本研究利用陰極真空電弧沉積系統(Cathodic vacuum arc deposition system，CVAD)以低溫製程技術(< 75℃)製備純氧化鋅(Zinc oxide，ZnO)透明導電薄膜於高分子基板上。討論在不同製程變因下，薄膜的材料、光學、電學和機械特性。
實驗分析得知，純氧化鋅薄膜在不同高分子基板(PET、PVB、PI)中，所有特性差不多。藉由薄膜的透光導電性能係數(FOM)，PET、PVB與PI分別為1E-3、8E-4與8.2E-4。因此，後續研究選用PET作為本研究之基板。
研究氧化鋅/鋁金屬/氧化鋅三層結構的光電特性，鋁金屬作為導電性質的緩衝層。在鋁為定值(20 nm)狀態下，改變氧化鋅薄膜的厚度(50、100、150和200 nm)，探討各種光電性能，實驗結果得知氧化鋅(50 nm)/鋁金屬(20 nm)/氧化鋅(50 nm) 三層結構可作為一個良好的透明導電薄膜(50 nm：3.4E-4、100 nm：2.3E-5、150 nm：2.2E-5、200 nm：1.9E-5)。
在固定電弧電流在60A，氬氣氣體流量固定在20 sccm時，利用不同氧氣與氬氣氣體流量比(6：1、7：1、8：1、9：1和10：1)為變因，來製備氧化鋅薄膜，並進行薄膜性能比較。結果得知，氣體流量比在8：1時，薄膜的化學劑量比具有較佳值，其光學穿透性(86.38%)和電特性(電阻係數ρ：3.65 x10-3 Ω-cm，且載子移動率μ：4.83 cm2/V·s)皆比其他四項參數來的好。
在固定氧氣氬氣氣體流量比定於8：1之後，改變不同電流強度(40、50、60、70和80 A)看對純氧化鋅薄膜之影響。當電流強度在60A的時候，發現其有最佳的薄膜品質、光學穿透性(86.38%)和電特性(電阻係數ρ：5.88 x10-3 Ω-cm，且載子移動率μ：11.24 cm2/V·s)。
最後，本研究探討氧化鋅薄膜做於PET基板上機械性質，並與文獻樣品來做比較。在荷重力到在超過1980 uN及刮痕力道在超過40mN之後，顯示出對薄膜破壞情況。文獻指出，一厚度664nm之濺鍍氧化鋅摻鋁(ZnO：Al、簡寫為AZO)薄膜，在荷重800uN時，會產生薄膜破裂之情況。另一厚度約300nm於PET基板上之濺鍍氧化鋅薄膜，在刮痕力道約30mN時，就會產生薄膜與基板分離之情況。在相似的條件，針對氧化鋅薄膜之硬度與基板之間的附著性，陰極電弧製備的氧化鋅薄膜優於濺鍍系統製備的氧化鋅。

This work investigated pure, conductivity and transparency zinc oxide (ZnO) thin films on the polymer substrates at a low temperature (< 75℃) by using cathodic vacuum arc deposition (CVAD) system. We reported the material, optical, electrical and mechanical properties of ZnO thin film with various processing conditions.
The pure ZnO thin films were deposited on the various polymer substrates such as PET, PVB and PI substrate and the properties of the deposited ZnO tin films were investigated. The figure of merit (FOM) based on the transparent and conductive property was used to determine the quality of the deposited ZnO thin film on the various polymer substrate. The FOM for PET, PVB and PI were 1E-3, 8E-4 and 8.2E-4. Therefore, the PET substrate was selected in the following research.
The ZnO/Al/ZnO multistructure is a good transparent and conductive thin film with Al is a seed buffer layer. The Al thickness of 20 nm was a fixed and the thickness of the ZnO film were varied with 50, 100,150 and 250 nm. When the thickness of ZnO thin film was in the 50 nm, the ZnO/Al/ZnO multistructure has a value of FOM (50 nm：3.4E-4, 100 nm：2.3E-5, 150 nm：2.2E-5, 200 nm：1.9E-5).
ZnO thin films were deposited with the different O2/Ar gas flow ratio (6：1, 7：1, 8：1, 9：1 and 10：1, Ar gas flow in 20 sccm). The average transmittance of 86.38% in the visible region and the resistivity (ρ) of 3.65 x10-3 Ω-cm with the mobility (μ) of 4.83 cm2/V·s was obtained for the ZnO thin film under O2/Ar 8：1.
With arc current in 60 A and the O2/Ar gas flow ratio in the 8：1, the effect of various arc currents (40、50、60、70 and 80 A) on the properties of the pure ZnO film were investigated. Under the arc current of 60 A, the deposited thin film had a high average transmittance of 86.38% in the visible region and the resistivity (ρ) of 5.88 x10-3 Ω-cm with the mobility (μ) of 11.24 cm2/V·s.
Finally, the mechanical properties of the deposited ZnO thin film on the PET substrate were investigated. It was found that the deposited ZnO thin film could bear under the load in 1980 uN and was cracked under the scratch load in 40 mN. Compared with the reference sample, the crack of sputtered Al-doped ZnO (AZO) film was appeared in the load of 800 uN as the AZO thin film thickness was 664 nm. The scratch load of sputtered ZnO thin film on PET substrate with 300 nm thickness was 30 mN. Thus, the deposited ZnO thin film by using CVAD system had better hardness and adhesion than those using sputtering system.

致謝 I
摘要 II
Abstract IV
Contents VI
List of Figures IX
List of Tables XIII
1- 1 Research Background 1
1- 2 Research status of the transparent conductive film 3
1- 3 Motivation and target 5
1- 4 Research structure 5
Chapter 2 Theory 7
2- 1 Properties of ZnO 7
2- 2 Material structure of ZnO 7
2- 3 Band gap structure of ZnO 9
2- 4 The electrical property 10
2-4- 1 The conductivity 10
2-4- 2 The carrier concentration 11
2- 5 The optical property 12
2- 6 Correlation of optical and electrical properties 14
2- 7 Defect level of ZnO 15
2- 8 Special nature of ZnO to transparent conductive characteristic 18
2- 9 The deposition methods of ZnO 18
2-9- 1 Magnetron Sputtering 18
2-9- 2 Pulsed Laser Deposition (PLD) 19
2-9- 3 Evaporation 19
2-9- 4 Chemical Vapor Deposition (CVD) 19
2-9- 5 Spray Pyrolysis 20
2-9- 6 Sol-Gel 20
2-9- 7 Cathodic Vacuum Arc Deposition (CVAD) 20
2- 10 Polymer substrate 21
2-10- 1 Poly(Ethylene) Terephthalate (PET) 21
2-10- 2 Poly(Vinyl) Butyral (PVB) 22
2-10- 3 Polyimide (PI) 22
Chapter 3 Experimental methods and procedures 23
3- 1 Experiment design 23
3- 2 Cathodic vacuum arc deposition 24
3- 3 Analysis equipment for ZnO thin film properties 25
3-3- 1 X-ray diffraction (XRD) 25
3-3- 2 Ultraviolet–visible spectroscopy (UV-Vis spectroscopy) 28
3-3- 3 Photoluminescence (PL) 29
3-3- 4 Four Point 32
3-3- 5 Hall measurement 33
3-3-6 Nanoindentaiton 36
4- 1Effect of various polymer substrates of ZnO Thin Films 39
1. Parameters 39
2. XRD analysis 39
3. UV analysis 41
4. Electrical properties 43
4-2 Effect of different ZnO thin film thickness on ZnO/Al/ZnO layer. 45
1. Parameters 45
2. XRD analysis 45
3. UV analysis 46
4. Electrical analysis 47
4-3 Effect of various gas flow ratio for ZnO thin film on the PET substrate. 50
1. Parameter 50
2. XRD analysis 50
3. UV analysis 53
4. PL analysis 55
5. Electrical property 56
4-4 Effect of arc current or ZnO thin film on the PET substrate. 59
1. Parameter 59
2. XRD analysis 59
3. UV analysis 62
4. PL analysis 64
5. Electrical property 65
4-5 The mechanical property or ZnO thin film on the PET substrate. 67
1. Parameter 67
2. Material, optical and electrical analysis 67
3. Mechanical analysis 68
Chapter 5 Conclusions 73
Reference 76

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