金屬氧化物半導體由於可廣泛的應用，所以近年來成為熱門的研究領域。金屬氧化物半導體能在低溫下沈積且擁有高載子遷移率，所以金屬氧化物將於下一新時代光電元件的應用上扮演重要的角色。
氧化鋅(ZnO)是一種II-VI族結合的金屬氧化物半導體，擁有3.37 eV寬的直接能隙。氧化鋅薄膜可藉由多種方法製作同時擁有高均勻度的載子濃度。在本論文中，元件的主動層為錫摻雜氧化鋅薄膜，使用溶膠凝膠(sol-gel)以旋轉塗佈(spin-coating)的方式製作，其元件結構為底閘極底接觸(bottom-gate bottom-contact)式的。
實驗結果得知錫摻雜氧化鋅薄膜電晶體(ZTO TFTs)的電性容易受到環境氧氣氛的影響。另外，關於改變環境氣氛的可靠度對錫摻雜氧化鋅薄膜電晶體影響也有所探討。最後，以溶膠凝膠方式製作的錫摻雜氧化鋅薄膜電晶體除了應用在開關元件上，也嘗試作為一個氧氣偵測器。

In recent years, ionic amorphous oxide semiconductors have become one of the hottest research fields due to their wide application. Ionic amorphous oxide semiconductors have high mobility even deposited at low temperature, therefore ionic amorphous oxide semiconductors will play the important roles for the next optoelectronic devices generation.
Zinc oxide (ZnO) is a II-VI compound semiconductor with a wide direct bandgap of 3.37 eV. Therefore, ZnO have uniform carrier concentration in different deposited process. In this study, the active channel layers of zinc tin oxide (ZTO) thin film transistors were fabricated by the sol-gel spin-coating method. These zinc tin oxide TFTs were fabricated by bottom-gate bottom-contact-type TFTs.
The Experimental results have shown that the electrical properties of the zinc tin oxide TFTs are strongly dependent on ambient oxygen. However, in this study, the dynamic gate bias stability on the electrical properties of zinc tin oxide TFTs have been investigated. In particular, the possibility of sol-gel Zinc tin oxide thin film transistors as a gas sensor is also discussed at last.

Chapter 1 3
Introduction 3
1.1 Overview 3
1.2 Motivation 5
Chapter 2 6
Background of Zinc oxide 6
2.1 Zinc oxide 6
2.2 Surface conductivity and Photoconductivity 7
2.3 Physisorption and Chemisorption 9
2.4 Scattering mechanism 11
Chapter 3 14
Fabrication and Instruments 14
3.1 Device Fabrication 14
3.1.1 TFT Fabrication 14
3.1.2 Deposition of Active channel layer by spin-coating 14
3.1.3 Baking 15
3.1.4 Patterning 15
3.1.5 Annealing 15
3.1.6 Film Thickness 16
3.2 Instruments and measurement setup 17
Chapter 1 3
Introduction 3
1.1 Overview 3
1.2 Motivation 5
Chapter 2 6
Background of Zinc oxide 6
2.1 Zinc oxide 6
2.2 Surface conductivity and Photoconductivity 7
2.3 Physisorption and Chemisorption 9
2.4 Scattering mechanism 11
Chapter 3 14
Fabrication and Instruments 14
3.1 Device Fabrication 14
3.1.1 TFT Fabrication 14
3.1.2 Deposition of Active channel layer by spin-coating 14
3.1.3 Baking 15
3.1.4 Patterning 15
3.1.5 Annealing 15
3.1.6 Film Thickness 16
3.2 Instruments and measurement setup 17
3.2.1 Instruments 17
3.1.2 Set up instruments for I-V 18
Chapter 4 19
Results and Discussion 19
4.1 The hysteresis phenomenon of ZTO TFT 19
4.1.1 Experiment 19
4.1.2 The hysteresis phenomenon 20
4.2 The stability under dynamic stress 21
4.2.1 Experiment 21
4.2.2 The dynamic stress in vacuum 22
4.2.3 The dynamic stress under different oxygen pressure 23
Chapter 5 24
Conclusion 24
Reference 25
Tables 30
Figures 32

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