近年來，一些透明且導電的金屬氧化物，例如氧化鎘、氧化銦、氧化錫和氧化鋅，已可以用於半導體上的透明薄膜，因此透明電子將是下一新時代光電元件上應用的重要技術。
氧化鋅(ZnO)是一個II-VI族結合的半導體材料，擁有3.37 eV寬的直接能隙，因此，氧化鋅應用在透明薄膜電晶體(TFTs)已經被廣泛地研究，而對於氧化鋅薄膜在多樣化的應用來說，許多的製作方法也已經被嘗試在做。在本論文中，元件的主動層為鋯摻雜氧化鋅薄膜，是使用一種溶膠凝膠(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。
實驗結果得知鋯摻雜氧化鋅薄膜電晶體(ZrZnO TFTs)的電性強烈受到可見光和周遭的氧影響。另外，關於溫度對鋯摻雜氧化鋅薄膜電晶體的電性上影響結果也在此探討。最後，以溶膠凝膠方式製作的鋯摻雜氧化鋅薄膜電晶體除了應用在開關元件上，在氣體感應器上的應用也具有極大潛力。

In recent years, transparent and conductive layers of some metallic oxide, such as cadmium oxide, indium oxide, tin oxide and zinc oxide, can be used for semiconducting transparent coatings. Transparent electronics are nowadays a crucial technology for the next generation of optoelectronic devices.
Zinc oxide (ZnO) is a II-VI compound semiconductor with a wide direct bandgap of 3.37 eV. Therefore, ZnO based transparent thin film transistors (TFTs) have been studied extensively. For the wide variety of applications, numerous ZnO films preparation methods have been attempted. In this thesis, the devices of ZnZrO active channel layers were fabricated by the sol-gel spin-coating method. These ZnZrO TFTs were fabricated by bottom-gate bottom-contact-type TFTs.
The Experimental results have shown that the electrical properties of the ZnZrO TFTs are strongly dependent on visible light and ambient oxygen. In addition, in this study, the results concerning the influence of temperature on the electrical properties of ZnZrO TFTs also have been discussed. Finally, except for the application of switch devices, the ZnZrO TFTs by sol-gel spin-coating process exhibits a potential application for gas sensors.

Content
Chinese Abstract……………………………………………………..i
English Abstract……………………………………………………..ii
Acknowledgement…………………………………………………..iii
Content……………………………………………………………....iv
Table Captions……………………………………………………..vii
Figure Captions……………………………………………………viii
Chapter 1 – Introduction
1.1 Overview…………………………………………………………. 1
1.2 Motivation………………………………………………………... 3
Chapter 2 – Background of Zinc oxide
2.1 Zinc oxide.......................................................................................4
2.2 Surface conductivity and Photoconductivity..................................5
2.3 Physisorption and Chemisorption……………………………….7
2.4 Scattering mechanism…………………………………………….8
Chapter 3 – Fabrication and instruments
3.1 Device Fabrication........................................................................11
3.1.1 TFT Fabrication………………………………………………….11
3.1.2 Deposition of Active channel layer by spin-coating…………11
3.1.3 Baking……………………………………………………………..12
3.1.4 Patterning…………………………………………………………12
3.1.5 Annealing………………………………………………………….12
3.1.6 Film Thickness……………………………………………………13
3.2 Instruments and measurement step……………………………...14
3.2.1 Instruments………………………………………………………..14
3.2.2 Set up instruments for I-V……………………………………….15
Chapter 4 – Results and Discussion
4.1 The influence of illumination…………………………………...16
4.1.1 Experiment………………………………………………………..16
4.1.2 The influence of illumination under atmosphere…………….17
4.1.3 The influence of illumination under vacuum…………………18
4.1.4 The different wavelength of illumination……………………..19
4.2 The influence of ambient gas…………………………………....20
4.2.1 Experiment………………………………………………………..20
4.2.2 The influence of ambient gas under various pressures……...21
4.3 The steady state of the device…………………………………...22
4.3.1 Experiment………………………………………………………..22
4.3.2 The steady state of time mode and bias mode………………..23
4.3.3 The steady state of bias mode after illumination…………….23
4.4 The influence of temperature…………………………………....25
4.4.1 Experiment………………………………………………………..25
4.4.2 The influence of temperature under atmosphere…………….25
4.4.3 The influence of termperature under vacuum………………..26
Chapter 5 – Conclusion....................................................................27
References…………………………………………………………..29
Tables…………………………………………………….………....35
Figures……………………………………………………………....37

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