip and nanorod 35
3.3 Optical properties of ZnO nanotip and nanorod 35
3.4 Electrical properties of gas sensor 36
3.4.1 Photoreponse of ZnO nanotip and nanorod gas sensor 36
3.4.2 Photoreponse of ZnO nanotip and nanorod on TiO2 film heterojunction gas sensor 37
References 59
Chapter 4 60
Conclusions 60

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